Palatal implant supported versus conventional dental anchorage in adolescents

OBJECTIVES: Clinical comparison of the osseointegrated palatal implant (PI) supported anchorage with conventional dental anchorage (DA) for the two-phase retraction, in extraction cases requiring ‘maximum anchorage', in growing patients after post pubertal growth spurt. SUBJECTS AND METHODS: 30 patients selected with homogeneous facial skeletal characteristics (mean age: 14.22±1.37 years) were randomly allocated in two groups. In the PI group (n=15) Orthosystem® implants were placed into the palate for absolute anchorage and in each case a 1.2 x 1.2 mm thick rigid TPA was fixed to the implant and to the molar bands by laser welding. In the DA group (n=15) the maximal anchorage was provided by a TPA and a 0.017 x 0.025 inch SS utility arch. A super-elastic closed-coil spring was used for canine retraction. Sequential activation of the ‘teardrop' closing loop of the SS contraction arch was used for incisor ‘en mass' retraction. The main outcome measures were duration of the orthodontic treatment phases and cephalometric analysis of maxillary first molar movement. RESULTS: Insignificant difference (p=0.47) was observed between the groups regarding the duration of the extraction's gap closure. In the PI group the duration of the front retraction (p < 0.001) and the total treatment time was shorter (p < 0.05). No significant difference in molar mesial movement was found in both treatment phases even if the net molar anchorage loss was 4.35±1.69 mms in the DA group while 3.7±1.94 mms in the PI group. (p=0.35) CONCLUSIONS: Stable implant supported anchorage could be demonstrated, in conclusion the possible ‘maximum anchorage' was proved in this study. A shorter orthodontic treatment period was achieved by fastening the anchorage teeth to palatal implant, compared to dental anchorage. The use of palatal implant was without complication, representing a safe alternative in growing adolescents for ‘maximum anchorage' cases