The role of occlusal factor in the etiology of temporomandibular dysfunction

Abstract

Introduction. The influence of occlusal condition at the onset of temporomandibular disorders (TMD) has been strongly debated for many years and still is the source of controversy. Up to the eighties in the last century, the occlusal factors such as the presence of uncured malocclusions, discrepancies between intercuspal position and retruded contact position greater than two millimeters, retrusive and nonworking side interferences and loss of posterior teeth were considered to be the primary causes of TMD. Objective. The aim of this study was to estimate the role of occlusal factor in the etiology of craniomandibular dysfunction and therapeutic effects of irreversible occlusal therapy (occlusal equilibration) in patients with TMD. Methods. In the investigation we studied a group of 200 men and women. The average age of the selected patients was between18 and 25 years. The purpose of TMD signs and symptoms was confirmed in every patient using a special functional analysis and evaluating the craniomandibular index (CMI) according to Fricton and Schiffman. The value of craniomandibular index was determined in the group of 15 patients with signs and symptoms of temporomandibular dysfunction. In the study groups occlusal equilibration (selective grinding) was performed according to Okeson using the central position of the mandible as the referent position in the occlusal therapy. The value of CMI was determined before and 30 days after occlusal equilibration. Results. The results of this study confirmed the significant reduction in the signs and symptoms of TMD after occlusal equilibration. The statistical elaboration of the differences between the values of CMI I (before treatment) and CMI II (30 days after treatment) revealed highly significant differences. The CMI I values in the group ranged between 0.076 and 0.346 with the mean value of 0.188±0.082.The values of CMI II ranged between 0.038 and 0.19 with the mean value of 0.038±0.053. Conclusion. The study conformed the validity of irreversible occlusal therapy (selective grinding) in patients with TMD.

Uvod. Uloga okluzivnih disharmonija u nastanku temporo-mandibularnih disfunkcija (TMD) i dalje je pitanje u stručnoj literaturi i kliničkoj praksi koje ostaje bez odgovora. Do osamdesetih godina dvadesetog veka okluzivni faktori, kao što su određene malokluzije, razlike između retrudovanog kontaktnog položaja i interkuspalnog položaja veće od 2 mm, okluzivne smetnje (posebno mediotruzijske i retruzijske) i gubitak bočnih zuba, smatrali su se glavnim etiološkim faktorima u nastanku TMD. Cilj rada. Cilj rada je bio da se utvrdi uloga okluzivnih faktora u razvoju TMD i oceni uspeh primene ireverzibilne okluzivne terapije (selektivno brušenje) kod osoba sa TMD. Metode rada. U svrhu istraživanja pregledano je 200 osoba oba pola uzrasta 18-25 godina. Znaci i simptomi TMD su vrednovani na osnovu posebne funkcionalne analize i izraženi kraniomandibularnim indeksom (CMI) po Friktonu (Fricton) i Šifmanu (Schiffman). Na osnovu ovoga indeksa formirana je studijska grupa koju je činilo 15 ispitanika sa znacima i simptomima TMD. Kod njih je urađeno selektivno uklanjanje okluzivnih smetnji brušenjem prema metodi Oksona (Okeson) korišćenjem centralnog položaja kao referentnog položaja tokom okluzivne terapije. Vrednovanje CMI je ponovljeno trideset dana nakon okluzivnog uravnoteženja. Rezultati. Rezultati istraživanja su pokazali značajno smanjenje znakova i simptoma TMD posle okluzivnog uravnoteženja. Statističkom analizom je utvrđeno da između vrednosti CMI pre lečenja (CMI I) i trideset dana kanije (CMI II) postoji statistički značajna razlika. Vrednost CMI I bila je između 0,076 i 0,0346, dok je srednja vrednost bila 0,188±0,082. Vrednost CMI II bila je između 0,038 i 0,19, a srednja vrednost 0,038±0,053. Zaključak. Ova studija je potvrdila značaj ireverzibilne okluzivne terapije (selektivno brušenje) kod osoba sa TMD.