Introduction: Patients with masticatory dysfunction have a higher incidence of gastrointestinal disorders including gastroesophageal reflux disease (GERD). Masticatory function is significantly lower in patients with skeletal Class III malocclusion than in those with normal occlusion. However, GERD symptoms in patients with skeletal Class III malocclusion are still unknown. The purpose of this study was to examine GERD symptoms and masticatory functions in patients with skeletal Class III malocclusion.
Methods: Nineteen adult patients with severe skeletal Class III malocclusion (Class III group) and 20 adults with normal occlusion (control group) participated in this study. The results of the Carlsson-Dent self-administered questionnaire (QUEST) and the frequency scale for the symptoms of GERD (FSSG) were compared between the 2 groups, along with occlusal contact area, maximal voluntary bite force, and salivary flow rate.
Results: The QUEST and FSSG scores were significantly higher in the Class III group. Occlusal contact area and maximal voluntary bite force were significantly smaller in the Class III group. There was no significant difference in the salivary flow rates between the groups.
Conclusions: GERD symptoms were observed more often in patients with skeletal Class III malocclusion than in normal subjects as determined by the questionnaires.