Volume fraction and location of voids and gaps in ultraconservative restorations by x-ray computed microtomography
735 Words3 Pages
Caries diagnosis in contemporary operative dentistry focuses on the earliest detection of carious lesions in order to prevent a progression to a more severe stage or in case that an operative intervention is needed, to remove minimal only amount of tooth substance1,2. Unfortunately, the decision for an operative intervention is not an easy task3 and is becoming even more complicated when decision includes the appropriate restorative technique.4 Decisional problems on restorative treatment of such early lesions is related to the technology available for removing selectively a very small part of tooth substance, and of course to the clinical technique for inserting a restorative material in the prepared cavity, in complete and intimate contact with all its walls.
Adaptation of the filling material on cavity walls is affected by material, cavity and operator factors. Bond strength and polymerization shrinkage of a material are directly related to its adaptation to cavity walls5-7 through its flow, modulus of elasticity and wettability7,8. Cavity factors important to adaptation are the number of walls, access to these walls and wall quality9,10, while type of material, material handling and method of insertion are the operator factors11-13. If the negative effects of these factors on material adaptation are not properly identified and handled, a gap of variable size will be formed between cavity walls and filling material, immediately after or a little later following its polymerization.
Gap formation between cavity wall and restorative material was always the center of researcher’s interest, because of its significance to microleakage, post-operative sensitivity and secondary caries formation14-16. Light, scanning elec...
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...een given to the preparation technique in order to facilitate measurements. For these reasons, a method that could permit the investigation of gaps in a more clinically relevant setting of the entire cavity preparation, and in dimensions closer to an ultraconservative cavity would be of significant importance to the study of gap formation and location in such cavities.
The purpose of this study was to validate a procedure designed to compare differences in densities between several different in dimensions ultraconservative cavities and to test the hypotheses that the materials used for direct restoration of ultra-conservative cavities present no differences in the amount of internal voids or at the material-wall interface, that cavity dimensions are not associated with voids and gaps and that location of voids is not associated with a specific restorative material.