Acoustic resonance frequency analysis for evaluating prosthetic screw stability in splinted implant-supported fixed dental prostheses: An in vitro study

Jiaer Guo; Xiaolu Wang; Zhixin Liu; Jianying Zhou; Lin Wang

doi:10.1016/j.prosdent.2024.10.028

Acoustic resonance frequency analysis for evaluating prosthetic screw stability in splinted implant-supported fixed dental prostheses: An in vitro study

J Prosthet Dent. 2024 Nov 15:S0022-3913(24)00723-6. doi: 10.1016/j.prosdent.2024.10.028. Online ahead of print.

Authors

Jiaer Guo¹, Xiaolu Wang², Zhixin Liu¹, Jianying Zhou³, Lin Wang⁴

Affiliations

¹ Resident, Department of Oral Implantology, Hospital of Stomatology, Guanghua School of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, PR China.
² Doctoral student, Key Laboratory of Sensing Technology and Biomedical Instrument of Guangdong Province, School of Biomedical Engineering, Sun Yat-sen University, Guangzhou, PR China.
³ Professor, State Key Laboratory of Optoelectronic Materials & Technology, School of Physics, Sun Yat-sen University, Guangzhou, PR China.
⁴ Associate Professor, Department of Oral Implantology, Hospital of Stomatology, Guanghua School of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, PR China. Electronic address: [email protected].

PMID: 39550228
DOI: 10.1016/j.prosdent.2024.10.028

Abstract

Statement of problem: Prosthetic screw loosening is a common mechanical complication of implant-supported fixed dental prostheses. Although techniques for detecting screw loosening in single implant-supported fixed dental prostheses have been reported, studies on the screw stability for splinted implant-supported fixed dental prostheses are lacking.

Purpose: The purpose of this in vitro study was to determine whether acoustic resonance frequency analysis using a newly developed system could detect prosthetic screw loosening in splinted implant-supported fixed dental prostheses.

Material and methods: Maxillary and mandibular edentulous gypsum casts with screw-retained definitive fixed dental prostheses supported by 6 implants were used. A tapping simulation (0.2 N, 50 Hz) was directly applied to the buccal side of the tested screw, and a pickup device was used to collect the acoustic signals. The resonance peak frequencies of these signals were extracted by using time-frequency-domain analysis based on short-time Fourier transform. A 2-way mixed analysis of variance was performed to evaluate how jaw position and insertion torque affect resonance peak frequency. The Pearson correlation analysis was used to assess the relationship between the insertion torque and resonance peak frequency for each screw (α=.05).

Results: Deviation from the insertion torque resulted in significant changes in the resonance peak frequency within 6 to 9 kHz. Additionally, significant positive correlation between the insertion torques and resonance peak frequencies was observed for all screws (P<.05). This correlation was affected by the position of the screw within the prosthesis. Specifically, screw loosening in the posterior and anterior regions had a greater influence on the resonance peak frequency than that in the central region.

Conclusions: The acoustic resonance peak frequency shifted leftward as the screw preload torque decreased, indicating a significant correlation with screw stability. These results suggest that acoustic resonance frequency analysis can be used to detect the stability status of a single prosthetic screw in a splinted implant-supported fixed dental prosthesis conveniently and with high sensitivity.