Long-term stability of surgical-orthodontic open-bite correction

Orthodontic correction of acquired open bite with TMJ degeneration: A retrospective study of outcomes and stability

BACKGROUND/PURPOSE

Newly developed temporary anchorage devices (TADs) serve a strong orthodontic anchorage to intrude molars for correction of anterior open bite (AOB). We measured cephalometric changes in skeletal open bite patients which developed subsequently to temporomandibular joint disorders with bilateral point contacts at terminal molars.

METHODS

We retrospectively recruited 32 patients who had been treated their TMD before orthodontic correction (overbite: -3.14 ± 1.86 mm). Partial orthodontic appliances were used to intrude posterior teeth using TADs until positive OB obtained (T1). Full fixed appliances were then used to achieve proper overjet and overbite (T2). We collected lateral cephalograms before (T0), during (T1) and after (T2) treatment, and at follow-ups (T3). Using ANOVA, we analyzed the differences among these time points to determine treatment changes and stability of orthodontic results.

RESULTS

In this group predominantly comprising young adult women, orthodontic treatment with TADs significantly reduced upper posterior dental heights (T2-T0:-1.84 ± 0.66 mm) and facilitated the retraction and uprighting upper incisors (T2-T0: -9.92 ± 1.72°), to achieve appropriate OJ (T2-T0: -3.21 ± 0.49 mm) and OB (T2-T0: 4.10 ± 0.28 mm) with p < 0.05. Except upper posterior dental height, most of cephalometric changes including OJ, OB, and upper incisal axis remained significant at follow-ups with retention time of 3.7 ± 2.6 years. Only three out of 30 patients experienced small amount of open bite at T3.

CONCLUSION

Orthodontic correction of OJ remained relatively stable among 90 % of patients with TMJ degeneration by intrusion via TADs. This modern but conservative orthodontic approach can improve occlusal functions in skeletal open bites.

Complications and Associated Risk Factors for Bimaxillary Osteotomies: A 15-Year Single-center Retrospective Study

AIM

The aim of this study was to retrospectively investigate the risk factors and their association on bimaxillary osteotomies to be able to improve patient selection and bimaxillary osteotomy planning.

MATERIAL AND METHODS

Patients treated with a bimaxillary osteotomy were included in the study. The complications were collected retrospectively from the patient data records. The effects of certain predictor variables on complication rates were also studied.

RESULTS

Sixty-one patients (48.0%) suffered from peri- or postoperative complications, or both. Twenty-five various perioperative complications were reported on 25 patients (19.6%) and 63 postoperative complications on 46 patients (36.2%). Ten patients (7.8%) suffered from both perioperative and postoperative complications. The effect of various predictor variables (sex, age, general health, type of malocclusion, surgery planning, use of bone grafts, and type of maxillary or mandibular movement) on complications was investigated, but we could not find any single factor to affect significantly on complication rate.

CONCLUSION

Both perioperative and postoperative complications are common in bimaxillary surgery, which must be noted in patient preoperative information. However, life-threatening complications are rare. Patient profile, bone grafting, type of osteosynthesis, or segmentation of the maxilla do not seem to affect the complication risk.

Long-term dental stability after orthognathic surgery: a systematic review

BACKGROUND

Long-term dental stability is one of the main objectives following combined orthodontic and orthognathic surgical treatment. It is influenced by multiple factors such as surgical, patient-related, and orthodontic aspects. While recent reviews mainly focus on short-term dental changes (0.5-2 years), longer follow-up dental stability remains hardly reviewed.

OBJECTIVES

The aim of this study was to evaluate long-term stability of dental and dentolabial changes following combined orthodontic and orthognathic surgical treatment with a minimum follow-up period of 5 years.

SEARCH METHODS

A systematic search was conducted up to December 2019 using Pubmed, Embase, Web of Science, and Cochrane Central.

SELECTION CRITERIA

Randomized controlled trials (RCTs), prospective and retrospective cohort studies, and case series with a minimum of 10 patients, which reported long-term dental stability following combined orthodontic and orthognathic treatment, were included.

