Evaluation of the open-bite Bionator versus the removable posterior bite plane with a tongue crib in the early treatment of skeletal anterior open bite: A randomized controlled trial

The Influence of the Tongue on the Development of Dental Malocclusion

The tongue supports the upper dental arch and encourages healthy dental arch development when it rests against the roof of the mouth. On the other hand, over time, malocclusion can result from incorrect tongue position, such as lying low in the mouth or thrusting forward during swallowing or speaking. As a muscular organ, the tongue applies forces to the jaws and teeth that may help with malocclusion or hinder it from aligning properly. The dentition and jaws grow and align according to the way the tongue, teeth, and surrounding structures interact. The tongue's morphogenetic function includes forming the arches and having an important impact on the maxillary complex's development. The tongue frequently assumes a balancing and compensatory function in subsequent phases, functioning more or less like a natural orthodontic bite. In adults, the tongue is able to compensate for problems like open bites, teeth that are out of alignment, or differences in the occlusal and sagittal planes of the spine. In this context, the tongue's ability to sustain occlusion during malocclusion can be considered a compensatory response. This is comparable to how lingual dysfunction may contribute to malocclusion or act as a potential source of recurring orthodontic instability. In order to diagnose and treat orthodontic issues, dental professionals must know the connection between tongue position and dental malocclusion. Malocclusion can be prevented or minimized with early intervention, such as myofunctional therapy to correct tongue position and habits, improving dental health and well-being overall.

Management Strategies for Open Bite Relapse: A Systematic Review and Meta-Analysis

The purpose of orthodontic therapy is to correct malocclusion and produce a stable outcome that endures over time. Long-term stability can be difficult to achieve, and many patients relapse after treatment, particularly in instances of open bite relapse (OBR). This systematic review aimed to analyze different types of management strategies for OBR and conduct a meta-analysis to find the best method of dealing with relapse. A comprehensive search was carried out across six major online databases using relevant keywords pertaining to our study, including "open bite relapse," "orthodontic retention," "orthodontic surgery," "orthodontic appliance," "orthodontic management," "orthodontic treatment," "orofacial myofunctional therapy (OMT)," "skeletal anchorage," and "treatment follow-up period." Eleven studies were selected after the application of relevant inclusion and exclusion strategies. The mean follow-up period of treatment for the studies ranged from six months to 4.5 years. Of all the management strategies assessed, OMT was found to be the least effective for OBR management. Surgical management modalities, such as mandibular repositioning and molar intrusion using skeletal anchorage, in conjunction with the usage of orthodontic appliances, were found to be noticeably effective, especially in the cases of participants who were <18 years of age. However, when utilized on a singular basis, either of them was found to be lacking the desired effect. The overall odds ratio (OR) of 0.48 (0.37, 0.64) and risk ratio (RR) of 0.62 (0.51, 0.74) were obtained after the meta-analysis of the different interventions for OBR, indicating statistical significance. There were only 11 studies included in the study, so it's possible that not all management strategies for OBR were fully understood. The limited number of studies may also have affected the generalizability of the findings. Although statistical differences were obtained to a certain degree, more clinical trials are needed to assess the effect of such surgical modalities as a viable management tool for OBR, since these represent a significant limiting factor in terms of the overall cost of the treatment placed upon the patient. Prior to the start of the research, registration was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) standards. The research protocol was created to meet the goals and was properly filed with the International Prospective Register of Systematic Reviews (PROSPERO) (CRD42023401991).

Assessment of the efficacy of various maxillary molar intrusion therapies: a systematic review

AIMS

To systematically assess the efficacy of the various interventions used to intrude maxillary molars. Furthermore, to evaluate associated root resorption, stability of intrusion, subsequent vertical movement of mandibular molars, cost effectiveness, compliance, patient reported outcomes and adverse events.

