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Published on: October 18, 2021
In situ onlay bone grafting in the anterior maxilla: a retrospective study comparing two surgical techniques with a
Xiaofu Yang1,2, Miao Sun1, Cheng Shu1
1School of StomatologyZhejiang Provincial Clinical Research Center for Oral DiseasesEngineering Research Center of Oral Biomaterials and Devices of Zhejiang Province, Stomatology HospitalZhejiang University School of MedicineKey Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Hangzhou, 310000, China.
Background:
Autologous bone grafting is considered as "gold standard" in the alveolar ridge augmentation techniques. In situ onlay grafting uses grafts adjacent to edentulous sites without a separate donor site. Several studies have revealed the satisfactory short-term performance of this less invasive modified technique, but no information is available of stability of alveolar ridge reconstructed by in situ onlay grafting and implant performance after occlusal loading in a mid-term follow-up. This study is to retrospectively evaluate the radiographic and patient reported outcomes (PROMs) of a modified onlay grafting technique and the subsequent implantation in anterior maxilla using in situ grafts without a second bone harvesting region.
Methods:
A total of 83 patients contributed 119 edentulous deficiency sites, and 104 implants were placed in anterior maxilla. 44 patients received in situ onlay grafting using subnasal grafts and 39 patients received ex situ onlay grafting using mandibular symphysis grafts. Alveolar ridge height and multileveled widths were assessed using cone-beam computed tomography (CBCT) prior grafting and at five subsequent time points. Clinical parameters and PROMs were evaluated with a visual analog scale (VAS) during the follow-up. Approximately 6 months after onlay grafting, dental implants were placed followed by fixed prosthetic rehabilitation. Implant survival and success rates were assessed with a mean follow-up of 42.90 months.
Results:
The horizontal bone resorption at cervical level after 1-year occlusal loading of in situ group (1.73% ± 1.29%) was lower than that of ex situ (3.85% ± 1.50%) group (P = 0.04). No other significant difference regarding bone resorption was found. The patient reported pain scores at 7 days after surgery of in situ group (2.43 ± 1.17) was lower than that of ex situ group (3.47 ± 2.08, P = 0.02). No implant loss was observed. The implant success rates were 96.36% in in-situ group and 97.96% in ex-situ group.
Conclusions:
Within the limitations of the present retrospective study, the findings suggest that in situ onlay grafting may be a promising approach for reconstructing the anterior maxillary alveolar ridge and facilitating subsequent implant placement. These preliminary results are hypothesis-generating and warrant further validation through prospective, long-term investigations.
Trial Registration:
This study was retrospectively registered in Chinese Clinical Trial Registry (Registration number: ChiCTR2400083954, Registration date: 2024-05-08).
