Fragment reattachment or direct restoration? An in vitro study

Area of Science:

• Dental Materials Science
• Restorative Dentistry
• Biomaterials Engineering

Background:

• Tooth fractures requiring restoration are common.
• Fragment reattachment is a conservative treatment option.
• Intermediate bonding materials may enhance fracture resistance in reattachment procedures.

Purpose of the Study:

• To evaluate the fracture resistance of teeth restored with fragment reattachment using various intermediate materials.
• To compare the efficacy of pre-heated composite resin against other bonding agents and direct composite restorations.

Main Methods:

• Simulated tooth fractures were repaired using different intermediate materials, including pre-heated composite resins (Z100, Filtek Z350 XT) and conventional materials (Z100, Filtek Z350 XT Flow, RelyX Veneer).
• A control group of sound teeth and a group with direct class IV restorations were included.
• Fracture resistance was measured using a universal testing machine under compressive load.
• Statistical analysis included one-way ANOVA and Tukey's post hoc test.

Main Results:

• Sound teeth (G0) exhibited the highest fracture resistance.
• Pre-heated resins (G2, G4) showed fracture resistance statistically similar to sound teeth.
• Significant differences were noted between some conventional and pre-heated groups (G1 vs. G2).
• No significant difference in fracture resistance was found between fragment reattachment and direct composite resin restorations.

Conclusions:

• Pre-heated composite resin for tooth fragment reattachment provides fracture resistance comparable to sound natural teeth.
• The fragment reattachment technique, particularly with pre-heated resin, is as effective as direct composite restorations in terms of fracture resistance.
• This study supports the use of pre-heated composite resins as a viable option for improving outcomes in tooth fragment reattachment.