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

ABSTRACT

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.

INTRODUCTION

Distalization of the molars (maxillary) is occasionally necessary to create the space needed for Angle’s Class-II malocclusion rectification. Pendulum appliance is frequently the distalization appliance of choice due to its simplicity in production and affordability. With a pendulum appliance, it is challenging to achieve the right translatory kind of tooth movement during distalization.[1] Keles and Sayinsu developed the intraoral corporeal molar distalizer to address the pendulum appliance’s predominately tipping tooth movement.[2]

Loss of anchoring is a frequent problem during distalization, which is undesired. The use of mini-implants for orthodontic anchoring was described by Konomi Distalization appliances, which take advantage of the anchorage capability of mini-implants inserted in the palate and have been made possible by the development of skeletal anchorage. Konomi anchored using miniplate fixation screws.[3] The pendulum device has been described by many authors as helping in skeletal anchorage and has been concluded to be favorable for the molar distalization.[4-7] For molar distalization, Chung et al.[8] employed segmented wire mechanics with a mini-implant. The added benefit of minimizing anchorage loss in the anterior segment while bringing about a mostly translatory kind of tooth movement would be provided by the employment of skeletal anchoring in conjunction with an intraoral bodily molar distalizer.[8-10]

A similar design has not previously been discussed in the literature. BAIBMD is the term we gave to the mini-implant we included in the design. The goal of the current study was to assess the effectiveness of BAIBMD with that of the BAPA. The null hypothesis indicated that there is no dissimilarity between BAIBMD and BAPA’s effectiveness.

MATERIAL AND METHODS

Five boys and five girls made up the initial group of 10 participants in this split-mouth trial that needed molar distalization. Both the Institutional Research Board and the Institutional Ethical Committee authorized the study. Following the patient agreement, the participants were chosen from among the patients presenting to the Department of Orthodontics based

• Inclusion Requirements

• Bilateral Class II molar relation of Angle (greater than 3 mm);

• Patients between the ages of 13 and 16 who are either male or female who have partially or fully erupted second molars on an OPG;

• An average or horizontal growth pattern

• Proper oral hygiene; and

• Not had any orthodontic treatment history.

• Exclusion Standards

The following criteria led to study exclusion:

• unwilling patients;

• patients with compromised health;

• vertical trend of growth.

The procedure was explained to each patient and their parents, and their signed consent was obtained. All of the subjects had their cephalograms, study models, and profile, and intraoral photos taken. Skeletal anchoring was achieved using a titanium mini-screw “2 x 8 mm, SK Surgicals, Pune, India”. The creation of the distalization springs involved the usage of “0.032′′ Titanium-Molybdenum alloy wire from Ormco in Orange, California”. A mini-screw was inserted in the anterior paramedian area of the mid-palatal suture, which is 3 to 4 mm lateral to the median line and 7 to 8 mm posterior to the incisive foramen.

Alginate impressions and stone castings were made while the mini-implant was in place. For the study, specially made 0.016′′ SS wire markers were employed. These were kept in place by acrylic caps that were designed for maxillary posterior teeth. They were positioned vertically. A lateral cephalogram was later imaged. These indicators let dentists evaluate the degree of molar distalization and the quantity of premolar and molar tilting movement on a cephalogram. Care was taken to prevent the superimposition of the two appliances in a single subject. These acrylic caps were taken off the teeth after the cephalogram was taken and preserved for use in the same procedure again following distalization. On the maxillary first molars, lingual bands with welded sheaths were cemented. When the appliances & mini-implant were in place, an alternate impression was created. Casts in stone were acquired.

The corporeal molar distalizer distalization spring was built on the left, whereas the pendulum appliance distalization spring was built on the right. The device was placed on the palate, and clinically, adaption was assessed. Composite was used to connect the Nance button to the implant head. The lingual sheaths on the first molar bands were put into the distalization springs after they were activated parallel to the median palatal suture to provide 200 g of force.

All of the patients received oral hygiene advice. Every four weeks, subjects were followed-up. During these visits, force levels were regularly checked, and the springs were reactivated as needed. Failure of the mini-screw was not observed in any of the patients. Once the distalization was achieved the spring was disabled. The Nance palatal arch was used to stabilize the distalization and provide reinforcement for the anchoring during later mechanotherapy.

Analysis

Cephalograms from before and after distalization were examined and contrasted. For cephalometric characteristics, the wire marker’s orientation is referred to as its “Long axis,” and its apex at the occlusal surface is referred to as its “cusp tip.” Cephalograms from before and after distalization were measured.

The evaluated linear parameters were:

1. The “Sella-Nasion plane’s horizontal reference line (HR)”

2. The “Sella point-based Vertical Reference Line (VR)”, which is parallel to the SN plane.

   • apex of the VR to I molar cusp;
   • The cusp point of the VR to II premolars and
   • Premolar cusp tip VR to I

The angles that were evaluated were: “ HR to I Molar Long Axis; HR to the II Premolar’s Long Axis; HR to I Premolar Long Axis”

RESULTS

The various cephalometric readings are given in Table 1. The first molar tipping for the BAIBMD was lesser than BAPA, while linear was greater for the BAPA than BAIBMD. The tipping was significantly different only for the first molar. For the premolars, both the tipping and linear are greater for the BAPA than BAIBMD. The rate of distalization was lower for the BAPA than for BAIBMD. The distalization time was greater for the BAPA than BAIBMD. This time was significantly greater between the groups [Table 1].

Table 1.

