Angle class II correction with MARA appliance

Objective: To assess the effects produced by the MARA appliance in the treatment of Angle’s Class II, division 1 malocclusion. Methods: The sample consisted of 44 young patients divided into two groups: The MARA Group, with initial mean age of 11.99 years, treated with the MARA appliance for an average period of 1.11 years, and the Control Group, with initial mean age of 11.63 years, monitored for a mean period of 1.18 years with no treatment. Lateral cephalograms were used to compare the groups using cephalometric variables in the initial and final phases. For these comparisons, Student’s t test was employed. Results: MARA appliance produced the following effects: Maxillary growth restriction, no change in mandibular development, improvement in maxillomandibular relationship, increased lower anterior facial height and counterclockwise rotation of the functional occlusal plane. In the upper arch, the incisors moved lingually and retruded, while the molars moved distally and tipped distally. In the lower arch, the incisors proclined and protruded, whereas the molars mesialized and tipped mesially. Finally, there was a significant reduction in overbite and overjet, with an obvious improvement in molar relationship. Conclusions: It was concluded that the MARA appliance proved effective in correcting Angle’s Class II, division 1 malocclusion while inducing skeletal changes and particularly dental changes.Objetivo: avaliar os efeitos proporcionados pelo aparelho MARA no tratamento da má oclusão de Classe II, 1ª divisão. \ud Métodos: utilizou-se uma amostra de 44 jovens, divididos em dois grupos — Grupo MARA, com idade inicial média de \ud 11,99 anos e tratado com o aparelho MARA por um período médio de 1,11 ano; e Grupo Controle, com idade inicial média \ud de 11,63 ano e observado por um período médio de 1,18 ano, sem nenhum tratamento. Utilizou-se as telerradiografias em \ud norma lateral para comparar os grupos quanto às variáveis cefalométricas das fases inicial e final. Para essas comparações, \ud aplicou-se o teste t de Student. Resultados: o aparelho MARA proporcionou efeitos na restrição do crescimento maxilar, \ud sem nenhuma alteração do desenvolvimento mandibular, com melhora da relação maxilomandibular, aumento da altura \ud facial anteroinferior e inclinação anti-horária do plano oclusal funcional. Na arcada superior, os incisivos foram lingualizados \ud e retruídos, e os molares foram distalizados e inclinados para distal. Na arcada inferior, ocorreu vestibularização e protrusão \ud nos incisivos, e mesialização e inclinação mesial dos molares. Por fim, observou-se uma redução significativa nos trespasses \ud horizontal e vertical, e uma melhora evidente na relação molar. Conclusão: pode-se concluir que o aparelho MARA foi \ud eficaz na correção da má oclusão de Classe II, 1ª divisão, promovendo alterações esqueléticas e, principalmente, dentárias

Effects of intrusion combined with anterior retraction on apical root resorption

This study evaluated the influence of intrusion mechanics combined with anterior retraction on root resorption of the maxillary incisors. A sample of 56 patients was divided into two groups: group 1 comprised 28 patients (12 females and 16 males), presenting with an increased overjet and deep overbite (6.48 and 4.78 mm, respectively) treated with reverse curve of Spee intrusion mechanics and group 2 comprised 28 patients (12 females and 16 males) with an increased overjet of 5.67 mm and a normal overbite of 1.12 mm. The initial mean ages for groups 1 and 2 were 13.41 and 13.27 years, respectively. Pre- (T1) and post- (T2) treatment periapical radiographs were used to evaluate root resorption. The groups were compared using the Mann- Whitney U- test. Correlation between root resorption and tooth movement was investigated with Spearman's correlation coefficient. The subjects in group 1 had statistically greater root resorption (P < 0.05) than those in group 2. The initial overbite severity and the amount of correction had significant positive correlations with root resorption (r = 0.324 and r = 0.320, respectively). The combination of anterior retraction with intrusive mechanics causes more root resorption than anterior retraction of the maxillary incisors alone

Periodontal morphology of teeth moved into grafted alveolar cleft a CBCT assessment

