1. PRIMARY DENTITION ANATOMY AND CAVITY PREPARATION 2004-2005
D262 Division of Orthodontic & Paediatric Dentistry University of Western Ontario Dr. Sahza Hatibovic-Kofman
PRIMARY DENTITION ANATOMY AND CAVITY PREPARATION

2. GENERAL OBJECTIVES:
To present the anatomy of primary teeth and key anatomical differences between primary and permanent teeth that influence cavity preparation.

3. SPECIFIC OBJECTIVES: (1) Describe the general morphological
differences between primary and
permanent teeth and their clinical
implications.
(2) Identify special features and location of the
roots of primary teeth. Comment on
clinical applications.
(3) Describe the general morphology of the
dental pulp, location of the pulp horns and
orifices of canals in the primary teeth.
Comment on clinical considerations.

4. Specific Objectives (continued):
(4) Identify histological differences between
the pulp of primary and permanent teeth
and the clinical relevance.
(5) Identify the reason for most restorative
problems in paediatric dentistry.
(6) Describe the principles of operative
dentistry.
(7) Describe the steps for preparation and
restoration of Class I and Class II amalgam
restorations.

5. Specific Objectives (continued):
(8) Describe common errors in Class I and II
restorations.
(9) Describe the differences in cavity
preparation when composite is used as
a restorative material for primary teeth.

6. Most problems in paediatric dentistry occur because of
failure to prepare and restore the teeth in a way that takes into account their:
ANATOMIC or MORPHOLOGIC structural characteristics and limitations.

7. ANATOMIC CONSIDERATIONS OF PRIMARY TEETH
1. Crowns of primary teeth are smaller, and
more bulbous than permanent teeth.
2. Both lingual and buccal walls of the
primary teeth taper occlusally, therefore
the occlusal surface is quite narrow.
3. Primary teeth demonstrate greater cervical
constriction and have more prominent
cervical enamel contour than permanent
teeth.

9. Anatomic considerations (continued)
4. Primary teeth have thinner enamel and
dentin than permanent teeth.
5. The pulp of primary teeth are larger in
relation to the crown than permanent teeth.
The pulp horns of primary teeth are closer
to the outer surface of the tooth than for
permanent teeth.
The MESIOBUCCAL pulp horn is the most prominent.

12. Anatomic considerations (continued)
6. Fine canals.
7. Thin pulpal floor.
8. The roots of primary teeth are long, slender
and curved. Interradicular space can
accommodate the developing permanent
tooth.
9. In primary teeth the enamel rods of the
gingival third of the crown extend in an
occlusal direction. The rods of the
permanent teeth extend in a cervical
direction.

16. Anatomic considerations (continued)
10. Primary teeth have broad, flat proximal
contact areas.
11. Primary teeth are whiter in colour than
their permanent successors.

20. PRINCIPLES OF OPERATIVE DENTISTRY
Gain access.
Establish outline form
Eliminate caries.
Establish resistance and retention form.
Refinement and debridement of the cavity.

23. RESTORATIVE TRAY - SPEC
1. Mirror
2. Explorer
3. Cotton pliers
4. Small spoon
5. Large spoon
6. Hatchet
7. Small condensor
8. Large condensor

24. Restorative Tray (continued)
9. T-3 (Beaver tail)
10. Discoid-cleoid
11. Burnisher
12. G-38 (gold knife)
13. PFI (black felt)
14. Syringe

33. INFORMATION
In order to provide the best care for the child patient and teach excellence, we, at the children’s clinic, have decided to use tooth-coloured materials and stainless steel crowns as a first choice of treatments.
Occasionally other materials will be used according to the medical indications and/or child/guardian demand.

34. Montreal, November 27, 2000
It was very refreshing for us, as clinicians, to hear from a university professor that the University of Western Ontario actually teaches dental materials and techniques that are up-to-date, in order to prepare the students to the challenges of everyday clinical dental pediatric practice.
… J. Victor Legault
Quebec Assoc. of Pediatric Dentists

35. Information (continued)
Currently, there are four conventional and two hybrid restorative materials available for the restorations in primary teeth.
Conventional materials:
1. Stainless steel crowns (SSC).
2. Amalgam.
3. Composite resin.
4. Glass ionomer cement (GIC).

