Effectiveness of the open bite treatment in growing children and adolescents. A systematic review

Long-term effectiveness of non-surgical open-bite treatment: a systematic review and meta-analysis

BACKGROUND

The etiology of open bite is complex, involving various genetic or environmental factors. Several treatment alternatives have been suggested for the correction of open bite, yet their long-term effectiveness remains controversial.

OBJECTIVE

To assess the long-term effectiveness of open-bite treatment in treated with non-surgical approaches versus untreated patients, through lateral cephalometric radiographs.

SEARCH METHODS

Unrestricted search of 16 electronic databases and manual searches up to November 2022.

SELECTION CRITERIA

Randomized or non-randomized controlled trials reporting on the long-term effects of open-bite treatment through angular lateral cephalometric variables.

DATA COLLECTION AND ANALYSIS

Only angular variables on lateral cephalometric radiographs were considered as primary outcomes. For each outcome, the mean differences and 95% confidence intervals were calculated using the random-effects model to consider existing heterogeneity. The revised Cochrane risk-of-bias tool (R.o.B. 2.0) and the risk-of-bias tool for non-randomized studies for interventions (ROBINS-I) were utilized for the randomized and non-randomized trials, respectively.

RESULTS

From the initially identified 26,527 hits, only 6 studies (1 randomized and 5 retrospective controlled trials) were finally included in this systematic review reporting on 244 open-bite individuals (134 patients and 110 untreated controls), while five of them were included in the meta-analyses, assessing either the interval ranging from treatment start to post-retention (T3-T1) or from end of treatment to post-retention period (T3-T2). Regarding the vertical plane, for the T3-T2 interval, no significant differences were found for the assessed skeletal measurements, indicating a relative stability of the treatment results. Similarly, with regard to the T3-T1 interval, no significant differences could be identified for the examined skeletal variables, implying that the produced effects are rather minimal and that the correction of the open bite was performed mainly through dentoalveolar rather than skeletal changes. Further, no significant changes could be identified regarding the inclination of the upper and lower incisors. Only the nasolabial angle was significantly reduced in the treated patients in the long term.

CONCLUSIONS

According to existing evidence, the influence of non-surgical treatment of open bite on the skeletal tissues and the inclination of the incisors is rather minimal in the long term, while only the nasolabial angle was significantly reduced.

Long term stability of a high-angle skeletal Class II open bite treated with high-pull headgear and modified transpalatal arch: A case report

This case report describes the treatment of an adolescent patient with an Angle Class II malocclusion, severe open bite and overjet, proclined incisors, skeletal Class II anteroposterior dysplasia, high mandibular plane angle and convex profile. The importance of stopping of a prolonged thumb sucking habit, which was a major causative factor of the open bite is discussed. A combination of a high-pull headgear and a modified transpalatal arch with a loop embedded with resin, at a distance from the palate, were used along with an Edgewise appliance. Treatment timing, favourable growth and good patient response led to an optimal outcome with excellent stability of the treatment results five years and five months post-treatment.

Evaluation of Soft and Hard Tissue Changes Following the Use of Rapid Molar Intruder for the Management of Skeletal Anterior Open Bite in Mixed Dentition: A Randomized Controlled Trial

Objective The aim of the study was to evaluate skeletal, dentoalveolar, and soft tissue changes following early anterior open bite (AOB) treatment using a rapid molar intruder (RMI). Materials and methods A two-arm, parallel-group, randomized controlled trial was conducted on 40 patients aged 8-12 years with anterior open bites. They were randomly allocated to the RMI group and the untreated control group (UCG) with a 1:1 allocation ratio. At the beginning of the treatment (T1) and after nine months of treatment (T2), lateral cephalometric images were taken of each patient. The primary outcome measures were skeletal, dentoalveolar, and soft tissue changes. A two-sample t-test was used in the intergroup comparisons of the cephalometric measurement. Results The findings showed that the overbite increased significantly in the RMI group compared to the control group (x = 4.44 mm, x = 0.19 mm, respectively; p<0.001). A statistically significant intrusion of the upper and lower first molars was observed in the RMI group (x = 2.9 mm, x = 1.54 mm, respectively) compared to a slight extrusion in the control group. The differences between the two groups were significant (p<0.001). The SN: GoMe angle and the sum of Bjork decreased significantly in the RMI group compared to an increase observed in the control group. The differences between the two groups were significant (p<0.001). Conclusion The rapid molar intruder is an effective appliance for correcting anterior open bites in mixed dentition, inducing favorable skeletal, dentoalveolar, and soft tissue changes.

