Effects of orthodontic reconstruction on brain activity in a patient with masticatory dysfunction

Abstract

Brain functional magnetic resonance imaging (fMRI) was used to evaluate the effect of malocclusion therapy on the brain activity of a patient with malocclusion. A 29-year-old female patient had difficulty opening the mouth with occasional pain in the left temporomandibular joint (TMJ) and a maximum opening of only 29 mm. The treatment objectives included repositioning the displaced mandible and establishing occlusal support. Orthodontic treatment took 14 months. Treatment results were satisfactory in terms of the occlusion and function of the TMJ as well as aesthetics. Analyses of brain activity using fMRI before and after orthodontic treatment indicated clenching at the habitual intercuspal position (ICP) before treatment resulted in increased blood oxygen level dependent (BOLD) signals in the motor area of the oral region abnormally; however, this activity converged after treatment. These results suggested orthodontic treatment of malocclusion may relieve unpleasant symptoms.

Correlation of Occlusal-Plane-Inclination with Functional Condylar Displacement in Different Skeletal Classes

“…A steep anterior occlusal plane [54] involves an avoidance pattern [55] due to the avoidance of too strong front tooth contacts in the transversal, retrusive or protrusive direction [56], leading to a load of the structures of the temporomandibular joint [57,58] and to a constant hypertonicity of the muscles. This additional load involves a neurological reaction of the body leading to even more muscle activity [26,1,39]. Moreover, in the majority of cases a steep posterior occlusal plane provides a significantly higher chance for the occurrence of laterotrusive and mediotrusive or even retrusive posterior interferences [59], again making an avoidance-which in turn will lead to more compensatory necessity of the system to increase the activity of the neurological system, enhanced muscle activity [60] and condylar displacement.…”

“…Two subtypes of Dist occlusion are Class II, Division 1 with protruded upper anterior teeth and Class II, Division 2: here the Based on the concepts of occlusion by Professors Slavicek and Sato [26], we have taken up the case study of several patients in this thesis.…”

Influence of restoration adjustments on prefrontal blood flow

“…Some studies have reported that many patients with malocclusion complaints experience comorbid mental stress and somatic symptoms [ 1 – 3 ]. Additional studies have suggested that malocclusion may be linked to higher brain function [ 4 – 6 ]. An experimental animal study induced occlusal disharmony in rats by attaching metal wires to the biting surfaces of both maxillary molar teeth with resin cement to artificially raise the vertical dimension of occlusion (VDO).…”

“…Current methods used to measure human brain function in medical and clinic research include positron emission tomography (PET), magnetoencephalography (MEG), fMRI, and near-infrared spectroscopy (NIRS). These neuroimaging techniques have also been used in the field of dentistry to study the effects of various oral functions on the brain [ 4 , 5 , 11 – 20 ]. However, the results of this research have yet to be translated into clinical dental applications, since the aforementioned systems are often expensive and difficult to operate, while fMRI and MEG require the patient’s head to be secured and the patient’s posture to be limited.…”