Nonextraction anterior open bite treatment with distalization and intrusion

This case report describes successful orthodontic retreatment for vertical control with nonextraction orthodontic therapy. A 31-year-old woman complained of anterior open bite and crowding. She had slightly protrusive lips but wanted to correct her malocclusion without extraction. Two palatal temporary skeletal anchorage devices were used for the distalization of the maxillary arch along with posterior intrusion. Mandibular distalization was performed with Class III elastics. The duration of active treatment was 22 months. The plain and efficient mechanics used contributed to the effective distalization of both arches, the intrusion of the maxillary posterior teeth, and favorable profile changes. The results were still stable at the five-year follow-up period.

Effects of orthodontic camouflage treatment vs orthodontic-orthognathic surgical treatment on condylar stability in Class II hyperdivergent patients with severe temporomandibular joint osteoarthrosis: a retrospective observational study

OBJECTIVES

To investigate the differences in profile changes and stability of the condyles between orthodontic camouflage treatment assisted by vertical control and that accomplished via orthognathic surgery in Class II hyperdivergent patients with TMJ osteoarthrosis (TMJOA).

MATERIALS AND METHODS

This study included 27 Class II hyperdivergent TMJOA patients (54 condyles) who received orthodontic camouflage treatment (13 patients) or orthognathic surgery (14 patients) Cone-beam computerized tomography (CBCT) scans were taken before treatment (T1) and 1 year after treatment (T2). Cephalometric and TMJ measurement analyses were conducted to evaluate the change in profile and condyles from T1 to T2 using independent samples t-test and paired t-test. Three-dimensional (3D) deviation analysis was also performed to evaluate the stability of condyles from T1 to T2.

RESULTS

Both groups showed significant profile improvement from T1 to T2. The changes in Z angle and ANB angle were larger in the surgical group than in the orthodontic group. Condylar width, length, and height remained stable after treatment in the orthodontic group (P > .05), while they reduced by 0.67 ± 0.85 mm, 1.14 ± 1.10 mm, and 1.07 ± 1.34 mm, respectively, in the surgical group (P < .05). Superior, posterior, medial, and lateral joint spaces were significantly reduced in the orthodontic group (P < .05). 3D deviations intuitively showed that condylar bone in the orthodontic group was more stable than that in the surgical group.

CONCLUSIONS

For Class II hyperdivergent patients with severe TMJOA, orthodontic camouflage treatment with vertical control can effectively maintain the stability of condyles while significantly improving the profile. Surgical treatment yields a better profile but may increase the risk of condyle resorption.

Effectiveness of micro-implant in vertical control during orthodontic extraction treatment in class II adults and adolescents after pubertal growth peak: a systematic review and meta-analysis

OBJECTIVE

To compare the effectiveness of micro-implant (MI) and conventional anchorage (CA) in vertical control during orthodontic extraction treatment of class II adults and adolescents after pubertal growth peak.

MATERIALS AND METHODS

Literature search was conducted through Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, EMBASE, Web of Science, China National Knowledge Infrastructure (CNKI), Wanfang Database, VIP, China Biology Medicine (CBM), and other sources, from inception to December 2021. Randomized clinical trials (RCTs) and controlled clinical trials (CCTs) were included. Mean differences (MDs) with 95% confidence intervals (CIs) were conducted. A meta-analysis concerning change of mandibular plane, vertical change of upper and lower molar, change of occlusal plane, SNB, chin position, and profile was carried out.

RESULTS

A total of 10,669 records were identified in the database search, and 19 studies (10 RCTs and 9 CCTs) were included in the final analysis. Compared with CA, MI significantly decreased mandibular plane angle and intruded upper molars. No significant difference was found in vertical change of lower molars, occlusal plane, SNB, chin position, and profile.

CONCLUSION

MI seems to be more effective than CA in vertical control during orthodontic extraction treatment of class II adults and adolescents after pubertal growth peak.

CLINICAL RELEVANCE

MI should be given priority when considering the vertical control of class II patients, which is beneficial to the counterclockwise rotation of mandible or at least prevention of deterioration of the profile.

The effect of orthodontic vertical control on the changes in the upper airway size and tongue and hyoid position in adult patients with hyperdivergent skeletal class II

BACKGROUND

At present, there are still controversies about the influence of orthodontic treatment on the size of upper airway and the position of hyoid bone. We investigated the effect of orthodontic vertical control therapy on the size of the upper airway and position of the tongue and hyoid bone in adult patients with hyperdivergent skeletal Class II.

METHODS

Overall, 15 adults with hyperdivergent skeletal Class II and normal occlusion, respectively, were selected as the experimental and control groups. The angle and line of the craniofacial structure, upper airway, hyoid bone position and three-dimensional (3D) upper airway indexes were measured using the Uceph 4.2.1 standard version and Mimics 21.0 software, respectively. The paired t-test, Wilcoxon symbol rank test, t-test of two independent samples, two independent sample nonparametric tests, Mann-Whitney U test, Pearson correlation analysis, the Univariate linear regression analysis and Multiple linear regression analysis were performed.