METHODS

A pre-registered and comprehensive literature search of published and unpublished trials until March 22nd 2023 with no language restriction applied in PubMed/Medline, Embase, Scopus, DOSS, CENTRAL, CINAHL Plus with Full Text, Web of Science, Global Index Medicus, Dissertation and Theses Global, ClinicalTrials.gov, and Trip (PROSPERO: CRD42022310562). Randomized controlled trials involving a comparative assessment of treatment modalities used to intrude maxillary molars were included. Pre-piloted data extraction forms were used. The Cochrane Risk of Bias tool was used for risk of bias assessment, and The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system was used for certainty of evidence appraisal.

RESULTS

A total of 3986 records were identified through the electronic data search, of which 24 reports were sought for retrieval. Of these, 7 trials were included. One trial was judged at high risk of bias, while the others had some concerns. Based on individual small sample studies, maxillary molar intrusion was achieved using temporary anchorage devices (TADs) and rapid molar intruder appliance (RMI). It was also observed to a lesser extent with the use of open bite bionator (OBB) and posterior bite blocks. The molar intruder appliance and the posterior bite blocks (spring-loaded or magnetic) also intruded the lower molars. Root resorption was reported in two studies involving TADs. None of the identified studies involved a comparison of conventional and TAD-based treatments for intrusion of molars. No studies reported outcomes concerning stability, cost-effectiveness, compliance and patient-reported outcomes. Insufficient homogeneity between the included trials precluded quantitative synthesis. The level of evidence was very low.

CONCLUSIONS

Maxillary molar intrusion can be attained with different appliances (removable and fixed) and with the use of temporary anchorage devices. Posterior bite blocks (spring-loaded or magnetic) and the RMI offer the additional advantage of intruding the mandibular molars. However, stability of the achieved maxillary molar intrusion long term is unclear. Further high-quality randomized controlled trials are needed.

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.

Three-dimensional dentoalveolar changes in open bite treatment in mixed dentition, spurs/posterior build-ups versus spurs alone: 1-year follow-up randomized clinical trial

This randomized clinical trial aimed to compare the three-dimensional dentoalveolar maxillary changes after anterior open bite treatment with bonded spurs and build-ups versus bonded spurs alone. Patients from 7 to 11 years of age with anterior open bite were randomly allocated into two groups. Bonded spurs and posterior build-ups were used in the experimental group and only bonded spurs were used in the comparison group. The randomization sequence was generated at www.randomization.com. Opaque, sealed and sequentially numbered envelopes were part of the allocation concealment. Digital dental models were acquired before (T1) and after 12 months of treatment (T2) and de-identified for analysis purposes. Three-dimensional changes of maxillary permanent incisors and first molars were evaluated by means of T1 and T2 dental model superimposition. Landmark-based registration on the posterior teeth and registration on the palate using regions of interest were performed. T or Mann–Whitney U tests were used for intergroup comparisons (P < 0.05). Mean difference (MD) and 95% confidence interval (CI) were calculated. Twenty-four children (17 girls and 7 boys) were included in the experimental group (mean age 8.22 ± 1.06 years) and 25 children (14 girls and 11 boys) were included in the comparison group (mean age 8.30 ± 0.99 years). After 12 months of treatment, inferior displacements of maxillary incisors were similar in the experimental (1.55–2.92 mm) and comparison (1.40–2.65 mm) groups. Inferior displacement of the maxillary molars was also similar in both groups (MD: − 0.13 mm; 95% CI − 0.38, 0.12). The experimental and comparison groups showed medial and lateral displacements of the permanent first molars, respectively (MD, − 0.31 mm; 95% CI − 0.51, − 0.11). Lingual inclination of the permanent first molars were observed in the experimental group and buccal inclination in the comparison group (MD, − 2.16°; 95% CI − 3.72, − 0.60). Similar three-dimensional displacements of maxillary central and lateral incisors, and inferior displacements of maxillary permanent first molars were observed in both groups. Bonded spurs associated with posterior build-ups demonstrated some medial displacement and lingual inclination of the maxillary permanent first molars while opposite changes were noticed in the comparison group.

Trial registration: Clinicaltrials.gov; NCT03702881, date of registration: October 11, 2018.