The effectiveness of laceback ligatures during initial orthodontic alignment: a systematic review and meta-analysis

Lacebacks may be used to limit unwanted incisor proclination during initial orthodontic alignment; however, their use has not met with universal approval. This systematic review aims to appraise the evidence in relation to the effectiveness of lacebacks in controlling incisor position during initial alignment. Electronic database searches of published literature (MEDLINE via Ovid, Cochrane Central Register of Controlled Trials, LILACS, and IBECS) and unpublished literature were performed. Search terms used included randomized controlled trial, controlled clinical trial, random allocation, double blind method, orthodontics, and laceback. Data were extracted using custom forms. Risk of bias assessment was made using the Cochrane Collaboration risk of bias tool. The quality of the evidence was also assessed using GRADE. Mean differences in incisor inclination and antero-posterior changes in incisor and molar position during alignment were calculated. Two studies involving 97 participants were found to be at low risk of bias and were included in the quantitative synthesis. The random effects meta-analysis demonstrated that the use of lacebacks was associated with 0.5 mm greater posterior movement of the incisors during alignment; this finding was of limited clinical importance and statistically non-significant [95 per cent confidence interval (CI): -1.25, 0.25, P = 0.19]. Little difference (0.46 mm) was also found between laceback and non-laceback groups with regards to mesial molar movement (95 per cent CI: -0.33, 1.24, P = 0.26). According to the GRADE assessment, the overall quality of evidence relating to the use of lacebacks was high. There is no evidence to support the use of lacebacks for the control of the sagittal position of the incisors during initial orthodontic alignment.

Cochrane and non-Cochrane systematic reviews in leading orthodontic journals: a quality paradigm?

The aims of this study were to assess and compare the methodological quality of Cochrane and non-Cochrane systematic reviews (SRs) published in leading orthodontic journals and the Cochrane Database of Systematic Reviews (CDSR) using AMSTAR and to compare the prevalence of meta-analysis in both review types. A literature search was undertaken to identify SRs that consisted of hand-searching five major orthodontic journals [American Journal of Orthodontics and Dentofacial Orthopedics, Angle Orthodontist, European Journal of Orthodontics, Journal of Orthodontics and Orthodontics and Craniofacial Research (February 2002 to July 2011)] and the Cochrane Database of Systematic Reviews from January 2000 to July 2011. Methodological quality of the included reviews was gauged using the AMSTAR tool involving 11 key methodological criteria with a score of 0 or 1 given for each criterion. A cumulative grade was given for the paper overall (0-11); an overall score of 4 or less represented poor methodological quality, 5-8 was considered fair and 9 or greater was deemed to be good. In total, 109 SRs were identified in the five major journals and on the CDSR. Of these, 26 (23.9%) were in the CDSR. The mean overall AMSTAR score was 6.2 with 21.1% of reviews satisfying 9 or more of the 11 criteria; a similar prevalence of poor reviews (22%) was also noted. Multiple linear regression indicated that reviews published in the CDSR (P < 0.01); and involving meta-analysis (β = 0.50, 95% confidence interval 0.72, 2.07, P < 0.001) showed greater concordance with AMSTAR.

Subjective and objective perception of orthodontic treatment need: a systematic review

The aim of this work was to investigate the published evidence on the comparison of self-perception and diagnosis of orthodontic treatment need. A search of Cochrane Library, MEDLINE, Scopus databases, and archives of two orthodontic journals was carried out from January 1966 to August 2011 by the two authors using Medical Subject Heading terms. Studies that investigated solely either self-perception of orthodontic need by laypersons or assessment of orthodontic need by professionals were excluded from the data analysis. The methodological soundness of each study and the aggregate level of evidence were evaluated according to predetermined criteria. Moderate level of evidence, the relatively highest grade, was assigned to 9.1 per cent of the 22 studies, finally included in the data analysis. The overall evidence level provided by the evaluated publications was rated as limited. However, the existing body of evidence indicated a highly variable association between self-perception of orthodontic treatment need and orthodontist's assessment. Future controlled studies with well-defined samples and common assessment methodology will clarify further the relationship between perception of treatment need by laypersons and orthodontists and enhance international comparison and development of health care strategies.