RESULTS

After treatment, the S-Go/N-Me (%) and the MP-SN and XiPm-SN angles were significantly different (P < 0.01). The U-MPW and PAS significantly increased (P < 0.05), sagittal diameter L₂ increased significantly, and transverse diameter L₂ decreased significantly (P < 0.01). Although no significant correlation was observed between the vertical change in the jaw and that in U-MPW and PAS, the sagittal diameter L₂ showed a significant correlation (P < 0.05). The Multiple linear regression analysis showed that there was a significant negative correlation between the variables MP-SN and sagittal diameter L₂ and positive correlation between S-Go/N-Me(%) and H-MP (P < 0.05). Furthermore, significant differences between the Hv (P < 0.01) and sagittal diameter L₁(P < 0.05) were observed before and after treatment.

CONCLUSIONS

After the orthodontic vertical control therapy in patients with hyperdivergent skeletal Class II, the upper airway only underwent adaptive changes during treatment without substantial size changes, the position of tongue body and hyoid bone did not change significantly. Furthermore, compared with normal occlusion, the velopharyngeal segment airway of patients with hyperdivergent skeletal Class II remains narrow and long after treatment.

上磨牙颊侧微种植体支抗在安氏Ⅱ类正畸减数拔牙患者垂直向控制中的作用

OBJECTIVE

To investigate the efficacy of vertical control by using conventional mini-implant anchorage in maxillary posterior buccal area for Angle class Ⅱ extraction patients.

METHODS

Twenty-eight Angle class Ⅱ patients [9 males, 19 females, and age (22.6±2.8) years] were selected in this study. All of these patients were treated by using straight wire appliance with 4 premolars extraction and 2 mini-implant anchorage in maxillary posterior buccal area. In this study, the self-control method was used to measure and analyze the lateral radiographs taken before and after orthodontic treatment in each case, the main cephalometric analysis items were related to vertical changes. The digitized lateral radiographs were imported into Dolphin Imaging Software (version 11.5: Dolphin Imaging and Management Solutions, Chatsworth, California, USA), and marked points were traced. Each marked point was confirmed by two orthodontists. The same orthodontist performed measurement on the lateral radiographs over a period of time. All measurement items were required to be measured 3 times, and the average value was taken as the final measurement result.

RESULTS

Analysis of the cephalometric radiographs showed that, for vertical measurements after treatment, the differences of the following measurements were highly statistically significant (P < 0.001): SN-MP decreased by (1.40±1.45) degrees on average, FMA decreased by (1.58±1.32) degrees on average, the back-to-front height ratio (S-Go/N-Me) decreased by 1.42%±1.43% on average, Y-axis angle decreased by (1.03±0.99) degrees on average, face angle increases by (1.37±1.05) degree on average; The following measurements were statistically significant (P < 0.05): the average depression of the upper molars was (0.68±1.40) mm, and the average depression of the upper anterior teeth was (1.07±1.55) mm. The outcomes indicated that there was a certain degree of upper molar depression after the treatment, which produced a certain degree of counterclockwise rotation of the mandibular plane, resulting in a positive effect on the improvement of the profile.

CONCLUSION

The conventional micro-implant anchorage in maxillary posterior buccal area has a certain vertical control ability, and can give rise to a certain counterclockwise rotation of the mandible, which would improve the profile of Angle Class Ⅱ patients.

Effects of long-term use of the lower lingual arch from 8.5 years to 13.2 years

OBJECTIVES

To investigate the effects of long-term use of the lower lingual arch (LLA) on the sagittal and vertical positions of the permanent lower incisors and first molars.

MATERIALS AND METHODS

The sample consisted of 98 patients who were treated with an LLA (LLA group) and 39 patients who were treated without an LLA (no-LLA group). The positional changes of the lower incisors and first molars were analyzed after performing mandibular structural superimpositions on lateral cephalometric radiographs taken before treatment (T1) and at the end of LLA therapy (T2). The mean ages at T1 and T2 were 8.5 years and 13.2 years, respectively. Study casts were analyzed to quantify arch dimensional changes.

RESULTS

Mesial movement of the lower molar cusp was similar between the LLA and no-LLA groups, but the vertical position was slightly greater at T2 in the LLA group. In the LLA group, there was a molar tip-back effect, and the lower incisors were proclined 4.2° more than in the no-LLA group. Arch perimeter decreased 3.6 ± 2.6 mm without an LLA and 0.97 ± 3.7 mm with an LLA. Intercanine and intermolar widths both increased about 1 mm more with an LLA (P < .0001).

CONCLUSIONS

The LLA does not seem to restrict mesial movement and vertical eruption of the lower incisors and molars in the long term. The LLA effectively preserves the arch perimeter at the expense of a slight lower incisor proclination.

