The aim of this randomized controlled clinical trial is to evaluate the dentoalveolar and skeletal treatment effects of the AMDA when used for distalization of the maxillary first molars in patients with Class II malocclusion in the permanent dentition.

The primary aim is to evaluate two different treatment groups from initiation of treatment up until completion of maxillary molar distalization of:

• Group I: patients treated with amda®
• Group II: patients treated with buccal mini-implants

More specifically to evaluate the efficiency of the AMDA using lateral cephalograms and digital 3D model casts of the patients under investigation at the following time points:

• point T0: baseline data - before initiation of the treatment
• point T1: immediately after distalization (8-12 months)

Inclusion Criteria:

• All patients to have permanent dentition
• with or without the 2nd molar erupted
• bilateral Class II molar relationships (a quarter to 1 molar cusp).

Exclusion Criteria:

• Past orthodontic treatment
• crossbites,
• severe carious lesions,
• poor oral hygiene,
• mobility of the maxillary first molars,
• anterior open bites,
• vertical growth pattern,
• tongue habits.

The data will be availaible upon request