Clinical effects of pre-adjusted edgewise orthodontic brackets: a systematic review and meta-analysis

Sifakakis

Keilig

et al. 2016

EORTHO

INTRODUCTION Torque of the maxillary incisors is essential in esthetics and proper occlusion, while torque expression is influenced by many factors. The aim of this finite element study was to assess the relative effect of tooth morphology, bracket prescription, and bracket positioning on tooth displacement and developed stresses/strains after torque application. METHODS A three-dimensional upper right central incisor with its periodontal ligament (PDL) and alveolus was modelled. The tooth varied in the crown-root angle (CRA) between 156°, 170°, and 184°. An 0.018-inch slot discovery® (Dentaurum, Ispringen, Germany) bracket with a rectangular 0.018 × 0.025-inch -titanium wire was modelled. Bracket torque prescription varied between 0°, 12°, and 22°, with bracket placement at the centre of the middle, gingival or incisal third of the crown. A total of 27 models were generated and a buccal root torque of 30°was applied. Afterwards, crown and apex displacement, strains in the PDL, and stresses in the bracket were calculated and analysed statistically. RESULTS The palatal crown displacement was significantly affected by bracket positioning (up to 94 per cent), while the buccal apex displacement was significantly affected by bracket prescription (up to 42 per cent) and bracket positioning (up to 23 per cent). Strains in the PDL were affected mainly by CRA (up to 54 per cent), followed by bracket positioning (up to 45 per cent). Finally, bracket prescription considerably affected the stresses in the bracket (up to 144 per cent). LIMITATIONS These in silico results need to be validated in vivo before they can be clinically extrapolated. CONCLUSION Tooth anatomy and the characteristics of the orthodontic appliance should be considered during torque application.

Section: Introductionmentioning

confidence: 99%

Torque differences according to tooth morphology and bracket placement: a finite element study

Sifakakis

Keilig

et al. 2016

EORTHO

“…As the outcome of fixed appliance therapy is bound to be affected by the bracket , the wire , and their interaction , a random‐effects model according to DerSimonian and Laird was deemed appropriate to incorporate this variability .…”

Section: Methodsmentioning

confidence: 99%

Lingual vs. labial fixed orthodontic appliances: systematic review and meta‐analysis of treatment effects

European J Oral Sciences

Gölz

Jäger

et al. 2016

The aim of this systematic review was to compare the therapeutic and adverse effects of lingual and labial orthodontic fixed appliances from clinical trials on human patients in an evidence-based manner. Randomized and prospective non-randomized clinical trials comparing lingual and labial appliances were included. Risk of bias within and across studies was assessed using the Cochrane tool and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Random-effects metaanalyses were conducted, followed by subgroup and sensitivity analyses. Six electronic databases were searched from inception to July 2015, without limitations. A total of 13 papers pertaining to 11 clinical trials were included with a total of 407 (34% male/66% female) patients. Compared with labial appliances, lingual appliances were associated with increased overall oral discomfort, increased speech impediment (measured using auditory analysis), worse speech performance assessed by laypersons, increased eating difficulty, and decreased intermolar width. On the other hand, lingual appliances were associated with increased intercanine width and significantly decreased anchorage loss of the maxillary first molar during space closure. Based on existing trials, there is insufficient evidence to make robust recommendations for lingual fixed orthodontic appliances regarding their therapeutic or adverse effects, as the quality of evidence was low. AbstractAim of this systematic review was to compare the therapeutic and adverse effects of lingual and labial orthodontic fixed appliances from clinical trials on human patients in an evidence-based manner.Randomized and prospective non-randomized clinical trials comparing lingual and labial appliances were included. Risk of bias within and across studies was assessed with the Cochrane tool and the GRADE approach. Random-effects meta-analyses were conducted, followed by subgroup and sensitivity analyses. Six electronic databases were searched from inception to July 2015 without limitations. A total of 13 papers pertaining to 11 clinical trials were included with a total of 407 (119 male / 228 female) patients. Lingual appliances were associated with increased overall oral discomfort compared to labial appliances, increased speech impediment (measured with auditory analysis), worse speech performance assessed by laypersons, increased eating difficulty, and decreased intermolar width. On the other side, lingual appliances were associated with increased intercanine width and significantly decreased anchorage loss of the maxillary first molar during space closure. Based on existing trials, there is insufficient evidence to make robust recommendations for lingual fixed orthodontic appliances regarding their therapeutic or adverse effects, as the quality of evidence was low.Registration: PROSPERO (CRD42015024596)

“…This can be achieved either by designing a new trial with an excessively large sample size (might not be costeffective) or by synthesizing many trials together in a metaanalysis. As an example, a meta-analysis of self-ligating versus conventionally-ligated brackets (Papageorgiou et al, 2014b) is replicated in Figure 3. For this metaanalysis, four RCTs were pooled in the comparison of overall treatment duration with either bracket system.…”

Section: Are Subgroup Analyses Credible?mentioning

confidence: 99%

“…Clinical judgement from the side of the orthodontist is needed to decide whether an effect is clinically relevant and this procedure might include a large degree of subjectivity. A useful rule Figure 3 Reconstruction of a forest plot of four trials comparing self-ligating with conventionally ligated brackets in terms of overall treatment duration (Papageorgiou et al, 2014b). All four trials are consistent (on the same side of the forest plot), but their 95% confidence intervals (horizontal lines) cross the vertical line of no-effect.…”

Section: Are Subgroup Analyses Credible?mentioning

confidence: 99%

Meta-analysis for orthodontists: Part II – Is all that glitters gold?

Journal of Orthodontics

2014

Systematic reviews with quantitative synthesis of included studies (meta-analysis) are being produced at increased rates in orthodontics. However, their reporting quality is often suboptimal, and methodological limitations can affect their conclusions. This article is designed to help orthodontists critically appraise the validity of a meta-analysis by providing 11 questions that address the planning, conduct and interpretation of these investigations.