Tooth eruption: altered gene expression in the dental follicle of patients with cleidocranial dysplasia

OBJECTIVES The dental follicle plays an important role in tooth eruption by providing key regulators of osteogenesis and bone resorption. Patients with cleidocranial dysplasia (CCD) exhibit delayed tooth eruption in combination with increased bone density in the maxilla and mandible, suggesting disturbances in bone remodeling. The aim of this study was to determine the expression of genes relevant for tooth eruption and bone remodeling in the dental follicles of patients with CCD and normal subjects. MATERIAL AND METHODS Thirteen dental follicles were isolated from five unrelated patients with CCD, and fourteen dental follicles were obtained from 10 healthy individuals. All teeth were in the intraosseous phase of eruption. The expression of RANK, RANKL, OPG, and CSF-1 was determined by quantitative RT-PCR. RESULTS In patients with CCD, the mRNA levels of RANK, OPG, and CSF-1 were significantly elevated compared with the control group. Accordingly, the ratios of RANKL/OPG and RANKL/RANK mRNAs were significantly decreased in patients with CCD. CONCLUSION The observed alterations in the expression and ratios of the aforementioned factors in the dental follicle of CCD individuals suggest a disturbed paracrine signaling for bone remodeling that could be responsible for the impaired tooth eruption seen in these patients.

A rat model for orthodontic translational expansive tooth movement

OBJECTIVES To present the development of an experimental model in rats for translational expansive tooth movement. SETTING AND SAMPLE Section of Periodontology at Department of Dentistry Aarhus University. Twenty male Wistar rats in two pilot experimental settings plus seven animals without any intervention serving as controls. MATERIAL AND METHODS The second molar (group P1) or the second and third molar (group P2) in the maxillae of the animals were moved buccally using transpalatal β-titanium springs. In the group P2, two spring types (high force and low force) and two preangulations (0° passive or 30° torsion moment) were tested. The amount and type of tooth movement achieved and the resulting skeletal effect were assessed on microCT images, histological analysis was performed on few selected specimens. RESULTS Expansive translational root movement amounting half a tooth width was achieved. Comparison of the amount of tooth movement at the right and left side of the maxilla showed that the expansion was rather symmetrical in the P2 group. Skeletal widening of the maxilla contributed in the P2 group to approximately one-third of the total root movement, whereas two-thirds were dental movement. CONCLUSION With the model used in the P2 group, further research on translational expansive tooth movement and its effect on the periodontium can be pursued. In models for orthodontic expansion, it is strongly recommended to separately evaluate skeletal and dental effects.

Facial esthetics in children with unilateral cleft lip and palate 3 years after alveolar bonegrafting combined with rhinoplasty between 2 and 4 years of age

OBJECTIVES To evaluate facial esthetics in patients with unilateral cleft lip and palate (UCLP) after alveolar bone grafting combined with rhinoplasty between 2 and 4 years of age. DESIGN Retrospective case-control study. SETTING The Department of Pediatric Surgery, Institute of Mother and Child, Warsaw, Poland. MATERIAL AND METHODS Photographs of full faces and cropped images of five nasolabial components: nasal deviation, nasal form, nasal profile, vermillion border, and inferior view were assessed by 5 professional and 14 layraters in 29 children (23 boys and 6 girls; mean age = 5.3 years, SD 0.5; Early-grafted group) and 30 children (20 boys and 10 girls; mean age = 5.5 years, SD 1.0; Non-grafted group) with complete unilateral cleft lip and palate repaired with a one-stage closure. The groups differed regarding the timing of alveolar bone grafting: in the Early-grafted group, alveolar bone grafting in combination with rhinoplasty (ABG-R) was performed between 2 and 4 years of age (mean age = 2.3 years; SD 0.6); in the Non-grafted group, the alveolar defect was grafted after 9 years of age. No primary nose correction was carried out in any group. To rate esthetics, a modified five-grade esthetic index of Asher-McDade was used, where grade 1 means the most esthetic and grade 5 - the least esthetic outcome. RESULTS Esthetics of full faces and of all nasolabial elements in the Early-grafted group was significantly better than in Non-grafted group. The scores in the Early-grafted group ranged from 2.30 to 2.66 points, whereas in the Non-grafted group ranged from 2.66 to 3.17 points. All intergroup differences were statistically significant (p < 0.05). CONCLUSIONS Three years post-operatively, early alveolar bone grafting combined with rhinoplasty is favorable for facial esthetics in children with UCLP, but a longer follow-up is needed to assess whether the improvement was permanent.