Various parameters observed in the study for the two appliances using the Wilcoxon Signed Rank

Cephalometric measure	BAIBMD Mean±SD	BAPA Mean±SD	P
I Molar Tipping*	5.3±2.1	9.1±2.8	0.005
I Molar Linear*	5.16±0.83	4.68±0.45	0.109
I Premolar Tipping	4.64±2.7	5.32±3.89	>0.99
I Premolar Linear	4.3±1.65	5±2.29	0.515
II Premolar Tipping	4.76±2.59	7.29±5.6	0.401
II Premolar Linear	4.13±1.9	4.9±2.13	0.721
Rate of distalization	1.7±0.31	1.5±0.28	0.959
Distalization time (months)	4.29±0.28	4.4±0.69	0.005

*Tipping (degrees); distalization (mm)

When the molar distalization was compared Wilcoxon Signed Rank for the two appliances there was no significant variance between the groups. However, when the Wilcoxon Signed Rank was used to compare the time of distalization there was a significant variance between the two appliances. For both, the parameters were lesser for the BAPA than for the BAIBMD [Table 2].

Table 2.

Comparison of both appliances for the distalization time and linear values

	Mean±Std. Deviation	P
Molar Linear Values (mm)
BAPA	4.6800±0.4554	0.152
BAIBMD	5.1600±0.8334
Distalization time (months)
BAPA	4.0230±0.1000	0.05
BAIBMD	4.2980±0.28020

DISCUSSION

One way to treat Angle’s Class II malocclusion is by orthodontic therapy using maxillary molar distalization. The devices selected for this study should be straightforward to construct and offer reliable distalization of the molar (maxillary) without compromising anchoring in the anterior portions. A straightforward device that is frequently used for distalization is the pendulum appliance, which Hilgers first introduced. The difficulty with pendulum appliances has been the significant unintended anchoring loss of the front teeth and minor tipping.[1] Undesirable round-tripping happens because the orthodontist must employ molars as anchorages to distalise adjacent areas after the desired amount of molar distalization has been accomplished. Keles and Sayinsu introduced an intraoral bodily molar distalizer. While this device assisted in regulating the various tooth movements necessary, the problem of unintended anchoring loss is still not resolved.[2]

Orthodontic mini-implants opened up new opportunities for achieving targeted tooth movements without worrying about losing anchorage. The prior device designs, which had to rely on the subjects’ cooperation, have been greatly simplified by the numerous applications that have been successfully deployed in a variety of orthodontic biomechanical settings.

In this study, the ideal palatal position was applied. BAPA was developed to combine the pendulum appliance with the benefit of skeleton anchoring.[4] The main goal of this research was to evaluate the possibility of using skeletal anchorages in conjunction with an intraoral body molar distalizer and to assess the effectiveness of this device. The newly created BAIBMD and BAPA were put side by side in this split-mouth trial to be compared.

The targeted class I molar relation was achieved in all the subjects for both appliances. Class, I molar relations required an average distalization time that was found to be greater for the BAIBMD group than for the BAPA group. The simultaneous uprighting and distal force mechanism provided by the bone-anchored distaliser’s spring may be to blame for the longer average distalization time. Similar average times were reported by other authors in their research for maxillary molar distalizations accomplished with a pendulum devices secured by a mini-implant.[4-6,9,10]

According to the current study, the BAPA group’s molars distalized 4.5 mm in four months. Both groups experienced distalization at a comparable rate. Regarding the rate of distalization, there was no statistically substantial alteration (P >.05). BAIBMD group had lesser distal tipping than BAPA; while having greater molar distalization than BAPA. With the Beneslider appliance, Wilmes and Drescher reported a mean mesial rotation that was contrary to the current study.[11]

In the current study, the BAPA group had more molar tilting than the BAIBMD group P =0.05. When employing the pendulum appliance, Joseph and Butchart found that the mean change in molar angulation was 15.7⁰.[12] Distal tipping at the maxillary molars was greater because the distalization force was created with 60 to 70 degrees posterior activation of the pendulum springs from the crown level and because there was no control mechanism associated with the tipping of the upper molars in the BAPA group. A physical molar distalizer device uprighting component was used to counteract this form of tipping. As a result, there was more molar tilting in the BAPA group. Our research also demonstrated that premolars spontaneously distalized. On the BAPA side, the first and second premolars moved distally similar to the BAIBMD side. On the BAPA side, the first and second premolars’ average distal angulations were greater than the BAIBMD. These results are in line with those of other research.[2,13,14] In earlier research it was claimed that the transeptal fibers were responsible for the premolars’ distal movement.[15-17] According to a study published in BAPA by Cambiano et al.,[18] the first maxillary molars’ distal movement of 3.5 mm and 11.2-degree tipping caused the Class II molar relationship to be corrected. The BAPA side in the current investigation displayed a distalization of 4.78 mm and distal tilting of 9.3 degrees.

Regarding the clinical application of the two methods, both appliances were easily made. It was simpler to insert the distalization spring in BAPA than the distalizer.

CONCLUSION

The distalization rates supplied by BAIBMD and BAPA were comparable, and the BAIBMD group took longer than BAPA. A chiefly translatory type of distal tooth movement was developed by BAIBMD. More distal toot movements of the tipping type were created by BAPA. Clinically successful distalization is provided by BAIBMD. By removing reactive stresses, the bodily molar distalizer’s design with skeletal anchorage facilitated avert adverse effects on anchoring anterior teeth.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.