Influence of rapid maxillary expansion in the stability of anterior open bite treatment

OBJECTIVES

This study aimed to compare the stability of anterior open bite (AOB) in patients treated with and without rapid maxillary expansion (RME) before fixed palatal crib (PC) therapy in the mixed dentition.

MATERIAL AND METHODS

Expansion/palatal crib group (EPC) was comprised of 25 patients (10 male, 15 female, mean initial age of 7.8 years) with AOB treated with RME before PC therapy. Palatal crib group (PC) included 25 patients with AOB (10 male, 15 female, mean initial age of 8.0 years) treated only with PC therapy. Lateral cephalograms were analyzed at pre-treatment (T0), after PC therapy (T1), and 3 years after PC removal (T2) in both groups. AOB relapse was considered when a negative overbite was observed at T2. Intergroup comparisons of interphase changes were performed using t and Mann-Whitney tests (p < 0.05).

RESULTS

Treatment and post-treatment alterations showed similar changes in both groups for all cephalometric variables. Overall changes from T0 to T2 were similar between the groups except for the maxillary incisors that tipped lingually in PC group (1.PP =  - 3.37°) and labially in EPC group (1.PP = 1.76°). The frequency of AOB relapse was 8% and 4% in the EPC and PC groups, respectively. Treatment time in the EPC group (9.7 months) was shorter (p = 0.024) when compared to the PC group (11.0 months).

CONCLUSIONS

In the mixed dentition, stability of AOB treated with RME before fixed PC therapy was similar to PC therapy alone. However, treatment time with fixed PC was slightly shorter in the group treated with RME.

CLINICAL RELEVANCE

This study aims to understand if RME performed previously to fixed palatal crib contributes to the index of stability of AOB treatment in the mixed dentition.

Evaluation of the acceleration, skeletal and dentoalveolar effects of low-level laser therapy combined with fixed posterior bite blocks in children with skeletal anterior open bite: A three-arm randomised controlled trial

OBJECTIVES

To evaluate the effectiveness of the low-level laser therapy (LLLT) in accelerating the early treatment of the skeletal anterior open bite (AOB) and to evaluate the associated skeletal and dentoalveolar changes.

MATERIALS AND METHODS

A three-arm, parallel-group, randomized controlled trial was conducted on 42 patients aged 8-10 years with skeletal AOB. Patients were randomly allocated to three groups: the fixed posterior bite block+low-level laser therapy (FPBB+LLLT) group; the fixed posterior bite block (FPBB) group; and the untreated control group (UCG) in a 1:1:1 allocation ratio. The LLLT dose in the FPBB+LLLT group was applied using 808-nm wavelength Ga-Al-As semiconductor laser device with the energy of 4-joules/point and irradiation time of 16 seconds/point. LLLT was applied in the first visit; then, it was applied on day 3, 7 and 14 of the first month. Afterwards, it was applied every 15 days until the end of the treatment. Lateral cephalometric images were taken at the beginning of the treatment (T0) and at the end of the active phase (T1). The primary outcome measures were the overall time needed to correct the AOB and the skeletal and dentoalveolar changes.

RESULTS

The correction of the AOB required significantly less mean time in the FPBB+LLLT group compared to the FPBB group (x̅=7.07, x̅=9.42 months, respectively; P=0.001). The mean upper first molar intrusion in the FPBB+LLLT group was 1.21mm and significantly greater than that of the FPBB group (0.82mm; P=0.018). However, there was a slight mean extrusion of the upper first molar in the UCG (0.32mm).

CONCLUSIONS

The overall time needed to correct the AOB was shorter in the FPBB+LLLT group. The LLLT appeared to be effective in accelerating orthodontic tooth movement. FPBB alone or LLLT were effective in the early treatment of anterior open bite (AOB). The two interventional groups produced similar dentoalveolar and skeletal changes; most of which were dentoalveolar in the correction of the anterior open bite.