DATA COLLECTION AND ANALYSIS

Long-term changes were assessed for overjet, overbite, maxillary, and mandibular incisors' position and relationship of lip position to maxillary and mandibular incisors. Risk of bias was assessed according to the Cochrane Handbook.

RESULTS

Following the screening of 3178 articles, 11 studies were included (2 RCT, 9 retrospective) with a postoperative follow-up period ranging from 5 to 15 years. A decrease in overjet was observed for patients with skeletal class III malocclusion, whereas overjet increased in class II patients at long-term follow-up. Overbite increased in class II patients, whereas class III showed variable results. The lower incisor position was more stable vertically than horizontally; the latter showing more outcome variability. Dentolabial changes corresponded to the normal ageing process and results were not clinically significant after long-term follow-up.

CONCLUSION

Current evidence suggests variability of dental and dentolabial stability in both skeletal class II and III patients. Further prospective studies are required to develop guidelines for long-term follow-up assessment using computer tomography or cone-beam computed tomography imaging, before final conclusions can be drawn.

REGISTRATION

The protocol for this systematic review (CRD42020133844) was registered in the International Prospective Register of Systematic Reviews (PROSPERO).

Vertical stability of different orthognathic treatments for correcting skeletal anterior open bite: a systematic review and meta-analysis

BACKGROUND

Several orthognathic procedures have been applied to correct skeletal anterior open bites (SAOB). Which method is most stable has been debated and no consensus has been reached and there is no conclusive evidence for clinicians to use.

OBJECTIVE

To analyse whether maxillary, mandibular, or bimaxillary surgery provides a better stability.

MATERIALS AND METHODS

A systematic search was conducted up to December 2020 using PubMed, EMBASE, Medline, Scopus, Web of Science, Cochrane CENTRAL, and Google Scholar. We made direct comparisons among the controlled trials and also made indirect comparisons via subgroup analysis on the aspects of occlusional, skeletal, and dento-alveolar stability to assess the overall stability of each method.

RESULTS

Finally 16 cohort studies were identified. At the occlusional level, pooled change in overbite was 0.21 mm in maxillary surgery, 0.37 mm in bimaxillary surgery, and -0.32 mm in mandibular surgery. At the skeletal level, pooled sella-nasion-Point A angle (SNA) was -0.12 degrees in bimaxillary surgery, -0.37 degrees in maxillary surgery and -0.20 degrees in mandibular surgery. The sella-nasion to palatal plane angle (SNPP) relapsed to a statistically significant degree in all samples received single maxillary surgery. Relapse of the sella-nasion-Point B angle (SNB) was 0.47 degrees in mandibular setback, -1.8 degrees in mandibular advancement, and -0.48 degrees in maxillary surgery. The Sella-Nasion to mandibular plane angle (SNMP) relapsed more in procedures involving bilateral sagittal split osteotomy than in other procedures. As for dento-alveolar changes, intrusion of molars and extrusion of incisors took place in most patients.

CONCLUSIONS

Bimaxillary surgery produced the most beneficial post-operative increase in overbite, maxillary surgery led to a lesser but still positive overbite change, and mandibular surgery correlated with some extent of relapse. Skeletally, bimaxillary surgery was more stable than maxillary surgery at both SNA and SNPP; SNB was more stable in mandibular setback than advancement; and SNMP was unstable in both mandibular and bimaxillary surgeries versus maxillary surgery with comparable surgical changes. Dento-alveolar compensation helped maintain a positive overbite.

REGISTRATION NUMBER

CRD42020198088.

Bimaxillary surgery to correct high-angle class II malocclusion: does a simultaneous genioplasty affect long-term stability?

BACKGROUND AND OBJECTIVES

High-angle skeletal Class II malocclusion is one of the most challenging dentofacial deviations to treat and, in adults, a combination of orthodontic treatment and bimaxillary orthognathic surgery is often indicated. This study examines the rate of clinically significant relapse and whether a genioplasty affects the treatment outcome of high-angle Class II malocclusions.

