Caries incidence following restoration of shortened lower dental arches ina randomized controlled trial

Context Removable partial dentures used to restore the shortened lower dent al arch may adversely affect the remaining natural teeth and are associated with a low prevalence of use. Objective To report the findings for caries incidence 2 years after restora tion of lower shortened arches with bilateral cantilever resin-bonded bridg es (RBBs) and conventional partial dentures (RPDs). Design Randomised controlled trial. Setting Secondary care Patients 25 male and 35 female subjects of median age 67 years. were random ly allocated to 'bridge' and 'denture' treatment groups of 30 patients each matched for age and sex. Caries incidence was recorded during dental exami nations 3 months, 1 and 2 years after insertion of new lower prostheses. In terventions Cantilever RBBs and conventional RPDs with cast metal framework s. Results There was a highly significant difference in the frequency of new c aries lesions, 11 and 51 in the bridge and denture groups respectively (P<0 .01). 20 out of 27 bridge patients and 9 of 23 denture patients had no cari es experience. Multivariate modeling identified treatment group as the only significant predictor of caries occurrences. Conclusions Two years after restoration of lower shortened arches for an el derly sample of patients, there was a significantly greater incidence of ne w and recurrent caries lesions in subjects restored with RPDs compared with cantilever RBBs.