Stability of open-bite treatment in adult patients: A systematic review

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).

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.

Class II and anterior open bite malocclusion treated with mini-implants, intermaxillary elastics, speech therapy, and retained with a night-wear palatal crib wraparound

The teeth position in anterior open bite malocclusion depends on a balance of pressure between the tongue and lips and the treatment planning should include such variables. The objective of this study was to report an orthodontic case of an adult with maxillary protrusion and anterior open bite treated with skeletal anchorage and intermaxillary elastics. The patient presented a Class II malocclusion with anterior open bite, without a history of non-nutritive habits, and mandibular missing teeth at 54 years old. Mini-implants were inserted in the maxillary molars region to produce distal movement of the maxillary dentition while controlling molar extrusion, and in the mandibular anterior region on the left side to produce mesial movement of posterior teeth. Up and down intermaxillary elastics were worn in the area of the incisors to treat the open bite together with Class II intermaxillary elastics. Cleats were bonded in the lingual surface of the anterior teeth as spurs to the tongue posture. However, the best result on the anterior open bite treatment was coincident with the speech therapy. Normal relationships between the maxillary and mandibular occlusal plane of cusps, correct anterior overbite, and adequate proximal relationships were obtained at the end of treatment. The retention modality to the maxillary arch was daily wear of a removable standard wraparound and a night-time wraparound with the palatal crib. The new technology allows for more effective treatment in adults and speech therapy was helpful to achieve balanced pressure between the tongue and lips.

Stability of anterior open bite treatment with molar intrusion using skeletal anchorage: a systematic review and meta-analysis

OBJECTIVES

The aim of this systematic review and meta-analysis is to assess the degree of stability of anterior open bite (AOB) treatment performed through the molar intrusion supported with skeletal anchorage at least 1 year posttreatment.

METHODS

This study was registered in PROSPERO (CRD42016037513). A literature search was conducted to identify randomized (RCT) or non-randomized clinical trials based including those considering before and after design. Data sources were electronic databases including PubMed, Cochrane Library, Science Direct, Google Scholar, Scopus, Lilacs, OpenGrey, Web of Science, and ClinicalTrials.gov . The quality of evidence was assessed through the JBI tool and certainty of evidence was evaluated through the GRADE tool. Random effects meta-analysis was conducted when appropriate.

RESULTS

Six hundred twenty-four articles met the initial inclusion criteria. From these, only 6 remained. The mean posttreatment follow-up time was 2.5 years (SD = 1.04). The overbite showed a standardized mean relapse of - 1.23 mm (95% CI - 1.64, - 0.81, p < 0.0001). Maxillary and mandibular incisors presented a non-significant mean relapse, U1-PP - 0.04 mm (95% CI - 0.55, 0.48) and L1-MP - 0.10 mm (95% CI - 0.57, 0.37). Molar intrusion showed a relapse rate around 12% for the maxillary molars and a 27.2% for mandibular molars.

CONCLUSION

The stability of AOB through molar intrusion using TADs can be considered relatively similar to that reported to surgical approaches, since 10 to 30% of relapse occurs both in maxillary and mandibular molars. The level of certainty ranged between very low and low. RCTs reporting dropout during the follow-up are in dire need.