Tooth wear of anterior teeth during and after orthodontic treatment

OBJECTIVES: to study occlusal wear of anterior teeth in patients treated orthodontically and retained with different types of retainers until 5 years post-treatment and to study if type of retention influences occlusal wear

METHODS: 226 consecutive orthodontic patients from the Orthodontic Department, Radboud University Nijmegen Medical Center, aged 15 years maximally at start of treatment, without dental trauma, replacements or agenesis were followed until 5 years post-treatment. Two types of lower retainers were used: a lingual retainer bonded on all anterior teeth or on canines only. In the maxilla a retainer bonded on all six teeth or a removable retainer was used. Dental casts were analysed before treatment (Ts), after treatment (T0) and five years post-treatment (T5). Crown wear of incisors and canines was scored at the three stages applying a grading scale. Intercanine width, overjet, overbite were measured with an electronic calliper. Statistics: Paired sampled t-test for differences over time; Pearson correlation coefficients for associations between wear and retention type; backward linear regression for influence of retention type on occlusal wear.

RESULTS: During all time periods there was an increase in wear and for all teeth males showed more tooth wear than females. From Ts-T5 gender and maxillary retention accounted for 11% of the changes in canine wear. Increase in lower intercanine width also had an influence on canine wear (T0-T5). Incisal wear was associated with increase in lower intercanine width (T0-T5), type of maxillary retention (Ts-T5) and type of mandibular retention (T0-T5). In the mandible more incisal wear was found in patients with a C-C retainer bonded on canines only. In the maxilla more wear was found in patients with a removable retainer.

CONCLUSION: Gender, retention type and occasionally increase in intercanine width influence occlusal wear of anterior teeth after orthodontic treatment.