Calculation of chewing efficiency. Chewing efficiency. Examination of teeth and dentition
Question 506.
Patient M., 60 years old. Dental formula: v / h 00000320/00000000; on n / h 00004321/12300 Determine the chewing efficiency according to Agapov:
Question 507.
The patient has a breakage of a partial removable plate prosthesis of the upper jaw. After examining the prosthesis, the doctor decided that the prosthesis should be repaired. Determine why the doctor made this decision:
(+) The fracture line is in the area of \u200b\u200bthe preserved teeth
() The patient tried to glue parts of the prosthesis on his own
() The fracture line has a complex relief
() The prosthesis is broken several times
() Multiple fine splinter fractures
Question 508.
Select the components of the bridge:
(+) Support crowns, body
() Clammer, basis
() Basis, body
() Support-retaining clasps
() Artificial teeth, basis
Question 509.
Select mechanical devices designed for retention and stabilization of dentures and consisting of two parts - matrix and male:
(+) Attachments
() Telescopic crown
() One-shoulder bent clasp
() Implant-clasp systems
() Beam fastening systems
Question 510.
Patient E., 25 years old, complained of a sudden blockage of movements in the temporomandibular joint. At the same time, pain in the joint area is noted. Anamnesis: These symptoms appeared after opening the mouth wide while biting off an apple. The patient notes that when pressing with a finger in the area of \u200b\u200bthe joint, the movements of the lower jaw are restored. Objectively: the face is symmetrical, the skin is clean, the bite is orthognathic, pale pink. There are fillings on 16, 17 teeth. Choose the most probable diagnosis:
(+) Dislocation of the meniscus
() Dislocated jaw
() Fracture of the lower jaw
() Neurogenic contracture
() Microstomy
Question 511.
Patient J., 52 years old, complained of a sensation of metal taste and a feeling of acid in the mouth. Anamnesis: had prosthetics 2 months ago. Objectively: the mucous membrane of the oral cavity was unchanged, in the oral cavity there are prostheses made of dissimilar materials (bridges made of gold alloy, stainless steel), fixed bite. Skin tests for nickel, chromium, cobalt are negative. Choose the most likely diagnosis:
(+) Galvonosis
() Traumatic stomatitis
() Allergic stomatitis
() Chemical-toxic stomatitis
() Toxic stomatitis
Question 512.
In patient N., an objective examination revealed increased abrasion of hard tooth tissues, a decrease in the vertical dimensions of the crowns of all teeth, a decrease in the interalveolar height, the height of the lower third of the face was not changed. Choose the most likely diagnosis:
(+) Generalized compensated increased abrasion of hard tissues of teeth
() Localized compensated wear
() Localized uncompensated increased tooth wear
() Generalized subcompensated form increased tooth wear
() Generalized uncompensated form increased tooth wear
Question 513.
Patient G. 62 years old. Objectively: the upper and lower jaws have well-defined alveolar processes covered with a slightly pliable mucous membrane. The palate is also covered with a uniform layer of mucous membrane, moderately malleable in the posterior third. Natural folds of the mucous membrane (frenulum of the lips, cheeks and tongue / both on the upper and lower jaw are sufficiently far from the apex of the alveolar part. Choose the most probable diagnosis:
(+) I class according to Supple
() II class according to Supple
() IІI class according to Supple
() IV class according to Supple
() V class according to Supple
Question 514.
A 35-year-old patient complains of the absence of an 11 tooth, a cosmetic defect, a violation of phonetics. The tooth was removed 2 weeks ago due to complicated caries. Objectively: 11 tooth is missing. Mucous membrane without pathology. Orthognathic bite. 21.12 resistant, percussion is painless. Choose the most likely diagnosis:
(+) IV class according to Kennedy
() I class according to Kennedy
() I class according to Gavrilov
() IV class according to Gavrilov
() ІІІ class according to Kennedy
Question 515.
A 63-year-old patient complained of unilateral pain. Crunching and stiffness of the lower jaw, especially in the morning. Noise in the joints, headaches. Objectively: the absence of lateral 28, 27, 26, 46, 47, 48 teeth in 14, 13, 12, 11, 21, 21, 22, 23, 24, 25 teeth revealed pathological abrasion of the teeth. When the lower jaw is opened, the jaw moves to one side. Opening of the mouth is limited to 3 cm. On palpation of the lateral pterygoid muscle it is painless. Choose the most likely diagnosis:
(+) Arthrosis of the TMJ
() Facial nerve cut
() Neuromuscular dysfunctional syndrome
() Articulation occlusive syndrome
() Dislocation of the temporomandibular joint
Question 516.
Patient I., 30 years old, applied to the orthopedic office with complaints about the destruction of the crown and discoloration of the 12th tooth. IROPZ -0.8. The most effective treatments are:
(+) Restoration of the stump pin metal inlay, prosthetics with a ceramic crown
() Pinning with an anchor pin, restoration with light-curing plastic
() prosthetics with a metal-ceramic crown
() Pin tooth according to Richmond
() Simple pin tooth
Question 517.
Patient V., 48 years old, came to the clinic with complaints of tooth mobility with impaired chewing function. Objectively: the upper lip protrudes slightly, the crowns of the upper central teeth are fan-shaped. Teeth 11, 12, 13, 14, 21, 22, 23, 24 are mobile I degree, teeth 28, 27, 26, 36, 37, 38 are missing. Orthognathic bite. There are three and diastemas between the teeth. The necks of the teeth are bare. On palpation on all teeth, periodontal pockets secrete a small amount of pus. The gums are hyperemic, edematous. Select, The most likely treatment is:
(+) Circular stabilization using a clasp prosthesis
() Sagittal stabilization using equatorial crowns
() Parasagittal stabilization using a half-crown splint
() Frontal stabilization using a cap splint
() Frontal stabilization with a bridge
Question 518.
The patient complained about the destruction of the crown of 17 tooth. Anamnesis: 17 tooth was treated for caries and was repeatedly treated by a dentist. The inserted seal fell out 2 times. Objectively: the clinical crown of tooth 17 is low, there is an extensive filling on the occlusal surface of the tooth. The tooth is pulped, the percussion is negative, on the roentgenogram the root canals are filled to the apex of the roots. There are no pathological changes. The most likely treatment is:
(+) Pin tooth according to Richmond
() Plastic crown
() Core crown
() Solid crown
() Plastic crown with pin
Question 519.
Clinical stages of manufacturing a metal-ceramic crown: 1determination of the central occlusion; 2adding the crown; 3 fixation of the crown 4 insertion of the framework 5 preparation of the tooth and taking impressions. Answers:
Question 520.
A 56-year-old patient complains of insufficient fixation of the prosthesis on the lower edentulous jaw during the function of chewing and talking. Objectively: the presence of a wide, voluminous language filling the free space is determined. The most effective treatment is:
(+) Create a recess in the base from the lingual side
() Extend denture margins
() Make an elastic pad under the denture base
() Relining with self-hardening plastic
() Redesign a removable denture
Question 521.
A 44-year-old patient turned to the clinic of orthopedic dentistry with a complaint about the destruction of the 26th tooth. Objectively: the clinical crown of the 26 tooth is low, destroyed by caries, IROPZ-0.8, the tooth is depulpated. The percussion is negative. On the roentgenogram, the root canals are filled up to the apex of the roots. The most effective treatment is:
(+) Root pinning followed by prosthetics with a stamped crown
() Restorative filling made of light-curing plastic
() Restoration of the filling with subsequent prosthetics with a stamped crown
() Plastic restoration crown
() Restorative filling with subsequent prosthetics with a metal-ceramic crown
Question 522.
The place of correction of the individual spoon on the lower jaw according to the Herbst technique when the tongue moves to the side of the cheek with the mouth half open:
(+) Hyoid margin at 1 cm from the midline
() Zone of the jaw-hyoid line
() Areas of the mandibular tubercles
() Vestibular surface from canine to canine
() In the area of \u200b\u200bthe frenum of the tongue
Question 523.
