Impact of morbid obesity on chewing ability

This study compared the chewing parameters in a group of obese adult patients scheduled for gastric bypass surgery with those of a control group.

Chewing parameters were measured in two groups of subjects, one of 44 obese patients scheduled for gastric bypass surgery (body mass index [BMI] = 49.1 +/- 7.2) and the other of 30 non-obese control subjects (BMI = 20.9 +/- 2.1). In both groups, the subjects' dental status was characterized by the number of functional dental units. Kinematic parameters, namely chewing time (CT), number of chewing cycles (CC), and chewing frequency (CF), were video recorded during the mastication of five natural standardized foods (banana, apple, sweet jelly, peanut, and carrot). The particle size distribution of the expectorated bolus from carrot and peanuts was characterized by the 50th percentile (D (50)). Analysis was carried out to detect any effect of the fixed factors "dental status," "type of food," and "subject group" on the variations of the dependent factors CT, CC, CF, and D (50).

In obese subjects, CT, CC, and D (50) were variables depending on both dental status and food. For fully dentate subjects, the group of patients with obesity showed higher values for CT and CC and lower values for D (50) for both carrot and peanuts than the control group.

The chewing parameters were affected in fully dentate patients with morbid obesity compared with controls, emphasizing the need for a systematic evaluation of both dental status and chewing ability in patients scheduled for bariatric surgery.