Microleakage of Class V composites using different placement and curing techniques: an in vitro study

Area of Science:

• Restorative Dentistry
• Dental Materials Science

Background:

• Microleakage remains a significant challenge in composite resin restorations, potentially leading to secondary caries and pulpal inflammation.
• Optimizing placement and curing techniques is crucial for minimizing marginal integrity.

Purpose of the Study:

• To compare microleakage in Class V composite restorations using two different composite resins (Z250 and Silux Plus).
• To evaluate the impact of bulk versus incremental placement techniques on microleakage.
• To assess the effect of "rebonding" and facial/lingual curing methods on marginal seal.

Main Methods:

• 100 Class V cavities in human premolars were restored using Z250 or Silux Plus composite resins.
• Five techniques were tested: incremental/bulk placement with facial/lingual curing and "rebonding" variations.
• Single Bond adhesive was used. Specimens underwent thermocycling, methylene blue staining, and sectioning for leakage evaluation (0-4 scale).

Main Results:

• Enamel margins exhibited negligible microleakage across all groups.
• Cementum margins showed significantly greater microleakage compared to enamel margins.
• No statistically significant differences in cementum microleakage were observed between the restorative materials or placement techniques evaluated.

Conclusions:

• Enamel margins provide a superior seal compared to cementum margins in Class V composite restorations.
• Current placement and curing techniques, including "rebonding," do not significantly alter microleakage at cementum margins.
• Further research is needed to improve the marginal seal of composite restorations at cementum interfaces.