Stability of early anterior open bite treatment: a 2-year follow-up randomized clinical trial

This 2-year-follow up study compared and evaluated the stability of early anterior open bite (AOB) treatment based on different appliances. Children from 7 to 10 years with Angle Class I, AOB larger than 1.0 mm and fully erupted maxillary and mandibular permanent central incisors were eligible. The initial sample was 99 patients distributed, by simple randomization, into four groups: BS (bonded spurs), CC (chincup), FPC (fixed palatal crib) and RPC (removable palatal crib). Cephalometric analysis was performed at baseline (T1), final (T2) and 2-year post-treatment (T3) by taking the overbite measurements as the main outcome. Blinding was possible to cephalometric analysis. At T3, with dropouts, there were 63 individuals, being BS (n=15; overbite 0.19 mm; 11.54 years; 10 female (F)/5 male (M)); CC (n=11; overbite -0.19 mm; 11.41 years; 8 F/3 M); FPC (n=21; overbite 1.23 mm; 11.44 years; 15 F/6 M) and; RPC (n=16; overbite 0.73 mm; 11.67 years; 6 F/10 M). Changes in dentoskeletal variables and breaking deleterious oral habits during the follow up were statically analyzed with p<.05. Mandibular skeletal linear measurements and vertical dental components have gradually increased with age, manly at pubertal growth spurt and at the establishment of permanent dentition after treatment. Incisor teeth extrusion had impact on AOB correction and stability in 4 groups, which recorded a 1.15 mm-improvement of overbite after treatment (T3-T2). The experimental appliances were effective with stable results, being FPC the device recorded the highest AOB correction and the lowest patient withdrawal rate.

Dental arch changes after open bite treatment with spurs associated with posterior build-ups in the mixed dentition: A randomized clinical trial

INTRODUCTION

This single-center, 2-arm, parallel-group randomized clinical trial aimed to compare the dimensional dental arch changes after anterior open bite (AOB) treatment with bonded spurs associated with posterior build-ups vs bonded spurs alone.

METHODS

Patients aged between 7 and 11 years with AOB were recruited at a university clinic and randomly allocated into 2 groups. The experimental group was treated with bonded spurs associated with posterior build-ups (SBU) and the comparison group with bonded spurs alone (S). Digital dental models were obtained at pretreatment and after 12 months of treatment. The overbite change was the primary outcome. The randomization list was obtained at the Web site www.randomization.com. Allocation concealment involved sequentially numbered, sealed, and opaque envelopes. The outcomes' assessment was blinded. Analysis of covariance was used for intergroup comparisons (P <0.05). Mean difference (MD) and 95% confidence interval (CI) were obtained.

RESULTS

Twenty-four patients (mean age, 8.22 ± 1.06 years; 7 males and 17 females) were included in the SBU group, and 25 patients (mean age, 8.30 ± 0.99 years; 11 males and 14 females) were included in the comparison group. After a 12-month follow-up, the overbite increased approximately 4 mm in both groups (MD, -0.11 mm; 95% CI, -1.03 to 0.80). Means of anterior dentoalveolar vertical development ranged from 2.24 mm (S group) to 2.49 mm (SBU group) and from 1.31 mm (SBU group) to 1.55 mm (S group) for the maxilla (MD, -0.24 mm; 95% CI, -0.91 to 0.44) and mandible (MD, 0.29 mm; 95% CI, -0.39 to 0.96), respectively. The maxillary intermolar distance decreased in the SBU group and increased in the S group (MD, -0.48 mm; 95% CI, -0.92 to -0.03). The mandibular intermolar distance increased in the SBU group and decreased in the comparison group (MD, 0.26 mm; 95% CI, 0.004-0.52). Plaque accumulation around the spurs was observed in some patients.

CONCLUSIONS

Both protocols demonstrated similar improvements in the AOB with similar effects on the dental arches. The SBU group showed a slight decrease in the maxillary intermolar distance and a slight increase in the mandibular intermolar distance, whereas opposite changes were observed for the S group.

REGISTRATION

This trial was registered at Clinicaltrials.gov (Identifier NCT03702881).

PROTOCOL

The study protocol was not published.

