National medical university of LVIV department of therapeutic dentistry



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12. The wider entrance opening of the cavities on the contact surfaces is predefined:

A. By a character|nature| of direction of the enamel prisms

B. Belonging to|by| a certain|definite| group of teeth

C. By the activity of cariosity

D. By the remoteness of cariosity

E. There is no right answer


13. A caries on contact surfaces has a tendency to|by| overwhelming spreading:

A. On the masticatory surface of a tooth

B. Precervical area of the crown

C. Vestibular surface of the tooth

D. A+B

E. There is no proper answer|absent|



Reference Literature


  1. Nikolyshyn a.K. Therapeutic dentistry /A.K. Nikolyshyn: a textbook for the students of dental faculties of higher medical educational establishments of IV level of accreditation in two volumes, T.I.– Poltava: Divosvit, 2005.– 392 p.

  2. Atlas|satin| of microanatomy| of organs of oral cavity of /L.A. Lutsyk, V.F. Makeev, A.M. Yashchenko, O.E. Zavadka, Yu.V. Makeeva, Yu.Ya. Kryvko.– Lviv: Nautilius, 1999.– 208 p.

  3. Preclinical course of therapeutic dentistry: course of lectures|fabric| /L.O. Tsvykh, O.A. Petryshyn, V.V. Kononenko, M.V. Hysyk.– Lviv, 2002.– 159 p.

  4. The methodological manual for|by| practical of therapeutic dentistry /L.O.Tsvykh, O.A. Petryshyn, V.V. Kononenko, M.V. Hysyk.– Lviv, 2003.– 98 p.

  5. Dmitrieva AA. Therapeutic dentistry|.– M.: Medpress-inform, 2003.– 896 p.

  6. Pediatric dentistry (Editor prof|. L.O. Khomenko).– K.: Book plus, 1999.– 524 p.

  7. Tsarynskiy M.M. Therapeutic dentistry |.– Rostov.: Feniks, 2008.– 508 p.

  8. Therapeutic dentistry (Editor Yu.M. Maksymovskyj).– M.: Medicine, 2002.– 640 p.

Practical lesson No 13
Theme: Classification of the carious cavities after Black. Principles and mode of the classic cavity preparation.

Short description of a theme
A decay of teeth is a local pathological process, which shows up after their eruption whith the following demineralization, softening of hard tissues of a tooth with next formation of a cavity. Carious cavities can appear practically on every surface of a tooth, however more frequently – in fissures of the premolars and molars, on the contact surfaces and in precervical areas.

Their grouping that we name|call| classes, was offered at the beginning of|in the beginning of| the XXth century by G.V.Black. Black’s classification divides the carious cavities in accordance with their location|disposition| and anatomical group of teeth.

Class I ­– the carious cavities, located in fissures of the premolars and molars|, and also in natural | pits|hole| of the incisors and molars|.

Class II – the carious cavities|, located on the contact surfaces of the premolars and molars|.

Class III – the carious cavities|, located on the contact surfaces of incisors and canines without the damage of a cutting edge and the corner of the crown of a tooth|.

Class IV – the carious cavities|, located on the contact surfaces of incisors and canines with the damage of a cutting edge|place| and the corner of the crown of a tooth.

Class V – the carious cavities|, located in thr precervical areas in all groups of teeth.

In some|certain| American editions|publishment| it is possible to come across the additional VI class for cavities, located on cusps|hill| and cutting edges of all groups of teeth, in the so-called|so called| caries-resistant areas|zone|.

The preparation of the carious cavity – instrumental intervention on hard tissues of teeth, that consists of certain|definite| consistent manipulations. It is directed on the carving of pathologically changed hard tissues with the purpose of arresting the subsequent|consequent| progression of carious process, and also creation|making| the necessary conditions for the fixation of a filling and restoration of the anatomic form and function of a tooth.|renewal|

The preparation of the cavity is|appear| the important stage of treatment of tooth decay, because its correct performing eliminates|dismiss| the further|consequent| destruction of hard tissues and provides|secure| the reliable fixation| of the filling.

