Changes consequent to maxillary molar distalization with the bone-anchored pendulum appliance

Retrospective comparison of two different miniscrew-supported molar distalization methods applied in the buccal and palatal regions

BACKGROUND

To compare dentofacial effects of distalization with miniscrew-supported pendulum and infrazygomatic crest miniscrews.

METHODS

The study included 36 patients whose lateral cephalometric radiographs were obtained before (T0) and after (T1) distalization. Patients were divided into two groups according to the treatment methods: 1) distalization with miniscrew-supported pendulum (MSP) (n = 19; 14 girls and 5 boys; mean age 16.9 ± 1.46 years) and 2) distalization with infrazygomatic crest (IZC) miniscrews (n = 17; 8 girls and 9 boys; mean age 17.0 ± 1.68 years). Dental, skeletal and soft tissue measurements were performed on lateral cephalograms taken from individuals.

RESULTS

A significant molar distalization was achieved both in the MSP group (3.52 ± 0.76 mm at 8.71 ± 2.02 months) and the IZC group (3.5 ± 0.74 mm at 9.7 ± 2.5 months) (P < 0.001 for both). Premolar distalization was significantly lower in the MSP group (1.73 ± 1.09 mm) than in the IZC group (2.81 ± 0.79 mm) (P < 0.01). Significant molar tipping was observed in both groups (P < 0.001), while no significant difference was found between the groups (P > 0.05). Retrusion of maxillary incisors were significantly higher in the IZC group (2.75 mm) than in the MSP group (0.98 mm) (P < 0.01). A significant difference was found between the two groups with regard to the changes in overjet and overbite (P < 0.05).

CONCLUSIONS

Both distalization methods were found to be effective in achieving a Class I molar relationship in patients with Class II malocclusion.

Effectiveness of miniscrew-supported maxillary molar distalization according to temporary anchorage device features and appliance design: systematic review and meta-analysis

OBJECTIVES

To evaluate the effectiveness of distalizing maxillary first molars (U6) by temporary anchorage devices (TADs) according to their location (palatal, buccal, and zygomatic), their number, and appliance design.

MATERIALS AND METHODS

An electronic search of maxillary molar distalization with TADs was done through April 2023. After study selection, data extraction, and risk-of-bias assessment, meta-analyses were performed for the extent of distalization, distal tipping, and vertical movement of U6 using the generic inverse variance and random-effects model. The significance level was set at 0.05.

RESULTS

Forty studies met the inclusion criteria: 4 randomized controlled trials (RCTs), 13 prospective studies, and 23 retrospective studies (total of 1182 patients). Distalization of the U6 was not significantly greater (P = .64) by palatal (3.74 mm) and zygomatic (3.68 mm) than by buccal (3.23 mm) TADs. Distal tipping was significantly higher (P < .001) in nonrigid (9.84°) than in rigid (1.97°) appliances. Vertical movement was mostly intrusive and higher but not significantly different (P = .28) in zygomatic anchorage (-1.16 mm).

CONCLUSIONS

Distalization of U6 with TADs can be an effective and stable treatment procedure, especially when performed with rigid palatal appliances. However, further RCTs or prospective cohort studies are strongly recommended to provide more clinical evidence.

Comparison of the Bone-Anchored Pendulum Appliance and the Bone-Anchored Intraoral Bodily Molar Distalizer: An Original Research

Introduction

With the advent of mini-implants, Class II correction has become routine. The study's goal was to compare the "Bone-Anchored Pendulum Appliance (BAPA)" to the "Bone-Anchored Intraoral Bodily Molar Distalizer (BAIBMD)" in terms of clinical efficacy.

Materials and Procedures

Five boys and five girls were among the 10 patients in this split-mouth trial who had to have their molars distalized. On one side, BAPA Construction, and on the other, BAIBMD was piloted. A titanium mini-screw was used to secure both appliances to the bone since this was a spilled-mouth technique. The first molar bands to apply 200 g of force were used for both devices, as with all the other components that were similar for both appliances. For both sides, the nature, duration, and rate of tooth movement were compared. Using the Wilcoxon signed-rank test, descriptive statistics for several parameters were examined.

Results

Distalization was accomplished on both sides with clinical success. The rate of distalization did not show any significant variation. Less time was needed for distalization with BAPA, as evidenced by the statistically substantial variances in treatment duration between the two groups. Molar tipping was noticed in BAPA, and it was statistically significant.