MATERIAL AND METHODS

Cephalometric tracings of 36 consecutively treated high-angle Class II patients were evaluated from pre-surgery to 3 years post-surgery. All patients had undergone bimaxillary surgery (Le Fort I and BSSO), 13 of them had in addition a genioplasty.

RESULTS

The maxilla remained stable, whereas relapse (greater than or equal to 2 mm) of the mandibular advancement was seen in 40 per cent of the patients. Advancement greater than 10 mm increased the risk for horizontal relapse. The overjet was normalized and remained stable despite mandibular relapse. Half of the patients had an anterior open bite 3 years post-surgery. A supplemental genioplasty did not affect the relapse rate.

CONCLUSIONS AND IMPLICATIONS

Overjet was normalized and remained stable long term; there was an open bite in half of the patients. Combined orthodontic and bimaxillary surgical treatment of high-angle Class II patients showed skeletal relapse (greater than or equal to 2 mm) of the mandible in 40 per cent of patients. Mandibular advancement greater than 10 mm increased the risk for relapse. There was no increased risk for dental or skeletal instability associated with a genioplasty in combination with maxillary and mandibular surgery in the treatment of high-angle skeletal Class II malocclusion.

Comparison of Postoperative Stability Between BSSRO and Le Fort 1 Osteotomy with BSSRO in Skeletal Class III Malocclusion with Severe Open Bite

Introduction

We aimed to investigate postoperative stability after orthognathic surgery in patients with skeletal class III malocclusion with severe open bite by comparison between bilateral sagittal splitting osteotomy (BSSRO) and BSSRO with Le Fort 1 osteotomy.

Materials and methods

Seventeen patients with skeletal class III malocclusion with severe open bite who were needed more than 6 degree counterclockwise rotation of distal segment by only BSSRO in preoperative cephalometric prediction. The subjects were divided into group A, where 9 patients were treated by BSSRO, and group B, where 8 patients were treated by BSSRO with Le Fort 1 osteotomy. Patient's characteristics of age, gender, preoperative over jet (OJ) and over bite (OB) were not found to be significantly different between the two groups. Counterclockwise rotation of distal segment in preoperative cephalometric prediction by only BSSRO was not found to be significantly different between group A of 7.6 (6-10.6) degree and group B of 9 (6-13) degree. The amount of rotation was reduced to 5.4 (3-10) degree by bimaxillary surgery using BSSRO and Le Fort 1 osteotomy in group B. OJ and OB were measured as occlusal stability factor. Distance between ANS-to-PNS plane and the edge of upper incisor (NF-U1Ed), and distance between Menton and edge of lower incisor (Me-L1Ed) were measured as skeletal stability factor using cephalometric analysis. These lengths were measured at pre-surgery (T0), 2 weeks after surgery (T1) and 1 year after surgery (T2), and these differences between the two groups were statistically analyzed.

Results

OJ and OB kept a good relation at any experimental periods. The change of Me-L1Ed was significantly larger in group A (1.21 mm at T0-T1, 1.02 mm at T0-T2) than in group B (0.14 mm at T0-T1, 0.16 mm at T0-T2). The change of NF-U1Ed was not significantly different between group A (1.07 mm at T0-T1, 0.57 mm at T0-T2) and group B (0.51 mm at T0-T1, - 0.05 mm at T0-T2).

Conclusion

In case with more than 6 degree counterclockwise rotation of distal segment, skeletal stability was better after bimaxillary surgery than only BSSRO; however, OJ and OB kept a good relation.

Anterior open bite correction with 2-jaw orthognathic surgery

A 26-year-old man with an anterior open bite was treated with orthodontics combined with 2-jaw surgery. Total treatment time was 19 months. Both his occlusion and facial appearance were significantly improved by the surgical-orthodontic treatment.

