Restorative & aesthetic in pediatric dentistry l Pediatric dentistry & dentistry for children MCQs

Restorative & aesthetic in pediatric dentistry  l Pediatric dentistry & dentistry for children MCQs for dental students 

 

Restoration used in pediatric dentistry for children teeth :

• Amalgam

• Composite

• Silver diamine fluoride (SDF)

• compomer. 

• Glass Ionomer cement .

 

Tooth crown used in pediatric dentistry for children teeth :

• Polycarbonate crown

• Stainless Steel crown

• Celluloid strip crowns

 

 

 

Modification of cavity preparation in primary teeth

• The principle of conventional cavity preparation apply to primary teeth with some modifications in order to take into consideration the morphological and histological differences between the primary and permanent teeth. The following characteristic of primary teeth should be considered while making the cavity preparation in a primary teeth:

1. Thinner enamel and dentin.
2. Smaller, more bulbous crown and narrow occlusal table.
3. Proximity of pulp chamber to the outer surfaces and high pulpal horns.
4. Broad contact area.
5. Prominent faciogingival ridge.
6. Pronounced cervical constriction.
7. Occlusal orientation of enamel rods in the cervical area.

 

The modification for class I cavities

1. Shallow depth of the cavity. The depth of the cavity in primary teeth should be not more than 0.5 mm in the dentin.
2. Width of the cavity buccolingually is kept less due to the narrow occlusal table.
3. The pulpal floor should be kept either flat or slightly concave to protect underlying pulpal horns.
4. Rounded line and point angle.

 

In Class II cavities

1. More clearance from the adjacent tooth due to wider broad contact areas. Buccolingual extension of the proximal box should be more for the similar reasons.
2. Convergence of the proximal box occlusally and divergence of the proximal box cerivcally .This is done due to broad proximal contact.
3. Isthmus width is kept at 1/ 3rd the intercuspal distance.
4. The axiopulpal line angle should be beveled or grooved to reduce the stresses.
5. Width of the gingival floor should be kept at minimum.
6. As in the cervical area the enamel rods are oriented occlusally there is no need to bevel the gingival floor in case of primary teeth.

 

Kinetic cavity preparation (Air abrasion):

• Uses kinetic energy to remove the tooth structure. The procedure is painless and without any discomfort to the patient.The KCP produces less vibration and heat. KCP can often be used without anesthetics. The technique uses microscopically fine powder of aluminum oxide, carried to the tooth by a compressed stream of air, gently spraying away decay. These aluminum oxide crystals are between 25 and 50 microns in size and are injected around the tooth under compressed air of anywhere from 100 to 80 psi. In most cases, no local anesthesia or needles are even needed for the treatment.

 

Matrices used for restoration

• For compound class I cavity (Buccal—lingual complex) for amalgam—Double banded toffelmire
• Matrices used for class II cavity for amalgam-Single bonded Toffelmire, Ivory matrix No I and 8,8- shaped matrix,T-shaped matrix, Automatrix
• For class V amalgm—Shaped matrix or window matrix is used.
• Matrices for class III and IV-Celluloid strips, Aluminum foil, celluloid crown form, Anatomic matrix.
• For Class V tooth colored restorations—Celluloid strips, aluminum or copper collars.
• Matrix for Class I and class II cavities for composite restoration—Sectional matrix with G—rings

 Dental amalgam: 

•  is a mixture of Ag-Sn alloy (with varying amount of Cu and Zn) and mercury .The plastic mass which results from the mixture of alloy and mercury after propionate dispension is carried into the prepared cavity and is pressed and condensed in increment into the prepared cavity against its wall and floor.

 

Indication of dental amalgam restoration in primary teeth: 

• dental amalgam is indicated for class I and class II lesion of primary molar. The material is a better choice Where the children are not cooperative and method of isolation or moisture control are not adequate for highly technique sensitive GIC or composite restoration. Zinc free high copper alloy are preferred where moisture control is difficult.

 
The cavity design for amalgam restorations

1. The extension of the cavity preparation should include any caries-susceptible pits and fissures.
2. Cavosurface margin of 90 degree.
3. Depth into the dentin of 0.2 to 0.5 mm.
4. Flat or slightly concave pulpal floor.
5. Slightly rounded or beveled isthmus .The amalgam material should have an adequate strength at isthmus. This is the most vulnerable area from where the amalgam restoration fracture.
6. Isthmus width of 14 of the intercuspal distance.
7. Adequate clearance from the adjacent tooth.
8. The angle formed by the axial wall and the buccal and lingual walls of the proximal box should approach a right angle.
9. The buccal and lingual walls should diverge toward the cervical region following the general contour of the tooth.

