Incidence of partial denture usage and Kennedy classification

Objectives:

Although implant supported prostheses are becoming more common, removable partial dentures (RPDs) are still one of the main options for partially edentulous patients. The classification of dental arches is to simplify the description of combinations of teeth and ridges and useful for diagnosis, prognosis, and denture design in each group.

The purpose of this study was to exam the relation between type of partially edentulous dental arches according to Kennedy classification and the rates of denture usage among independently-living elderly.

Methods:

The study population were 1662 independently-living, cognitively healthy persons over 60 years [66.2 ± 4.2 years (SD)]. Dental examinations were done by ten calibrated dentists. Partially edentulous arches were divided according to Kennedy classification. The subjects were examined whether they wore a removable denture or not, and were asked their satisfaction with prostheses.

Result:

About half of the subjects had fully dental arches including fixed restorations both in maxillae and mandibles. Completely edentulous arches were 6.0% in the maxillae and 3.3% in the mandibles. In maxillae, the dental arches of Kennedy class I, II, III, and IV were 15.9%, 22.3%, 7.6%, and 1.1% of total population, respectively. In mandibles, those were 15.4%, 22.0%, 12.7%, and 0.5%. Denture usage rate was significantly higher in arches of Kennedy class I than those of II both in maxillae and mandibles (Chi-square test, P<0.05). On the other hand, satisfaction with RPDs was not significantly different between Kennedy class I and II.

Conclusion:

Our results indicated that majority of partially edentulous dental arches were Kennedy class I or II and the rate of usage RPDs was lower in Kennedy class II among independently living elderly Japanese. This study was supported by a Grant-in-aid for Scientific Research (19390496) from the Japan Society for the Promotion of Science.