FUNDING

This work was supported by the São Paulo Research Foundation (FAPESP) grants nos. 2017/06440-3, 2018/05238-9, and 2018/24003-2; and financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior-Brasil (CAPES), Finance Code 001.

Anterior open bite and its relationship with dental arch dimensions and tongue position during swallowing and phonation in individuals aged 8-16 years: A retrospective case-control study

OBJECTIVE

To determine the relationship between AOB and factors such as dental arch dimensions and tongue position during swallowing and phonation.

MATERIAL AND METHODS

A case-control study was performed in two groups: 132 children with Anterior Open Bite (AOB) and 132 with normal vertical overbite (NVO), aged 8-16 years selected from the records taken by a previous study from five public schools. Dental arch dimensions were assessed through digitalized study models. Swallowing was evaluated using the Payne technique, and phoniatric assessment included an adaptation of the articulation test used to describe phonemes.

STATISTICAL ANALYSIS

Chi-Square or Fisher's exact test for comparisons between qualitative variables and the Mann Whitney or T-student were applied to compare the dental arch dimensions according to bite type. A logistic regression model was applied to control the effect of confusion between independent variables and to describe its simultaneous effect on the type of bite.

RESULTS

Intercanine, interpremolar and intermolar widths showed higher values in AOB patients with a mean deviation (MD) of 0.536 (P=0.031), 0.60 (P=0.043) and 1.15, (P<0.001) respectively. Distortions caused by tongue interposition and thrust, tongue protrusion during swallowing, mandibular arch intermolar width, total maxillary arch length, maxillary arch perimeter, and posterior arch depth accounted for 64.6% of AOB and allowed for correct predictions in 83.8% of the cases observed in the study population.

CONCLUSIONS

A significant association between tongue position and function, as well as alterations such as tongue interposition and thrust during swallowing and phonation in individuals with AOB, were observed. There is a relationship between AOB and the presence of a wider mandibular arch and a narrower, longer, and deeper maxillary arch.

Assessment of the duration of the pubertal growth spurt in patients with skeletal open bite : A cross-sectional study

PURPOSES

The objectives were to assess the skeletal age of patients with skeletal open bite and to estimate and compare the mean chronological age related to CS3 and CS4 (cervical stage, CS) and the duration of the pubertal growth spurt (PGS).

METHODS

Orthodontic records of 145 patients were analyzed in this retrospective cross-sectional study. The study group comprised 104 patients with skeletal open bite (angle between cranial base plane line [NS] and mandible base plane line [ML] > 39° according to Steiner), whereas the control group comprised 41 patients with normal anteroposterior and vertical measurements. Skeletal age was assessed using the 6‑stage CVM (cervical vertebral maturation) method according to Baccetti. Quantitative variables were characterized by means of the arithmetic mean and standard deviation. The PGS duration was calculated as the difference between the means of the chronological ages related to CS3 and CS4.

RESULTS

In the study group, the arithmetic means related to CS3 and CS4 were 11.12 and 13.54 years, respectively; the duration of the PGS was 2.42 years. In the control group, the arithmetic means related to CS3 and CS4 were 10.71 and 11.82 years, respectively; the duration of the PGS was 1.11 years.

CONCLUSIONS

In patients with skeletal open bite, the duration of PGS is longer but it occurs at a similar chronological age compared to patients with normal anteroposterior and vertical measurements. The PGS in males begins later than in females. Knowledge on the longer growth spurt in patients with skeletal open bite compared to patients with normal anteroposterior and vertical relationships can be useful in the selection of an appropriate therapeutic method and also provides information about the possibility of a longer and thus more effective orthopedic approach directed at positive change in the vertical growth pattern during intense bone remodeling.

Dentoskeletal changes in open bite treatment using spurs and posterior build-ups: A randomized clinical trial

INTRODUCTION

This single-center 2-arm parallel randomized clinical trial aimed to compare the dentoskeletal effects of bonded spurs combined with posterior build-ups vs conventional bonded spurs in the treatment of anterior open bite malocclusion in the mixed dentition.