Bolnoy 35 years old. complained of the absence of teeth in the upper jaw. Anamnesis: teeth were removed within 10 years due to complicated caries. Not previously had prosthetics. Objective data: the absence of 2.4,2.5,2.6,2.7 teeth. Displacement and enlargement of the alveolar process in the area of \u200b\u200bteeth 3.3,3.5,3.6,3.7, but no exposure of the tooth root and the formation of a gingival pocket are noted. The relationship between the extra- and intra-alveolar portion of the teeth remains unchanged. The most likely diagnosis is:
(+) Popov-Godon phenomenon, first form
() Partial adentia, complicated by pathological abrasion of hard tissues of the teeth and a decrease in the occlusal height;
() Partial edentulousness of both jaws, when not a single pair of antagonistic teeth is preserved.
() Partial adentia, complicated by a decrease in the occlusal height and distal displacement of the lower jaw;
() Popov-Godon phenomenon, second form, first subgroup
Question 524.
Determination of central occlusion using wax bases with occlusal rollers in the presence of antagonizing pairs of teeth; 1 sequential adjustment of the upper and lower rollers before closing the antagonist teeth 2 Assessment of the production quality of wax bases with occlusal rollers 3 gluing a heated wax plate onto wax rollers and fixation of the central wax rollers and fixation 4 lower wax rolls before closing the antagonist teeth 5 drawing landmarks for setting artificial teeth drawing up models in the central occlusion and checking the correctness of its definition Answers:
Question 525.
Bilateral terminal defect of the lower jaw to which class belong according to Kennedy:
(+) I class
() ІІІ class
() IV class
() ІІ class
Question 526.
What type of fixation are attachments:
(+) to mechanical
() to physical
() to chemical
() to biological
() to combined
Question 527.
The coronal part of the 2.3 tooth is destroyed, the Index of destruction of the occlusal surfaces of the teeth (IROPZ)\u003e 0.7. The bite is deep. What design of the pin tooth do you offer:
(+) one-piece pin tooth
() simple pin tooth
() pin tooth according to Richmond
() stump crown
() stump pin tab
Question 528.
A 25-year-old patient has applied to the orthopedic dentistry clinic with complaints of constant loss of the filling. On examination, the 2.6 crown is destroyed by 1/3 of the height of the crown of the tooth, the tooth is sealed, the antagonizing teeth are not in contact. To make a restoration metal stamped crown for a 2.6 tooth, the doctor prepared a 2.6 tooth, took a partial anatomical impression from the upper jaw. When fitting the crown, it was found that the crown overestimates the occlusion. At what stage was the mistake made, why the occlusion is overestimated:
(+) 1-clinical stage, the impression was taken incorrectly;
() 1-laboratory stage, the crown is not stamped correctly;
() 1-laboratory stage, the tooth is not correctly modeled;
() 1-clinical stage, incorrectly prepared tooth;
() 1- laboratory stage, the model was received incorrectly;
Question 529.
At the 2nd clinical stage of the manufacture of a metal-ceramic crown, the metal frame is effortlessly fitted to the tooth stump, exactly adjoins the ledge, the interocclusal gap with antagonist teeth is 0.5 mm, the thickness of the metal cap is 0.8 mm. Determine what complications may be:
(+) chipped ceramic mass
() poor crown retention
() de-cementing the crown
() aesthetic crown defect
() perforating the metal cap
Question 530.
The patient is missing 2.2; 2.3; 2.4; 2.5; 2.6 teeth, 1.1; 2.1; 2.7 the teeth are intact, no pathological changes have been identified, the doctor recommends the patient to make metal-ceramic bridges with supports on 1.1; 2.1 and 2.7 teeth. Determine if the correct abutment and denture design are selected:
() Wrong - abutment teeth are not pulped
() Correct - bridges completely restore chewing pressure
() Correct - aesthetically pleasing, quickly gets used to the prosthesis
() Wrong - the number of abutment teeth is insufficient
Question 531.
A 50-year-old patient has asked to make a bridge in the absence of 2.1; 1.1; 2.2 teeth. At the stage of fitting a combined metal bridge with plastic facets, the doctor fitted the prosthesis to the abutment teeth and found that in the position of the central occlusion only the upper incisors with facets close, and the rest of the teeth do not close. The solder at the soldering point between the crown of tooth 13 and the intermediate part touches the gingival papilla. Determine the further actions of the doctor:
(+) free the gingival papilla from solder and remove the contact area of \u200b\u200bthe facet
() free the papilla from the intermediate part of the bridge
() free the gingival papilla from solder and insert the bridge deeper
() free the gingival papilla from the facet and solder, prepare the abutment teeth
() free the gingival papilla from the solder, prepare the antagonist teeth;
Question 532.
Is the use of stamped metal crowns effective in case of pathological abrasion of the II degree of posterior teeth, initiate why:
(+) not effective, because complications associated with trauma to the marginal periodontium by the edge of the crown crown are possible
() effective, because it restores the bite to the thickness of metal stamped
() not effective, because it does not restore the anatomical shape of erased teeth in the posterior region
() effective, because a thick layer of cement between the occlusal surface of the erased tooth and the occlusal surface of the crown prevents the edge of the crown from moving under the gum
() not effective, because the thickness of the metal stamped crowns is not sufficient to restore the bite
Question 533.
The patient has a toothless upper jaw. Atrophy of the alveolar process of moderate degree, mild tubercles, average depth of the palate, pronounced torus. Your diagnosis:
(+) complete secondary adentia, type II according to Oxman
() complete secondary adentia, I - type according to Oxman
() complete secondary adentia, ІІ - type according to Supple
() complete secondary adentia, type III according to Oxman
() complete secondary adentia, ІІІ - type according to Supple
Question 534.
For a patient, when fitting an individual spoon on the lower jaw using functional tests according to Herbst, at the moment of swallowing the impression spoon is displaced from the lower jaw, determine the doctor's tactics:
(+) the spoon must be shortened in the area from the place behind the tubercle to the maxillary-hyoid line
() the spoon in such cases is shortened along the vestibular edge behind
() the spoon is shortened along the vestibular edge in front
() the spoon is shortened along the jaw-hyoid line
() the spoon is shortened in the area between the canines on the vestibular side
Question 535.
At the 3rd clinical stage after the introduction of the wax constructions of the prosthesis, in the position of the central occlusion there is a gap between the frontal teeth, when the n / h is displaced forward, the teeth close tightly along the entire dental arch. Determine at what stage the error occurred, because of what:
(+) at the 2nd clinical stage, when determining the CO, anterior occlusion was fixed;
() at 2-laboratory stage, when setting artificial teeth;
() at the 2nd laboratory stage, the models are incorrectly fixed in the occluder;
() at the 2nd clinical stage, when determining the CO, lateral occlusion was recorded;
() at the 2nd clinical stage, the wax construction of the prosthesis is deformed;
Question 536.
The patient has a bilateral terminal defect of the dentition in the lower jaw. Dental formula: 00004321/12340000 A partial removable plate prosthesis with retaining clasps for 34 and 44 teeth was made. Determine what type of clasp fixation of a removable denture is indicated:
(+) transversal
()transverse
() point
() sagittal
()diagonal
Question 537.
The patient has a diagnosis: "Defect of the dentition in the lower jaw, grade 3 according to Kennedy." Treatment plan: a composite bridge with supports for 37 and 33 teeth Assess why such a design was chosen:
(+) due to large convergence of teeth limiting the defect
() due to the included lateral dentition defect
() due to the mobility of the abutment teeth, limiting the defect
() due to the large extent of the dentition defect
() due to deep bite, when teeth are closed
Question 538.
Dental formula: 87650321/12345000 Diagnose and determine the chewing efficiency according to Agapov:
(+) ІІ class ІІІ subclass according to Kennedy, 30%
() ІІІ class IV subclass according to Kennedy, 20%
() І class ІІІ subclass according to Kennedy, 40%
() ІІІ class 1 Kennedy subclass, 50%
() ІІІ class IV subclass according to Kennedy, 60%
Question 539.
The stump of the tooth is cylindrical, where the diameter of the clinical neck of the tooth is equal to the diameter of the tooth at the level of the clinical equator, but with additional preparation of the vestibular surface, it retains a conical shape with a ledge at the level of the gums, separation of the teeth of the antagonists in the bite is 1.5-2.0 mm. Determine which artificial crown this tooth is prepared for:
(+) combined
() porcelain
() stamped metal
() plastic
() equatorial crown
Question 540.
