Objective: To compare the treatment effects of five bone-anchored maxillary protraction protocols (BAC3E, BAMP, BARME-FM, BARME-ME, SAFM) for skeletal Class III malocclusion. Methods:We conducted a systematic literature search through CENTRAL, EBSCO, PubMed and Web of Science and included the randomized controlled trials and clinical controlled trials, which met the criteria. A Bayesian network meta-analysis (NMA) for SNA, SNB, ANB, SN-MP and Wits appraisal was performed in R software using a random consistency model. The additional analyses included node-splitting analysis, statistical heterogeneity analysis, sensitivity analysis and ranking probability by SUCRA.Results: A total of 598 articles were initially obtained; 13 articles involving 482 individuals were eventually included. Among the five bone-anchored maxillary protraction protocols, the largest increment in SNA and Wits appraisal was observed in the BAMP group and BAC3E group, respectively; the SAFM, BAC3E and BAMP groups showed similar capability in terms of changes of ANB; least clockwise rotation of the mandible was found in the BARME-ME group, followed by the BAMP group; dental compensation appears to be most pronounced in the BAC3E group; and intermaxillary traction seems to reduce the lingual inclination of lower incisors and even cause labial inclination. Conclusions:The SAFM, BAMP and BAC3E groups seem to be advantageous in the improvement of the maxillo-mandibular relationship, followed by the BARME-FM and BARME-ME groups. The findings of this study should be interpreted with caution as only short-term effects were compared and the quality of evidence ranged from very low to moderate. More RCTs with high-quality and long-term investigation are needed.

Temporomandibular joint (TMJ) osteoarthritis causes fibrocartilage damage to the TMJ disc and mandibular condyle, resulting in local pain and functional impairment that further reduces patients’ quality of life. Tissue engineering offers a potential treatment for fibrocartilage regeneration of the TMJ disc and mandibular condyle. However, the heterogeneous structure of TMJ fibrocartilage tissue poses significant challenges for the fabrication of biomimetic scaffolds. Over the past two decades, some researchers have attempted to adopt three-dimensional (3D) printing techniques to fabricate biomimetic scaffolds for TMJ fibrocartilage regeneration, but publications on such attempts are limited and rarely report satisfactory results, indicating an urgent need for further development. This review outlines several popular 3D printing techniques and the significant elements of tissue-engineered scaffolds: seed cells, scaffold materials, and bioactive factors. Current research progress on 3D-printed scaffolds for fibrocartilage regeneration of the TMJ disc and mandibular condyle is reviewed. The current challenges in TMJ tissue engineering are mentioned along with some emerging tissue-engineering strategies, such as machine learning, stimuli-responsive delivery systems, and extracellular vesicles, which are considered as potential approaches to improve the performance of 3D-printed scaffolds for TMJ fibrocartilage regeneration. This review is expected to inspire the further development of 3D printing techniques for TMJ fibrocartilage regeneration.