METHODS

Patients aged from 7 to 11 years with anterior open bite, recruited at a university orthodontic clinic, were randomly allocated into 2 groups. The experimental group consisted of patients treated with bonded spurs combined with posterior build-ups. The comparison group comprised patients treated with conventional bonded spurs. Lateral headfilms were obtained at pretreatment and after 12 months of treatment. The primary outcome was the change in the overbite. Randomization was performed using the Web site www.randomization.com. Sequentially numbered opaque and sealed envelopes were used for allocation concealment. Blinding was applicable for outcome assessment only. Intergroup comparisons were performed using t or Mann-Whitney U tests (P <0.05). Mean difference (MD) and 95% confidence interval (CI) were obtained.

RESULTS

The experimental group included 24 patients (17 female, 7 male; mean age, 8.22 ± 1.06 years) and the comparison group comprised 25 patients (14 female, 11 male; mean age, 8.30 ± 0.99 years). Baseline demographic and cephalometric characteristics were similar between groups. After 12 months, all patients showed improvements. Both groups showed similar improvements of the overbite (MD, 0.00 mm; 95% CI, -0.92 to 0.91), similar slight decreases of the gonial (MD, 0.02°; 95% CI, -1.11 to 1.15) and mandibular plane (MD, 0.15°; 95% CI, -0.64 to 0.93) angles, and similar mandibular molar extrusion (MD, 0.14 mm; 95% CI, -0.27 to 0.56). The experimental group showed significantly smaller extrusion of the maxillary first molar than the comparison group (MD, -0.70 mm; 95% CI, -0.92 to -0.49). The other dentoskeletal variables showed similar changes without statistically significant intergroup differences. No serious harm was observed other than plaque accumulation around the spurs.

CONCLUSIONS

Similar overbite increases and dentoskeletal changes were observed in both groups after 12 months of treatment. Although the experimental group showed significantly smaller extrusion of the maxillary molars, no greater counterclockwise rotation of the mandible than the comparison group was observed.

REGISTRATION

This trial was registered at Clinicaltrials.gov (Identifier NCT03702881).

PROTOCOL

The protocol was not published.

FUNDING

This trial was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES), Finance Code 001; and by grants: no. 2017/06440-3, no. 2018/05238-9 and no. 2018/24003-2, São Paulo Research Foundation (FAPESP).

Comparison Between Removable and Fixed Devices for Nonskeletal Anterior Crossbite Correction in Children and Adolescents: A Systematic Review

OBJECTIVE

To compare removable and fixed orthodontic devices in the correction of non-skeletal anterior crossbite in children and adolescents in the mixed dentition.

MATERIALS AND METHODS

Electronic searches were conducted in the following databases: PubMed, Web of Science, Scopus, Medline Ovid, Lilacs, US Clinical Trials, and Proquest. A hand search of the reference lists of the included articles and a Google Scholar search were also conducted. References were evaluated by 2 review authors. Articles that met the eligibility criteria were included. Data extraction, methodological quality assessment (Cochrane tool), and strength of the evidence evaluation (GRADE) were also carried out.

RESULTS

Seven articles were included. The results showed that removable and fixed devices were equally efficacious for overjet correction. Removable and fixed devices can also present inconveniences regarding pain and discomfort levels, the accomplishment of everyday activities (leisure and school), and the performance of functions, such as chewing and speech. However, treatment time and costs were significantly lower in orthodontic therapy with fixed appliances. Sequence generation, allocation concealment, and complete outcome data were not a concern. Blinding of participants or personnel was not reported in any article, and blinding of the assessor was a concern in 2 articles. Selective reporting was a concern in 2 articles. The certainty of the evidence for overjet correction was very low.

CONCLUSION

Removable and fixed orthodontic devices are efficacious for overjet correction in non-skeletal anterior crossbite. However, treatment time and costs are lower for cases treated with fixed devices.

Clinical implications of age-related change of the mandibular plane angle

OBJECTIVE

To identify trajectories of ontogenetic change in the mandibular plane angle (MPA) and to describe the influence of sex and other factors on MPA during growth.

SETTING/SAMPLE

The data consisted of 7026 MPA measurements from lateral cephalographs representing longitudinal series from ages 6 to 21 for 728 individuals from the Craniofacial Growth Consortium Study (CGCS).