Stability and relapse after orthodontic treatment of deep bite cases-a long-term follow-up study.

The purpose of this long-term follow-up study was twofold-firstly, to assess prevalence of relapse after treatment of deep bite malocclusion and secondly, to identify risk factors that predispose patients with deep bite malocclusion to relapse. Sixty-one former patients with overbite more than 50% incisor overlap before treatment were successfully recalled. Clinical data, morphometrical measurements on plaster casts before treatment, after treatment and at long-term follow-up, as well as cephalometric measurements before and after treatment were collected. The median follow-up period was 11.9 years. Patients were treated by various treatment modalities, and the majority of patients received at least a lower fixed retainer and an upper removable bite plate during retention. Relapse was defined as increase in incisor overlap from below 50% after treatment to equal or more than 50% incisor overlap at long-term follow-up. Ten per cent of the patients showed relapse to equal or larger than 50% incisor overlap, and their amount of overbite increase was low. Among all cases with deep bite at follow-up, gingival contact and palatal impingement were more prevalent in partially corrected noncompliant cases than in relapse cases. In this sample, prevalence and amount of relapse were too low to identify risk factors of relapse.

Reproducibility and accuracy of linear measurements on dental models derived from cone-beam computed tomography compared with digital dental casts.

INTRODUCTION The aim of this study was to determine the reproducibility and accuracy of linear measurements on 2 types of dental models derived from cone-beam computed tomography (CBCT) scans: CBCT images, and Anatomodels (InVivoDental, San Jose, Calif); these were compared with digital models generated from dental impressions (Digimodels; Orthoproof, Nieuwegein, The Netherlands). The Digimodels were used as the reference standard. METHODS The 3 types of digital models were made from 10 subjects. Four examiners repeated 37 linear tooth and arch measurements 10 times. Paired t tests and the intraclass correlation coefficient were performed to determine the reproducibility and accuracy of the measurements. RESULTS The CBCT images showed significantly smaller intraclass correlation coefficient values and larger duplicate measurement errors compared with the corresponding values for Digimodels and Anatomodels. The average difference between measurements on CBCT images and Digimodels ranged from -0.4 to 1.65 mm, with limits of agreement values up to 1.3 mm for crown-width measurements. The average difference between Anatomodels and Digimodels ranged from -0.42 to 0.84 mm with limits of agreement values up to 1.65 mm. CONCLUSIONS Statistically significant differences between measurements on Digimodels and Anatomodels, and between Digimodels and CBCT images, were found. Although the mean differences might be clinically acceptable, the random errors were relatively large compared with corresponding measurements reported in the literature for both Anatomodels and CBCT images, and might be clinically important. Therefore, with the CBCT settings used in this study, measurements made directly on CBCT images and Anatomodels are not as accurate as measurements on Digimodels.

Nasolabial appearance after two palatoplasty types in cleft lip and palate.

BACKGROUND Facial appearance is important for normal psychosocial development in children with cleft lip and palate (CLP). There is conflicting evidence on how deficient maxillary growth may affect nasolabial esthetics. METHODS We retrospectively investigated nasolabial appearance in two groups, the Langenback (35 children; mean age 11.1 years; range: 7.9-13.6) and Vomerplasty (58 children; mean age 10.8 years; range: 7.8-14), who received unilateral CLP surgery by the same surgeon. The hard palate repair technique differed between the two groups. In the Langenback group, palatal bone on the non-cleft side only was left denuded, inducing scar formation and inhibiting maxillary growth. In the Vomerplasty group, a vomerplasty with tight closure of the soft tissues on the palate was applied. Thirteen lay judges rated nasolabial esthetics on photographs using a modified Asher-McDade's index. RESULTS Nasolabial esthetics in both groups was comparable (p > 0.1 for each nasolabial component). Inferior view was judged as the least esthetic component and demonstrated mean scores 3.18 (SD = 0.63) and 3.13 (SD = 0.47) in the Langenback and Vomerplasty groups, respectively. Mean scores for other components were from 2.52 (SD = 0.63) to 2.81 (SD = 0.62). Regression analysis showed that vomerplasty is related with slight improvement in the nasal profile only (coefficient B = -0.287; p = 0.043; R(2 ) = 0.096). CONCLUSIONS This study demonstrates that the use of vomerplasty instead of the Langenbeck technique is weakly associated with the nasolabial appearance among pre-adolescent patients with UCLP.

