Authors: Monica Mihaela IACOV-CRĂIŢOIU, Sanda Mihaela POPESCU, Marina AMĂRĂSCU, Monica SCRIECIU, Eugen OSIAC, Veronica MERCUŢ


Fixed partial bridges represent the most used therapeutic method in oral rehabilitation in Romania. Survival rate of dental bridges is almost 90% after 10 years. Most failures of dental bridges are biological in nature, caused by a defective marginal fit of the dental crowns. The aim of the study is to establish the failure rate of dental crowns (components of dental bridges) and to show OCT application in evaluating their marginal fit. Materials and methods. Panoramic radiographs taken from 22 patients with fixed dental bridges underwent a marginal fit evaluation. 10 teeth covered with different types of crowns, extracted as a consequence of periodontal breakdown, were selected from 85 extracted teeth. Teeth were washed under running water, scaled to remove periodontal tissue and calculus, and then OCT scanned. For the experiment, we used an OCT system manufactured by Thorlabs (OCS1300SS) powered by a swept laser source with central wavelength of 1310 nm, a spectral bandwidth of 100 nm, and an average power of 12 mW. Results and discussion. Out of the 154 teeth covered with crowns, 6.493% showed poor marginal fit, especially the second molars. OCT examination showed multiple sectorial deficiencies in the cervical marginal fit of crowns, especially on second molars distal surfaces, a clinically and radiologically undetectable situation.Conclusions. OCT in dentistry was used for both hard and soft tissues, oral mucosa and periodontal tissues. Poor cervical marginal fit of the fixed prosthetic restorations is the most common cause of dental bridges’ biologic failure

  • dental bridges
  • marginal fit.
  • Optical Coherence Tomography