MATERIALS AND METHODS

Facial type was determined from MPA for each assessment, with the assessment closest to age 18 representing the adult facial type. The sample includes 366 males and 362 females, each with between 2 and 15 cephalographs. The mean number of cephalographs per individual is 10. Variation in childhood MPA (earliest assessment between 6 and 9 years of age) and adult MPA (closest assessment to age 18 between 15 and 21 years of age), and change in MPA from childhood to adulthood were compared by sex and adult facial type using ANOVA and post hoc t tests.

RESULTS

Mandibular plane angle decreased from childhood to adulthood in 92% of males and 81% of females, yet increased in 36% of males and 50% of females with the hyper-divergent adult facial type. Childhood MPA and overall change in MPA were significantly different by adult facial type.

CONCLUSIONS

Adult facial type is associated with differences in childhood MPA and change in MPA during growth. There are multiple ontogenetic pathways by which an individual can achieve a normo-divergent adult facial type, and an individual's childhood MPA does not necessarily correspond to his or her adult facial type.

Effect of orthodontic management and orofacial muscle training protocols on the correction of myofunctional and myoskeletal problems in developing dentition. A systematic review and meta-analysis

The aim of this review was to evaluate available evidence on the effect of early orthodontic management and myofunctional treatment in the developing dentition children, on anterior open bite correction, as well as on normalization of patterns of mouth breathing, swallowing and tongue resting position and pressure. Electronic searches in MEDLINE, Cochrane and LILACS, without language restrictions were conducted. Additionally, unpublished literature was identified. Randomized controlled trials, or controlled clinical trials, comparing interventions applied to manage anterior open bite and other muscle functions such as breathing/swallowing pattern and tongue resting position and pressure, were considered. Quality assessment was based on the Cochrane Risk of Bias tool. Random effects meta-analyses were conducted to assess treatment effects. From the 265 initial search results, 15 articles were included in the review. Eight were randomized controlled trials (RCTs) and 7 were controlled clinical trials. Treatment outcomes comprised skeletal and dentoalveolar changes recorded cephalometrically, mouth posture and lip closure normalization, improvement of tongue resting position/pressure and modification of swallowing pattern. Quantitative synthesis was possible for only 2 of the included RCTs. There was no evidence to support bonded lingual spurs over banded fixed appliances for the correction of anterior open bite in mixed dentition children presenting nonnutritive oral habits at the onset of treatment (SMD: -0.03; 95%CI: -.81, 0.74; P = 0.94). Although early orthodontic management and myofunctional treatment in the deciduous and mixed dentition children appears to be a promising approach, the quality of the existing evidence is questionable.

Long-term evaluation of rapid maxillary expansion and bite-block therapy in open bite growing subjects: A controlled clinical study

OBJECTIVE

To evaluate the long-term effects of rapid maxillary expansion (RME) and posterior bite block (BB) in prepubertal subjects with dentoskeletal open bite.

MATERIALS AND METHODS

The treatment group (TG) comprised 16 subjects (14 girls, 2 boys) with dentoskeletal open bite with a mean age of 8.1 ± 1.1 years treated with RME and BB. Three consecutive lateral cephalograms were available before treatment (T1), at the end of the active treatment with the RME and BB (T2), and at a follow-up observation at least 4 years after the completion of treatment (T3). The TG was compared with a control group (CG) of 16 subjects (14 girls, 2 boys) matched for sex, age, and vertical skeletal pattern. An independent sample t-test was used to compare the T1 to T3, T1 to T2, and T2 to T3 cephalometric changes between the TG and the CG.

RESULTS

In the long term, the TG showed a significantly greater increase in overbite (+1.8 mm), reduced extrusion of maxillary and mandibular molars (-3.3 mm), and, consequently, a significant decrease in facial divergence (-2.8°) when compared with untreated subjects.

CONCLUSIONS

The RME and BB protocol led to successful and stable recovery of positive overbite in 100% of the patients considered. Correction of open bite was associated with reduced extrusion of maxillary and mandibular molars with a significant improvement in vertical skeletal relationships when compared with the CG.

Dentoskeletal effects produced by removable palatal crib, bonded spurs, and chincup therapy in growing children with anterior open bite

OBJECTIVE

To evaluate the dentoskeletal effects of different anterior open bite treatment modalities in children.