Ribbon-wise customized lingual appliance and orthodontic anchor screw for the treatment of skeletal high-angle maxillary protrusion without bowing effect

This case report demonstrates the treatment of a skeletal Class II high-angle adult patient with bimaxillary protrusion, angle Class I occlusion, and crowded anterior teeth. A ribbon-wise arch wire and a customized lingual appliance with anterior vertical slots were used to achieve proper torque control of the maxillary anterior teeth. An orthodontic anchor screw and a palatal bar were used for vertical control to avoid increasing the Frankfort-mandibular plane angle (FMA) by maxillary molar extrusion. Through the combined use of the ribbon-wise customized lingual appliance, palatal bar, and orthodontic anchor screw, vertical control and an excellent treatment result were achieved without the vertical and horizontal bowing effects peculiar to conventional lingual treatment.

Cephalometric comparison of adult anterior open bite treatment using clear aligners and fixed appliances

OBJECTIVES

To compare fixed appliances and clear aligner therapy in correcting anterior open bite and in controlling the vertical dimension in adult patients with hyperdivergent skeletal patterns.

MATERIALS AND METHODS

In this retrospective study, two treatment groups of adult (≥18 years old) hyperdivergent patients (mandibular plane angles of ≥38°) with anterior open bites were included: 17 fixed appliance patients and 36 clear aligner patients. Thirteen cephalometric measurements representing the vertical dimension were reported for each group. A two-sample t-test was used to assess differences in changes in mandibular plane angle and overbite between the two treatment groups.

RESULTS

There were no statistical differences found in the magnitude of overbite correction and the changes in any of the cephalometric measurements for vertical control. The clear aligner group showed a slightly greater amount of lower incisor extrusion ( P = .009). The main mechanism of open bite correction was similar between the two treatment groups and was accomplished through retroclination of the upper and lower incisors while maintaining the vertical position of the upper and lower molars.

CONCLUSIONS

Cephalometric comparison of anterior open bite correction and changes in the mandibular plane angle associated with use of clear aligners and fixed appliances did not demonstrate statistically significant differences in adult hyperdivergent patients.

Nonsurgical correction of a severe anterior deep overbite accompanied by a gummy smile and posterior scissor bite using a miniscrew-assisted straight-wire technique in an adult high-angle case

In the present report, we describe the successful use of miniscrews to achieve vertical control in combination with the conventional sliding MBT™ straight-wire technique for the treatment of a 26-year-old Chinese woman with a very high mandibular plane angle, deep overbite, retrognathic mandible with backward rotation, prognathic maxilla, and gummy smile. The patient exhibited skeletal Class II malocclusion. Orthodontic miniscrews were placed in the maxillary anterior and posterior segments to provide rigid anchorage and vertical control through intrusion of the incisors and molars. Intrusion and torque control of the maxillary incisors relieved the deep overbite and corrected the gummy smile, while intrusion of the maxillary molars aided in counterclockwise rotation of the mandibular plane, which consequently resulted in an improved facial profile. After 3.5 years of retention, we observed a stable, well-aligned dentition with ideal intercuspation and more harmonious facial contours. Thus, we were able to achieve a satisfactory occlusion, a significantly improved facial profile, and an attractive smile for this patient. The findings from this case suggest that nonsurgical correction using miniscrew anchorage is an effective approach for camouflage treatment of high-angle cases with skeletal Class II malocclusion.

Effectiveness of mini implants in three-dimensional control during retraction - a clinical study

INTRODUCTION

Three-dimensional control throughout the orthodontic treatment is essential for uncompromised results. Mini screws introduced for orthodontic anchorage has given the clinician an option of absolute three dimensional control. The purpose of this study was to compare and measure the vertical control and torque control of incisors and molar during enmass retraction with titanium microimplants and conventional molar anchorage.

MATERIAL AND METHODS

Twenty patients were selected with extraction of all first premolars and bonded with 0.022″ slot MBT system. After aligning and leveling, all subjects were placed with 0.019″ X 0.025″ posted SS wire with standardized torquing curve. The 20 subjects were randomly divided into 2 groups consisting of 10 each (Group A & Group B). Group A subjects, implants were placed and Group B formed the control group. Retraction was carried out using NiTi closed coil springs. The assessment of the vertical and torque control of incisors and tipping and vertical control of molars was done by radiographic method using lateral cephalogram taken before and after retraction.

RESULTS

The torque control of incisors, P11 value in group A and B indicated no significant difference. The molar tip, P12 value in group A indicated that there was distal tipping of molars while the P12 in group B indicated mesial tipping. On vertical plane P21, P22 and P23 values in Group A indicated that there was intrusion of incisors and molars while value in Group B indicated extrusion of incisors and molars.

CONCLUSION

Three dimensional control is better in the implant group compared to the non implant group. Therefore the implant group definitely has citied advantages over conventional method.