Tenting Screw–Assisted β-Tricalcium Phosphate Composite Grafting for Horizontal Alveolar Bone Augmentation in the Esthetic Zone

<title>Abstract</title> <p> <bold>Background</bold> Stable space maintenance and timely bone replacement are critical for horizontal alveolar bone augmentation in the anterior esthetic zone. β-Tricalcium phosphate (β-TCP) is an osteoconductive and biodegradable synthetic bone substitute with stable availability and relatively low cost. However, its limited space-maintaining capacity may restrict its use when applied alone. This study evaluated the clinical outcomes of a tenting screw-assisted β-TCP-based composite graft combined with concentrated growth factors and autogenous bone for horizontal alveolar bone augmentation in the anterior esthetic zone. <bold>Methods</bold> This retrospective study included 61 patients with horizontal bone deficiency in the anterior esthetic zone who underwent implant-supported rehabilitation at Fuyang People’s Hospital between January 2020 and September 2024, involving 80 implant sites. Digital surgical guides were used for implant placement, and simultaneous horizontal alveolar bone augmentation was performed at all deficient sites. Tenting screws were placed to maintain the regenerative space, followed by grafting with a β-TCP-based composite graft containing autogenous bone and CGF. The screws were removed 6 months after surgery. CBCT scans were obtained before surgery, immediately after surgery, and at 6, 12, and 18 months. Horizontal bone width was measured at 0, 2, and 4 mm apical to the implant platform. Pink and white esthetic outcomes were assessed at 18 months. <bold>Results</bold> Horizontal bone width at all measured levels was significantly greater immediately after surgery and at 6, 12, and 18 months after surgery than before surgery (P &lt; 0.01), indicating effective horizontal alveolar bone augmentation with this combined approach. No significant difference in augmented bone width was observed between the immediate postoperative and 6-month measurements (P &gt; 0.05), suggesting stable maintenance of the augmented space during early healing under the support of the tenting screws. At 12 months, augmented bone width showed a slight but statistically significant reduction compared with that at 6 months (P &lt; 0.01). This change may reflect graft-site remodeling after tenting screw removal, although the overall extent of bone resorption was limited. No significant difference was observed between 12 and 18 months (P &gt; 0.05), indicating that graft-site remodeling tended to stabilize after 12 months. Pink and white esthetic outcomes at 18 months were satisfactory. No tenting screw exposure occurred during follow-up, although mucosal translucency over the screw-head region was observed in two patients with a thin gingival phenotype. <bold>Conclusion</bold> The tenting screw space-maintenance technique combined with a β-TCP-based composite graft containing autogenous bone and CGF was associated with satisfactory horizontal alveolar bone augmentation in patients with horizontal bone deficiency in the anterior esthetic zone. This approach is technically practical and may represent a clinically feasible option for implant-supported rehabilitation in such patients. </p>