MATERIALS AND METHODS

This cephalometric study assessed changes resulting from different treatment approaches on 77 growing children with anterior open bite. A control group (n = 30) was used for comparison. Lateral cephalograms were available before treatment and after 12 months. The sample was divided into four groups: removable palatal crib associated with a chincup (G1), bonded spurs associated with a chincup (G2), chincup (G3), and nontreated control (G4). Statistical comparisons among the four groups were performed on T1 and the treatment changes using analysis of variance with Tukey's post hoc tests.

RESULTS

No statistically significant changes in skeletal variables were found among the groups, except for lower anterior face height (LAFH) increase in G1. Overall, effects in all of the treated groups were exclusively dentoalveolar. A larger overbite (OB) increase was observed in G1 and G2 when compared with G3 and G4. The maxillary incisors in G1 showed increased palatal tipping, retrusion, and more vertical dentoalveolar development as well as increased lingual tipping among mandibular incisors. There was less vertical development of maxillary and mandibular molars in G3.

CONCLUSIONS

A removable palatal crib provided an improvement in OB (97.5%), followed by the bonded spurs (84.5%). Conversely, the chincup-only group did not have positive OB effects.

Systematic review for orthodontic and orthopedic treatments for anterior open bite in the mixed dentition

Background

The treatment options for the early treatment of anterior open bite are still controversial. The aim of this study was to evaluate the actual available evidence on treatments of anterior open bite in the mixed dentition in order to assess the effectiveness of the early treatment in reducing open bite, the most efficacious treatment strategy and the stability of the results.

Materials and methods

A literature survey was done on November 15, 2015, by means of appropriate Medical Subject Headings (MeSH) using the following databases: PubMed, EMBASE, Cochrane Library, LILACS, VHL, and WEB OF SCIENCE.

Randomized clinical trials and studies with a control group (treated or untreated) were then selected by two authors. Trials including patients with syndromes or in the permanent dentition and studies concerning treatment with extractions, full-fixed appliances, or surgery were not considered.

Full articles were retrieved for abstracts or titles that met the initial inclusion criteria or lacked sufficient detail for immediate exclusion.

Results

Two thousand five hundred sixty-nine studies about open bite were available; the search strategy selected 240 of them.

Twenty-four articles have been judged suitably for the final review, and their relevant data were analyzed.

Discussion

Although this review confirms the effectiveness of early treatment of open bite, particularly when no-compliance strategies are employed, meta-analysis was unfeasible due to lack of standardization, important methodological limitations, and shortcomings of the studies.

Conclusions

A more robust approach to trial design in terms of methodology and error analysis is needed. Besides, more studies with longer periods of follow-up are required.

Effect of molar intrusion with temporary anchorage devices in patients with anterior open bite: a systematic review

OBJECTIVE

The objective of the study is to assess the effect of molar intrusion with temporary anchorage devices on the vertical facial morphology and mandibular rotation during open bite treatment in the permanent dentition.

METHODS

We performed a systematic review of the published data in seven electronic databases up to September 2015. We considered studies for inclusion if they were examining the effects of posterior teeth intrusion on the vertical facial morphology with open bite malocclusion in the permanent dentition. Study selection, risk of bias assessment, and data-extraction were performed in duplicate. Meta-analysis was not possible due to dissimilarity and heterogeneity among the included studies.

RESULTS

Out of the 42 articles that met the initial eligibility criteria, 12 studies were finally selected. Low level of scientific evidence was identified after risk of bias assessment of the included studies with no relevant randomized controlled trial performed. Out of the 12 selected studies, five studies used miniplates and seven studies used miniscrews. Mandibular counterclockwise rotation was found to be between 2.3° and 3.9° in six studies (as sassed by mandibular plane angle, between MeGo or GoGn and SN or FH plane) while it was less than 2° in the remaining studies.

CONCLUSIONS

Current weak evidence suggests that molar intrusion with temporary anchorage devices may cause mandibular counterclockwise autorotation. Future well-conducted and clearly reported multicenter randomized controlled trials that include a non-treatment control group are needed to make robust recommendations regarding the amount of mandibular rotation during open bite treatments.