Operative Lecture 6: Anterior Restorations

What is the common cause of Class III restorations?

Interproximal caries at contact

Where should you approach Class III restorations?

Lingually

What are the two common causes of Class IV restorations?

1. Extension of Class III

2. Traumatic fracture

What are the two challenges of Class IV restorations?

1. Restoring translucency

2. Proper contour

What are the four common causes of Class V restorations?

1. Cervical caries

2. Abrasion

3. Erosion

4. Abfraction

What are the two challenges of Class V restorations?

1. Moisture control

2. Margin placement on gingival tissues

What are the four critical factors influencing anterior cavity design?

1. Enamel thickness

2. Esthetics

3. Pulp proximity

4. Adhesive principles

How thick is anterior enamel at the thickest point?

1 - 2.5mm

Do young patients have larger or smaller pulp/pulp horns?

Larger

Why are enamel margins the ideal bonding substrate?

97% inorganic

What pattern does acid etching create on enamel?

Microretentive

Does enamel or dentin have potential for post-operative sensitivity?

Dentin

What is the angled finish line that increases the surface area for bonding?

Bevel

What are the three clinical benefits of beveling?

1. Esthetic enhancement

2. Improved bonding

3. Stress distribution

What are the five situations when beveling is appropriate?

1. Enamel margins

2. Facial surfaces

3. Class IV

4. Existing composite

5. Stress distribution

What are the four situations when beveling is NOT appropriate?

1. Dentin/cementum margins

2. Subgingival margins

3. Thin enamel

4. Glass ionomers

What is the gold standard for isolating teeth for bonding?

Rubber dams

What is the alternative approach for isolating teeth for bonding if rubber dams are not available?

Cotton rolls + retraction

What is the isolation method critical for Class V preparations?

Retraction cord

What do Class III lesions begin as?

White spot lesions at contact point

What are the three visual indications of Class III lesions?

1. Shadowing

2. Chalky appearance

3. Cavitation

What are the three tactile examination techniques for Class III lesions?

1. Floss catching

2. Explorer sticking

3. Soft dentin

What are the three radiographic assessments for Class III lesions?

1. Bitewing

2. Depth assessment

3. Adjacent teeth

Why is it important to cure before evaluating color/shade?

Curing may change color of composite

Why would lingual accesses be preferred?

Esthetics

Why would facial accesses be preferred?

Defects on facial surface

Is it recommended to make both a facial and lingual opening (Donut Prep)?

No

Where should you point the bur during Class III restorations?

Center of decay

Should you point the bur directly at the contact area during Class III restorations?

No

What angle should you follow during Class III restorations if the tooth is maxillary?

Incisally

What angle should you follow during Class III restorations if the tooth is mandibular?

Gingivally

Once inside the dentin, what should the bur be parallel to in Class III restorations?

Long axis of tooth

What should you focus on preserving in restorations?

Facial enamel

What should you avoid removing in restorations?

Unsupported enamel

What is the adequate depth of the axial wall in dentin?

0.2 - 0.5mm

Which two angles should be rounded to minimize stress during restorations?

1. Axiogingival

2. Axioincisal

What is the main retention in restorations?

Bonding

How should internal walls interact with the axial wall?

Slightly converge

Should there be sharp internal walls in restorations?

No

When should small grooves and roughening be used in restorations?

Enamel is minimal

What are the three things discolored teeth usually indicate?

1. Demineralization

2. Microcracks

3. Underlying caries

What are the two prevention methods of inadequate caries removal?

1. Caries detector dyes

2. Excavate until dentin is firm

What is the prevention method of overextension of facial margin?

Conservative lingual access

What is the prevention method of sharp internal line angles?

1. Round angles with round bur

2. Smooth internal flow

What is the prevention method of beveling dentin margins?

Use butt joint for cementum/dentin margins

What are the five benefits of using matrix bands in restorations?

1. Protect adjacent tooth

2. Proper contouring

3. Prevent overhang

4. Eliminate air voids

5. Smooth surface

Why must wedges be used when placing matrix bands?

1. Stabilize band in place

2. Slight tooth separation

What are the four ideal requirements of matrix band material?

1. Thin, tight contact

2. Smooth

3. Flexible, but rigid

4. Clear

What thickness should composite increments not exceed?

2 mm

What is the shaping, contouring, and smoothing of the restoration called?

Finishing

What are the shine or luster of the restoration surface called?

Polishing

Which restoration class is the greatest challenge in anterior esthetics?

Class IV

What does the outline form for Class IV preparations depend on? (2)

1. Extent of defect

2. Proximal contacts

Which class of restorations has the minimal means of retention?

Class IV

What does Class IV restorations solely depend on?

Adhesion

What is the issue for larger restorations in Class IV?

More displacing forces

Should facial bevels for Class IV restorations be long or short?

Long

Should lingual bevels for Class IV restorations be long or short?

Short (Conservative)

What are the four critical functions of long facial bevels in Class IV restorations?

1. Esthetic blending

2. Increased bond area

3. Stress distribution

4. Margin camouflage

What are the four critical functions of short lingual bevels in Class IV restorations?

1. Less critical esthetically

2. Preserve tooth structure

3. Functional surface

4. Adequate bonding

What is the most common matrix system for Class IV restorations?

Mylar strip

What is the advantage of using mylar strips?

Smooth

What is the advantage of using sectional matrices?

Tight contacts

What are crown form matrices used for?

Traumatic fractures

What is the three advantage of using transparent wedges?

1. Improved gingival seal

2. Enables curing from gingival aspect

3. Reduces excess

What are the five characteristics of an ideal contact?

1. Junction of incisal/middle

2. Broad

3. Tight

4. Proper embrasure shape

5. Contour

What are the three hallmarks for restoring incisal translucency?

1. Layering strategy

2. Shade selection

3. Transition zone

Which location of Class V lesions is simplest to restore?

Supragingival

Which location of Class V lesions is most difficult to restore?

Subgingival

What are the two methods of restoring equigingival margin lesions?

1. Retraction cord

2. Glass ionomers

What are the two methods of restoring subgingival margin lesions?

1. Crown lengthening

2. Sandwich technique

What is the gold standard for moisture control in Class V restorations?

Rubber dams

What is critical for moisture control in subgingival restorations?

Gingival retraction cord

What are the four benefits of gingival retraction cords?

1. Controls bleeding

2. Dry field

3. Visibility

4. Protects tissues

What are the four alternative moisture control methods when rubber dams and retraction cords are not available in Class V restorations?

1. Cotton rolls

2. Dry angles

3. High volume evacuation

4. Optragate

When should you use bevels in Class V preparations?

Occlusal and lateral margins

When should you NOT use bevels in Class V preparations?

Gingival margin on root surface