Work

The effect of varying the position of implant screw access opening on the stress distribution of sealing composite resin: a 3D-FEA study

Year: 2026

Type: article

Abstract: BACKGROUND: The aim of this study was to assess the mechanical differences of composite resin sealing the screw access channel with different-positioned openings by a three-dimensional finite element analysis. METHODS: A 3D finite element model of dental implant at the site of mandibular first molar was established using computer-aided design (CAD). Models of sealing composite resin with different thicknesses were applied under 200 N static loading, and the optimal thickness was then selected via stress distribution analysis of composite resin models. Angulated screw channel (ASC) was used to vary the position of implant screw access opening. 200 N static loading was then applied to composite resin models with the selected thickness at different stages of a chewing cycle, and the stress of sealing composite resin in screw access channel with different-positioned openings was compared. RESULTS: The stress within composite resin model was stably at a lower level when the thickness was no less than 3 mm. Varying the position of implant screw access opening influenced stress distribution of sealing composite resin. In contrast with the opening located at central fossa, both maximum von Mises stress and shear stress of sealing composite resin (4.503 MPa and 1.032 MPa) was reduced when the opening was on the lingual side of central fossa (3.974 MPa and 0.9464 MPa) but was increased when the opening was on the buccal side of central fossa (5.695 MPa and 2.162 MPa). CONCLUSIONS: The stress was significantly lower at the site of mandibular molar when the position of screw access opening was designed on the lingual side of central fossa. Within the limits of the present in silico investigation, this study provided a new design strategy for screw-retained implant prosthesis to reduce the mechanical complications caused by the incomplete sealing of screw access opening.

Source: BMC Oral Health

DOI: 10.1186/s12903-026-07696-x

Authors: Feifan Li, Meiqi Wu, Xiya Zhang, Mengfei Bi, Ming Shen, Zhixuan Zhou

Institution: Nanjing Medical University

Language: English

Topic: Dental Implant Techniques and Outcomes

Subfield: Oral Surgery

Field: Dentistry

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $3,190