Changes in orthodontic treatment patterns within one orthodontic practice over a 15 year period.

Fifty consecutive treatment case records were analysed for each of the years 1964, 1971, 1974, 1976 and 1978. The following variables were examined: sex distribution, age at start of treatment, extractions undertaken (if any), type of appliance used, completeness or incompleteness of treatment, treatment duration and one final category termed "other clinical procedures' dealing with cephalometry, photography and surgery. The sex distribution fluctuated only slightly with a predominance of females throughout. The age of onset of treatment was fairly constant at around 12 years. Over the 15 years a rise in number of non-extraction cases was noted and the number of patients treated by extraction only, fell. The use of fixed appliances increased steadily and in 1978 55 per cent of cases received some form of fixed appliance therapy. The mean number of incomplete cases was 17 per cent for all years with no rise latterly despite the use of more complex appliances. The treatment duration time showed a steady decrease over the 15 year period. Few referrals for oral surgery were made, although the use of precision following rotation correction has increased.