This document provides an introduction to operative dentistry from Dr. Hazem El Ajrami. It defines operative dentistry and discusses its scope, objectives, and indications. Key topics covered include carious and non-carious lesions, tooth histology and occlusion considerations, cavity classifications and nomenclature, and cavity preparation fundamentals. Black's classification system for cavities is explained, detailing the 5 main classes of cavities. Walls and angles of cavities are defined, including the pulpal wall, axial wall, cavo-surface angle, dentino-enamel junction, enamel wall, and dentin wall. References on operative dentistry and preclinical course materials from Cairo University are also listed.

2. College of DentistryCollege of Dentistry
Operative Dentistry IOperative Dentistry I
IntroductionIntroduction
Dr. Hazem El AjramiDr. Hazem El Ajrami
Master Degree in Orthodontic & PedodonticMaster Degree in Orthodontic & Pedodontic

3. • Definitions,Definitions, Scope and Objectives of OperativeScope and Objectives of Operative
Dentistry.Dentistry.
• Carious & Non Carious Lesions.Carious & Non Carious Lesions.
• Tooth Histology, Form & Occlusion: OperativeTooth Histology, Form & Occlusion: Operative
Considerations.Considerations.
• Cavity Classifications & Nomenclatures.Cavity Classifications & Nomenclatures.
ContentsContents

4. • Fundamentals of Cavity Preparation.
• Instruments and Instrumentation.
• Intermediary Liners & Bases.
Contents

5. The References
1. Art and Science of Operative Dentistry.
2. Operative Dentistry Preclinical Course
(Cairo University).

6. Definitions, Scope and Objectives of
Operative Dentistry

7. • Definition:
Operative dentistry is that branch of
dentistry which based on art and
biomechanical science. It includes all
procedures whereby defects in hard tooth
substance are eliminated, their progress is
inhibited, recurrence is prevented and lost
tissues are skill fully reproduced. The tooth is
restored to normal bio-mechanical and esthetic
functions as healthy unit of the masticatory
system.

8. • Operative dentistry is that branch of dentistry
which deals with the esthetic and functional
restoration of the hard tissues of individual
teeth.

10. • Prevalence in U.S. population for 1988 to 1994
indicated that 45% of children (aged 5 to 17)
had carious teeth. In adults, almost 94% had
evidence of past or present coronal caries. Thus,
caries will be of major importance for the
foreseeable future.

11. • Scope:
Operative dentistry originally encompassed
the whole dentistry. However, in response to
extensive service demands and concurrent
innovative research and advances, other various
clinical branches emerged and became
recognized specialties. Operative dentistry
remains a core for clinical practice with a major
contribution to dental health service.

12. • Operative dentistry includes all procedures
necessary to eliminate the lesion, provide a
biomechanically compatible room for
accommodation and retention of a synthetic
restorative material for the lost tooth
structure. It is practiced in sequential phases
aiming to achieve total patient treatment rather
than a "drill and fill" policy.

13. • The first phase is concerned with diagnosis
and clinical assessment of the patient. This
includes all relevant information about the
patient, including age, occupation, general
health, dietary habits, caries activity, home-
care and socio-economic status. It also
involves identification of the type and extent
of the original insult of caries, erosion,
attrition, traumatic fracture, hypoplasia,
discoloration or changes of tooth form, size,
position, alignment or occlusion.

14. • The second phase is devoted to outlining the
treatment plan in logical sequential steps of
procedures. From the previous diagnostic
phase, selection of the appropriate restorative
material (s) is made and determination of any
possible cooperation of other allied disciplines
such as endodontics, periodontics,
orthodontics or maxillofacial surgery is
determined.

15. • The third phase concentrates on execution of
operative procedures to eliminate the lesion
and provide the necessary preparation that
accommodates the selected restorative
material.

16. • The fourth phase is the restorative phase which
is concerned with construction of the
restoration and application of cavity
liners/bases. The operative and restorative
procedures should be based on well
established scientific mechanical, biological
and esthetic fundamentals.

17. • The fifth phase deals with regular follow up
and maintenance of existing restorations and
the general health of the dentition. Preventive
treatment should be implicated and home care
encouraged.

18. • Objectives:
Restorative treatment is not limited to the
synthetic substitution of lost hard
tooth structure but it includes a program for
control of the attacking mechanism
with provisions for restoration of an integral
masticatory system to normal health,
functional efficiency and harmonious esthetics
and function. This is done through
application of accepted and cross-linked
biological, mechanical and esthetic basic
fundamentals.

19. I. Restoration of health for the affected tooth:
Operative dentistry involves preventive
and restorative methods for elimination of
the lesion and its influence, reproduction of
lost tooth structure and establishing full
control on the attacking mechanism.

20. • This objective requires:
 Complete elimination of defective tooth
structure.
 Preservation and protection of the remaining
tooth structure; this involves:
A. Mechanical protection of tooth structure
against fracture, including preparing
conservative cavity design with its margins
free from caries, discoloration, weakened
tooth structure and placed at areas of less
stress.

21. B. The restoration should be able to produce
and maintain a leak-proof
sealed margins which are cariostatic and
biologically compatible.
C. All operative and restorative treatments
should be biocompatible with
the pulp-dentin organ.

