Time Domain Optical Coherence Tomography Evaluation of Polymeric Fixed Partial Prostheses

Polymeric fixed partial prosthesis represents an important part of the prosthetic treatment. Their presence in the oral cavity could lead to fracture them and to alter the final prosthetic treatment. Time Domain Optical Coherence Tomography can be used as a noninvasive evaluation method and 3D reconstructions which could generate a real forecast on those prosthesis in the oral cavity environment. Keywords: polymeric fixed partial prosthesis, optical coherence tomography, non invasive method, material defect A fixed partial prosthesis should be well fabricated in order to maintain the health of the pulpal, periodontal and dental tissues from the time of tooth preparation until delivery of the definitive prosthesis [Gegauff and Holloway, 2001]. In order to achieve optimal tissue health the dental prosthesis must have good marginal fit, proper contour and smooth surfaces. The longer the period of time in which a dental prosthesis is in use the better fabricated it must be in order to ensure for proper tissue health [Shillinburg et al, 1997]. According to Rosenstiel [2001] the biologic category should include pulpal and tooth fracture protection, maintenance of periodontal health and tooth position and occlusal compatibility. Gingival health is very important in fixed partial prosthesis where the master impressions and cementation are to be completed. Imflamed gingival tissues can make these moisture sensitive procedures very difficult. As a result, many authors suggested the use of If any of these are not properly fabricated and maintained, inflammation and recession of the free gingival margin A polymeric fixed partial prosthesis should be well fabricated in order to withstand stresses produced during mastication and prevent displacement [Gegauff and Holloway, 2001, Gratton and Aquilino, 2004]. Multiple authors have studied the amount of stress and force a fixed prosthesis must withstand while in function. The average chewing functional load per tooth on a fixed prosthesis ranged 2 – 22 N with an increase in the load of 15 % during swallowing [Bates et al, 1976; DeBoever et al 1978, Neill et al, 1989]. However, other investigators found that this load had a higher range of 20 – 90 N [Anderson, 1956, Gibbs et al, 1981]. The chewing frequency in humans has been found to be about 1.25 to 2 Hz [Carlson 1974, Neill and Howard, 1988] with a definitive dental prosthesis required to undergo 3 x 10 6 to 10 7 load cycles in a 5 – 15 year lifetime depending on the author [Bates …