Analysis of occlusal contact and guidance pattern during maximal intercuspal position and protrusive movement / 대한치과보철학회지

PURPOSE: The importance of occlusal contacts of the natural dentition for durability of teeth, mandibular stabilization, and restorative dentistry is well known. The purpose of this study is to analyze the occlusal contact and guidance pattern of Koreans by evaluating the static occlusion on maximal intercuspal position and measuring dynamic occlusion during straight protrusion. MATERIALS AND METHODS: The occlusal contacts at maximal interincisal position and the occlusal guidance pattern during straight protrusion of 29 subjects were recorded with shimstock foil (Whaledent, Langenau, Germany), T-Scan III (Tekscan Inc., Boston, MA, USA), polyvinylsiloxane registration material (Genie Bite, Sultan Healthcare, Hackensack, NJ, USA) and compared. Occlusal registration procedures were repeated 3 times. The position was fixed to an upright position and the head position was fixed with the Frankfurt horizontal plane paralleling the horizontal plane. Fisher's Exact Test (R-General Public License, ver. 2.14.1) and Pearson's Test were used to assess the significance level of the differences between the experimental groups (alpha=.05). RESULTS: When using shimstock foil, T-Scan III system, and polyvinylsiloxane registration material, most of the patients showed contact on anterior, premolar, and molar teeth during maximal intercuspal position. Approximately 51% of maximal intercuspal position showed anterior contact using shimstock foil. When examining the protrusive movement using shimstock foil and T-Scan III system, guidance pattern with the central incisor was the most common. CONCLUSION: During maximal intercuspal position, there were cases in which not all of the teeth showed occlusal contact. During mandibular protrusive movements, one or more maxillary central incisors frequently joined in straight protrusion and the posterior teeth were disoccluded. Therefore, the anterior teeth protect the posterior teeth, and vice versa. Thus, mutually protected occlusion should be applied when reconstructing occlusion.

Oclusión dental: ¿doctrina mecanicista o lógica morfofisiológica? / Dental occlusion: mechanistic doctrine or morphophysiological logical?

Las escuelas de oclusión han creado un constructo mecanicista que busca explicar, bajo un modelo reduccionista y determinista, una dinámica cráneo-cervical y estomatognática compleja. Estos modelos de oclusión le dedican más importancia a la morfología dental y sus geometrías interpretativas que a la morfofisiología estomatognática. La configuración musculo-esquelética cráneo-cervical tiene el poder ganado de influir concomitantemente en la ubicación espacial de la mandíbula e implícitamente en las relaciones interoclusales. La visión actual de la oclusión sigue basándose en observaciones empíricas de un siglo de antigüedad que carecen de soporte apropiado en el marco del nivel de evidencia. En la dimensión funcional los modelos de oclusión conservan los mismos vacíos que existían desde su estructuración en el siglo pasado, particularmente en sus representaciones espaciales estáticas, uniáxicas y anti-dinámicas que desestiman la individualidad de cada sujeto. Cada especialidad puede tener tantas razones como puntos de vista diferentes de "maloclusión" así como formas de tratarla.

Occlusion schools have created a mechanistic construct that seeks to explain, under a reductionist and deterministic model, a craneal-cervical and stomatognathic complex dynamic. These occlusion models dedicate more importance to dental morphology and its interpretative geometries than a stomatognathic morphophysiology. Craneocervical musculoskeletal configuration has the gained power to concomitantly influence the jaw location in the space and implicitly in the interocclusal relations. The current vision of the occlusion is based on empirical observations of almost a century that lack support in the level of evidence framework. In the functional dimension occlusion models maintain the same gaps that existed from its origins since the last century, particularly in its static, uniaxic and anti-dynamic spatial representations that dismiss the individuality of each subject. Each specialty can have as many reasons as different points of view about "malocclusion" as well as techniques to treat it.