22. Application of an anti-caries program; the
patient should maintain good
oral hygiene and an anti-caries program should
be applied for protection against recurrence of
caries, including regular fluoride application
and correction of dietary habits.

23. II. Restoration of normal occlusion and efficient
mastication:
 Efficient mastication demands a restoration
which establishes and maintains proper
occlusal anatomy, axial contour and inter-
proximal contact without any occlusal
interferences or anatomic departures from
the normal anatomic landmarks.

24. In addition, the restoration should be form
stable, securely retained in place and
sufficiently strong to sustain the multiple types
of mastication forces without fracture,
distortion, loss of substance or change of
surface texture.

25. It should also be biocompatible with the tooth
structure with no irritation
on the adjacent or remote tissues of the
masticatory system including the
teeth, investing tissue, muscles of mastication
and TMJ.
The patient should be able to enjoy
comfortable mastication without problems of
food impaction, hypersensitivity or pain or
development of abnormal occlusal or biting
positions.

26. III. Restoration of esthetics:
 The demand for esthetic appearance of the
dentition is becoming a major
concern in the modern dentistry to the extent
that some patients give it priority to
physical properties if compromise becomes
necessary.

27.  Restoration of esthetics requires that the
defective tissues are eliminated and
reproduced to exact harmonious color, size,
form, translucency and surface texture with
correction of any minor abnormalities of
occlusion, alignment and inter-arch
articulation.

28. Indications
• The indications for operative procedures are
numerous. However, they can be categorized
into three primary treatment needs:
1. Caries.
2. Malformed, discolored, nonesthetic, or
fractured teeth.
3. Restoration replacement or repair.

31. • These operative and restorative procedures are
based on well established scientific
mechanical, biological and esthetic
fundamentals. Skillful application of these
principle fundamentals is essential for the
successful achievement of the objectives of
operative dentistry.

32. Cavity Classifications
1. Anatomical classification.
2. Black’s classification.
3. Numerical classification.
4. Mount’s classification.

33. Black’s Classification
The classification devised by G.V. Black,
which is based upon the site of onset of the
carious process, and the relative frequency of the
various sites involved, is most widely adopted.
Black classified cavities into five classes:

34. a) Class I Cavities:
Those cavities originating in anatomical pits
and fissures. They are found in the occlusal
surface of molars and premolars, the occlusal
two-third of the buccal and lingual surfaces of
molars and in the palatal surfaces of upper
incisors.

39. b) Class II Cavities:
Are smooth surfaces lesions that occur in
the proximal surfaces i.e., mesial or distal of
molars and premolars.

41. c) Class III Cavities:
These cavities occur in the proximal
surfaces (mesial and distal) of incisors and
canines; but do not involve or include the
incisal angle.

43. d) Class IV Cavities:
Cavities that originate on the mesial and
distal surfaces of incisor and canine teeth, but
caries is so extensive that the incisal angle is
involved.

45. e) Class V Cavities:
Are smooth surface cavities occurring in the
gingival third of the buccal and lingual surfaces
of all teeth, excluding cavities occurring in
anatomical pits in the palatal surfaces of upper
incisors, where they are grouped with Class I
cavity.

47. f) Class VI Restorations:
Restorations on the incisal edge of anterior
teeth or the occlusal cusp heights of posterior
teeth are Class VI (originally not included in
the classification).

49. Walls and Angles of Cavities

50. Black gave the following rules for naming
the internal parts of the cavities and stated:
“Students should not burden themselves with
memorizing these illustrations or lists, for, if
they know the rules and their application they
can make complete lists at any time”.

51. Rule I:
The surrounding walls of a prepared cavity
take the names of those surfaces of the teeth
adjoining the surface decayed, towards which
they are placed.

53. Rule II:
The wall of a prepared cavity, which is
occlusal to the pulp, and in a horizontal plane at
right angles to the long axis of the tooth, is
called the pulpal wall. In case the pulp of the
tooth is removed, and the cavity thus extended
to include the pulp chamber; that wall is called
the sub-pulpal wall.

54. Pulpal WallPulpal Wall

55. Rule III:
That wall of a prepared cavity in an axial
surface (parallel to the long axis of the tooth)
and approximates the pulp, is called the axial
wall.

56. Pulpal WallPulpal Wall
Axial WallAxial Wall

57. • Cavo-Surface Angle:
It is the angle formed by the junction of the
wall of the cavity with the surface of the tooth.
The cavo-surface angle of a cavity will be of
enamel. In cavities present in the root of teeth,
which are exposed due to gingival recession, the
cavo-surface angle will be cementum. The enamel
margin includes the whole outline of the prepared
cavity.

59. • The Dentino-enamel junction:
Also called amelo-dental junction, is the line
of junction of dentin and enamel as it appears in
the walls of the prepared cavities.
• The Enamel wall:
It is that portion of a prepared cavity, which
consists of enamel. It includes the thickness of the
enamel from the dentino-enamel junction to the
cavo-surface angle.
• The Dentin wall:
It is that portion of the wall of a prepared
cavity, which consists of dentin.

60. The Dentino-Enamel JunctionThe Dentino-Enamel Junction
The Enamel WallThe Enamel Wall
The Dentin WallThe Dentin Wall

61. Thank You