Adverse Reaction Reports Related to Occlusal Splints

Objectives: The Norwegian Dental Biomaterials Adverse Reaction Unit is responsible for a national register concerning suspected clinical biologic adverse reactions associated with dental biomaterials. The register is based on voluntary reporting from dentists, dental hygienists and physicians. The main objectives of the adverse reaction register are to gain knowledge about material-associated adverse reactions and to monitor changes over time. In this study we focused on reactions reported in relation to occlusal splints. Occlusal splints are made of polymer materials (e.g., auto-polymerized, heat cured, thermoplastic, light cured, or 3D-printed). For some of these the biocompatibility is not well characterized.
Methods: A customized reporting form is available from the Norwegian Dental Journal, from the internet pages of the Norwegian Dental Biomaterials Adverse Reaction Unit, and from the most used electronic patient record software in Norway. Data from received adverse reaction reports were registered in a database and reports regarding reactions related to occlusal splints were searched for. The number of reports where the reporter suspected occlusal splints as a possible cause of the reaction was counted for each year.
Results: From 1993 to the end of 2022, 20 out of a total of 2725 reports registered were related to occlusal splints. Six of these reports were received the last two years. Analysis using logistic regression indicated a significant increase over time (p=0.002).
The symptoms reported were relatively consistent and included mainly burning and painful sensations in the orofacial region. The objective findings were less consistent.
For most splints there was no detailed information about the manufacturing process used.
Conclusions: The increase of adverse reaction reports related to occlusal splints could be interpreted as a signal and the mechanism behind the experienced adverse reactions warrants additional investigation.