The patient received a stamped-brazed bridge prosthesis. The gums in the area of \u200b\u200bthe prosthesis are hyperemic, edematous. When probing, the edges of the crown are not detected. Determine at what stage the mistake was made:
(+) on 3-clinical
() on the 1st laboratory
() at 2.clinical
() on the 2nd laboratory
() on 1.clinical
Question 541.
Patient, 32 years old. He complained of pain in the area of \u200b\u200bthe 11th tooth. On examination, no pathology of hard tissues was revealed. She has a history of mechanical injury. Choose which examination methods should be carried out:
(+) radiography
() odontoparodontogram
() masticiography
() rheography
() myography
Question 542.
Patient S., 27 years old, applied for prosthetics. Objectively: the height of the lower part of the face is not changed. The mucous membrane of the mouth is pale pink in color. Dental Formula: 870054321/12345 Select a provisional diagnosis from the following:
(+) Grade 3 according to Kennedy
() Grade 2 according to Kennedy
() Grade 1 according to Kennedy
() Grade 4 according to Kennedy
() Grade 5 according to Kennedy
Question 543.
Question 544.
Determine which designs belong to microprostheses:
() artificial crowns.
() bridges.
() dental implants.
Question 545.
A 40-year-old patient has no coronal part on the 23rd tooth, which method of making a pin-stump construction is shown during subsequent coating with a translucent all-ceramic crown:
(+) one-piece metal pin-and-stump inlay
(a) fiberglass post and composite stump.
() standard anchoring titanium post and composite die.
() standard anchoring copper pin and composite stump.
() standard stainless steel anchor pin and composite die
Question 546.
Prosthetics for a 65-year-old female patient with removable dentures. Determine, when receiving wax bases with occlusal rollers from the dental laboratory, the doctor must check:
(+) the boundaries of the future prosthesis correspond to the boundaries of the wax base
() tightly the basis covers the plaster model
() the roller of the lower wax base should be located strictly in the center of the alveolar process
() the roller of the upper wax base should be located somewhat vestibularly from the center of the alveolar process
() the roller of the upper wax base should be located somewhat vestibularly from the edge of the alveolar process
Question 547.
In a 50-year-old female patient, impressions were taken with removable dentures. Select the quality criteria and requirements of the anatomical impression:
(+) all parts of the plaster cast fit snugly together. The impression clearly reflects the relief of the prosthetic bed, the transitional fold, the dentition, the contours of the interdental spaces and the necks of the teeth. The thickness of the casts from the sides and bottom of a standard spoon is 3-4 mm, the edges are even, rounded, the surface is without erosion and air cavities
() the impression well reflects the relief of the prosthetic bed, the necks of the teeth are clearly reflected. The thickness of the impression is more than 6mm. No pores and shells
() reflects the relief of the prosthetic bed, transitional folds. No pores, no air pockets, impression thickness 2 mm
() the impression clearly reflects the relief of the prosthetic field, the edges are even, rounded
() the impression folds well into a standard tray, displays the prosthetic bed. The edges are rounded, the surface is pore-free, protrudes 1.5-2.0 cm from the spoon
Question 548.
Determine, in a 35-year-old patient, the coronal part is destroyed by more than 55%, when preparing the tooth cavity under the tab, the fold is formed at an angle:
(+) 45 degrees
() 15 degrees
() 30 degrees
() 60 degrees
() 90 degrees
Question 549.
The patient applied for preparation, the sequence of clinical stages in the manufacture of metal-ceramic and metal-plastic crowns consists of:
(+) examination, anesthesia, preparation, impression taking, cap fitting, color determination, crown fitting, delivery
() examination, taking an impression, preparation, fitting the crown, determining the color, delivery
() impression taking, cap fitting, crown fitting, color determination, delivery
() tooth preparation, examination, cap fitting, shade determination, delivery.
() examination, crown fit, shade determination, cement fixation
Question 550.
Patient 35 years old, with prosthetics and fit. Correct position of the edge of the pressed crown on the tooth:
(+) sinks under the gum by 0.1-0.2 mm
() at the level of the anatomical neck of the tooth
() at the level of the clinical tooth neck
() sinks under the gum by 0.4mm
() sinks under the gum by 0.2-0.3mm.
Question 551.
A 50-year-old patient has prosthetics with a metal-ceramic crown, which laboratory methods for making a cap were used:
()stamping
() broach
()drawing
Question 552.
A 55-year-old patient with orthopedic treatment, for the manufacture of which orthopedic structures are used detachable combined models:
(+) for the manufacture of one-piece, porcelain, metal-ceramic, metal-plastic crowns, bridges
() for the manufacture of plastic crowns
() clasp prostheses
() stamped crowns from ATP, gold
() stamped stainless steel crowns
Question 553.
The patient suffered a myocardial infarction three months ago. Mobility of teeth 31, 32, 33, 41, 42, 43 - 2-3rd degree. Chewing teeth on the lower jaw are missing. Your orthopedic treatment plan. What kind of prosthesis:
(+) removable denture for the lower jaw
() therapeutic treatment of periodontitis
() splinting clasp prosthesis on the lower jaw
() a therapist's opinion on the state of health and the possibility of orthopedic treatment
() complex treatment: therapeutic + orthopedic (splinting clasp prosthesis)
Question 554.
In a 30-year-old patient during examination, which anatomical landmarks of the teeth fix the interalveolar distance in orthognathic bite:
(+) palatine tubercles of the upper and buccal tubercles of the lower lateral teeth
() cheekbones of the upper and lower lateral teeth
() palatine and lingual chewing tubercles of the upper and lower lateral teeth
() buccal tubercles of the upper and lingual tubercles of the lower lateral teeth
() incisal edges of upper teeth
Question 555.
A 45-year-old patient in the absence of incisors and canines complains of:
(+) for an aesthetic defect, speech impairment, inability to bite off food
() on impaired speech, sinking cheeks, impaired chewing
() for an aesthetic defect, violation of food intake, for the formation of a jam in the corners of the mouth
() for pain in the temporal - mandibular joints
() the inability to bite off food
Question 556.
In a patient at an orthopedic appointment, the first clinical stage of manufacturing a metal-ceramic crown consists of:
(+) examination, diagnosis, choice of design, anesthesia, preparation, formation of a ledge, retraction of the periodontal edge, removal of a two-layer impression
() examination, diagnosis, selection of a prosthesis design, tooth preparation, anesthesia, removal of a double-layer impression
() making a diagnosis, choosing a design, anesthesia, preparing a ledge, taking a two-layer impression
() examination, diagnosis, choice of design, formation of a ledge, preparation of a tooth, retraction of the periodontal edge, taking an impression
() examination, impression taking, tooth preparation
Question 557.
Patient 50 years old with noble prosthetics. The first clinical stage of manufacturing a crown from a gold alloy, ATP:
(+) examination, diagnosis, treatment plan, choice of design, anesthesia, tooth preparation, taking an impression in the bite, registration of a medical history, dress
() examination, diagnosis, tooth preparation, impression taking, registration of medical history, dress
() examination, anesthesia, tooth preparation, choice of design, impression taking, registration of a medical history
() examination, taking an impression in the bite, preparation of the tooth, dressing, medical history
() making a diagnosis, making a medical history, taking an impression in the bite
Question 558.
When choosing instructions for patients of 47 years old, taking into account the construction material, the most consistent with the abrasion of the enamel of natural teeth:
(+) composite
() acrylic plastic
Question 559.
For orthopedic treatment in a 54-year-old patient and choosing a clasp prosthesis, the attachment must be installed:
(+) in parallelometer
() in the articulator
() in the occluder
() on a plaster model
() on a refractory model
Question 560.
In a patient of the orthopedic stage of treatment of patients during orthopedic treatment, it is recommended with a localized form of pathological abrasion of the teeth to apply:
(+) plastic mouthguard
() plate with an inclined plane
() plate with a vestibular arch
() bite pad
() plastic crown
Question 561.
In a patient with prosthetics, the shape of the intermediate part of the bridge on the anterior segment of the dentition:
(+) tangent
() tangent and flushing
() depends on the condition of the gums
Question 562.
In a patient before prosthetics, before taking impressions, the classification of impression materials depending on their physical condition after curing:
(+) elastic, thermoplastic, solid crystalline
() hydrocolloidal, reversible, irreversible
() solid crystalline, silicone, thiokol
() hard crystalline, elastic, reversible
() hard crystalline, rubbery, hydrocolloidal
Question 563.