Conclusion

While the pace of distalization was equal for both appliances, BAIBMD required more time than BAPA but resulted in a distal tooth movement that was mostly translatory in nature.

Correction of an adult Class III malocclusion through regaining of orthodontic space and an implant restoration

This case report describes the interdisciplinary treatment of a 23-year-old female with Class III malocclusion and a missing maxillary left second premolar. Treatment alternatives were discussed, and the selected treatment plan was presented to illustrate a way to gain space for the premolar implant restoration and correct Class III relationship through maxillary molar retraction followed by maxillary total arch protraction with a palatal temporary skeletal anchorage device. Esthetic anterior alignment and functional occlusal rehabilitation was achieved, and facial balance was maintained at the end of treatment. CLINICAL SIGNIFICANCE: Implant restoration in conjunction with regaining orthodontic space by a team of multidisciplinary dental specialists presents an effective treatment solution to permanent tooth agenesis. Class III malocclusion can be treated with a combination of maxillary protraction and mandibular retraction using temporary skeletal anchorage devices. The versatility of modified palatal C-plates presents greater clinical application when related side effects are controlled with solid understanding of their biomechanics.

The effect of third molars on maxillary molar distalisation using a miniscrew-supported 3D® maxillary bimetric distalising arch

Objectives: The aim of the present study was to investigate the effect of third molars on the efficiency and biomechanics of a novel miniscrew-supported 3D® Maxillary Bimetric Distalising Arch (3D-MBDA).

Methods: Twenty-three patients, whose third molars were either extracted at the beginning of treatment (Group 1, n =11) or retained (Group 2, n =12), were included in the study. Lateral cephalometric films and dental casts, taken at the beginning (T0) and at the end of upper molar distalisation (T1), were analysed to study the differences between groups.

Results: Crown distalisation of the first molars was similar between the groups; however, root distalisation, both at the trifurcation and apex levels, intrusion at the mesiobuccal cusp tip, and the distalisation rate were significantly higher in Group 1. The resultant tipping of the first molars in both groups was mesially-directed, unlike the usual distal tipping. The second molars distalised more, displaced less vestibularly and rotated mesiobuccally in Group 1, whereas they demonstrated a significantly higher vestibular displacement and distobuccal rotation in Group 2. The mean distalisation time was significantly shorter in Group 1 when compared to Group 2. The miniscrew success rate was 95.5% for Group 1 and 91.7% for Group 2.

Conclusion: The miniscrew-supported 3D-MBDA was found to have greater effects on root distalisation and the final inclination of the molars. The third molars were associated with limited root movement, unfavourable displacement of the second molars, as well as a slower distalisation rate. Therefore, the extraction of third molars prior to distalisation is recommended, especially when the miniscrew-supported 3D-MBDA is the appliance choice.

The Application of Pendulum as a Space Regainer in Orthodontic Treatment

Background:

The process of distalization in orthodontic treatment is often very difficult. The most common method is the use of cervical headgear. However, due to poor patient compliance, it leads to poor treatment outcomes. Treatment alternatives that require minimal compliance include Jones jig, magnets, and pendulum.

Objective:

This study aimed to perform distalization of a maxillary molars on a bilateral Class II molar relationship patient with a crowded maxillary arch.

Case Report:

A 10-year-old female with a Class II molar relationship, bilateral posterior crossbite, and nonerupted upper canines was treated with a rapid palatal expander (RPE), pendulum appliance, and fixed appliance. The crowding in the maxillary arch and spacing in the mandibular arch were eliminated, and transverse discrepancies were corrected.

Conclusion:

Pendulum appliance is very effective in creating spaces for the eruption of canines and ectopic premolars. Pendulum appliances have been introduced for a long time and have proven successful for molar distalization and space regainer and require minimal patient cooperation. Like other distalization appliances, distal tipping of the molars and mesial movement of the premolars could be observed.

Clinical Evaluation of Bone-Anchored Intraoral Bodily Molar Distalizer

Introduction:

Correction of Class II has become a routine with the introduction of mini-implants.

Objective:

The objective of the study was to evaluate the clinical efficiency of bone-anchored intraoral bodily molar distalizer (BAIBMD) as compared to bone-anchored pendulum appliance (BAPA).