There are few|a little| principles of preparation of the carious cavities. Principle of “expansion|amplification| for the sake of prevention” (Black) is preventive expansion|amplification| of limits|border| of the carious cavity, by carving of caries-resistant| areas (fissures|, pits|hole|) to|by| the so-called|so called| immune areas|zone|, which are rarely|seldom| affected by caries (cusps|hill|, smooth and smooth protuberant surfaces).

Principle of „biological expedience” (I.G. Lukomskiy) – the tissues of a tooth are carved carefully and preparation is completed|end| within the limits of apparently healthy areas. Consequently|so|, the basic principle which is to be|what| followed while preparing the carious cavity is the complete carving of pathologically changed tissues and cautious attitude toward the non-affected by caries the enamel and dentine.

To attain the purpose, it is necessary while preparing the carious cavity:


  • to define the elements of the carious cavity and provide|secure| it|her| reliable healthy control;

  • to perform consistently all the stages of preparation;

  • to choose correctly the instruments for the formation of carious cavity|;

  • to follow the certain|definite| principles of preparing the carious cavity|: biological expedience, taking into account the limits|border| of expansion and topography of a cavity, technical rationality|.

While preparing the hard tissues of a tooth the classification of Black is usually used. However, regardless of localization of the carious cavity, there are the general|common| stages of preparing the hard tissues of a tooth, which|what| are as follows|by|:

  • anaesthetization;

  • opening|dissection| (opening and expansion|amplification|) of the carious cavity;

  • necrectomy|;

  • the cavity formation;

  • smoothing of the edges|place| of the enamel, finishing|.

The opening|dissection| of the carious cavity is carried out by|by means of| spherical or the fissure dental drills. They are selected so that the size|dimension| of working part|portion| was not larger, than the entrance opening of the present carious cavity.

The expansion|amplification| of a cavity is performed within the limits of the practically healthy, hard tissues of a tooth which are not affected by caries. During the expansion|amplification|, carving of decayed fissure is foreseen, alignment of the enamel edge|place|, round acute angles to prevent the origin of the second|secondary| caries.



Necrectomy  is an excision of the necrotic (carious) hard tissues. There are two types of necrectomy – complete and partial necrectomy. Complete necrectomy is the complete excision of the necrotic dentine from the walls and bottom of the carious cavity; partial necrectomy is the complete excision of necrotic dentine from the walls and partly – from the bottom of the carious cavity. Partial necrectomy is assumed in the case of deep caries, when the bottom of the carious cavity is very thin and there is the real danger of opening of the pulp. In such cases it is assumed to leave a dense pigmented dentine on the bottom, and in case of acute deep caries – even small layer of the softened dentine with further remineralization. Nekrectomy is carried out by spherical drill and excavator.

Formation of the carious cavity is carried out with the help of|implement| fissures|, inverted cones and cone-shaped drills.

Treatment of the edges|place| of the carious cavity is|appear| the final stage of formation|, which|what| is carried out by polirs. The enamel edge|place| must be formed according to|by| direction of enamel prisms.

Elements of the carious cavity: bottom, walls, corners, edges|place|. There are such concepts|notion|, as basic|main| and additional cavities: the first is made in place of pathological focus|, the second – within the limits of healthy hard tissues for the best fixation of a filling|.

The peculiarities of the formation of a cavity, mainly, depends from the localization of the pathological process and group belonging of a tooth. However there are general rules for preparing of all the cavities|, namely:

1) passing of a bottom of a cavity (surface, reverse|turned| to|by| the pulp) to the lateral wall must be at right angles;

2) passing of one wall to another must be under a corner (except for|unless| the cavities of the V class);

3) edges|place| of the enamel must be even|equal| and smooth;

4) a bottom of the carious cavity must be flat or to some extend repeat the form|shape| of the masticatory surface of a tooth|.

Each cavity out of five classes possesses its own peculiarities.