At what defect of the occlusal surface of the coronal part of the tooth (index IROPZ, according to V. Yu. Milikevich) is it shown to use an artificial crown:
(+) IROPZ - 0.6 (60% destruction)
() IROPZ - 0.3 (30% destruction)
() IROPZ - 0.4 (40% destruction)
() IROPZ - 0.2 (20% destruction)
() IROPZ - 0.8 (80% destruction)
Question 564.
What designs belong to microprostheses:
(+) inlays, veneers, half crowns.
() artificial crowns.
() bridges.
() dental implants.
() adhesive bridges
Question 565.
The cast is
(+) negative image of the tissues of the prosthetic bed and adjacent areas
() a positive image of the relief of the tissues of the prosthetic bed and adjacent areas
() imprint of the chewing surfaces and incisal edges of the teeth to the equator
() reflection of moving tissues of the prosthetic bed
() impression taken under continuous pressure to compress the vessels of the mucous membrane
Static methods for determining chewing efficiency are used during direct examination of the oral cavity, when the state of each tooth and all available ones is assessed and the data obtained are entered into a special table, in which the share of participation of each tooth in the chewing function is expressed by the corresponding coefficient. Such tables have been proposed by many authors, but in our country they often use the methods of NI Agapov and IM Okksman.
In the table of NI Agapov, the lateral incisor of the upper jaw is taken as a unit of functional efficiency (Table 4).
In total, the functional value of the dentition is 100 units. The loss of one tooth in one jaw is equated (due to the dysfunction of its antagonist) to the loss of two teeth of the same name. Table 4 (according to NI Agapov) does not take into account the wisdom teeth and the functional state of the remaining teeth.
Teeth ratios tableN.I. Agapov
|
Upper and lower teeth |
Amount in units |
|||||||
|
Coefficients (in units) |
||||||||
I.M. Oksman proposed a table for determining the chewing ability of teeth, in which the coefficients are based on taking into account anatomical and physiological data: the area of \u200b\u200bthe occlusal surfaces of the teeth, the number of tubercles, the number of roots and their sizes, the degree of atrophy of the alveoli and the endurance of teeth to the vertical pressure, periodontal condition and reserve forces of non-functioning teeth. In this table, the lateral incisors are also taken as a unit of chewing efficiency, the wisdom teeth of the upper jaw (three-tuberous) are estimated at 3 units, the lower wisdom teeth (four-tuberous) - 4 units. The total is 100 units (Table 5). The loss of one tooth entails the loss of the function of its antagonist. In the absence of wisdom teeth, 28 teeth should be taken for 100 units.
Taking into account the functional efficiency of the chewing apparatus, a correction should be made depending on the condition of the remaining teeth. In case of periodontal diseases and teeth mobility of I or II degree, their functional value is reduced by a quarter or half. With the mobility of a III degree tooth, its value is zero. In patients with acute or exacerbated chronic periodontitis, the functional value of the teeth is reduced by half or equal to zero.
In addition, it is important to consider the reserve forces of the dentition. To take into account the reserve forces of non-functioning teeth, an additional fractional number should be noted for the percentage of loss of chewing ability on each jaw: in the numerator - for the teeth of the upper jaw, in the denominator - for the teeth of the lower jaw. An example would be the following two dental formulas:
80004321
87654321
12300078
12345678
80004321
00004321
12300078
12300078
With the first formula, the loss of chewing ability is 52%, but there are reserve forces in the form of non-functioning teeth of the lower jaw, which are expressed when the loss of chewing ability for each jaw is denoted as 26/0%.
With the second formula, the loss of chewing ability is 59% and there are no reserve forces in the form of non-functioning teeth. The loss of chewing ability for each jaw separately can be expressed as 26/30%. The prognosis of functional recovery with the second formula is less favorable.
To bring the static method closer to clinical diagnosis, V.K. Kurlyandsky proposed an even more detailed scheme for assessing chewing efficiency, which was called odontoparodontogram. A periodontogram is a schematic drawing in which data is entered about each tooth and its supporting apparatus. Data in the form of symbols obtained as a result of clinical examinations, X-ray examinations and gnatodynamometry, are entered into a special diagram-drawing.
2. Memod Oxman:the determination of chewing efficiency is based on the anatomical and physiological principle. Each tooth is assessed, including the wisdom tooth. This takes into account the area of \u200b\u200bthe chewing or cutting surface, the number of tubercles, roots, features of the periodontal tooth and the place of the latter in the dentition. The lower and upper lateral incisors, as functionally weaker, are taken as a unit. THEM. Oksman recommends considering the functional value of the tooth due to periodontal damage. Therefore, with mobility of the first degree, the teeth should be considered as normal, with the second degree, the percentage value is reduced by half, with mobility of the third degree, they should be considered absent. Single-rooted teeth with severe symptoms of apical chronic or acute periodontitis are assessed as missing. Carious teeth subject to filling are considered complete, and those with a destroyed crown are absent. Positive points: the functional value of each tooth is taken into account, not only in accordance with its anatomical and topographic data, but also functional capabilities.
Chewing coefficients of teeth according to I.M. Oksman
3. V.Yu. Kurlyandskyproposed a static system for recording the state of the supporting state of the teeth, named by him parodonmogram.
The periodontogram is obtained by entering the data record about each tooth in a special drawing. Each tooth with a healthy periodontium was assigned a conditional coefficient based on Haber's gnatodynamometric data. The more pronounced the atrophy, the more the periodontal endurance decreases. Therefore, in the periodontogram, the decrease in periodontal endurance is directly proportional to the loss of the tooth socket. Correspondingly, the coefficients of periodontal endurance to chewing pressure were established for various degrees of atrophy of the hole. The degree of atrophy of the hole is determined by X-ray and clinical studies. Since atrophy is often uneven, the most pronounced changes are taken into account. The following degrees of hole atrophy are distinguished: 1 degree - atrophy by 1/4 of the length of the hole, II degree - by 1/2, III degree - by 3/4, IV degree - the tooth must be removed.
Disadvantage of the method: Haber's data take into account only the endurance of the periodontium to vertical load, the endurance coefficients have significant variability, the decrease in endurance is not directly proportional to the degree of atrophy of the hole, the ability of the periodontium to perceive chewing pressure at different levels of the root is not the same.
Functional methods allow you to get the most correct idea of \u200b\u200bthe violation of the chewing function and its restoration after prosthetics.
Gelmanin 1932, he took as a food irritant several grains of almonds weighing 5 g and offered the patient to chew for 50 seconds the remainder was sifted through a series of sieves. The last sieve had round holes with a diameter of 2.4 mm. The remaining mass was carefully weighed. The proportion was calculated true loss of chewing. For example, 5 g - 100%; 2.5 g - X% (sieve residue).
Loss of chewing efficiency 50%. Hence, the chewing efficiency is 50%.
Ru6inov(1956) for testing suggests the patient chew a hazelnut weighing 800 mg until the swallowing reflex appears.
The method for determining the remainder and calculating the percentage of loss of chewing efficiency is the same as that of Gelman. When calculating, take into account the weight of the residue and the chewing time. Studies have shown that with orthognathic bite and intact dentition, the nut kernel is completely chewed in 14 seconds. As teeth are lost, the chewing time lengthens; at the same time the residue in the sieve increases.
4. Functional tests in diseases of the temporomandibular joint and malocclusion pathology.
5. Study of chewing pressure - gnatodynamometry.
6. Graphic methods for studying the chewing movements of the lower jaw (masticiography).
7. Study of the function of the masticatory muscles (myotonometry, electromyography, etc.).
8. General clinical tests (blood, urine, saliva, blood for sugar, etc.).
9. Allergic methods include:
1) allergic history;
2) skin allergy tests;
3) laboratory methods of specific allergy diagnostics.
10. Morphological, cytological, bacteriological and immunobiological research methods.
Making a preliminary and final diagnosis.
The diagnosis made reflects the essence of the disease, and includes the following sections:
1) morphological changes (classification of defects in the dentition, jaws, type of mucous membrane, etc.);
2) functional part (chewing efficiency in%);
3) complications resulting from morphological changes (decrease in the height of the lower third of the face, deep incisal overlap, displacement of the midline, local form of pathological abrasion, seizures, gingivitis, etc.);
4) concomitant diseases, those that will affect the dental status: allergic background, endocrine pathology, diseases of the musculoskeletal system, etc.).