Nonsurgical correction of a severe anterior open bite with mandibular molar intrusion using mini-implants and the multiloop edgewise archwire technique

This article reports the case of a 24-year-old man with a large anterior open bite, mild mandibular crowding, increased overjet, no passive lip sealing, and Angle Class I malocclusion. The treatment results were achieved by mandibular molar intrusion using 1.8 × 8.5-mm mini-implants (C-implants) inserted between the mandibular first and second molars bilaterally. A 2.5-mm molar intrusion and open-bite closure occurred within 8 months. The multiloop edgewise archwire technique helped to intrude the posterior teeth. Total treatment time was 20 months. Fifty months postretention records are also presented. The patient achieved a suitable occlusion and satisfactory facial esthetics at the end of treatment and at the 50-month retention check.

Nonsurgical treatment and stability of an adult with a severe anterior open-bite malocclusion

OBJECTIVES

A skeletal anterior open-bite is a challenging malocclusion for the orthodontist due to the difficulty and instability of correction. Treatment options for the adult patient include extractions, anterior extrusion with intermaxillary elastics, posterior intrusion using skeletal anchorage, occlusal adjustment, and orthognathic surgery. Patient compliance plays a key role in posttreatment stability. The present case report demonstrates the orthodontic treatment of an adult patient who presented with a complex open-bite malocclusion.

MATERIALS AND METHODS

Treatment involved the placement of four miniscrews to assist intrusion of maxillary molars by applying posterior vertical maxillary elastics and extrusion of the anterior segments using anterior vertical interarch elastics.

RESULTS

Ideal intercuspation was successfully achieved and good stability was maintained during 3 years following treatment.

CONCLUSION

The intrusion of the maxillary molars with miniscrews is an interesting option in selected cases of skeletal anterior open bite. The retention protocol should be specific in these cases.

Surgical treatment of class II dento-facial deformity during adolescence: Long-term follow-up

PURPOSE

The purpose of this study is to evaluate the long-term stability of patients operated during adolescence on the base of clinical measurements and cephalometric analysis. Although, the potential benefits of early orthognathic surgery are known to be a reduction in treatment times and a greater healing potential leading to a better adaptation and stability of the occlusion, muscles, bones and joints, no consensus can be found in literature on the minimum age for surgical correction.

MATERIALS AND METHODS

In this study, thirty patients (age ≤ 15) with a class II dento-skeletal malocclusion were selected, of which 11 having a hyperdivergent (II,1) and 19 a hypodivergent (II,2) growth pattern, representing 2 distinct groups with a different treatment plan and long-term behavior.

RESULTS AND CONCLUSION

Observing the performance of all parameters over-time, it is seen that subjects belonging to division II,2 have a modification of the growth vectors maintaining the harmonious development between the jaws and the facial aesthetics. Less predictable is the trend in hyperdivergent patients, which are more prone to relapse in the long-term. Early surgery in these patients should be considered in the light of the degree of deformity and its influence felt by the patient on his development of self-image and interpersonal relationship.

Nonsurgical approach to Class I open-bite malocclusion with extrusion mechanics: a 3-year retention case report

Anterior open bite is one of the most challenging malocclusions for orthodontic treatment. The high incidence of relapse is a major concern. Therefore, accurate initial examination, diagnosis, treatment plan, and consideration of habitual risk factors are crucial for a successful outcome without unwanted sequelae. Excellent patient compliance for retainer wear is also a critical factor. This case report shows the 3-year stability of a nonsurgical and nonextraction orthodontic treatment of a 5-mm anterior open-bite malocclusion in a 12-year-old girl with extrusion mechanics and habit modification. After 2 years of orthodontic treatment, excellent outcomes were achieved. With an appropriate retention protocol, the long-term stability of the treatment was favorable.

