Factors Influencing Bone Resorption after Augmentation Mentoplasty with Implants: A Retrospective Study Using Three-Dimensional Imaging.

[BACKGROUND] Augmentation mentoplasty with implants is an extremely rewarding procedure. Bone resorption is almost unavoidable. The high-risk factors for chin bone resorption have not been explored in the past. This study aimed to analyze and evaluate the factors influencing bone resorption after augmentation mentoplasty with implants using three-dimensional imaging.

[METHODS] We retrospectively analyzed preoperative craniofacial Computed Tomography scan data from 105 patients who underwent mandibular implantation surgery and 108 patients who did not. We also examined the extent to which different factors influenced the occurrence of bone resorption in the chin area.

[RESULTS] Patients with silicone gel implants are more prone to bone resorption than those with Medpor implants. Patients who experienced bone resorption had thicker mentalis muscles than those who did not experience bone resorption (6.35 ± 1. mm vs. 5.73 ± 1.25 mm, P < 0.05), and thinner cortical bone (3.25 ± 1.65 mm vs. 5.22 ± 2.04 mm, P < 0.05). Additionally, implants placed above the mandibular bone were more likely to induce bone resorption than those placed below it.

[CONCLUSIONS] This study is the first to systematically reveal the impact of implant type, placement position, mentalis muscle thickness, and cortical bone thickness on bone resorption after chin augmentation surgery. For patients with thicker mentalis muscles and thinner cortical bones, greater attention should be paid to the occurrence of bone resorption. Choosing silicone implants or placing the implants higher on the mandible can help reduce the occurrence of bone resorption. This study can assist clinicians in selecting appropriate treatment methods, thereby reducing post-implantation bone resorption.

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