Treatment plan.
1. Preparation of the oral cavity for prosthetics:
General sanitation measures are mandatory for all patients: removal of dental plaque; removal of the roots of teeth, with the exception of those that can be used in further prosthetics; removal of teeth that cannot be treated, which are foci of chroniosepsis; with mobility PIdegrees - all teeth, P degree - on the upper jaw. On the lower jaw, teeth with P the degree of mobility can be left;
Special therapeutic - depulpation of teeth, replacement of metal fillings;
Surgical - removal of exostoses, resection of the hypertrophied alveolar process, elimination of the palatine torus, elimination of cicatricial cords of the mucous membrane, plastic of the bridle, deepening of the vestibule of the oral cavity, resection of the apex of the tooth root, removal of significantly protruding teeth, implantology, etc.
Orthopedic elimination of secondary deformations of the occlusal surface by grinding, restructuring of the myotatic reflex, etc.;
Orthodontic preparation of the oral cavity - elimination of secondary deformities using special devices.
2. Type of prosthetics:
Orthopedic construction formula;
Therapeutic measures.
Orthopedic Treatment Diary.
All visits to the patient are recorded, indicating the date and a detailed description of the clinical procedures during repeated visits after the prosthesis is applied, they describe the complaints, objective examination data, the nature of the assistance provided and the patient's habituation to the prosthesis, an assessment of the nearest results of prosthetics is given.
Epicrisis and prognosis of orthopedic treatment.
1. Indicate the full name, age, patient complaints on the day of the visit to the clinic. Preliminary diagnosis. Start and end of treatment. The design of the prosthesis. The patient's condition as a result of treatment is described and the prognosis is indicated.
The period of follow-up examination of the patient (after 30 - 40 days) in order to check the long-term results of treatment.
2. An outpatient card is a mandatory legal and medical document, in which survey data, diagnosis, orthopedic treatment plan and recommendations, and their implementation are entered. All data must be recorded sequentially and in full. An outpatient card is a legal document and plays an important role in resolving various conflict situations and in investigative practice.
3. Deontology (from the Greek. Deon, deontos - duty, due, logos - teaching) is the science of the professional duty of medical workers. Medical ethics, which studies the moral and ethical aspects of medicine, is close to medical deontology. The success of treatment largely depends on the psychological state and attitude of the patient. Clinical actions of a doctor must comply with the medical commandment: "Do no harm." Mental shocks are remembered by the patient much stronger than the unprofessionalism of the doctor. Negative impressions about the doctor and about medicine in general remain with the patient for many years, and sometimes it is very difficult to deal with these prejudices. Positive results of treatment are largely determined by the patient's favorable attitude to the doctor, his confidence in the correctness of the chosen treatment. There are generally accepted norms of behavior for a medical worker in a clinic:
1) a polite and respectful attitude towards colleagues and patients. Maximum attention, goodwill, patience and caution when talking with patients;
2) preservation of medical confidentiality;
3) certain requirements for appearance: a clean, ironed white coat, change of shoes;
4) modesty in make-up, hairstyle, moderate use of perfumes, jewelry;
5) compliance with certain sanitary and hygienic standards (changing a glass in the presence of a patient, washing hands after sitting a patient in a chair).
When receiving a patient, all conversations on extraneous topics with colleagues and staff are prohibited in his presence. When talking with a patient, you should endear him to yourself, instill in him confidence in success and eliminate feelings of anxiety and fear. You need to talk with the patient confidently but delicately, directing the conversation in the right direction and focusing on the questions of interest. It is necessary to take into account the personality traits of each patient, the type of higher nervous activity and individual behavioral reactions. A good doctor is always a good psychoanalyst and actor. It is advisable that the patient starts and ends treatment with one doctor, the replacement of the doctor is carried out only when necessary (illness, dismissal).
The patient should feel comfortable. Soundproofing of the waiting room is required.
In the course of the work of medical workers, medical errors can occur that arise as a result of delusion and are most often the result of insufficient medical experience or are caused by an atypical course of the disease. It is necessary to distinguish from them medical offenses that are associated with improper (most often negligent, negligent) performance of duties, failure to provide assistance to the patient without a valid reason, receipt of illegal remuneration, violation of storage and accounting of strong, poisonous and narcotic drugs, disclosure of medical secrets, which entailed a moral and physical suffering of the patient.
Chewing activity is an important indicator of the condition of the dentition. This is the strength of the chewing muscles of the lower jaw, which is necessary for biting off, crushing and crushing food. It is measured on separate segments of the dentition.
Gnatodynamometry is a method of measuring the pressure of the muscles of the chewing apparatus, as well as the resistance of dental tissues to the force of compression of the jaws.
This technique is implemented through a device called a gnatodynamometer.
Most authors working on this topic took the chewing force of the weakest tooth as a unit. And the pressure of other teeth was determined in comparison with it. When calculating the chewing pressure constant, the author was guided by the following anatomical features of the tooth:
- surface dimensions;
- number of roots;
- the presence of bumps;
- interval from the angle of the lower jaw;
- cross section of the neck;
- features of the periodontium.
Research procedure
The measurement of chewing tension can be carried out using an electronic gnatodynamometer Rubinov and Perzashkevich. Into it 
includes special sensors built into the measuring head of the removable nozzle. There is a brass plate in the sensor connected to the microammeter.
The patient is comfortable in the chair. The absence of psychological stress is required. A nozzle is inserted into the mouth between the jaws and compressed by the teeth until painful sensations appear. The scale of the device at this moment displays the pressure. The indicators are recorded.
On the practical importance of indicators
Gnatodynamic indicators depend on many factors:
- the gender of the person;
- individual characteristics;
- diseases (, and others);
- partial loss of teeth;
- age.
Indicators on the device are displayed in kilograms. The average data ranges from 15-35 kg for the anterior and 45-75 kg for molars. They are essential for optimizing the prosthetic process, as they reveal the sensitivity of the periodontium to functional stress, helping to determine the design of the required prosthesis.
The average values \u200b\u200bof chewing pressure were determined, taken as the basis for measurements and correspondence of the load of periodontal endurance:
- on incisors in women - 20-30 kg;
- on molars in women - 40-60 kg;
- on incisors in men - 25-40 kg;
- on molars in men - 50-80 kg.
Chewing pressure on each tooth in kilograms
There are tables from different authors with the distribution of chewing force for each tooth, all of them are also approximate. The endurance of the periodontal tissue as a whole (1408 kg for men and 936 kg for women) is practically never realized, because the greatest power of contraction of the chewing apparatus is 390 kg.
Gnatometry is rarely used in modern dentistry due to the following disadvantages:
- only vertical pressure is measured without taking into account the horizontal force;
- the results are not completely accurate;
- there is a rapid deformation of the spring;
- in addition, the results are also determined by the psychosomatic state, which even in the same person changes during the day.
It is interesting to know what will happen if you do not replace the missing chewing teeth with prostheses:
Pages of history
Chewing power began to be measured as early as the 7th century. The famous anatomist and physiologist of the time, Giovanni Borelli, is considered the first to undertake such attempts. His method is pretty simple. A kettlebell was attached to a rope tied to the lower tooth, causing muscle resistance. The limits of the weight of the weights were equal to 200 kg. The disadvantage of this method is that the work of the muscles of the cervical muscles, which also took part in the resistance, was not taken into account.
The next innovator in this area was Black at the end of the 19th century. He is considered the first author of the gnatodynamometer. The first device consisted of two plates with a spring between them and resembled a mouth expander. The device was improved in 1919 by Haber, and in 1941 by M.S. Thyssenbaum. In these devices, only the vertical chewing load was determined.
In 1948, Kleitman I.A. designed a dynamometer that also experiences horizontal pressure. Instrument designs are being improved to this day. Devices are electronic, photometric, mechanical.
Agapov N.I. based on calculating the strength of each of the teeth as a percentage of the entire chewing apparatus. 
As a rule, a general count of the number of teeth is used to assess disorders of the chewing apparatus. Agapov considers this to be fundamentally wrong. After all, their power and effective value is different. He developed a table that distributes the coefficients between the teeth.