36. Information (continued)
Hybrids:
1. Resin-modified glass ionomer cement
(RMGIC).
2. Polyacid-modified resin composite
materials (PMRC), compomer.

37. Information (continued)
The restorative material for primary teeth should possess the following properties:
be biocompatible
join a strong adhesive bond to reminded tooth
strengthen residual tooth structure
easy handling characteristic
be economical

38. Information (continued)
Amalgam is good material and has been used successfully for about 200 years, but tooth coloured materials accompanied with the bonding systems offer advantages over dental amalgam in:
Preservation of healthy tooth structure. Today literally we can restore a tooth by removing only decayed structure. To accommodate amalgam a lot of healthy tooth structure has to be removed to provide mechanical retention of the restoration.

39. Information (continued)
Repairability.
Esthetics.
Release of fluoride.
Our students are performing high quality care for the child patient and will be using the most current tooth-coloured materials.

40. GUIDELINES for Usage of the Restorative Materials in Mixed Dentition
First step in restorative dentistry is to perform good caries diagnosis and elimination of the lesion.
Under diagnosis = misdiagnoses.
In the SPEC clinic after visual diagnosis, we will use regularly light caries detector “DIAGNOdent” and/or dye caries detector “Seek and Sable”.

46. STATE OF THE TOOTH
Caries free primary and permanent teeth
Small decalcification
Small lesion in dentin occlusally
TREATMENT
Pit and fissure sealants
Bur preparation or air abrasion - pit and fissure sealants
Cavity preparation, and use caries seek and restore it with composite

47. STATE OF THE TOOTH
MO or DO
DO or MO next to permanent tooth if exfoliation will occur within two years.
TREATMENT
Conservative preparation without extensions for prevention and use combination of flowable and filled composite.
Conservative cavity preparation and glass ionomer cement.

48. Guidelines (continued)
Multi surface lesions and teeth after pulp therapy will be restored with stainless steel crown (SSC).

49. STEPS FOR PREPARATION AND RESTORATION OF CLASS I AMALGAM RESTORATIONS
Administer appropriate anaesthesia and place the rubber dam.
Using a No. 330 bur gain access and penetrate into the tooth to a depth of 0.5 mm into dentin.
Removal all carious dentin by using large, round bur.
Provide retention and resistance by making cavity surface parallel with its external surface.

50. Steps Class I (continued)
Smooth the enamel walls and refine the final outline form with No. 330 bur.
Place pulp protection as needed.
Place and condense amalgam.
Carve amalgam.
Burnish the carved amalgam when it has begun its initial set and resists deformation.
Remove the rubber dam and check the occlusion.

54. COMMON ERRORS WITH CLASS I AMALGAM RESTORATIONS
Not including all susceptible fissures.
Preparing the cavity too deep.
Undercutting the marginal ridges.
Carving the anatomy of the amalgam too deep.
Not removing the amalgam flash from the cavosurface margins.
Undercarving, which leads to fracture of the amalgam from hyperocclusion.

55. STEPS FOR PREPARATION AND RESTORATION OF CLASS II AMALGAM RESTORATIONS
Administer appropriate anaesthesia and place the rubber dam.
Place a wooden wedge in the in interproximal area.
With No. 330 bur in the high speed turbine handpiece, prepare the occlusal outline form at the ideal depth.

56. Steps Class II (continued)
To prepare the proximal box, use the same bur moving it buccolingually in a pendulum motion and in a gingival direction. The contact should be broken between the adjacent tooth gingivally, buccally and lingually.
Remove any remaining caries.
Round axiopulpal line angle.
Remove any unsupported enamel off the buccal, lingual and gingival walls.

57. Steps Class II (continued)
Place pulp protection if necessary.
Remove the wedge, place a matrix band, and reinsert the wedge.
Condense amalgam.
Carving of the occlusal portion is performed with a small carver. The marginal ridge can be carved with the tip of the explorer.
Remove the wedge and the matrix.
Gently floss the interproximal contact.
Burnish the restoration.
Remove the rubber dam and check occlusion.

