Skeletal versus conventional intraoral anchorage for the treatment of class II malocclusion: dentoalveolar and skeletal effects

Abstract

BackgroundThe purpose of this retrospective study is to investigate the dentoalveolar and skeletal effects of two distalizing protocols featuring different anchorage systems used in patients with class II malocclusion: the MGBM system (skeletal anchorage) and Pendulum (intraoral anchorage).MethodsThe sample comprised 57 patients who were assigned to one of the two treatments: the MGBM group (30 patients, mean age 13.3 ± 2.3 years) or the Pendulum group (27 patients, mean age 12.8 ± 1.7 years). Three serial cephalograms were obtained at baseline (T0), after molar distalization (T1), and after fixed appliance treatment (T2). Esthetic, skeletal, and dental parameters were considered. Pancherz's superimposition method was used to assess sagittal dental changes. The initial and final measurements and treatment changes were compared by means of a paired t test or a paired Wilcoxon test. Statistical significance was tested at p < 0.05, p < 0.01, and p < 0.001.ResultsIn the MGBM group, the upper molar distalization was achieved in 7 months and showed a mean value of 4.9 mm (ms-PLO); the amount of molar relationship correction was 5.9 mm. In the Pendulum group, the upper molar distalization was obtained in 9 months and showed a mean value of 2.5 mm (ms-PLO), while the molar relationship correction amounted to 4.9 mm. Anterior anchorage loss occurred in both groups, although in the MGBM group, there was less mesial movement of the premolars.ConclusionsThe MGBM system and the Pendulum appliance are both effective in the correction of class II malocclusions. The MGBM system was found to be more efficient than the Pendulum appliance, producing greater molar distalization in a shorter treatment time.

Impact of molar teeth distalization with clear aligners on occlusal vertical dimension: a retrospective study

“…Looking at the results of this study, the upper molar distalization performed with clear aligners seems to overcome various side effects related with this orthodontic procedure typically observed with other appliances in previous studies [1,[7][8][9][10] and seems to allow a predictable distal body movement of upper molars [15][16][17] with a control of the vertical dimension and of the incisal torque. This could be related with the aligner design, that allows the control of 3D movements by holding teeth on all the surfaces (vestibular, palatal-lingual and occlusal) and applying proper forces thanks to properly digitally planned attachments.…”

“…Unfortunately this appliance requires considerable patient compliance [3,4] so several alternative intraoral methods had been proposed to reduce or cut out patient's cooperation [5,6]. Despite the effectiveness of many of these appliances clinicians must consider many sideeffects: increase in lower face height, clockwise mandibular rotation, extrusion of first premolars, undesirable tipping of the maxillary molars and loss of anterior anchorage during distalization [1,[7][8][9][10]. Most of these side effects involve an increase of the vertical dimension of the treated subjects, keeping this treatment procedure generally contraindicated in hyperdivergents [2,11].…”

Comparison between direct vs indirect anchorage in two miniscrew-supported distalizing devices

“…20 On the contrary, DS showed greater distalization time 21 (9 6 2 months) and a smaller amount of molar distalization (3.2 mm), but a more bodily distalization (23u; 95% CI 5 24.8, 21.9), possibly as a result of the rigidity of the appliance, which, acting as the Distal Jet, 3 was able to direct the force in proximity to the center of resistance of the first molar exploiting the bayonet bend and telescopic rigid arms (Figure 2). However, the main difference between MGBM and DS was represented by the premolar movement (Figures 4 and 5).…”

Maxillary molar distalization with miniscrew-supported appliances in Class II malocclusion: A systematic review

“…Miniscrew-supported appliances have experienced widespread clinical use and various studies have demonstrated their skeletal and dentoalveolar effects. 6,7,10,[15][16][17][18][19][20][21][22][23][24][25][26][27] The present systematic review was conducted to examine the effectiveness of miniscrewsupported appliances for maxillary molar distalization in Class II malocclusion. 21 Prospective 2 MS/Subject (24) Miniscrews placed in the interradicular space Polat-Ozsoy et al, 2008 20 Retrospective BAPA/HP one or 2 MS/subject (31) BAPA/HP Escobar et al, 2007 19 Prospective BSP, 2 MS/subject (30) BSP Gelgor et al, 2007 25 Prospective MSV/MSP one per subject (40) VFV/PFV Kircelli et al, 2006 17 Prospective BAPA, 1 MS/Subject (10) BAPA Gelgor et al, 2004 24 Prospective /One per subject (25) Intramaxillary fixation screw a MS indicates miniscrew; SD, self drilling; ST, self tapping; SDJ, skeletonized distal jet; MD, molar distalization; PMD, premolar distalization; AL, anchorage loss; MISDS, miniscrew implant-supported distalization system with two miniscrews per subject; BAPA, bone-anchored pendulum appliance; MGBM, MGBM system with interradicular miniscrew; DS, distal screw appliance with palatine miniscrew; DJ, distal jet appliance; HP, Hilgers Pendulum; MSV, miniscrew with vestibular force; MSP, miniscrew with palatal force; VFV, vestibular force vector appliance; PFV, palatinal force vector appliance; BSP, bone-supported pendulum.…”

“…10 In searching the literature, there were a few systematic reviews 12,13 and a meta-analysis 14 conducted on the success rate and anchorage quality of miniscrew implants. Except for several studies that showed the effectiveness of the miniscrew-supported appliance in molar distalization, 6,7,[15][16][17][18][19][20][21][22][23][24][25][26][27] there was no systematic review synthesizing the evidence for the use of a miniscrew in molar distalization. To address this, a systematic review of the literature was conducted to evaluate the quantitative effects of the miniscrewsupported appliance in maxillary molar distalization in Class II malocclusion.…”