Control questions to|by| practical lesson |fabric|


  1. What is caries of a tooth?

  2. Name|call| the basic principles of the cavity preparation.

  3. What is the cavity preparation directed on?

  4. What is meant under “conception of Black”?

  5. Where are the caries-resistant| areas located?

  6. What is meant under the term “immune areas”|zone|?

  7. What is meant under the term “biological expedience”?

  8. Name|call| the stages of preparing of the carious cavities.

  9. Name|call| instruments|tool| which|what| are used|use| for opening of the carious cavity.

  10. Name|call| instruments|tool| which|what| are used|use| for expansion|amplification| the carious cavity.

  11. What is necrectomy|?

  12. What types of necrectomy do you know?

  13. What instruments|tool| are used in performing necrectomy|?

  14. What instruments|tool| are used for forming of the carious cavity?

  15. What instruments|tool| are used for smoothing of edges of the cavity|place|?

  16. Name|call| the basic|main| elements of the carious cavity.

  17. Name the general rules for the preparation of all carious cavities.



Situation tasks and test control
1. What signs are assumed as a basis in the classifications of the carious cavities after Black?

  1. Histological

  2. Clinical

  3. Topographical

  4. Anatomical-topographical|

  5. Clinical-topographical|


2. according to Black to|by| the III-rd class belong|behave| the carious cavities located on a surface:

  1. To the contact incisors

  2. Contact premolars|

  3. Precervical incisors

  4. Masticatory molars|

  5. Masticatory premolars|


3. The carious cavity, located on the distal contact surface of the 36th tooth, according to the classification of Black belongs to the class:

  1. I

  2. III

  3. II

  4. IV

  5. V


4. in accordance with the classification of Black to|by| the II-nd class belongs the carious cavities, located on|behave|:

  1. To the contact surface of canines|

  2. To the contact surface of molars|

  3. To the vestibular surface of molars|

  4. To the oral surface of incisors

  5. To the lateral surface of incisors


5. On what surfaces are the medio-occlusal-distal cavities formed?

  1. On the front and back contact

  2. On the occlusive and vestibular

  3. On the back contact with an additional site

  4. On the front contact with an additional site

  5. Contact with a general|common| additional site


6. The aim of purpose of odontopreparation|:

  1. A, B, C, D

  2. To carve the demineralized hard tissues of a tooth

  3. To create necessary conditions for the reliable fixation of a filling

  4. To restore the thread of an anatomic form|shape| and function of a tooth

  5. B, D


7. What is the first stage of preparing of the carious cavity?

  1. Antiseptic treatment

  2. Finishing of the enamel edges

  3. Opening|dissection| of the carious cavity

  4. Forming

  5. Necroctomy


8. The purpose of necrectomy in the prevertion of carious recurrence is|appear|:

  1. Warning of relapse|set-back| of caries

  2. Creation|making| of a contact point|station|

  3. Restoration of the shape|shape| of a tooth

  4. Restoration of the function of a tooth

  5. Defence|protection| of the pulp of a tooth


9. What dental instruments|tool| are used to determine the|definition| quality of preparing of carious cavity?

  1. Pluger, probe

  2. Probe, smoother|

  3. Pincers, mirror

  4. Probe, mirror

  5. Probe, pincers


10. What is the proportion between the basic|main| and additional cavities in preparing the II-nd class after Black?

  1. 1:2

  2. 2:1

  3. 2:3

  4. 3:1

  5. 1:3


11. Opening|dissection| of the carious cavity is conducted by the dental drill:

  1. Cylindrical

  2. Spherical

  3. Inverted-conical (cone-shaped)

  4. Whell-shaped

  5. Load-shaped


12. Necrotomy is conducted by:

  1. Fissura-shaped drill

  2. Whell-shaped drill and excavator

  3. Dental drill and excavator

  4. Carborundum

  5. Excavator


13. The cavity preparation on the masticatory surface of the 36th tooth you procced to its forming. Choose the dental drill for forming the enamel edge|place|:

  1. Spherical hard alloy|

  2. Spherical diamond

  3. Cone-shaped hard alloy

  4. Inverted cone-shaped diamond

  5. Cylindrical diamond


14. You are to prepare the carious cavity of the 1st class in a middle caries. Choose the dental drill for forming of its bottom.

