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

Evaluation of long-term hard tissue relapse following surgical-orthodontic treatment in skeletal class II patients: A systematic review and meta-analysis

This systematic review and meta-analysis was performed to evaluate the long-term hard tissue stability and relapse factors following surgical-orthodontic treatment in skeletal class II patients. A literature search was conducted using Embase, Cochrane Central, Web of Science, and PubMed, yielding 3184 articles published up to January 2019. Risk of bias was assessed following the Cochrane handbook. Ten articles met the inclusion criteria. A total of 1079 patients were followed up for 5-13 years. The qualitative findings showed a variety of extrinsic and intrinsic factors affecting long-term stability. Meta-analysis for the amount and direction of cephalometric landmark displacement in the vertical and sagittal planes showed significant angular increases of ANB and backward relapse of SNB, however within the clinically acceptable range of 4°. In relation to linear measurements, the mean differences in all landmarks were within the clinically acceptable range of 2mm except for gonion. In conclusion, this systematic review showed multiple intrinsic and extrinsic factors responsible for relapse. However, the outcomes of the meta-analysis are limited due to the heterogeneity of data, small number of studies, and inconsistent methods of evaluation. Further high-quality studies utilising standardised three-dimensional methodologies are required to improve the level of evidence.

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.

Stability of Vertical, Horizontal and Angular Parameters Following Superior Repositioning of Maxilla by Le Fort I Osteotomy: A Cephalometric Study

INTRODUCTION

The restoration of normal jaw function, optimal facial aesthetics and long term stability are the goals of any orthognathic surgical procedures. During the last two decades, several cephalometric investigations have been reported on the skeletal changes following maxillary surgical procedures. The stability following LeFort I osteotomy and maxillary superior repositioning of the maxilla has not been studied extensively.

AIM

This study was aimed at determining the surgical changes brought about by superior repositioning of the maxilla by Le Fort I osteotomy and evaluate the stability of the surgical procedure one year following surgery.

MATERIALS AND METHODS

Presurgical and postsurgical and one year post surgical lateral cephalograms of 10 adult patients (age group - 17 to 40 years, with a mean age of 22.2 years) who had been treated successfully by maxillary Le-Fort I osteotomy and impaction were obtained. The lateral cephalograms were grouped into three categories: T1- Presurgical, T2- Postsurgical, T3- One year postsurgical. Comparisons were made between T1-T2 and T2-T3 to assess the changes following surgery and to evaluate the stability, one year following the surgery using 5 horizontal, 5 vertical linear and 2 angular measurement. Statistical analysis was done with SPSS (Version 17). Results were expressed as mean±standard deviation. A paired t-test was used to analyze the paired observations.

RESULTS

The difference between T1 and T2 values of vertical changes showed that they were statistically highly significant whereas from T2 to T3 they were insignificant. The difference between T1 and T2 values of all the horizontal changes showed that they were statistically significant whereas True Vertical Line (TVL) to point Anterior Nasal Spine (ANS) was not statistically significant. The horizontal changes from T2 to T3 were statistically not significant whereas TVL to point Incisal edge of upper incisor (Is) was statistically significant. The angular changes from T1 to T2, T2 to T3 were statistically not significant.

CONCLUSION

There was a significant reduction in the facial height and significant anterior movement of maxilla after surgery. Even after one year of surgery, negligible amount of relapse was recorded except at the incisors.

Botulinum Toxin for the Treatment of Excessive Gingival Display: A Systematic Review

BACKGROUND

To date, no standardized minimally invasive approach for the treatment of excessive gingival display exists.

OBJECTIVES

This systematic review aims to assess the evidence in the literature regarding the role of botulinum toxin injection in the management of gummy smile.

METHODS

All publications through December 2014 and pertaining to the subject were electronically searched in PubMed, Embase, Scopus, and Web of Science, and the bibliographies of retrieved articles were manually screened.

RESULTS

Out of 33 articles, 29 were discarded based on exclusion criteria. Although all 4 selected articles were in line with a role for botulinum toxin injection in the treatment of gummy smiles and the importance of targeting the levator labii superioris alaeque nasi muscle, studies differed in the type and the dose of toxin administered and the technique adopted.

CONCLUSIONS

Injection with botulinum toxin is a novel, safe, and cosmetically effective treatment for gummy smile when performed by experienced practitioners. However, further randomized controlled trials are warranted. LEVEL OF EVIDENCE 4: Therapeutic.

[Stability of the anterior teeth and hard tissue of skeletal class III malocclusion after orthodontic surgery: systematic review]

OBJECTIVE

This study aims to analyze the long-term stability of the anterior teeth and hard tissue of skeletal class III malocclusion after a three-year orthodontic surgery by systematic review.

METHODS

All studies about skeletal class III malocclusion with orthodontic-surgery were searched by computer-based retrieval and manual retrieval; the deadline is December 2013. The literature, filtered according to the inclusion criteria and exclusion criteria, was performed with quality. assessment. The same indicators of the anterior location and hard tissue stability were combined and evaluated with metaanalysis and descriptive analysis by Rev Man5.2.

RESULTS

Four before-and-after comparison study articles with 180 cases were included. The grades of the four literature evaluation were A. The meta-analysis results showed that comparing the three-year post-orthodontic-surgery and post-orthodontic-surgery, the total weighted mean difference (WMD) of Ul-SN was 4.29 (P<0.05); the WMD of Ll-MP, OB, OJ, SNA, SNB, ANB, and MP-SN were -1.58, 0, -0.41, -0.58, 0.25, -0.70, and 0.39, respectively (P>0.05). The measurement methods of A and B point position were different, hence the qualitative description were as follows: point A remained at a relatively stable position, and point B had some replacement compared with post-operative (P<0.05).

CONCLUSION

To the skeletal class III malocclusion after three-year orthodontic-surgery, the position of the lower anterior teeth could be kept stable, as well as the overbite and the overjet of the anterior teeth; only the upper inci- sor has a lip-inclined relapse. The maxillary could also be kept stable, and the mandibular had a little relapse.

[Stability of the anterior teeth and hard tissue of skeletal class III malocclusion after orthodontic surgery: systematic review]

OBJECTIVE

This study aims to analyze the long-term stability of the anterior teeth and hard tissue of skeletal class III malocclusion after a three-year orthodontic surgery by systematic review.

METHODS

All studies about skeletal class III malocclusion with orthodontic-surgery were searched by computer-based retrieval and manual retrieval; the deadline is December 2013. The literature, filtered according to the inclusion criteria and exclusion criteria, was performed with quality. assessment. The same indicators of the anterior location and hard tissue stability were combined and evaluated with metaanalysis and descriptive analysis by Rev Man5.2.

RESULTS

Four before-and-after comparison study articles with 180 cases were included. The grades of the four literature evaluation were A. The meta-analysis results showed that comparing the three-year post-orthodontic-surgery and post-orthodontic-surgery, the total weighted mean difference (WMD) of Ul-SN was 4.29 (P<0.05); the WMD of Ll-MP, OB, OJ, SNA, SNB, ANB, and MP-SN were -1.58, 0, -0.41, -0.58, 0.25, -0.70, and 0.39, respectively (P>0.05). The measurement methods of A and B point position were different, hence the qualitative description were as follows: point A remained at a relatively stable position, and point B had some replacement compared with post-operative (P<0.05).

CONCLUSION

To the skeletal class III malocclusion after three-year orthodontic-surgery, the position of the lower anterior teeth could be kept stable, as well as the overbite and the overjet of the anterior teeth; only the upper inci- sor has a lip-inclined relapse. The maxillary could also be kept stable, and the mandibular had a little relapse.