IADR/AADR/CADR location:San Diego date:6-9 march 2002
Conventional methods of TEM microscopy are time consuming, especially when demineralized and non-demineralized specimens are evaluated separately. Objective: Evaluate a new TEM specimen preparation technique to simultaneously study demineralized and non-demineralized regions of resin dentin interfaces within the same section. Methods: Six extracted human third molars stored in 0.5% Chloramine at 4°C were used within one month of extraction. Mid-coronal dentin was obtained by sectioning the crown 4-5 mm above the cementum-enamel junction using a low-speed diamond saw. A total-etch three-step adhesive (Optibond FL, Kerr) was used to bond resin composite to dentin. Multiple sections perpendicular to the resin-dentin interface were made to obtain six rectangular sections of 1x1x4 mm. At random the sections were distributed to 3 groups: demineralized specimens (control), non-demineralized specimens (control) and partially demineralized specimens (novel approach). All specimens were then processed according to conventional electron microscopy methods. Results: There were no differences in ultramorphological characteristics between the control or conventional method and the novel approach. Conclusion: This novel approach, partial demineralization of resin dentin interfaces, is an efficient and appropriate method for ultrastructural evaluaiton of the resin-dentin interfaces.