Persons with a shortened dental arch (SDA) have a dentition characterized by a reduction or absence of (pre)molars starting posteriorly (1). As a result, their chewing platform area is reduced. It has been well established that chewing performance, as measured with chewing tests, declines linearly with decrease of the chewing platform area (2±6). It can therefore be anticipated that the reduction in the number of posterior teeth as in SDAs will lead to dif®culties with chewing. However, a number of studies indi- cate that majority of the people with a reduced number of posterior teeth report their chewing abil- ity to be satisfactory as long as 20 `well-distributed teeth' are present (7±11). In case of SDA, this was observed when at least 3±4 occluding pairs of teeth are present, preferably in a symmetrical position (2, 12, 13). In a longitudinal study in the Netherlands, about 10% of these subjects reported complaints on chewing function, namely they had to chew longer or had to swallow food coarsely (14). It has been argued that the importance of chewing for food pulverization has declined because of avail- ability of food industries and modern means of food preparation (15, 16). This might be valid in indus- trialized countries where pre-processed or re®ned food is available, and people have a broad variety of foods. In nonindustrialized countries, diet is largely composed of agrarian products and methods of food preparation might be limited. Consequently, pulveri- zation of food might need more intensive chewing in these countries than in industrialized countries. Our hypothesis, therefore is that an SDA comprising of Community Dent Oral Epidemiol 2003; 31: 328±34 Printed in Denmark. All rights reserved 328 Chewing ability of subjects with shortened dental arches Sarita PTN, Witter DJ, Kreulen CM, Van't Hof MA, Creugers NHJ. Chewing ability of subjects with shortened dental arches. Community Dent Oral Epidemiol 2003; 31: 328±34. ß Blackwell Munksgaard, 2003 Abstract ± 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 classi®ed into nine categories according to arch length and symmetry. Chewing ability was investigated by interview on chewing complaints and on perceived dif®culty 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 dif®culty of chewing deteriorated with a decrease of occluding pairs of teeth. Subjects with 0±2 pairs of occluding premolars had major dif®culties 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 dif®culties 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 suf®cient 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. Paulo T. N. Sarita 1 , Dick J. Witter 2 , Cees M. Kreulen 2 , Martin A. Van't Hof 3 and Nico H. J. Creugers 2 1 Department of Restorative Dentistry, Faculty of Dentistry, Muhimbili University College of Health Sciences, Dar es Salaam, Tanzania; 2 Department of Oral Function and Prosthetic Dentistry, 3 Department of Preventive and Community Dentistry, Medical Faculty, College of Dental Sciences, University of Nijmegen, Nijmegen, the Netherlands Key words: dental arch; dental occlusion; mastication Dick J. Witter, Department of Oral Function and Prosthetic Dentistry, College of Dental Sciences, University of Nijmegen, PO Box 9101, 6500 HB Nijmegen, the Netherlands Tel: 31 24 3614004 Fax: 31 24 3541971 e-mail: [email protected]Submitted 26 February 2002; accepted 9 October 2002