Purpose: the purpose of this research was to assess the periodontal morphology of the canine mesialized to the grafted region in patients with unilateral alveolar clefts with by measuring images of cone- beam computed tomography (CBCT) exams. Methods: the sample comprised CBCT exams of 30 patients with unilateral cleft lip and/or palate during retention period after orthodontic comprehensive treatment. Buccal and lingual alveolar bone thickness of the canine in the clefted side (CF) were measured and compared to the canine (CsF) and lateral incisor in the non-cleft side (IL). To assess the buccal and lingual bone crest height, parassagital slices were obtained passing through the center of the crown of each evaluated teeth. It was calculated the distance form the cemento-enamel junction (CEJ) to the buccal and lingual alveolar bone crest. The comparison among the CF values with the CsF and IL was performed with the paired t test or the Wilcoxon test, depending on the distribution of normality. Results: the results showed that the buccal bone plate is thinner than the lingual bone plate in every tooth evaluated. When comparing the CF and the CsF, there was a statistically significant difference to the buccal alveolar bone thickness (p=0,002). When comparing the CF and IL, there was a statistically significant difference to the buccal alveolar bone thickness (p=0,001) and the lingual bone crest height (p=0,000). Conclusion: the mesialization of teeth to grafted alveolar bone in patients with clefts is a viable option under the periodontal and esthetical perception.FAPES

Influence of low-level laser on bone remodeling during induced tooth movement in rats

Objective: To analyze the effect of low-level laser on bone remodeling during induced tooth movement in rats. Materials and Methods: A diode laser (808 nm, 100 mW, 54 J on an area of 0.0028 cm2) was used. The application was continuous, punctual, and with contact. Forty-two 70-day-old Wistar rats had the maxillary left first molar moved using a force level of 25 g. In two experimental subgroups the movement was performed over 7 days and in three subgroups the movement occurred over 14 days. In the 7-day movement subgroups, one subgroup received laser irradiation on day 1 only; the other subgroup received laser irradiation on days 1, 3, and 5. In the 14-day movement subgroups, one subgroup received laser irradiation on day 1 only; the second on days 1, 3, and 5; and the third on days 1, 3, 5, 7, 9, 11, and 13. The control group was also divided into two subgroups, and movement occurred over two different periods of treatment (7 days and 14 days) without laser application; these were used as controls for the respective experimental subgroups. Inter-subgroup comparison was performed with Kruskal-Wallis, followed by Mann-Whitney and analysis of variance, followed by Tukey tests within the 7- and 14-day subgroups. Results: The subgroup with three laser applications showed significantly greater osteoclastic activity and bone resorption than the other subgroups in the 7-day movement subgroups. Conclusions: Low-level laser application significantly increased the osteoclastic but not the osteoblastic activity during the initial phases of tooth movement. In addition, the osteoclastic activity was dose-dependen

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

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

Influence of miniscrew dental root proximity on its degree of late stability

Purpose of this study was to evaluate the influence of miniscrew dental root proximity on its late stability degree. 40 miniscrews were inserted between maxillary second premolars and first molars for anterior retraction. Post-surgical radiographs were used to measure the septum width in the insertion site, insertion height, distal and mesial distance from miniscrew to dental root, and the smallest distance between miniscrew and dental root. The miniscrews were divided in two groups according to septum width: ?3 mm (20 miniscrews) and >3 mm (20 miniscrews). The soft tissue in the insertion site, sensitivity during load, plaque around the miniscrew, and evaluation period were also considered. The results showed no significant difference in miniscrew mobility degree and success rate between groups. Miniscrew dental root proximity did not influence the stability and success rate when the distance between the miniscrew and dental root indicated no periodontal ligament invasion. The overall success rate was 90% and no variable was associated with miniscrew failure. Nevertheless, patient sensitivity was frequently associated with some degree of mini-implant mobility. The septum width did not influence the stability and success rate of this anchorage system, but the extreme root proximity did.FAPESP # 2007/01862-

Dentoskeletal changes induced by the Jasper jumper and the activator-headgear combination appliances followed by fixed orthodontic treatment