77. PROCEDURE OF CLASS II CAVITY PREPARATION FOR COMPOSITE RESTORATION
1. A local anaesthetic will be administered in the usual fashion and in the appropriate amount to ensure adequate anaesthesia during the procedures.
2. A rubber dam will be used routinely.
3. Wooden wedges will be inserted in the proximal areas to maximize the protection of gingiva and the adjacent tooth, and protection from tearing the rubber dam by bur.

78. Procedure Class II(continued)
4. The outline form of the cavity preparations
will be conservative as presented in the
picture.
5. No flaring buccal and lingual walls of the
proximal box.
6. Caries has to be completely removed,
please use seek and sable.
7. The line angles will be rounded slightly,
but the cavity will not be extended for
prevention.
8. Do not remove healthy and unsupported
enamel.

79. Procedure Class II(continued)
9. Rinse the cavity.
10. A “cure-thru” celluloid matrix band or
onmi-paedo matrix will be inserted firmly
into place.
11. Acid etch the cavity for 25 seconds.
12. Rinse it for 20 seconds.
13. Rub in one bottle bonding system, air dry
and cure for 10 seconds.
14. Apply flavable composite on the edges
cure it.

80. Procedure Class II(continued)
15. Restore with filled composite (do good
modeling to be able to avoid finishing).
16. Cure for 40 seconds.
17. The matrix band will be removed and the
restoration will be finished and polished.
Finishing and polishing will be done by
using finishing and polishing discs and
strips.
18. The rubber dam will be removed and the
occlusal contacts evaluated and adjusted
as necessary.

81. Procedure Class II(continued)
19. Any tooth with carious or iatrogenic pulp
involvement will obtain pulp treatment, and
stainless steel crown.

92. PREVENTIVE RESIN RESTORATION (PRR)
OBJECTIVES:
1. List the indications and contra-indications for PRR for primary and permanent teeth.
2. Describe the PRR materials.
3. Describe the clinical procedures for PRR.
4. Identify the advantages of using PRR and their cost effectiveness.

93. PRR (continued)
Non-surgical management of initial carious lesions by remineralizaiton offers an opportunity to extend preventive dentistry into early therapy.
It is now recommended, for smooth surface, that cavity preparation and restoration placement is appropriate only after the lesion has progressed into the dentin.

132. RUBBER DAM AND MATRIX APPLICATION 2004-2005
D262 Division of Orthodontic & Paediatric Dentistry University of Western Ontario Dr. Sahza Hatibovic-Kofman
RUBBER DAM AND MATRIX APPLICATION

133. GENERAL OBJECTIVES:
Discuss the armamentarium and application of the rubber dam
in paediatric patients.

134. SPECIFIC OBJECTIVES: (1) Identify the need, indications and relative
contraindications for the paediatric patient.
(2) State the advantages of rubber dam and
describe its preparation for a paediatric
patient.
(3) Describe clamps and their applications.
(4) Describe the explanation of the rubber dam
to the child.
(5) Select and apply the matrices for Class II
preparations in primary molars.

135. RELATIVE CONTRINDICATIONS:
All paediatric restorative procedures should be completed with the rubber dam in place.
RELATIVE CONTRINDICATIONS:
(1) Fixed orthodontic applicance.
(2) Partially erupted teeth.
(3) A child with upper respiratory infection.

136. ADVANTAGES: 1. Saves time. 2. Improvement of access.
3. Controls saliva.
4. Retraction and protection of soft tissues.
5. Prevention of the ingestion and inhalation
of foreign bodies.
6. Provision of aseptic environment.
7. Aid management.
8. Helps the dentist to educate parents.

162. Retrospective Clinical Study of Vitalescence in Primary Molars

163. Table 1: Clinical Performance of Vitalescence in Primary Molars A Three-Year Study

164. Table 2 - Success/Failure of Amalgam and Composite Restoration in SPEC Clinic and Private Practice - A Two-Year Study