Specialist orthodontics in the General Dental Service.

This study investigated treatment times and treatment standards produced by 10 specialist orthodontic practitioners working in the General Dental Service (GDS) in England. Twenty cases from each practitioner, consecutively completed with two-arch fixed appliance therapy, were selected and assessed to evaluate treatment times and treatment standards. Observer-generated timings were recorded to provide values for the time taken by these practitioners to perform the various component activities associated with fixed appliance orthodontic therapy. These timings were then pooled to produce an 'average' value for each procedure. Treatment time was assessed retrospectively by applying these average times to the appropriate appointments, as documented on the patient's record card. The treatment duration, number of visits, appliance type and extraction regime were also recorded. Treatment standards were assessed by applying the weighted Peer Assessment Rating Index (PAR Index) to pre- and post-treatment study casts. Relationships between each of these variables were investigated using multiple regression analysis. No relationship was found between treatment time and PAR score change. Predictors of treatment time were the number of visits, and more interestingly, the use of extra-oral forces. However, no useful predictors of the treatment standard were found. On the basis of this sample, it appears that when specialist orthodontic practitioners in the GDS provide two-arch fixed appliance therapy: treatment is completed, on average, in 3-5 hours of chairside time, in 20 visits, spread over 22 months; they provide a high standard of treatment, as assessed by the PAR Index, to a caseload of patients in need to treatment.