Does the presence of an occlusal indicator product affect the contact forces between full dentitions

Summary Studies have explored occlusal marking interpretation, repeatability and accuracy. But, when an occlusion detection product is interposed between teeth, direct tooth-tooth occlusal contact relationships are replaced by tooth-material-tooth structures. Thus, the marks cannot reflect the original contacts. This has been shown for single tooth pair contacts. The purpose of this laboratory study was to similarly examine full dentitions. A dentiform was set into Class I centric occlusion with the mandible supported by a load cell. The maxillary arch was guided by precision slides. As the weighted (~52 N) upper assembly was lowered onto and raised off the mandibular arch, the loads on the mandible were measured. With and without (control) occlusal marking material, the steps were: (cleaning – control 1 – material 1) … (cleaning – control 6 – material 6). The 6 materials were: Accufilm I and II, Rudischhauser Thick and Thin, Hanel Articulating Silk, and T-Scan. Then, the 6 sets of (cleaning – control – material) measurements were repeated with the mandibular assembly shifted, in turn, by 0.1 mm in the Anterior, Posterior, Right and Left directions. The 5 (Centric and four 0.1 mm shifted) occlusal relationships produced grossly different tooth-tooth (control) load profiles. And, in general, these controls were affected, in different ways, by the marking products. Among the 5 conventional products, the Rudischhausers fared the worst and the electronic T-Scan was an extreme outlier. Thus, in general, popular occlusal detection products alter the occlusal contact forces, and therefore, their markings cannot characterize the actual occlusion. This article is protected by copyright. All rights reserved.