Introduction: Resin infiltration technique is a promising option for treatment of incipient enamel lesions, especially for patients with history of fixed orthodontic appliances. However, its ability to resist aging under thermal influences in the oral cavity is still questionable. Aim of the study: The present research aimed to inspect the ability of resin-infiltrated initial enamel lesions, to resist aging under thermal challenge.
Materials and methods: Fifty extracted non-carious premolars were included in the present study. Specimens were equally distributed into 5 groups, where group 1 included teeth with sound enamel (control), while group 2 included teeth with decalcified untreated lesions. Specimens of group 3 were subjected to Icon® resin infiltration after decalcification. For groups 4 and 5, decalcified resin-infiltrated specimens were subjected to thermocycling (TC) at 5,000 or 10,000 cycles respectively. Surface evaluation parameters included surface microhardness and roughness. Surface morphology was further evaluated using scanning electron microscope (SEM). For statistical analysis, ANOVA and LSD tests were used.
Results: Resin-infiltrated enamel was more resistant to surface changes, under thermal stresses, than the non-resin-infiltrated enamel. The resin surface showed high resistance to surface degradation at thermal stress of 5000 cycles, while more deterioration started to appear at 10,000 cycles.
Conclusion: Resin infiltration has the ability to provide adequate protection to the demineralized enamel against thermal attack of 5,000 thermal cycles. However, surface microcracks generated at 10,000 thermal cycles indicate that the material might further deteriorate on aging for more than one clinical service year.