The first 100 cases: a personal audit of orthodontic treatment assessed by the PAR (peer assessment rating) index.

The first 100 consecutively started cases treated by a specialist registrar in orthodontics were examined and pre- and post-study models were scored using the peer assessment rating (PAR) index. The PAR index proved both simple and reproducible to use: 92 cases had post-treatment records available, 91 patients registered a drop in PAR score, and one patient registered an increase. Of these 92 patients, 38 (41%) were greatly improved, 43 (47%) were improved, and 11 (12%) were made worse or no different (ie they failed to achieve a 30% drop in PAR score). Of the factors examined, only the appliance type used was significantly related to PAR score change. Of the 11 cases apparently made worse, individual examination revealed that four of these represented beneficial occlusal changes but due to limited treatment goals they did not register as improved using the PAR index according to previously agreed criteria. The PAR index measures 'good tooth position' which, although very important, is not the only factor in orthodontic treatment. The use of the PAR index to detect 'good' and 'bad' orthodontic treatment is not without problems. Its use in mixed dentition and adjunctive orthodontic treatments may not always be appropriate.