  1. Spherical steel

  2. Inverted cone-shaped steel

  3. Cylindrical diamond

  4. Spherical steel

  5. Inverted cone-shaped hard alloy |


15. Which of the stages of preparing the carious cavity is conducted after necrectomy|?

  1. Forming the carious cavity

  2. Drug therapy

  3. Opening|dissection| of the carious cavity

  4. Expansion|amplification| of the carious cavity

  5. Imposition of insulating gasket


16. While reviewing|examination| the patient you reveals|expose| the carious cavity on the palatal surface of the 12th tooth. What class does it|her| belong|by| to after Black?

  1. 2nd class

  2. 3rd class

  3. 4th class

  4. 1st class

  5. 5th class



Reference literature


  1. Nikolyshyn a.K. Therapeutic dentistry /A.K. Nikolyshyn: a textbook is for the students of dental faculties of higher medical educational establishments of IV level of accreditation in two volumes, T.I.– Poltava: Divosvit, 2005.– 392 p.

  2. Borovskiy E.V. Therapeutic dentistry: a textbook is for the students of dental faculties of higher medical educational establishments.– M.: Med. Inform. agency, 2006.– 840 p.

  3. Nikolyshyn a.K. Therapeutic dentistry /A.K. Nikolyshyn: a textbook is for the students of dentistry faculties of higher medical educational establishments of IV level of accreditation in two volumes, T.IІ.–Poltava: Divosvit, 2007.– 280 p.

  4. Preclinical course of therapeutic dentistry: course of lectures|fabric| /L.O. Tsvykh, O.A. Petryshyn, V.V. Kononenko, M.V. Hysyk.– Lviv, 2002.–159 p.

  5. The methodological manual for|by| practical of therapeutic dentistry /L.O.Tsvykh, O.A. Petryshyn, V.V. Kononenko, M.V. Hysyk.– Lviv, 2003.– 98 p.

Practical lesson No 14
Theme: The peculiarities of the cavity preparation of the class I (Black classification).

Short description of a theme
The form of cavity of the class I is more often determined by the features of those natural sulci in which the carious has developed. It can be of cylindrical, diamond-shaped, five-pointed, cruciform. When there are two cavities, separated from each other by a small number of healthy tissues, they are united and prepared, as one cavity, but when there is a sufficient layer of intact tissues between them, than they are prepared separately.

While preparing the carious cavities in natural pits of the incisors |hole|, it should be kept in mind about the location|disposition| of the pulp. The newly formed cavity is of cylindrical shape|shape|.



Complications in preparing the carious cavities class I. Heavy complication is a perforation of the bottom of the carious cavity. More frequently it occures when the entrance into the carious cavity was not widened. Sometimes the reason of perforation are not precise manipulations by the drill or excavator. The second complication is a fracture of the wall of the carious cavity as a result of load-shaped motions by a excavator. The perforation of the wall of the carious cavity more frequently happens near the neck of a tooth; the main reason of such complication  is bad illumination of the operating field and lack of the experience of a doctor.
Control questions to|by| practical lesson


  1. What is caries, and its|its| classification?

  2. What carious cavities belong to|by| the cavities of the I class?

  3. Name|call| the elements of the carious cavity.

  4. How should the cavity of the class I be formed if there are two carious cavities closely placed on the masticatory surface of a tooth?

  5. How should the cavity of the class I be formed if there are two cavities on the same tooth localized on a masticatory surface and in the fissure of a buccal surface?

  6. Whether it is always needed to put a carious cavity into a masticatory surface, if it|her| is located on a buccal surface?

  7. What dental drills are used|use| for the formation of the carious cavity of the class I?



Situation tasks and test control
1. While reviewing|examination| the patient you reveal a carious cavity on the palatal surface of the 12th tooth. What class does it|her| belong|by| to after Black?

