How Many Teeth are Extracted as Part of Orthodontic Treatment? A Survey of 2038 UK Residents

Background: The extraction rate is defined as the number of patients having permanent teeth extracted as a percentage of the total treatment sample. Reports of extraction rate in the literature vary dramatically from 0.2 % to 80 %. Over the last 20 years these appear to have reduced to lower levels owing to the popularity of non-extraction orthodontics. Objective: Previous estimates of extraction rates have been based on restricted groups which may well introduce bias. To avoid this the present study was undertaken to look at a random sample of the general population. Method: A questionnaire survey was conducted on a random sample of the UK wide population using an online survey. Results: Surprisingly high rates were found for extraction of 1 to 6+ teeth, 50 % for 18-24 years and 75 to 80 % for all other age groups. There was no difference between males and females (p=0.217) or between different age groups (p=0.738). Third molar extractions were significantly greater in the older age groups (p=0.000) whilst there was no difference for impaction with age (p=0.230). Conclusion: The dramatic variation in extraction rates reported over the last 100 years was not reflected in the general population where there was no change with age. Rates were vastly greater than expected from those currently reported in the literature. The significant reduction in third molar removal in the younger age groups could well indicate the influence of NICE guidelines.