Evaluation of the marginal adaptation of a fibreglass reinforced resin crown using a scanning electronic microscope

Introduction and objective: Dental prostheses manufactured usingreinforced resins are an alternative to the rehabilitative treatmentof one or more dental elements. With the aim of forecasting thelongevity of these prosthetic pieces, this study evaluated the marginal adaptation of a complete crown made from fibreglass reinforced resin.Material and methods: A tooth having orthodontic indication for extraction was prepared and a prosthetic piece was cemented over it so that, 48 hours later, the extraction could take place. The ensemble was taken in a laboratory and was examined using a scanning electron microscope (SEM). There were made 30 readings in a 8mm tooth-cement-restoration interface and revealed various gaps throughout the sample. Results: The lowest value found was 15,82 μm and the highest was 72,81 μm showing an average value of 40,82 μm. Conclusion: The gaps were within the limits of clinical tolerance and considering the clinical difficulty in making the prosthetic piece, the treatment was shown to be satisfactory with regard to marginal adaptation.