Chewing ability of subjects with shortened dental arches.

OBJECTIVES: The objective was to study chewing ability in subjects with shortened dental arches in Tanzania.
METHODS: A sample of 725 adults with shortened dental arches comprising intact anterior regions and 0-8 occluding pairs of posterior teeth and 125 adults with complete dental arches were recruited. Subjects were classified into nine categories according to arch length and symmetry. Chewing ability was investigated by interview on chewing complaints and on perceived difficulty of chewing 20 common Tanzanian foods, 12 soft, and 8 hard.
RESULTS: Categories with extreme shortened arches (0-2 pairs of occluding premolars) reported most frequent (95-98%) and most severe complaints ('cannot chew all foods' or 'have to use special or specially prepared food'). Categories with intact premolar regions and at least one occluding pair of molars had nearly no complaints (95-97%). The other arch categories had an intermediate volume of complaints (33-54%). Perceived difficulty of chewing deteriorated with a decrease of occluding pairs of teeth. Subjects with 0-2 pairs of occluding premolars had major difficulties with chewing. Subjects with 3-4 pairs of occluding premolars or asymmetric arches comprising a short side with none or one pair of premolars and a long side including at least one occluding pair of molars had more difficulties with chewing compared to subjects with more complete dental arches. As a whole, they perceived for hard foods, 'minor problems, not adapted'.
CONCLUSIONS: Shortened dental arches with intact premolar regions and at least one occluding pair of molars provide sufficient chewing ability. Shortened arches with 3-4 pairs of occluding premolars and asymmetric arches with a long side result in impairment of chewing ability, especially for hard foods. In extremely shortened arches comprising 0-2 occluding premolars, chewing ability is severely impaired.