Masticatory performance is not associated with diet quality in Class II orthognathic surgery patients.

This study evaluated the association between masticatory function, diet, and digestive system problems in 59 Class II patients 5 years after bilateral sagittal split osteotomy. Dietary intake data were recorded in 4-day diet diaries and analyzed for overall diet quality (Healthy Eating Index) and selected dietary components. Masticatory function was assessed through measurements of masticatory performance, maximum bilateral bite force, and chewing time and number of chewing strokes until the subject felt that the bolus was ready to swallow. Self-reported frequency of digestive system problems was recorded with a 7-point Likert scale questionnaire. Masticatory function was not associated with diet quality or gastrointestinal problems. There was a weak association between intake of foods that require chewing (eg, fiber, protein, meat, and vegetables) and masticatory variables. Fourteen subjects (24%) had a poor diet and 45 subjects (76%) had a diet that needed improvement according to the Healthy Eating Index. Self-reported constipation was the only digestive system problem that was significantly associated with masticatory performance.