 

Glass Ionomer cement :

• Is based on the reaction between fluoroalimunosilicate glass cement and polyacrylic acid. The material is biologically kind, has the potential to adhere chemically to the tooth substance and also has ability to release fluoride. Due to all these properties, glass ionomer cement is used Widely as restorative material in primary teeth. Other application of this material is as a luting cement and as a liner and base.

1. Type I GIC is used for luting purpose
2. Type II is used as restorative material
3. Type III is used as liner/ base

 

Resin modified Glass inomer :

• cement or hybrid glass ionomers or light-cured glass Ionomer is the resin reinforced glass ionomer cement. This cement overcome the drawback of conventional GIC which include short working time, slow development of ultimate properties, sensitivity to both moisture exposure and dehydration during setting, and lower cohesive strength

 

Composite resins :

• Are tooth colored synthetic resin that generally consist of an organic resin matrix, reinforcing inorganic filler and a silane—coupling agent, which connects the filler and the resin matrix.The resin matrix consist of bisphenol A-glycidyldimethacrylate (bis-GMA) or urethane dimethacrylate resin. In addition to bis GMA, composite resins generally include other monomers to modify the properties of the resin, for example bisphenol A dimethacrylate (bis—DMA), ethylene glycol dimethacrylate (EGDMA) and triethylene glycol dimethacrylate (TEGDMA). The filler consist of ground particles of fused silica, crystalline quartz, and soft glasses such as barium, strontium, and zirconium silicate glass.

Compomer:

• are a hybrid of two other dental materials: dental composites and glass ionomer cement. They are also known as polyacid-modified resin composites.

Miracle:

• mix is a metal (Silver alloy) reinforced glass ionomer.

 

Silver diamine fluoride (SDF):

• SDF is liquid with antibacterial effect .
• silver : for antibmicrobial effect .
• Fluoride: allow remineralization and the ammonial stabilizes high concentrations in solution.
• In August 2014, the Food and Drug Administration (FDA) cleared the first silver diamine fluoride product for use.

Indication of Silver diamine fluoride (SDF):

1. immediate relief from dentinal hypersensitivity.
2. Antimicrobial effect (Kills pathogenic organisms).
3. Hardening the dentin which become soft → more resistance acid and abrasion.
4. no staining sound dentin or enamel.
5. provide important clinical feedback due to staining visible cavities or hidden cavities black permanently

Advantage for using SDF:

1. Severe early childhood caries which is difficult to treat due to young age patient’s
2. Treatment can be accomplished by behavioral or medical management.
3. Large cavity can’t be treated in one visit.
4. Alternative to doing restorations.
5. Re-application is usually recommended, biannually until the cavity is restored or arrested or the tooth exfoliates.
6. A control restoration may be considered after Silver Diamine Fluoride  treatment.

Contraindication for the use of SDF:

1. Allergic to silver or fluoride.
2. painful sores or raw areas on gums (i.e. ulcerative gingivitis or stomatitis).

 

 

Tooth crowns used in pediatric dentistry :

 

Celluloid strip crowns:

•  are prefabricated transparent plastic crown forms used for restoring primary anterior and posterior teeth. Advancements in composite materials have made Strip Crowns more durable while reaming the most esthetic restoration for primary teeth. Strip Crowns are effective, quick and simple mean of restoration of primary incisors.

 

Stainless Steel crown :

• A preformed steel crown used for the restoration of badly broken-down primary teeth and first permanent molars. The chief goal of full coronal restoration using preformed stainless steel crowns (SSC) is replication of normal crown form and function. Marginal adaptation of SSCs involves appropriate crown size selection, trimming the crown form to achieve proper length, crimping crown edges to proximate the prepared tooth, and finishing and polishing the crown form

 

Polycarbonate crown:

• are semi-permanent full crown restoration made of polycarbonate material and are indicated for primary and permanent teeth in children. Polycarbonate crown are indicated for permanent teeth till the time ceramic crown restoration can be planned. In children ceramic full crown restoration for permanent teeth are indicated after the tooth complete its clinical crown length in the oral cavity.