Materials and Methods:

This split-mouth study included 11 subjects (6 boys and 5 girls) who required molar distalization. BAPA constructed on one side and BAIBMD on the other side. Both the appliances were anchored to the bone, using a single 2 × 8 mm titanium mini-screw placed in the anterior para-median region of the mid-palatal suture with its head embedded into the Nance button during construction. The force delivery mechanism on both the sides consisted of 200 g-force application, using an activated 0.032˝ titanium molybdenum alloy (TMA)[A]:Author: Please provide expansion for “TMA.” springs fabricated with respective designs and inserted into the lingual sheaths of the first molar bands. The rate, duration, and nature of tooth movement for both the sides were compared. Descriptive statistics for various parameters were analyzed using Wilcoxon signed-rank test.

Results:

Clinically successful distalization was achieved on both sides. No statistical difference was found in the rate of distalization. Differences in the treatment duration between the two groups were statistically significant, with less duration taken for distalization with BAPA. Statistically significant molar tipping was observed in BAPA.

Conclusion:

While both the appliances provided a similar rate of distalization, BAIBMD took more duration than BAPA but produced a predominantly translatory type of distal tooth movement.

Distalization in Orthodontics: A Review and Case Series

Distalization is a conservative method that is utilized in orthodontics to gain space by moving posterior teeth distally. It may be combined with other space gaining strategies, such as expansion, or can be used alone. Many methods have been used for distalization. These methods differ significantly in their place, whether to be extraoral or intraoral, site of action in upper and/or lower arch, and cooperation needed by the patient if it is removable or fixed. This review illustrates some of the most commonly used methods for distalization with a brief presentation of three cases that incorporated successful distalization techniques.

Time of maxillary molar distalization with non-compliance intraoral distalizing appliances: a meta-analysis

BACKGROUND/OBJECTIVE

To assess the mean maxillary molar distalization time with non-compliance intraoral distalizing appliances.

SEARCH METHODS AND SELECTION CRITERIA

Database search included PubMed, Web of Science, Scopus, The Cochrane Library, Lilacs, and a partial grey literature through Google Scholar and OpenGrey. The search was performed until May 2017 and updated on February 2019, without limitations regarding publication year or language. Controlled clinical trials (randomized and non-randomized prospective studies) reporting duration of maxillary molar distalization of Class II patients treated with intraoral distalizers were included.

DATA COLLECTION AND ANALYSIS

For the trials' quality assessment, the Cochrane Risk of Bias tool and the Cochrane Collaboration's ROBINS-I tool were used for the randomized controlled trials and non-randomized prospective studies, respectively. Database research, risk of bias (RoB) assessment, and extraction of data were performed by two independent investigators, with inclusion of a third reviewer, if disagreements emerged. Data was combined through a random-effects meta-analysis. Subgroup analyses regarding side of force application, type of anchorage, amount of molar distalization, and sensitivity analysis comparing study designs were also performed. Quality of evidence was assessed using the GRADE and SORT approaches.

RESULTS

Nine studies were included in the qualitative analysis; however, a meta-analysis was performed with only four studies, due to the presence of high RoB in the other studies. The random-effects meta-analysis assumes that the mean distalization time with distalizers is 8.34 months (95% confidence interval: 6.10, 10.58). Another meta-analysis was performed to evaluate the relationship between distalization time and the type of anchorage (conventional or skeletal), resulting in no significant difference. Both meta-analyses presented low-quality evidence.

LIMITATIONS

The major limitation of this meta-analysis is the fact that distalization time can be affected by a great range of factors.

CONCLUSIONS AND IMPLICATIONS

Correction of a half-to-full cusp Class II molar relationship with intraoral distalizers can be achieved in 8.34 months, and this distalization time may not be affected by the kind of anchorage used.

REGISTRATION

The protocol for this systematic review was based on the Cochrane Handbook for Systematic Reviews of Interventions 5.1.0 and was registered at PROSPERO database (http://www.crd.york.ac.uk/PROSPERO/display_record.php?ID=CRD42017068737). This systematic review is reported according to the PRISMA statement.

Transverse stability of Class II malocclusion correction with the pendulum appliance

INTRODUCTION

This study aimed to evaluate the stability of transverse changes after Class II malocclusion correction with the pendulum fixed distalizer, followed by preadjusted edgewise fixed orthodontic appliances.