An important amendment is his conclusion that teeth are effective only in pairs. The teeth that have lost their antagonists are practically deprived of their main function. Therefore, in the absence of one tooth, the absence of two is stated. And the calculation of chewing activity, respectively, should be carried out by the number of paired teeth. When using this correction, the values \u200b\u200bare completely different.
Oxman amendments
In turn, Oksman I.M. indicates the importance and necessity of taking into account the activity of the remaining teeth in accordance with their mobility. At the first degree of pathological tooth mobility, chewing activity corresponds to 100%. In the second degree - 50%, and in the third - the absence of chewing activity is stated. The affected teeth also belong to the third degree.
Oksman, taking into account the development of Agapov, introduced the recording of antagonist teeth in the form of a fraction. The numbers denoting the loss of chewing activity are written in the following order: in the numerator - the maxillary indicator, in the denominator - the mandibular. According to this scheme, it is more convenient for the doctor to imagine the condition of the dentoalveolar apparatus.
Gnatodynamometric data are important in and with. Their value is influenced by: psychological experiences, compensatory abilities of periodontal receptors, measurement reactivity and numerous other factors.
By means of gnatometry, the following is carried out: measuring the force of pressure between pairs of teeth, assessing the functionality of prostheses, tracking the dynamics of therapeutic measures and the functionality of implants.
Before starting to study the question of methods of measuring chewing efficiency, it is necessary to understand four concepts that are often confused: chewing strength, chewing efficiency, chewing pressure and chewing power. Chewing force is called in physiology the force that can be developed by all the chewing muscles that raise the lower jaw. It is equal, according to Weber, on average 390-400 kg [the physiological diameter of all three pairs of muscles of the lower jaw lifters is 39 cm 2 (m. Temporalis \u003d 8 cm 2, m. Masseter \u003d 7.5 cm 2, m. Pterygoideus medialis \u003d 4 cm2, and 1 cm2 of the physiological area of \u200b\u200bthe muscle can develop a force of 10 kg; therefore, all lifters can develop a force of 390-400 kg).
Dentists, however, are not interested in the absolute, not the potential strength that can be developed by the chewing muscles, but in the strength that the chewing muscles develop during the chewing function. The chewing value of the dentition cannot be measured in kilograms. It can be determined in comparative terms by the degree of crushing of food. The degree of grinding to which food is brought by the dentition during the chewing function is called chewing efficiency. S. E. Gelman uses instead of the term "Chewing efficiency" the term "chewing power". But power in mechanics is the work done per unit of time, it is measured in kilogram meters. The work of the chewing apparatus can be measured not in absolute units, but in relative ones - by the degree of crushing of food in the oral cavity in percent. Therefore, the result of the work of the chewing apparatus per unit of time in percent cannot be called chewing power; it would be more correct to call it chewing efficiency. Chewing efficiency is measured as a percentage compared to an intact dentition, where the chewing efficiency is taken as 100%.
In dentistry (at the suggestion of Prof. SE Gelman) the term "chewing pressure" is used. SE Gelman calls the chewing pressure that part of the chewing force that can be realized only in one part of the dentition. Chewing pressure is measured in kilograms using a gnatodynamometer.
Gnathodynamometry
Chewing force was measured as early as the 17th century. In 1679 Borelli wrote about the following method of measuring chewing force. He put a rope on the lower molar, tying its ends, and hung weights from it, thus overcoming the resistance of the chewing muscles. The weight of the weights pulling the lower jaw down was equal to 180-200 kg. This method of measuring the chewing force is very imperfect, since it did not take into account that not only the chewing, but also the cervical muscles took part in holding the load. Bleck, MS Thyssenbaum proposed a gnatodynamometer for measuring chewing pressure (Fig. 47). This apparatus usually resembles a rotary dilator: it is equipped with two cheeks, sliding apart by a spring. The spring moves the arrow along a scale with divisions, depending on the force of closing the dentition; the arrow shows more or less chewing pressure. Recently, an electronic gnatodynamometer has been developed (Fig. 48).
Gnathodynamometry has the disadvantage that it only measures vertical pressure, and not horizontal pressure, with which a person crushes and grinds food. In addition, the device does not give accurate measurement results, since the spring quickly deteriorates. Some proponents of gnathodynamometry have established, through numerous measurements, the average values \u200b\u200bof the chewing pressure for the teeth of the upper and lower jaws (Table 4).
However, these numbers, just like others obtained by gnatometry, cannot be used as typical indicators, since the magnitude of the chewing pressure, expressed in kilograms, depends on the psychosomatic state of the patient during the test, and this state is different for different persons and even in the same persons at different times. In addition, gnathodynamometry has other disadvantages as well. Consequently, the given values \u200b\u200bare not constant, but variable, which explains the sharp discrepancy in the results of measuring the chewing pressure according to different authors.
Static methods for determining chewing efficiency according to N.I. Agapov and I.M. Oksman
As a result, many authors began to work on establishing constant values \u200b\u200bfor determining the chewing pressure of teeth. For this purpose, the authors used a comparative technique for measuring chewing pressure. Taking the chewing pressure of the weakest tooth, that is, the lateral incisor, as a unit of measurement, they compared the chewing pressure of the remaining teeth with it. This yields values \u200b\u200bthat can be called constants, since they are constant. The authors, with their method, were guided by the anatomical and topographic features of this tooth - the size of the chewing or cutting surface, the number of roots, the thickness and length of these roots, the number of tubercles, the cross-section of the neck, the distance of the teeth from the angle of the lower jaw, the anatomical and physiological features of the periodontium, etc. etc.
NI Agapov took the chewing efficiency of the entire chewing apparatus as 100% and calculated the chewing pressure of each tooth in percent, having obtained the chewing efficiency by adding the chewing coefficients of the remaining teeth (Table 5).
To get an idea of \u200b\u200bthe disorders of the chewing apparatus, the number of teeth is usually counted. This technique is incorrect, since it is not only a matter of the number of teeth, but also their chewing value, their importance for chewing function. The table of chewing coefficients of teeth makes it possible, when taking into account the loss of chewing efficiency, to get an idea not only about the number, but also to some extent about the chewing coefficient of teeth. However, this technique needs to be revised. This amendment was made by N.I. Agapov. When calculating the chewing efficiency of the impaired dentition, only teeth with antagonists should be taken into account. Teeth that have no antagonists have almost no meaning as organs of chewing. Therefore, the count should not be by the number of teeth, but by the number of pairs of articulating teeth (Table 6).
This amendment is very significant and the use of this amendment gives completely different figures than the definition of chewing efficiency without this amendment. Example-Dental Formula:
Without correction, the chewing efficiency is 50%, meanwhile, when using the correction of N.I. Agapov, the chewing efficiency is 0, because the patient does not have a single pair of antagonizing teeth. IM Oxman offers the following chewing coefficients for the lost teeth of the upper and lower jaws (Table 7).
IM Oxman considers it necessary, in addition to the functional value of the lost teeth, to take into account the functional state of the remaining teeth. The functional state should be assessed by the tooth mobility. Teeth with abnormal mobility of the first degree are considered normal, the second degree - as teeth with only 50% chewing value, teeth with pathological mobility of the third degree, as well as multi-rooted teeth with acute periodontitis are considered absent. Caries that can be filled up should be considered complete.
According to NI Agapov, the absence of a tooth on one jaw is regarded as the absence of two teeth (the indicated tooth and the antagonist of the same name). Considering this, I. M. Oksman proposes to record in the form of a fraction: in the numerator, a number is written indicating the loss of chewing efficiency in the upper jaw, and in the denominator, a number indicating the loss of chewing efficiency in the lower jaw. This designation of functional value gives a correct understanding of the prognosis and outcome of prosthetics. The calculation of chewing efficiency according to I. M. Oksman is undoubtedly more expedient than according to N. I. Agapov, since according to this scheme the doctor gets a more complete picture of the state of the dentition.
Periodontogram of V.Yu. Kurlyandsky
V. Yu. Kurlyandsky proposed a static method for determining the functional state of the supporting apparatus of the teeth, which he called periodontogram. The periodontogram is obtained by entering information about each tooth and the endurance of its supporting apparatus (Table 8) in a special drawing with symbols.
