Class III composite restoration, especially in cases of strictly proximal access, presents unique challenges. Small lesions in these areas are often hard to assess and treat without unnecessary damage to the surrounding tooth structure. This guide outlines a minimally invasive approach, focusing on tooth separation, cavity preparation, adhesive procedures, and finishing techniques for optimal results.

1.Strictly Proximal Access in Class III Lesions

Class III lesions can be difficult to detect and access due to their proximal location. Using small burs ensures the conservation of sound tooth structure while removing caries.

Key Challenges:

• Assessing lesion extent.
• Preventing unnecessary wear on healthy enamel.

2. Tooth Separation: Creating Space for Observation and Restoration

Tooth separation is a valuable technique for strictly proximal Class III lesions. By placing rubber rings or strips between the teeth 24-48 hours before the procedure, the teeth are gently separated.

Benefits of Tooth Separation:

• Better visualization of the lesion.
• Easier access for cavity preparation.

Pro Tip: Stabilize the separation using wooden wedges after cleaning the surfaces with a prophylactic paste and rubber cup.

3. Shade Selection: Matching Composite to Tooth Color

Shade selection is a critical step. Due to the small size of the lesion, typically only one composite shade is needed.

Tips for Accurate Shade Selection:

• Compare the tooth with a shade guide under natural light.
• Apply a small composite pellet to test its match.
• Ensure proper curing time as it impacts resin color.

4. Cavity Preparation: Prioritizing Conservation

Before adhesive procedures, the cavity surface must be cleaned using sodium bicarbonate or prophylactic paste.

Preparation Steps:

1. Insert a metal matrix to protect adjacent teeth.
2. Use small-diameter spherical burs for conservative cavity preparation.
3. Clean the cavity thoroughly before etching.

5. Adhesive Procedures: Ensuring Strong Bonding

The adhesive system plays a vital role in restoration longevity.

Steps for Successful Bonding:

• Protect adjacent teeth with Mylar strips or PTFE tape.
• Apply phosphoric acid for 15 seconds, extending 2 mm beyond cavity margins.
• Use a primer-adhesive combo and apply at least twice before light curing.

6. Composite Placement and Contouring

Apply composite resin in increments using appropriate spatulas. Use brushes to shape the material and remove excess for a precise contour. Finish with light curing to set the restoration.

7. Finishing and Polishing: Restoring Aesthetics and Function

Finishing flexible discs help smooth the surface, especially in proximal areas.

Final Steps:

• Remove wedges and rubber dam isolation.
• Allow teeth to return to their original position for restored proximal contact.

Why Choose This Protocol?

This conservative approach minimizes enamel removal and ensures a natural restoration. While it requires an additional appointment for tooth separation, the results justify the effort, providing excellent esthetics, function, and patient satisfaction.

Mastering strictly proximal access in Class III composite restoration requires meticulous planning and execution. By following this step-by-step guide, dental professionals can achieve optimal outcomes while preserving tooth structure.