Comparison of treatment effects between the modified C-palatal plate and cervical pull headgear for total arch distalization in adults

Abstract

ObjectiveThe purpose of this study was to evaluate the dental and skeletal effects of the modified C-palatal plate (MCPP) for total arch distalization in adult patients with Class II malocclusion and compare the findings with those of cervical pull headgear.MethodsThe study sample consisted of the lateral cephalograms of 44 adult patients with Class II Division 1 malocclusion, including 22 who received treatment with MCPP (age, 24.7 ± 7.7 years) and 22 who received treatment with cervical pull headgear (age, 23.0 ± 7.7 years). Pre- (T1) and post-treatment (T2) cephalograms were analyzed for 24 linear and angular measurements. Multivariate analysis of variance was performed to evaluate the changes after treatment in each group and differences in treatment effects between the two groups.ResultsThe mean amount of distalization at the crown and root levels of the maxillary first molar and the amount of distal tipping was 4.2 mm, 3.5 mm, and 3.9° in the MCPP group, and 2.3 mm, 0.6 mm, and 8.6° in the headgear group, respectively. In addition, intrusion by 2.5 mm was observed in the MCPP group. In both groups, the distal movement of the upper lip and the increase in the nasolabial angle were statistically significant (p < 0.001). However, none of the skeletal and soft tissue variables exhibited significant differences between the two groups.ConclusionsThe results of this study suggest that MCPP is an effective treatment modality for total arch distalization in adults.

Comparison of treatment effects between four premolar extraction and total arch distalization using the modified C-palatal plate

“…The maxillary incisor in the MCPP group was vertically extruded by 1.03 mm and the mandibular incisor was vertically intruded by 1.11 mm from the HRL, with a net result of 0.64 mm of overbite reduction. This extrusion of the maxillary incisor was consistently described as one of the effects of the MCPP, 20 21 22 and this may suggest that, in challenging deep bite cases, the MCPP should be used with additional bite-opening mechanics, such as intrusion arches or miniscrews, for better vertical control. On the other hand, such movement may serve as an additional advantage when the treatment goal is to increase the amount of overbite or display of maxillary incisors in relation to the upper lip line.…”

“…The efficiency of TADs to distalize the whole dentition has been well characterized in the literature. 8 9 10 11 13 15 16 17 18 19 20 21 22 28 29 Reportedly, the amount of maxillary incisor retraction varied from the stationary position to 3.3 mm, mostly falling in the range near 2 to 3 mm. A few studies have even reported mild labial movement of the maxillary incisors after the use of TADs, such as miniscrew-supported skeletal distal jet.…”

“…In this study, the maxillary first molar of the MCPP group was distalized by 3.97 mm, which was in accordance with that reported in previous investigations. 20 21 22 While the retraction amount described by most studies fell in the range of 2 mm to 4 mm, Kircelli et al 18 showed that their bone-anchored pendulum appliance successfully distalized the maxillary first molars by 6.4 mm in adolescent patients. In contrast, Oh et al 29 reported 1.5 mm of molar retraction assisted by buccal miniscrews in adults.…”

“…Also, it has been demonstrated that MCPPs could be effectively used for up to 4 mm of distalization of the maxillary first molars in adults. 22 This finding may imply that the application of MCPPs could preclude IPR and possibly the extraction of premolars in cases in which these were previously required. Since only the residual space after resolving the arch-length discrepancy may be utilized to improve the molar relationships, the requirement for the amount of molar retraction may be more stringent in correcting Class II malocclusion rather than Class I malocclusion.…”

Finite Element Analysis of Stress in Maxillary Dentition during En-masse Retraction with Implant Anchorage

“…Many clinical studies 11,25) and biomechanical analyses have investigated posterior movement of the anterior teeth using implant anchorage. Few clinical reports 22,28) and biomechanical analyses 2,3,9,31) regarding en-masse retraction of the entire maxillary or mandibular dentition are available, however. Nonetheless, understanding the biomechanical variables associated with implant anchors in orthodontics is very important, because the height and position of the hooks and implant anchors affect tooth movement.…”