Twin Block appliance with acrylic capping does not have a significant inhibitory effect on lower incisor proclination

Abstract

Objective: To investigate the effect of acrylic capping, treatment duration, overjet, and lower incisor inclination on the posttreatment tooth position in patients treated with 2 Twin Block (TB) appliance versions. Materials and Methods: Cephalograms of 56 patients with Class II malocclusion (21 boys, 35 girls; mean age before treatment [T1] ¼ 12.5 years; standard deviation, 0.7) treated with a TB appliance with either acrylic capping or ball-ended clasps on lower incisors were retrospectively collected and traced. Lower incisor inclination (L1-GoGn, L1-GoMe, L1-MP) was measured at T1 and after TB appliance removal (T2). Regression analysis was performed to evaluate the effect on the lower incisor inclination of appliance type, overjet, lower incisor inclination at T1, and treatment duration after adjusting for baseline measurements. Results: Appliance design was not a significant predictor for either incisor inclination measurement (P, .05). Pretreatment lower incisor inclination was the only factor significantly associated with final tooth inclination (L1-GoGn: b ¼ 0.57, 95% confidence interval [CI] ¼ 0.30, 0.84, P , .001; L1-GoMe: b ¼ 0.56, 95% CI ¼ 0.28, 0.84, P , .001; L1-MP: b ¼ 0.46, 95% CI ¼ 0.17, 0.75, P ¼ .003). There was weak evidence that treatment duration excluding L1-MP (95% CI ¼ -1.85, -0.02; P ¼ .045) and overjet might be associated with inclination of lower incisors at T2. Conclusions: TB appliance design with acrylic capping on lower incisors appears not to significantly control incisor proclination. Pretreatment lower incisor inclination may be significantly associated with tooth inclination after active TB treatment and should be considered in treatment planning. (Angle Orthod. 2017;87:513-518)

Concurrent validity and reliability of cephalometric analysis using smartphone apps and computer software

“…Interestingly, CephNinja, unlike OneCeph, 20,21 c Values with unacceptable reliability (ie, ,.7). 19 does not have incorporated features to assist the user with relocating points on the mobile touchscreen in case of wrong identification. Evaluation of cephalometric measurements deriving from two apps installed on an iPad (ie, CephNinja and SmartCeph) compared with Pro Dolphin Imaging computer software showed statistically significant differences in 56.3-62.5% of the measurements.…”

“…The free versions of the CephNinja and OneCeph 15 apps were downloaded from the Google Play Store on March 30, 2018 (Google Inc, Mountain View, Calif) on a Samsung Galaxy S8 smartphone (Samsung Telecommunications, Suwon, South Korea). Viewbox, a CE-certified computerized cephalometric analysis program broadly used in orthodontic research, [16][17][18][19] was installed on a laptop (Microsoft Surface Laptop Core, i8, 8-256 GB, Microsoft Corporation, Redmond, Wash) and served as the gold standard. To eliminate interobserver variability and to focus on the intertool variability, a single examiner (Dr Livas) traced the radiographs randomly first using Viewbox, then One-Ceph, and finally CephNinja.…”

“…At the time the study was conducted, the examiner had 15 years of clinical experience in orthodontics and more than 10 years of experience using Viewbox and has been previously calibrated. [16][17][18][19] Prior to the study, a 3-hour training for each app was carried out to allow the examiner to master the tracing method. As the vast majority of smartphones are not equipped with a stylus, identification of landmarks was performed directly on the touchscreen by a finger to represent mainstream use.…”

Evaluating the effects of functional orthodontic treatment on mandibular osseous structure using fractal dimension analysis of dental panoramic radiographs

“…[1][2][3][4] In their study investigating the long-term effects of protrusive function, McNamara and Bryan 5 reported that mandibular length increased with remodeling of the posterior and postero-superior surfaces of the condyle. Contrary to these studies, other authors [6][7][8] reported that functional orthopedic treatment induced little change in the bony elements of the craniofacial system and argued that the effect was limited to the dentoalveolar region. Discrepancies between the findings reported in these studies may be attributable to the variety of measurement methods used, as well as to the fact that most measurements were based on cephalometric radiographs and could not reflect changes in the osseous structure of the mandibular region.…”

Comparison between Classic Twin-block and a Modified Clear Twin-block in Class II, Division 1 Malocclusions: A Randomized Clinical Trial

“…11 Various design and modification of twin-block appliances have been used to decrease this side effect. 2,5,12 Treatment effects of removable orthodontic appliances, irrespective of the particular individual therapeutic intervention and mode of action largely depend on the patient cooperation. 13 One of the most important factors on patients' cooperation is the appearance of the appliance that may be unpleasant in social interactions.…”