Success rate of paramedian palatal implants in adolescent and adult orthodontic patients: a retrospective cohort study.

The purpose of this study was to examine the success rate of paramedian palatal Orthosystem first- and second-generation implants used for anchorage in orthodontic treatment in patients treated by one experienced orthodontist. The records of 143 patients (90 female, 53 male, median age: 15.7 years, range: 10.2-50.9) receiving 145 palatal implants of the first or second generation (Orthosystem, Straumann AG, Basel, Switzerland) were examined. All the palatal implants were placed in a paramedian palatal location by three experienced surgeons. Stable implants were orthodontically loaded after a healing period of 3 months. Out of the 145 inserted paramedian palatal implants only seven implants (4.8%) were not considered stable after insertion. All the successfully osseointegrated implants remained stable during orthodontic treatment. Paramedian palatal implants are highly reliable and effective devices to obtain skeletal anchorage for orthodontic treatment. This study has shown that the paramedian location is a good alternative to the median location.

Temporary anchorage device usage: a survey among Swiss orthodontists.

BACKGROUND The aim of the survey was to obtain information on the treatment plan preferences, mechanics and characteristics of temporary anchorage device (TAD) application using a single case presented to orthodontists in Switzerland. METHODS A structured questionnaire to be completed by all study participants with case-specific (treatment plan including mechanics and TAD usage) and general questions (general fixed appliance and TAD usage as well as professional, educational and demographic questions) together with an orthodontic borderline case was utilised. The case was a female adult with dental Class II/2, deep bite and maxillary anterior crowing, who had been treated in childhood with extraction of four premolars and fixed appliance followed by wisdom tooth extraction. RESULTS The response rate was 24.4% (108 out of 443). The majority (96.3%, 104) proposed comprehensive treatment, while 3.7% (4) planned only alignment of maxillary teeth. 8.3% (9) included a surgical approach in their treatment plan. An additional 0.9% (1) combined the surgical approach with Class II mechanics. 75.1% (81) decided on distalization on the maxilla using TADs, 7.4% (8) planned various types of Class II appliances and 3.7% (4) combined distalization using TADs or headgear with Class II appliances and surgery. Palatal implants were the most popular choice (70.6%, 60), followed by mini-screws (22.4%, 19) and mini-plates on the infrazygomatic crests (7.0%, 6). The preferred site of TAD insertion showed more variation in sagittal than in transversal dimension, and the median size of mini-screws used was 10.0-mm long (interquartile range (IQR) 2.3 mm) and 2.0-mm wide (IQR 0.3 mm). CONCLUSIONS Distalization against palatal implants and then distalization against mini-screws were the most popular treatment plans. Preferred site for TAD insertion varied depending on type and size but varied more widely in the sagittal than in the transversal dimension.

Microstructural and mechanical characterization of contemporary lingual orthodontic brackets.

OBJECTIVES To investigate the composition and the microstructural and mechanical characterization of three different types of lingual brackets. MATERIALS AND METHODS Incognito™ (3M Unitek), In-Ovation L (DENTSPLY GAC) and STb™ (Light Lingual System, ORMCO) lingual brackets were studied under the scanning electron microscope employing backscattered electron imaging and their elemental composition was analysed by energy-dispersive X-ray microanalysis. Additionally, Vickers hardness was assessed using a universal hardness-testing machine, and the indentation modulus was measured according to instrumented indentation test. Two-way analysis of variance was conducted employing bracket type and location (base and wing) as discriminating variable. Significant differences among groups were allocated by post hoc Student-Newman-Keuls multiple comparison analysis at 95% level of significance. RESULTS Three different phases were identified for Incognito and In-Ovation L bracket based on mean atomic number contrast. On the contrary, STb did not show mean atomic contrast areas and thus it is recognized as a single phase. Incognito is a one-piece bracket with the same structure in wing and base regions. Incognito consists mainly of noble metals while In-Ovation L and STb show similar formulations of ferrous alloys in wing and base regions. No significant differences were found between ferrous brackets in hardness and modulus values, but there were significant differences between wing and base regions. Incognito illustrated intermediate values with significant differences from base and wing values of ferrous brackets. CONCLUSIONS/IMPLICATIONS Significant differences exist in microstructure, elemental composition, and mechanical properties among the brackets tested; these might have a series of clinical implications during mechanotherapy.