Introduction: The aim of this study was to compare the dentoskeletal changes of patients with Class II Division 1 malocclusion treated with either the Jasper jumper appliance or the activator-headgear combination, both associated with fixed appliances. Methods: The sample comprised 72 subjects with Class II Division 1 malocclusion divided into 3 groups: group 1 included 25 subjects treated with fixed appliances and the force modules of the Jasper jumper at an initial mean age of 12.72 years, group 2 included 25 subjects treated with the activator-headgear combination followed by fixed appliances at an initial mean age of 11.07 years, and group 3 included 22 untreated subjects at an initial mean age of 12.67 years. Initial cephalometric characteristics and dentoskeletal changes were compared with analysis of variance. Results: Both experimental groups had similar dentoskeletal changes: restrictive effect on the maxilla, clockwise mandibular rotation and a slight increase in anterior face height, retrusion of the maxillary incisors, distalization of the maxillary molars, protrusion of the mandibular incisors, extrusion of the mandibular molars, and significant improvements of the maxillomandibular relationship, overjet, overbite, and the molar relationship. Conclusions: The effects of the Jasper jumper and the activator-headgear combination followed by fixed orthodontic appliances were similar in Class II malocclusion treatment

Intraoral distalizer effects with conventional and skeletal Anchorage: a meta-analysis

Introduction: The aims of this meta-analysis were to quantify and to compare the amounts of distalization and anchorage loss of conventional and skeletal anchorage methods in the correction of Class II malocclusion with intraoral distalizers. Methods: The literature was searched through 5 electronic databases, and inclusion criteria were applied. Articles that presented pretreatment and posttreatment cephalometric values were preferred. Quality assessments of the studies were performed. The averages and standard deviations of molar and premolar effects were extracted from the studies to perform a meta-analysis. Results: After applying the inclusion and exclusion criteria, 40 studies were included in the systematic review. After the quality analysis, 2 articles were classified as high quality, 27 as medium quality, and 11 as low quality. For the meta-analysis, 6 studies were included, and they showed average molar distalization amounts of 3.34 mm with conventional anchorage and 5.10 mm with skeletal anchorage. The meta-analysis of premolar movement showed estimates of combined effects of 2.30 mm (mesialization) in studies with conventional anchorage and 4.01 mm (distalization) in studies with skeletal anchorage. Conclusions: There was scientific evidence that both anchorage systems are effective for distalization; however, with skeletal anchorage, there was no anchorage loss when direct anchorage was used

Posttreatment and physiologic occlusal changes comparison

Objective: To compare posttreatment and postretention occlusal changes with the physiologic occlusal changes caused by natural development of untreated subjects. Materials and Methods: The sample was divided into three groups. Group 1 comprised 97 subjects treated with four premolar extractions at a mean pretreatment (T0) age of 13.03 years, a mean posttreatment (T1, first observation) age of 15.12 years, and a mean postretention (T2, second observation) age of 20.52 years. The mean observation period (T2-T1) was 5.39 years. Group 2 comprised 58 subjects treated nonextraction at a mean pretreatment age of 12.83 years, a mean posttreatment age of 14.99 years, a mean postretention age of 20.22 years, and a mean observation period of 5.22 years. Group 3 comprised 114 untreated subjects at a mean age at T1 of 14.91 years and at T2 of 20.48 years. The mean observation period was 5.56 years. Dental casts were evaluated using the Peer Assessment Rating (PAR) index and the Little irregularity index in maxillary and mandibular arches. Changes in PAR and Little indexes were compared among the three groups by analysis of variance and Tukey tests. Results: Intergroup comparison showed that at T1 and T2 the treated groups presented smaller PAR and Little indexes than the untreated group. In the observation period, the treated groups showed greater increase in PAR and Little maxillary indexes than the untreated group. The extraction group showed a greater increase of the Little mandibular index than the untreated group. Conclusions: The treated groups showed more changes according to PAR and Little maxillary indexes than the untreated group. The posttreatment change of the mandibular anterior crowding of the treated extraction group was greater than the mandibular crowding caused by physiologic changes in the untreated grou