The drawing consists of five lines. The third line contains the designations of each tooth (dental formula) in Arabic numerals. Two rows of cells above the dental formula are designed to record the state of the supporting apparatus of each tooth of the upper jaw, and two rows of cells under the dental formula are intended to record the state of the supporting apparatus of the teeth of the lower jaw (Table 9).
The periodontogram aims to enable the physician to compare the functional value of different groups of teeth in the upper jaw with the corresponding groups of teeth in the lower jaw. But this goal, unfortunately, is not achieved by the author of the periodontogram. Firstly, the author himself writes: "All the frontal teeth of the upper and lower jaw may not participate in the act of biting off food, as a result of which all the calculations given will not reflect the true force ratios between antagonizing groups of teeth when biting off food." Secondly, "in one case, the frontal teeth are used to chew food (in the absence of chewing teeth or their soreness), and in the other, the chewing teeth, mainly premolars, are used to bite off food." Consequently, already, according to the author himself, the periodontogram is unsatisfactory.
In addition, to determine the performance of each tooth, the author uses the Haber table, compiled on the basis of gnatodynamometry data. Meanwhile, gnathodynamometry is a vicious method for the following reasons:
1. Gnathodynamometry gives an idea only of the chewing pressure in the vertical direction and does not take into account the pressure in other directions, and also does not take into account the actions of other components that affect the chewing efficiency, namely the quantity and quality of saliva, the neuroglandular apparatus of the oral cavity, the chewing and mimic muscles, anatomical and physiological features of the language, etc.
2. When using gnathodynamometry, the chewing pressure of each tooth is measured separately, meanwhile the dentition "is not the sum of teeth, but the dental system, in which there is a close interdependence both between its individual elements and between each element and the entire system as a whole.
3. Gnathodynamometry does not take into account the individual characteristics of the dental system in various patients, but is a standard method, which contradicts the principles of Soviet medicine.
4. As for, in particular, the data according to Haber, this is the worst gnatodynamometric method, because the data he obtained is mythical (1408 kg) and in no way corresponds even to the average figures of the chewing efficiency of teeth. Thus, gnathodynamometry is not able to give a correct idea of \u200b\u200bthe state of intact teeth.
5. The situation is even worse when using the method of V. Yu. Kurlyandsky state of the supporting apparatus of teeth affected by periodontal disease. He suggests measuring the depth of the gingival pocket, but the depth of the gingival pocket is determined by measuring the deepest point of the pocket. Meanwhile, it is known that the depth of the pathological pocket is uneven and the general condition of the entire pocket cannot be determined in this way. In addition, it is known that for establishing the nature of atrophy, the expansion of the periodontal gap is of no less importance, and the measurement of the depth of the pocket does not give any idea about the latter.
6. In addition, it should be added that bone atrophy and the depth of the gingival pocket characterize the morphological features of the pathological process. Meanwhile, at the modern level of medical science, it is necessary to take into account not only morphological disorders, but also the functional state of tissues in the issue of diagnostics.
Thus, the unsatisfactory method of using the Haber chewing coefficients is aggravated by the use of an inadequate method for measuring the depth of the pocket, and the data obtained when using the periodontogram do not correspond to reality.
A dynamic method for determining chewing efficiency
For a correct judgment about the functional ability of the masticatory apparatus, a dynamic method is needed, that is, it is necessary to take into account all movements of the lower jaw and the state of all elements of the masticatory apparatus, "taking part in the act of chewing: neuroreflex connections, glandular and motor apparatus of the oral cavity, soft tissues of the oral cavity In addition, in the correct assessment of the state of the masticatory apparatus, the features of the dentition play a role: the ratio of the dentition, the ratio of the jaws, the intensity of chewing, depending on the number of chewing movements and the strength of the chewing pressure. The number of articulating teeth is especially important in the dynamics of the lower jaw.
The act of chopping food consists, as you know, of three points: cutting, crushing and grinding food. All this work is accompanied by profuse salivation. The completeness of mechanical processing depends on the number of articulating teeth during the movement of the dentition. With a large number of articulating teeth, food chopping is improved. Meanwhile, the degree of food grinding, depending on the number of articulating teeth and other specified factors that are important for the functional state of the dentition, can only be detected during chewing. Therefore, the most valuable method for measuring chewing efficiency in an intact dentition is the method of functional diagnostics of the chewing apparatus. This method can be performed using functional chewing test, masticiography, masticiodynamometry, myography and myotonometry. We will describe only the first two methods for determining chewing efficiency.
Functional chewing test according to S.E. Gelman
S.E. Gelman, who studied and modified the method of the functional chewing test according to Christiansen, found that persons with a full-fledged chewing apparatus, possessing one hundred percent chewing efficiency, chew 5 g of almonds well for 50 seconds, crushing them during this time until the chewed the mass after drying freely passes through a sieve with holes, the diameter of which is 2.4 mm. If there are defects in the dentition, the almonds are not completely crushed for 50 seconds and therefore only part of the chewed mass passes through the sieve. In this regard, SE Gelman offers the following method of functional chewing test. The patient is offered to chew 5 g of almonds for 50 seconds, then the patient spits out the whole mass (it is dried and sieved through a sieve with holes of 2.4 mm). If the mass of chewed almonds is sieved, this means that the chewing efficiency is 100%; if only a portion is sieved, the percentage loss in chewing efficiency can be calculated by assuming 1 g whole almonds for 20% loss in chewing efficiency (see "Determination of Functional Chewing Test"). To study the effectiveness of oral cavity sanitation or prosthetics, as well as the effectiveness of any prosthesis design, the method of functional diagnostics in the form of a chewing test is almost indispensable and should be widely implemented in practice.
Giving a chewing sample. Weigh 5 g of almonds or apricots. It is advisable to prepare weighed portions in advance. The subject sits down at a table on which there is a small porcelain cup and a glass of boiled water at room temperature (14-16 °). He is offered to take all 5 g of grains in his mouth and start chewing on a signal. After the word "start" the subject begins to chew the grains. The start of chewing is indicated by a stopwatch. After 50 seconds, a signal is given by which the subject stops chewing and spits out the entire mass into the cup, then he rinses his mouth and spits out water into the same cup. If the patient has removable dentures, they are removed from the mouth and rinsed over the same cup. 5-10 drops of a 5% solution of mercuric chloride are poured into a cup for disinfection. It is very important that there is a calm environment in the laboratory during the research. The subject should sit quietly, not rush, not be nervous. To do this, you must briefly inform him about the purpose of the sample and its duration.
Processing of the received sample. The chewed mass is filtered through cheesecloth. For this, a medium-sized glass or metal funnel (8-10 cm in diameter) is inserted into a glass hollow cylinder or into an ordinary bottle. A gauze square measuring 15 X 15 cm is moistened with water and placed on the funnel so that the gauze sags, and its free edges descend over the edge of the funnel. With the left hand, the gauze is pressed against the edge of the funnel, and the contents of the cup are poured onto the gauze with the right hand. If there is sediment at the bottom of the cup, pour some water into it, shake it and quickly pour it onto cheesecloth. During straining, the edge of the gauze should not go down into the funnel, since in this case part of the mass can slip into the lower vessel. If this happens, then you should straighten the edges of the gauze, fix it to the edge of the funnel, rearrange the funnel into another spare vessel and pour the contents of the first vessel into it. Taking into account the possibility of such cases, each chewing sample should be filtered over a completely empty, clean vessel.
After straining, the gauze with the remaining mass is placed in a medium-sized porcelain cup or on a tea saucer. To dry the mass, a cup with gauze is transferred to a water bath of an appropriate size, and in the absence of one, it is placed in a saucepan or a deep metal cup filled with water, the cup is put on fire. Drying in the cupboard; more painstaking; in addition, there is no guarantee against overdrying and charring of the mass, which can lead to a change in the shape and weight of the particles. When the entire mass is dry, the cup with gauze is removed from the water bath, placed on the table and the gauze is separated from the mass on its surface from the bottom of the cup, after which, with light movements of the hands, the entire mass is freely removed from the gauze into the cup. The latter is again put in a bath for some time to finally bring the sample to a dry state. Before the end of drying, the mass must be mixed several times with a porcelain or metal spatula. Use the same spatula to clean the mass from the bottom of the cup. The mass is considered finally dried if it does not stick together into a lump when kneading between the fingers, but easily crumbles. During drying, it is necessary to ensure that the water does not boil off in the water bath, as this can lead to overdrying or even charring of the mass.