Orthodontic treatment of severe anterior open bite and alveolar bone defect complicated by an ankylosed maxillary central incisor: a case report

Incisor trauma is common in children, and can cause severe complications during adolescent growth and development. This report describes the treatment of a 16-year-old patient with severe anterior open bite due to ankylosis of the maxillary left incisor after dental trauma as an 8-year-old. No examination or active treatment was undertaken until he was 16 years old. Clinical examination revealed that the maxillary left incisor was severely intruded accompanied by a vertical alveolar bone defect. Orthodontic treatment combined with surgical luxation took 3 years and 7 months. During treatment, the intruded incisor was moved to the occlusal level and the alveolar bone defect was restored, achieving normal occlusion. After two years of retention, the maxillary left incisor was retained in a stable normal position with a slightly reduced overbite. This case demonstrates that surgical luxation with orthodontic traction can be an effective approach, especially when the ankylosed tooth has a single root. Long-term monitoring of orthodontic stability and the maintenance of periodontal health are crucial in the post-treatment period.

Stability of the anterior maxillary segment and teeth after segmental le fort I osteotomy and postoperative skeletal elastic fixation with or without occlusal splint

OBJECTIVES

To assess the short term dental and skeletal stability of the anterior maxillary segment after segmental Le Fort I osteotomy with postoperative skeletal elastic fixation with or without occlusal splint.

MATERIAL AND METHODS

29 consecutive patients underwent segmental Le Fort I osteotomy and elastic skeletal fixation was applied. Patients were divided into two groups according to whether a fixed occlusal splint was used for six weeks (group A) or dismounted perioperatively (group B). Changes in landmarks and reference planes between the two timepoints were estimated on lateral cephalometric radiographs.

RESULTS

GROUP A

The upper incisor had a mean intrusion of -0.56 mm (SD 0.77; range -2.04 to 1.08 mm) and a mean posterior movement of -0.93 mm (SD 1.03; range -2.52 to 0.96 mm). The mean change in the axial inclination of the upper incisor was -0.33° (SD 2.56; range -6° to 4°) (95% CI: -1.75 to 1.08°). Group B: The upper incisor had a mean intrusion of -0.13 mm (SD 1.36; range -1.92 to 3.6 mm) and a mean anterior movement of 0.11 mm (SD 1.78; range -2.88 to 3.84 mm). The mean change in the axial inclination of the upper incisor was -0.07° (SD 3.05; range -5° to 5°) (95% CI: -1.83 to 1.69°). There was no statistically significant difference in stability between the two groups at the P value 0.05.

CONCLUSIONS

The skeletal anterior fixation with postoperative elastics for eight weeks may not compromise the early postoperative dental and skeletal stability of the anterior segment in segmental Le Fort I osteotomy.

Closure of anterior open bites with mandibular surgery: advantages and disadvantages of this approach

INTRODUCTION

While closure of an anterior open bite with a mandibular procedure may predispose a surgical case to instability, there are instances where this type of treatment planning is indicated.

METHODS AND MATERIALS

In this paper, the authors review the advantages and disadvantages of this approach and present three cases with varying degrees of success. Additionally, treatment strategies are presented for managing large advancements of the maxilla and mandible.

RESULTS AND SUMMARY

Counterclockwise rotation of the mandible is a valuable tool that can be used in the treatment of patients with dentofacial deformities.

Long-term stability of surgical-orthodontic correction of class III malocclusions with long-face syndrome

Objectives: In the first place, to evaluate skeletal changes of the maxilla and mandible induced by surgical-orthodontic correction of malocclusions class III with long-face syndrome and secondly, to analyze the stability of these skeletal changes in the long term (more than 6 years). Design of Study: A retrospective, unicentric and longitudinal study of 19 patients who had undergone surgical and orthodontic therapy for class III skeletal malocclusion with long-face syndrome was undertaken. A cephalometric analysis based on 8 angle measurements, and statistical analyses at three different points in time (before orthodontic treatment, after orthognathic surgery and after a retention period of at least 6 years) were carried out. Results: The changes produced following surgery show that, with the exception of the maxillary plane and the facial axis, all other variables presented changes of great statistical difference. Conclusions: Skeletal changes after orthodontic-surgical correction present maxillary advance, mandibular regression and mandibular anterorotation. The angles that represent the mandibular vertical position (ramus angle, goniac angle and mandibular plane angle) showed statistically significant relapses and no stability in contrast to the facial axis.

Key words:Long term results, stability, relapse, orthognathic surgery, class III, long face.