[Experimental study on microleakage between a new nano-hydroxyapatite composite and tooth]

Area of Science:

• Dental Materials Science
• Biomaterials Engineering
• Restorative Dentistry

Background:

• Dental restorations require materials with excellent marginal adaptation to prevent microleakage and secondary caries.
• Nano-hydroxyapatite composite resins are emerging as promising biomaterials due to their biocompatibility and mechanical properties.

Purpose of the Study:

• To evaluate the marginal adaptation and microleakage of a novel nano-hydroxyapatite composite resin against tooth structure.
• To compare the performance of the new nano-hydroxyapatite composite resin with conventional composite resin and glass ionomer cement.

Main Methods:

• Thirty extracted premolars were divided into three groups, using nano-hydroxyapatite composite resin, Karisma composite resin, or glass ionomer cement.
• Following thermal cycling, teeth were immersed in methylene blue dye to assess microleakage depth.
• Microleakage was quantified to evaluate the marginal integrity of each restorative material.

Main Results:

• The mean microleakage depths were 1.20±0.81 mm for nano-hydroxyapatite composite resin, 1.94±0.70 mm for Karisma composite resin, and 1.73±0.54 mm for glass ionomer cement.
• No statistically significant differences in microleakage depth were observed among the three groups (P>0.05).

Conclusions:

• The new nano-hydroxyapatite composite resin exhibits favorable marginal adaptation to tooth structure.
• This novel material demonstrates comparable performance to existing restorative materials regarding microleakage.