Effective temporomandibular joint growth changes after stepwise and maximum advancement with Twin Block appliance

Angle class II correction: stepwise mandibular advancement or bite jumping? : A systematic review and meta-analysis of skeletal, dental and condylar effects

INTRODUCTION

There is no consensus regarding which mode of activation or mandibular advancement (stepwise [SW] or maximum bite-jumping [BJ]) of fixed or removable functional appliances (FFA; RFA) for correction of Angle class II malocclusion is advantageous to produce dental, skeletal or condylar effects and has the lowest rate of undesired dental or technical side-effects.

METHODS

A systematic search was conducted up to Oct. 20, 2019 in the MEDLINE, EMBASE, Scopus, Central Cochrane Library, and BBO databases. Included were preadolescent, adolescent, and adult humans with initial (pretreatment) Angle class II malocclusion, without further restriction. The intervention group was composed of subjects treated with FFA or RFA in SW mandibular advancement; the control group received BJ advancement. Search terms included prospective randomized and nonrandomized trials in English, German, Spanish, and Portuguese with the primary outcomes of skeletal and dental class II correction, effects on condylar growth, lower incisor proclination, overjet and overbite reduction. The risk of bias (ROB) was assessed using the Cochrane Collaboration's ROB2 tool. Mean differences were calculated and pooled by a meta-analysis using a random effects model.

RESULTS

Data from five randomized controlled trials (RCT) with 401 participants (mean age 13.84 years; SD 1.53) were included; 331 derived from four studies were included in the meta-analysis. The ROB in the selected articles was high. We detected a slightly increased reduction of the ANB (mean difference [MD] -0.95°, 95% confidence interval [CI] -1.80 to -0.10°; I² = 72%) that may be attributed to a slightly more pronounced increase of the SNB angle in SW-advanced mandibles (MD 0.27°; 95% CI -0.47 to 1.00°; I² = 38%). SW advancement tended to reduce the undesired side effect of lower incisor proclination (MD = -1.59°; 95% CI -3.98 to 0.8°; I² = 0%), indicating more pronounced mandibular incisor changes with bite-jumping advancement.

CONCLUSION

There is weak evidence indicating a slightly increased reduction of the ANB and less lower incisor proclination with SW advancement compared to BJ, but the clinical relevance is debatable due to the small overall magnitude and small number of high-quality papers.

REGISTRATION

Prospero #CRD42017075469 (www.crd.york.ac.uk/prospero).

Stepwise versus single-step mandibular advancement with functional appliance in treating class II patients : A meta-analysis

BACKGROUND

Difference in the functional orthopedic effect between stepwise mandibular advancement (SWA) and single-step mandibular advancement (SSA) in Angle class II patients remains unclarified.

OBJECTIVE

To compare the treatment effects of SWA and SSA on skeletal and dentoalveolar changes in class II patients.

METHODS

Randomized controlled trials (RCTs) and nonrandomized studies that compared differences in skeletal and dentoalveolar effects on class II patients between SWA and SSA were identified in PubMed, Embase, CENTRAL, and Web of Science. The grey literature was also searched. The primary outcomes were the mandibular length, L1-MP, and (ANB). Secondary outcomes included Pog sagittal, SNB, overjet, and mandibular plane angle.

RESULTS

Seven studies, including three RCTs and four cohort studies, were retrieved. Meta-analyses revealed pooled mean differences (95% confidence interval) of 0.79 mm (0.45 to 1.12 mm) for Pog sagittal, 0.53° (0.19 to 0.87°) for SNB, -0.51° (-0.83 to -0.20°) for ANB, -0.17° (-0.72 to 0.39°) for the mandibular plane angle, -0.41 mm (-0.90 to 0.09 mm) for overjet, -1.87° (-3.23 to -0.52°) for L1-MP, and 1.03 mm (0.63 to 1.42 mm) for the mandibular length. Publication bias was not observed, except for Pog sagittal. The quality of evidence for each outcome was judged as low (mandibular length, SNB and overjet) and very low (Pog sagittal, ANB, L1-MP and mandibular plane angle).

CONCLUSIONS

Although the magnitude of differences in clinical practice was limited, SWA might be more appropriate because it produces a greater skeletal change and less dental compensation than SSA. As the level of current evidence is low, more high-quality RCTs are needed.

Acrylic Planas Direct Tracks for Anterior Crossbite Correction in Primary Dentition

Anterior crossbite is one of the most common forms of malocclusion in sagittal relationship of maxilla and mandible. If not corrected at the earliest, it will cause restriction of normal growth and development of both the jaws. The incidence of anterior crossbite is 4 to 5% in primary dentition. Self-correction may occur at the transient dentition or permanent dentition stage, but treating it should be the first priority. Using either removable or fixed appliances is recommended for the correction, but it depends on the patient cooperation, treatment duration, and parent approval. In this case report, we have used planas direct tracks (PDTs) which helps the forward development of mandible and corrects the malocclusion. With two modifications to PDTs, one is using acrylic instead of composite. It is advantageous to both clinicians and parents by correcting the crossbite efficiently in short duration while taking less chair-side time for fabrication and being economical. How to cite this article: Devasya A, Ramagoni NK, Taranath M, Prasad KEV, Sarpangala M. Acrylic Planas Direct Tracks for Anterior Crossbite Correction in Primary Dentition. Int J Clin Pediatr Dent 2017;10(4):399-403.