Indication and timing of soft tissue augmentation at maxillary and mandibular incisors in orthodontic patients. A systematic review.

OBJECTIVE To assess the indication and timing of soft tissue augmentation for prevention or treatment of gingival recession when a change in the inclination of the incisors is planned during orthodontic treatment. MATERIALS AND METHODS Electronic database searches of literature were performed. The following electronic databases with no restrictions were searched: MEDLINE, EMBASE, Cochrane, and CENTRAL. Two authors performed data extraction independently using data collection forms. RESULTS No randomized controlled trial was identified. Two studies of low-to-moderate level of evidence were included: one of prospective and retrospective data collection and one retrospective study. Both implemented a periodontal intervention before orthodontics. Thus, best timing of soft tissue augmentation could not be assessed. The limited available data from these studies appear to suggest that soft tissue augmentation of bucco-lingual gingival dimensions before orthodontics may yield satisfactory results with respect to the development or progression of gingival recessions. However, the strength of the available evidence is not adequate in order to change or suggest a possible treatment approach in the daily practice based on solid scientific evidence. CONCLUSIONS Despite the clinical experience that soft tissue augmentation of bucco-lingual gingival dimensions before orthodontic treatment may be a clinically viable treatment option in patients considered at risk, this treatment approach is not based on solid scientific evidence. Moreover, the present data do not allow to draw conclusions on the best timing of soft tissue augmentation when a change in the inclination of the incisors is planned during orthodontic treatment and thus, there is a stringent need for randomized controlled trials to clarify these open issues.

Localization of impacted maxillary canines and root resorption of neighbouring teeth: a study assessing the diagnostic value of panoramic radiographs in two groups of observers.

OBJECTIVES To assess the diagnostic value of panoramic views (2D) of patients with impacted maxillary canines by a group of trained orthodontists and oral surgeons, and to quantify the subjective need and reasons for further three-dimensional (3D) imaging. MATERIALS AND METHODS The study comprises 60 patients with panoramic radiographs (2D) and cone beam computed tomography (CBCT) scans (3D), and a total of 72 impacted canines. Data from a standardized questionnaire were compared within (intragroup) and between (intergroup) a group of orthodontists and oral surgeons to assess possible correlations and differences. Furthermore, the questionnaire data were compared with the findings from the CBCT scans to estimate the correlation within and between the two specialties. Finally, the need and reasons for further 3D imaging was analysed for both groups. RESULTS When comparing questionnaire data with the analysis of the respective CBCT scans, orthodontists showed probability (Pr) values ranging from 0.443 to 0.943. Oral surgeons exhibited Pr values from 0.191 to 0.946. Statistically significant differences were found for the labiopalatal location of the impacted maxillary canine (P = 0.04), indicating a higher correlation in the orthodontist group. The most frequent reason mentioned for the further need of 3D analysis was the labiopalatal location of the impacted canines. Oral surgeons were more in favour of performing further 3D imaging (P = 0.04). CONCLUSIONS Orthodontists were more likely to diagnose the exact labiopalatal position of impacted maxillary canines when using panoramic views only. Generally, oral surgeons more often indicated the need for further 3D imaging.

Factorial designs: an overview with applications to orthodontic clinical trials.

Factorial designs for clinical trials are often encountered in medical, dental, and orthodontic research. Factorial designs assess two or more interventions simultaneously and the main advantage of this design is its efficiency in terms of sample size as more than one intervention may be assessed on the same participants. However, the factorial design is efficient only under the assumption of no interaction (no effect modification) between the treatments under investigation and, therefore, this should be considered at the design stage. Conversely, the factorial study design may also be used for the purpose of detecting an interaction between two interventions if the study is powered accordingly. However, a factorial design powered to detect an interaction has no advantage in terms of the required sample size compared to a multi-arm parallel trial for assessing more than one intervention. It is the purpose of this article to highlight the methodological issues that should be considered when planning, analysing, and reporting the simplest form of this design, which is the 2 × 2 factorial design. An example from the field of orthodontics using two parameters (bracket type and wire type) on maxillary incisor torque loss will be utilized in order to explain the design requirements, the advantages and disadvantages of this design, and its application in orthodontic research.