A metal sieve with round holes with a diameter of 2.4 mm is used to sift the dried mass. Such holes of the same diameter in all directions are more accurate gauges than the square holes of the Christiansen sieves. The sieve can be prepared from any small aluminum or tin cup, in the bottom of which holes are drilled with a round bur with a diameter of 2.4 mm. The sieve is placed over some dry cup, the whole mass is poured into the sieve, lightly and, shaking, sift out all the finely chewed mass. Only particles with a diameter greater than the diameter of the holes remain on the sieve. Sifting must be done carefully, stirring the mass frequently, preferably with a wooden stick, so that all sufficiently chopped pieces pass through the holes. Part of the mass remaining on the sieve is carefully poured onto a watch glass and weighed to the nearest hundredth of a gram. To facilitate and speed up the work, you need to have a few pre-weighed watch glasses in stock. The resulting weight is converted to a percentage of the total standard weight (5 g) using a simple formula.
Physiological test according to I.S. Rubinov
IS Rubinov developed the following physiological tests for accounting for the effectiveness of the act of chewing. The subject is asked to chew one kernel of 800 mg (average nut weight) on a specific side until the swallowing reflex appears. The patient spits out the chewed mass into a cup, rinses his mouth with water and spits it out into the same cup. Subsequently, the mass is processed according to Gelman, i.e., washed, dried and sieved through a sieve with 2.4 mm round holes, the resulting residue is weighed. For the same purpose, he used rusk (500 mg) and a piece of soft bread weighing 1 g, equal to the volume of the nut kernel, and the time of chewing before swallowing these pieces was taken into account. Research data have shown that as the condition of the chewing apparatus deteriorates, the chewing time before swallowing lengthens and the size of the swallowed particles increases. For example, in adults with a full-fledged chewing apparatus, the duration of chewing one nut kernel before swallowing is on average 14 seconds, and the remainder in the sieve is 0. In the absence of 2-3 teeth on one side, the chewing time before swallowing one kernel is 22 seconds, and the remainder in a sieve is equal to 150 mg. With unsatisfactory full dentures, the chewing time of one nut kernel before swallowing is 50 seconds, and the remainder in the sieve is 350 mg. The difference in indicators is most pronounced when chewing a nut, weaker - when chewing breadcrumbs, and even weaker - when chewing soft bread.
I.S. Rubinov points out that the test with chewing one nut kernel before swallowing, in comparison with 5 g, consisting of several kernels, is closer to normal natural food irritation and allows taking into account the effectiveness of chewing in different parts of the dentition and individual groups of articulating teeth. The single core assay can also be used successfully to assess the percentage of chewing effect. The percentage is calculated as in the sample according to S.E. Gelman, i.e., the weight of the nut kernel refers to the remainder in the sieve, as 100: x.
If the patient is not able to chew the kernel of the nut, then a test with a biscuit can be used. The criterion for judging the effectiveness of chewing is the duration of chewing before swallowing (the time for chewing a biscuit before swallowing is on average 8 seconds). When chewing a biscuit, a complex complex of reflexes of the motor and secretory order is obtained. These reflexes operate from the moment a piece of food enters the mouth. In this case, the motor reflex is associated with crushing the biscuit, and the secretory reflex - with the release of saliva, which moistens and lubricates the rough particles of the biscuit before swallowing.
By helping to crush food substances, chewing movements increase the effect of saliva and promote the fastest formation of a lump and its swallowing. Observations of I. S. Rubinov showed that with the appearance of dry mouth after taking atropine, the chewing time before swallowing lengthens, and the size of the swallowed pieces increases.
Masticatiography according to I.S. Rubinov
I.S. Rubinov, studying the mechanism of reflexes carried out in the oral cavity, developed a graphical method for taking into account the motor function of the masticatory apparatus. With the help of special devices (masticiograph), all kinds of movements of the lower jaw are recorded on the tape of a kymograph or an oscilloscope. The curves can be used to judge the nature of the chewing movements of the lower jaw. This method is called by the author masticatiography (recording of chewing).
The essence of this method lies in the fact that with the help of a masticiograph, consisting of a rubber balloon and a plastic case, all possible movements of the lower jaw are recorded on a rotating kymograph tape by air transmission through the Marey capsule (Fig. 49).
Graphically, the normal intake of one piece of food before swallowing is characterized by five phases (Fig. 50). On a masticiogram, each phase has its own characteristic graphic picture.
Phase I - resting phase - before the introduction of food into the mouth. In this case, the lower jaw is motionless, the muscles are in a minimum tone, the lower dentition is spaced from the upper one at a distance of 2-3 mm. On the masticiogram, this phase is indicated by a straight line (I) at the beginning of the chewing period at the level between the base and the top of the wavy curve.
Phase II - the phase of introducing food into the mouth. This phase corresponds to the moment a piece of food is introduced into the mouth. Graphically, this phase corresponds to the first ascending knee of the curve (II), which begins immediately from the line of rest. The range of this knee is maximally pronounced, and its steepness indicates the speed of introduction of food into the mouth.
Phase III- the phase of the beginning of the chewing function, or the tentative phase. This phase begins from the top of the ascending knee and corresponds to the process of adaptation to chewing a piece of food and its further mechanical processing. Depending on the physical and mechanical properties of food, changes occur in the rhythm and range of the curve of this phase. At the first crushing of a whole piece of food with one movement (intake), the curve of this phase has a pronounced flat top (plateau), which turns into a gently sloping downward knee to the level of the rest line. With the initial crushing and squeezing of a separate piece of food in several steps (movements) by finding the best place and position for squeezing and crushing, corresponding changes in the nature of the curve occur. Against the background of the flat plateau (top), there is a number of short additional undulating rises located above the level of the rest line.
IV phase - the phase of the main chewing function. Graphically, this phase is characterized by the correct alternation of periodic chewing waves. The nature and duration of these waves in a normal chewing apparatus depends on the consistency and size of the piece of food. When chewing soft food, frequent, uniform rises and falls of chewing waves are noted. When chewing solid food at the beginning of the phase of the main chewing function, less frequent descents of the chewing wave are noted. The harder the food and provides more resistance, slowing down the moment of raising the lower jaw, the more sloping the downward knee. Then, successively ascents and descents of chewing waves become more frequent. The intervals between the individual waves (0) correspond to the pauses when the lower jaw stops during closure. The size of these intervals indicates the duration of the stay of the dentition in the closing stage. Closing can be at the contact of the chewing surfaces and without contact. This can be judged by the level of the location of the line of intervals or "closing loops", as they will be called below. The location of the "closing loops" above the level of the resting line indicates the lack of contact between the dentition. If the "closing loops" are located below the resting line, then this means that the chewing surfaces of the teeth are in contact or close to contact.
The width of the loop formed by the descending knee of one chewing wave and the descending knee of the other indicates the speed of the transition from closing to opening of the dentition. A sharp corner of the loop indicates that the food has been briefly compressed. An increase in this angle indicates a longer duration of food compression between the teeth. The straight platform of this loop indicates a corresponding stop of the lower jaw in the process of crushing food. The "closing loop" with a wavy rise in the middle (0) indicates the rubbing of food during sliding movements of the lower jaw. The graphical picture of the curve of the main phase of chewing function described above gives an idea of \u200b\u200bhow the successive compression and crushing of food and its grinding occurs.
V phase - the phase of the formation of a lump followed by swallowing it. Graphically, this phase is marked by a wavy curve with a slight decrease in the height of the swing of these waves. The act of forming a lump and preparing it for swallowing depends on the properties of the food. With soft food, a lump is formed in one go; with solid friable food, it is formed and swallowed in several steps. According to these movements, curves are recorded on a rotating kymograph tape. After swallowing the food lump, a new state of rest of the chewing apparatus is established. Graphically, this state of rest is represented as a horizontal line (1). It serves as the first phase of the next chewing period.
The ratio of the duration of the individual phases of the chewing period and the nature of the sections of the curve vary depending on the size of the food bolus, the consistency of the food, appetite, age, individual characteristics, the state of the neuroreflex connections of the masticatory apparatus and the central nervous system. When using the masticiography method, the appropriate recording apparatus should be used correctly, and the analysis of the curves should be based on an accurate knowledge of the physiological foundations of the masticatory apparatus.