Is occlusal contact re-established within 6 months after bonding of a fixed anterior bite plane in adolescents with a Class II division 2 incisor relationship? A randomised controlled trial.

Abstract

Objective: To determine if re-establishment of occlusal contact was achieved within 6 months after insertion of a fixed anterior bite plane in individuals with Class II division 2 incisor relationship, and to evaluate the occlusal and vertical skeletal changes and acceptance of the intra-oral scanner and bite plane.

Design: Single-centre two-arm parallel group randomised controlled trial with 1:1 allocation to intervention and control groups.

Setting: Dundee Dental Hospital and Research School, UK.

Participants: A total of 38 participants aged 9-16 years (11 males, 27 females) with Class II division 2 incisor relationship and increased overbite (greater than one-third incisor overlap).

Methods: Participants were randomised to intervention (n = 19) and control (n = 19) groups using block randomisation. The intervention group had a fixed anterior bite plane, and the occlusion and vertical facial dimensions were monitored with intra-oral scans, lateral cephalograms and photographs. The control group received no treatment and occlusal and vertical facial dimensions were monitored with scans and photographs. Questionnaires were completed by participants and parents/carers. An intention-to-treat analysis was planned.

Results: The overbite reduced in all participants in the intervention group (mean initial overbite: 5.07 mm, 95% confidence interval [CI] = 4.15-6.00; mean overbite after 6 months: 2.45 mm, 95% CI = 1.93-2.96). There was a mean incisor intrusion of 0.29 mm (95% CI = 0.17-0.42) and mean eruption of the first molars of 0.23 mm (95% CI = 0.09-0.37). There was no significant change in incisor inclination or vertical skeletal change. Feedback from participants and their parents/carers were generally positive.

Conclusion: Fixed anterior bite planes effectively reduce an increased overbite in adolescents with a Class II division 2 incisor relationship, due to a combination of incisor intrusion and molar eruption with no change in incisor inclination or vertical skeletal change. Intra-oral scanning and fixed anterior bite planes are acceptable in adolescents.