Prospective study of dentoskeletal changes in Class II division malocclusion treatment with twin force bite corrector

Abstract

Objective: To evaluate the dentoskeletal changes of Class II malocclusion treatment with the Twin Force Bite Corrector (TFBC). Materials and Methods: The sample comprised 86 lateral cephalograms obtained from 43 subjects with Class II division 1 malocclusion; the subjects were divided into two groups. The experimental group comprised 23 patients with a mean initial age of 12.11 years who were treated with the TFBC for a mean period of 2.19 years. The control group included 40 lateral cephalograms from 20 Class II nontreated patients, with an initial mean age of 12.55 years and a mean observation period of 2.19 years. The lateral cephalograms were evaluated before and after orthodontic treatment in group 1 and in the beginning and end of the observation period in group 2. t-Tests were used to compare the initial and final cephalometric characteristics of the groups as well as the amount of change. Results: The experimental group presented greater maxillary growth restriction and mandibular retrusion than the control group, as well as greater maxillomandibular relationship improvement and greater labial tipping of the mandibular incisors. The results also showed a greater decrease in overbite and overjet in the experimental group, and there were no statistically significant differences in the craniofacial growth pattern between groups. Conclusions: The TFBC promotes restriction of anterior maxillary displacement without significant changes in mandibular length and position and improvement of maxillomandibular relationship without changes in facial growth and significant buccal tipping of mandibular incisors. Class II correction with the TFBC occurred primarily as a result of dentoalveolar changes.

Evaluation of the Treatment Outcomes for Class II Malocclusion by Using PowerScope Appliance

“…Also upper incisor inclination to NA and upper incisor position relative to NA were significantly decreased. These results agreed with other studies on PowerScope (6,8) .Similar results were reported with TFBC (14)(15)(16) with AdvanSync (12,13) and with Eureka Spring (20) .…”

“…This reduction in overbite might be attributed to proclination of the lower incisors in combination with the anterior edge to edge relationship which left the buccal segment out of occlusion and gave the chance for normal buccal segment vertical growth. Studies on TFBC reported reduction in the overbite with a mean value of -3.2mm (15,16) which is very close to the results of this study. Significant decrease for the overbite with a mean value -2.4mm was reported from a study on Herbst appliance (21,22) and another study on Jasper Jumper appliance (24) Regarding the inter-incisal angle, this study showed significant increase with a mean of 10º.…”

“…This effect is often observed with the use of fixed functional appliances, similar finding in other studies was reported after using PowerScope in treatment of Class II malocclusion (6,7) significant reduction in SNA was also reported with the use of Herbst appliance (10) as well as with Jasper Jumper (11) and after treatment with AdvanSync appliance (12,13) Regarding the mandible there was significant anterior displacement demonstrated by statistically significant increase in SNB (P<0.001), Similar finding was reported in other studies using PowerScope Class II corrector (6)(7)(8)(9) same results were demonstrated with TFBC (14)(15)(16) and also with Herbst appliance (5,10,22) and with mandibular protraction appliance (17) . However other studies demonstrated different results as with MARA (18) .…”

Mechanism of Class II correction in prepubertal and postpubertal patients with Twin Force Bite Corrector

“…The study design was retrospective and involved a systematic analysis of all Class II patients treated with the TFBC appliance 16,17 Subjects fulfilling the following requirements were selected: (1) Class II molar relation, defined as having at least an ''end on'' molar relation with no subdivision malocclusion, (2) ANB angle $ 3.5u, (3) SN-GoGn # 36u, (4) Overjet $ 3.5 mm, and (5) up to 3-4 mm crowding or spacing. The initial data pool consisted of 51 consecutively treated Class II patients who were divided into two groups of prepubertal and postpubertal samples based on the modified cervical vertebral maturation stage (CVMS) by Bacetti et al 18 This method was chosen because appearance of concavity at the lower border of C4 (which occurs at onset of stage III, ie, past the pubertal growth spurt) is easily identifiable.…”

Long-term surgical versus functional Class II correction: A comparison of identical twins

“…To minimize the mandibular incisor proclination during the fixed functional appliance phase, mandibular incisor brackets with 26u torque were used. The Twin Force Bite Corrector (TFBC) appliance [17][18][19] was used for 10 months for Class II correction (Figure 4). The patient was in a super Class I molar relation with anterior edge-to-edge incisal relationship to compensate for mild relapse after removal of the TFBC appliance.…”