Nonsurgical correction of occlusal canting using temporary anchorage devices: A systematic review

Objective: The recent development of temporary anchorage devices (TADs) allows orthodontic canting correction by selective intrusion of the molars. The purpose of this study was to review the treatment strategy and outcomes after orthodontic correction of occlusal canting using the TADs based on published literature including the case reports. Materials and methods: A systematic review of published English-language human clinical studies was conducted by electronic search of PubMed, Embase & Medline, and Scopus reviews up to Dec 2023. For inclusion, reports required documentation of subject demographic characteristics; location or type of TADs; diagnosis; presence of maxillary occlusal canting (MOC); and treatment outcomes (MOC correction). Studies were excluded if they involved orthognathic surgery to correct MOC. Critical appraisal for all included studies were conducted with the case reports/case series appraisal checklist of the Joanna Briggs Institute (JBI). The current study was registered in PROSPERO (CRD42021226432). Results: The search identified 260 reports and a total of 33 case reports met inclusion criteria with 46 individual patient cases. The results reported that occlusal canting could be resolved by unilateral intrusion of maxillary posterior teeth using TADs. The reported the amount of maxillary molar intrusion ranged from 1 mm to 4.8 mm. However, there were fundamental limitations in study subjects, paucity of data regarding the long-term stability, lack of standardization in intrusion mechanics, and variations in TAD devices. Conclusions: Although the previous reports mentioned that orthodontic canting correction with TADs could avoid maxillary surgery or orthognathic surgery itself, it cannot be concluded that non-surgical correction of occlusal canting can be comparable to surgical treatment. Further comparative investigation between surgical and nonsurgical canting correction is needed to clarify whether orthodontic intrusion can be an alternative to surgical canting correction in terms of efficacy and stability.