PROPAEDEUTICS OF THERAPEUTIC DENTISTRY
MODULE № 1: “Structure of teeth and cavity preparation”
SUBSTANTIAL MODULE № 2: “Cavity preparation”
PRACTICAL LESSON № 15: “Features of preparation of class IV cavities byBlack”
Duration of lesson – 2 hours.
Carrying out place – phantom room of therapeutic dentistry department.
Equipment: guide lines, tables, slides, breadboard models and moulages of the teeth, portable dental drilling engine, handpieces, set of tools, stomatologic drills.
Purposeofpracticallesson:
General: to study features of class IV cavities preparation
Concrete:
- To know a procedure and technics of class IVcavities preparation;
- To be able to preparate of class IVcavities byBlack;
- To be able to select and use necessary instruments;
- The complication nobility at preparationof class IVcavities byBlack;
- To be able to explain features of class IVcavities preparation.
Tasks on forming of initial level of knowledge:
- To know macro-and microscopical structure of the anterior teeth.
- To know classification of dental caries.
- To know a concept of contact point.
- To know the general principles and stages of cavity preparation.
Tasks for the control of an initial level of knowledge:
Task / Level / Standards of answersWhat indications to restorationof defectsof IV class withcompositefilling materials? / І / a) destruction of tooth crown of more than 1/3
+ b) destruction of tooth crown no more than 1/3
c) destruction of tooth crown no more than 1/2
d) destruction of tooth crown more than 1/2
e) defect of crown of any sizes
TothefourthclassbyBlackcarrythecariouscavitieslocated: / І / + a) on proximal surfaces ofthe 11th and 21stteeth with involving cuttingedge
b) on proximalsurfaces of the 34th and 44thteeth withinvolving occlusal surface
c) simultaneously on both proximal surfaces of the 15th and 25th teeth
d) on proximal surfaces of the 11th and 21stteeth without involving cuttingedge
e) on proximal surfaces of the 15th and 25thteeth withoutinvolvingocclusal surface
Questions to be study on practical lesson:
- Stages of cavity preparation at class ІV cavities by Black.
- Choice of instruments for preparation at class ІV cavities by Black.
- Complications at cavity preparation at class ІV cavities by Black.
Organizational structure of lesson:
Organizational part / 2 min.The control of initial level of knowledge / 5 min.
Theoretical interrogation and discussion of questions on a theme of practical lesson / 15 min.
Demonstration of an evident material on a theme / 10 min.
Self work on theme mastering / 35 min.
The control of initial level of knowledge of the student and success estimation / 20 min.
Assignment for self work / 3 min.
The student should know:
1. Stages and features of preparation of the class ІVcavities by Black.
2. Procedure and techniques of preparation of the class ІVcavities by Black.
3. Choice of toolkit for preparation of the class ІVcavities.
4. Complications at preparation of the class ІVcavities, ways of their prevention and elimination.
The student should be able:
1. To preparate the class ІVcavities by different methods of access.
2. To pick up and use necessary toolkit at preparation of the class ІVcavities by Black.
3. To warn and eliminate possible complications at preparation of the class ІVcavities by Black.
4. To explain features of preparation of the class ІVcavities by Black.
Tasks for self-control of knowledges-abilities:
1 level of complexity (α= I)
1. Feature at stages of opening and expansion of the carious cavity of ІV class by Black is:
a) at cavities of the ІV class these stages are not spent
b) creation of additional area
c) the maximum conservation of tissues on vestibular surface
d) the maximum removing of the softened tissues
e) obligatory excising of a blind fossa
2. What from specified truly characterises the additional area at the fourth class?
a) its width is twice more than width of the basic cavity
b) angle between it and the basic cavity is right
c) its length is equal to length of the basic cavity
d) its depth on 1 mm above amelo-dentinal junction
e) its depth is twice less than depth of the basic cavity
2 level of complexity (α= II)
3. What indications to opening of the carious cavity of IV class by vestibular access?
a) small cavity in the presence of diaeresis and diastemas
b) extensive carious cavities with destruction of lingual wall
c) replacement of the old filling located on a vestibular surface
d) insufficient access to a cavity at the subsequent fillingwith insufficiently aesthetic materials
e) extensive carious cavities with destruction of vestibular wall
4. The incisor crown is damaged on 1/3, what additional measures can be used for improvement of filling fixation?
a) formation of divergent walls
b) formation of additional area
c) fixation of parapulpal pins
d) creation of flutes and notches in cavity walls
e) it is necessary to prefer other methods of crown restoration
3 level of complexity (α= III)
Task 1
The crown of 12th tooth is damaged on 1/3. What manipulation methods use at formation of atypical cavities?
Task 2
21 tooth is depulpated, the crown is damaged. Which additional facilities are possible to recommend for filling fixation?
Standards of answers|replies|:
1 level of complexity (α= I)
1. Correct answer: c).
2. Correct answer: b).
2 level of complexity (α= II)
3. Correct answers: c), e).
4. Correct answers: b), c), d).
3 level of complexity (α= III)
Task 1
At damaged crown of 12th tooth, preparate according to a principle of biological expediency. It is necessary to removethe excavation in mesio-distal direction in the form of area. If defect of an angle is small, the labial and lingual walls are kept, it is necessary to frame a groove also in the form of a platform, is perpendicular to cutting tooth edge. At this operation consider features of topography of the pulp cavity and carefully preserve a dentine. In a cavity it is necessary to frame excavations for parapulpal dentinal pins. Restore such cavities composite materials with use of special caps.
Task 2
If 21st tooth is depulpated and the crown is very damaged, forfilling fixation most often apply intrapulpal pin. Fix a pin in the root canal with phosphate-cement. Defect of a crown restore with restoration or artificial tooth with pin.
Tasks for self work:
1. To drawthe kinds of the class IV cavities by Black and stages of their preparation.