METHODS

This longitudinal study was conducted in the maxillary dental casts of 20 Class II malocclusion subjects (mean age, 12.5 years; 14 females and 6 males). Eighty 3-dimensional maxillary dental casts were analyzed; 20 at the beginning of treatment, 20 after distalization, 20 after edgewise appliance debonding, and 20 at 5 years posttreatment. Maxillary transverse distances between canines, first premolars, second premolars, first molars, and second molars were analyzed using Geomagic Studio 5 (3D Systems, Rock Hill, SC).

RESULTS

There were no significant changes in intercanine distance during and after treatment. There were significant interfirst and intersecond premolar distance increases during treatment. There were significant interfirst and intersecond molar distance increases during the distalization phase. However, there were significant decreases in these distances at the end of treatment. There were no significant long-term posttreatment changes.

CONCLUSIONS

The intercanine distance remains stable during and after treatment. The interfirst and intersecond premolar distances significantly increase during treatment and remain stable after treatment. The interfirst and intersecond molar distances increase during the distalization phase, decrease at the end of treatment, and remain stable after treatment.

Evaluation of the effects of the hybrid Pendulum in comparison with the conventional Pendulum appliance

OBJECTIVE

To evaluate the anchorage control and distalization of maxillary molars with the hybrid Pendulum appliance and to compare the results with a conventional Pendulum appliance.

MATERIALS AND METHODS

This study was carried out on the pre-(T0) and post-(T1) treatment lateral cephalograms and dental casts of 43 patients with Angle Class II molar relationships who were treated with conventional or hybrid Pendulum appliances. The hybrid Pendulum (HP) group consisted of 22 patients (14 females; eight males; mean age 14.3 ± 2.43 years) and treatment results were compared with a conventional Pendulum appliance (CP) group, which consisted of 21 patients (15 females; six males; mean age 14.6 ± 3.39 years). Intragroup comparisons were made with Wilcoxon test and intergroup comparisons were made with Mann-Whitney U-test (P < .05).

RESULTS

The mean distalization duration was 0.70 ± 0.25 years in the HP group and 0.83 ± 0.4 years in the CP group. Maxillary first molars showed significant distal movement and tipping of 4.25 mm and 9.09° in the HP group, and 3.21 mm and 9.86° in the CP group. Loss of anchorage at the first premolars was significantly smaller in the HP appliance group compared to CP group. The second premolars distalized spontaneously in the HP group while they mesialized significantly in the CP group. Proclination and protrusion of maxillary incisors were greater with the CP appliance compared to the HP appliance.

CONCLUSIONS

Maxillary molar distalization was achieved with both appliances. Mesialization of the anchorage unit was controlled successfully with the hybrid Pendulum; however, the conventional Pendulum appliance caused anchorage loss.

Maxillary molar distalization using conventional versus skeletal anchorage devices: A systematic review and meta-analysis

INTRODUCTION

The purpose of this study was to systematically review the evidence regarding conventional versus skeletal anchorage devices for molar distalization.

METHOD

An electronic search was conducted. Hand searching was done in the reference lists of included studies and some journals. Studies comparing conventional and skeletal anchorage for molar distalization in Angle class I or II malocclusions were assessed. Presence of periodontal disease, second or third molar extraction and application of tooth accelerating methods led to exclusion of studies. Generic-inverse variance approach was used for meta-analysis by use of the mean difference and random-effect model. Risk of bias was evaluated in included studies.

RESULTS

A total of 1996 articles were found; of which, 1991 were excluded. The mean amounts of molar distalization/tipping in skeletal anchorage and conventional anchorage groups were 5.35mm/8.44° and 4.25mm/8.31°, respectively, which were not significantly different. The mean amounts of premolar movement in skeletal anchorage and conventional anchorage groups were -0.96mm and +2.21mm, respectively, which was statistically significant (P=0.004). Duration of treatment in skeletal anchorage and conventional anchorage groups was 8.23 months and 7.95 months, respectively, which were significantly different (P=0.0001). Risk of bias was assessed to be high.

CONCLUSION

The conventional and skeletal anchorage devices were not significantly different in terms of the amount of molar distalization/tipping. However, the anchorage loss was lower in the skeletal anchorage group. The treatment time was shorter in the conventional anchorage group. More studies with proper design are required.