A. 1st class

B. 2nd class

C. 3rd class

D. 4th class

E. 5th class


2. You are to prepare the carious cavity of 1st class in the middle caries. Choose the dental drill for forming the bottom of the carious cavity:

A. Spherical steel

B. Spherical steel

C. Inverted cone-shaped steel

D. Cylindrical diamond

E. Inverted cone hard alloy


3. At the time of your practical training you help a doctor|physician| who|what| is preparing the carious cavity of 1st class in the 16th tooth. Choose a cutting instrument|tool| for conducting the stage of necrectomy|.

A. Hard alloy cyrindrical conical drill

B. Conical hard alloy dental drill

C. Cylindrical diamond dental drill

D. Exacavator

E. Whell-shaped hard alloy dental drill


4. On the masticatory surface of the 46th tooth in the area of fissures there are two carious cavities which are closely|near| located. How in this case should the preparation be conducted?

  1. To unite|combine| carious cavities into one

  2. To form two separate cavities

  3. To be of no importance

  4. Depends on stopping material|fabric| which|what| will be used in restoration

  5. Depends on the age of a patient


5. On the masticatory surface of the 17th tooth, two carious cavities are localized in the area of fissures|; there is a carious pigmentation of fissures|. How should the cavity preparation be conducted?

  1. Preparation of the carious cavities with carving of fissures|, carve the adjoining areas of cusps|hill| and form a large|great| oval cavity

  2. Both carious cavities are unite|combine| into one, fissures are left non-prepared

  3. Preparation of both carious cavities with carving of fissures|, while the adjoining healthy areas of the enamel are left non-prepared, the cross-shaped oval cavity is formed|shape|

  4. The carious cavities are prepared separately, the remineralizing therapy is conducted in fissures

  5. The carious cavities and fissures are prepared separately |


6. While reviewing|examination| the oral cavity of a patient, the carious cavity on the cheek surface of the 46th tooth was revealed. What class does this cavity belong to|behave||by| after Black?

  1. I

  2. II

  3. III

  4. IV

  5. V


7. On the masticatory surface of the molar there are two carious cavities, separated by thick rollers of healthy enamel. How should the carious cavities be prepared?

  1. To unite|combine| carious cavities into one

  2. To form two separate cavities

  3. Is of no importance

  4. Depends on stopping material|fabric| that will be used for restoration

  5. Depends on the age of a patient

8. During the cavity preparation on the masticatory surface of the 36th tooth you procced to its formation. Choose the dental drill for the formation of the enamel edge|place|:

A. Spherical carbid hard alloy

B. Cylindrical diamond

C. Spherical diamond

D. Cone-shaped hard alloy

E. Inverted cone-shaped diamond



Reference literature


  1. Nikolyshyn a.K. Therapeutic dentistry /A.K. Nikolyshyn: a textbook is for the students of dental faculties of higher medical educational establishments of IV level of accreditation in two volumes, T.I.– Poltava: Divosvit, 2005.– 392 p.

  2. Borovskiy E.V. Therapeutic dentistry: a textbook is for the students of dental faculties of higher medical educational establishments.– M.: Med. Inform. agency, 2006.– 840 p.

  3. Nikolyshyn a.K. Therapeutic dentistry /A.K. Nikolyshyn: a textbook is for the students of dentistry faculties of higher medical educational establishments of IV level of accreditation in two volumes, T.IІ.–Poltava: Divosvit, 2007.– 280 p.

  4. Preclinical course of therapeutic dentistry: course of lectures|fabric| /L.O. Tsvykh, O.A. Petryshyn, V.V. Kononenko, M.V. Hysyk.– Lviv, 2002.–159 p.

  5. The methodological manual for|by| practical of therapeutic dentistry /L.O.Tsvykh, O.A. Petryshyn, V.V. Kononenko, M.V. Hysyk.– Lviv, 2003.– 98 p.
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