The effect of tooth borne versus skeletally anchored Alt-RAMEC protocol in early treatment of Class III malocclusion: a single-centre randomized clinical trial.

Abstract

This was a randomized, controlled trial designed to compare outcomes between the use of dental and skeletal anchorage, using the Face mask/Alternate Rapid Maxillary Expansion and Contraction (FM/Alt-RAMEC) protocol. The study was carried out at Mater Dei Hospital, Malta and included prepubertal skeletal Class III malocclusion patients where the aetiology was primarily maxillary hypoplasia. Two groups were assigned. Group I was treated with FM/Alt-RAMEC and group II was treated with skeletally anchored FM/Alt-RAMEC. Wear-time (WT) of the FM was monitored using TheraMon microsensors. Patients were instructed to wear the FM for 12-14 hours/day for 9 months. Changes were evaluated with lateral cephalograms and analysed with Wilcoxon and Mann-Whitney U tests. ANOVA was used to analyse the effect of gender on compliance parameters. Spearman's correlation coefficient was used to assess the correlation between compliance and skeletal changes. To compare the skeletal and dentoalveolar changes in patients treated with these two protocols. The primary outcome was to assess skeletal and dentoalveolar outcomes in patients treated with skeletally anchored FM/RME and tooth-borne FM/RME; utilizing Alt-RAMEC protocol. The secondary outcome was compliance rate and adherence to FM wear among patients. Randomizer software and the sealed envelope technique were used to randomly allocate patients 1:1 into either group I (tooth-borne FM/Alt-RAMEC) or group II (skeletally anchored FM/Alt-RAMEC). It was not possible to blind to treatment allocation, but blinding was used when assessing the outcomes. Numbers randomized and analysed. Thirty-five patients were allocated. Group I consisted of 18 subjects and group II consisted of 17 subjects. One patient in group I dropped out due to illness, so 17 subjects in each group completed the study. Post-treatment changes in group I showed significant increases in SNA (2.10°), ANB (3.90°), Wits (4.70 mm), and overjet (5.40 mm). Group II showed significant increases in ANB (3.10°), Wits (3.20 mm), and overjet (4.50 mm). Wearing time for group I patients was 7.87 ± 2.88 hours/day and for group II was 6.98 ± 2.68 hours/day, with no significant difference between the groups. Lack of long-term follow-up post-treatment, making the conclusion applicable only in the short term. No harm was observed in both groups. Despite the large difference between the measured and the patient-reported daily WT, both tooth-borne and skeletally anchored FM/Alt-RAMEC showed positive, similar, skeletal and dental effects. ISRCTN12197405.