Tenting effect of dental implant on maxillary sinus lift without grafting

Background/purpose: Maxillary sinus lift without grafting is an alternative procedure that is used to lower the risk of infection and facilitate the surgical procedure. The objective of this study was to evaluate the tenting effect of the dental implant by measuring the amount and morphology of bone formation around it. Material and methods: 49 implants were placed in 26 patients by maxillary sinus lift without grafting. Radiographic images were taken preoperatively and at 6 months postoperatively and used to evaluate the height of the residual bone, the width of the maxillary sinus, the amount of bone formation, and the adjacent tooth. Results: The most common type of bone formed around the implant, as seen in 23 cases, was the same height as the apex of the implant; in 11 cases, it was 0-2 mm above the apex of the implant, and in 7 cases, 2 mm or more. Meanwhile, 5 cases showed defects. The tent type of bone formation, which showed more bone formation at the implant apex than in the surrounding bone, was overwhelmingly the most common. (8 0.4%) The amount of bone formation increased in proportion to the difference between the residual bone height and the implant length. (P <.001). Conclusion: The amount of bone formation in the sinus lift without grafting increased in proportion to the length of the implants in the maxillary sinus due to the tenting effect of the implant in the maxillary sinus membrane. (c) 2020 Association for Dental Sciences of the Republic of China. Publishing services by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).