Treatment effects of intrusion arches and mini-implant systems in deepbite patients

Abstract

The purpose of this study was to compare the skeletal and dental effects of 2 intrusion systems involving mini-implants and the Connecticut intrusion arch in patients with deepbites. The study sample consisted of 45 adults (26 women, 19 men) with deepbites. They were divided into 3 groups: 2 treatment groups and 1 untreated control group (15 subjects in each group). The Connecticut intrusion arch and the implant groups underwent maxillary incisor intrusion with Connecticut intrusion arches and a mini-implant system, respectively. During the 7-month study period, no other treatment was performed with the exception of maxillary incisor intrusion. The mean amounts of genuine intrusion were 2.20 mm (0.31 mm per month) in the Connecticut intrusion arch group and 2.47 mm (0.34 mm per month) in the implant group. No statistically significant differences were found in the extent of maxillary incisor intrusion between the 2 intrusion systems (P >0.05). Both systems led to protrusion and intrusion of the maxillary incisors (P <0.05), and protrusion and extrusion of the mandibular incisors (P <0.05). In the Connecticut intrusion arch group, the maxillary molars were extruded by moving the crown distally and the root mesially. The 2 intrusion systems were statistically different in the extent of alterations in the axial inclinations of the maxillary molars (P <0.05). Both the Connecticut intrusion arch and the mini-implant intrusion systems successfully intruded the 4 maxillary incisors. Although the movement of the maxillary molars led to the loss of sagittal and vertical anchorages during intrusion of the incisors in the Connecticut intrusion arch group, these anchorages were maintained in the implant and control groups.