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. 2023 Sep 11;16(1):203.
doi: 10.1186/s13104-023-06486-w.

Retrospective digital study of mandibular flexure in patients with long-span fixed restorations supported by natural teeth

Hussein El Charkawi  1 , Hossam I Nassar  1 , Medhat Sameh Abdelaziz  2
Affiliations

Retrospective digital study of mandibular flexure in patients with long-span fixed restorations supported by natural teeth

Hussein El Charkawi et al. BMC Res Notes. .

Abstract

Purpose: This retrospective study aims to evaluate the mandibular flexure on a long-span rigid fixed prosthesis supported by natural teeth.

Materials and methods: Nine patients (five males and four females) were included in this study who had long-span rigid mandibular fixed prostheses for long-term (10-15 years) that have led to radiographic changes around the supporting teeth. The mandibular flexure was measured digitally after adhering reference markers to the prostheses. Intraoral scans were obtained at the minimum and maximum mouth openings before and after splitting the preexisting prostheses. The distances between the markers were measured, and mandibular flexure was calculated.

Results: This study showed a significant deviation (narrowing) of the mandible before and after splitting the rigid fixed prostheses (P value < 0.05).

Conclusion: Digital analysis of the data collected from the patients in this retrospective study indicated that deviations occur during mandibular flexure.

Clinical relevance: Splitting the full arch prosthesis could prevent the negative consequences of mandibular flexure on restorations. Trial registration The study was registered on clinicaltrials.gov with registration number NCT05617274 (15/11/2022).

Keywords: Digital analysis; Long-span fixed prosthesis; Mandibular flexure.

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Conflict of interest statement

The authors declare that they have no competing interests.

Figures

Fig. 1
Fig. 1
Panoramic X-ray showing bone loss around the natural teeth for a patient having long-span fixed prosthesis
Fig. 2
Fig. 2
Panoramic X-ray showing bone loss around the posterior teeth for a patient having long-span fixed prosthesis
Fig. 3
Fig. 3
Intra-oral scanning of long-span fixed prosthesis with reference markers bonded to the prosthesis
Fig. 4
Fig. 4
Intra-oral scanning after splitting of the wide span fixed prosthesis with reference markers bonded to the prosthesis
Fig. 5
Fig. 5
Distance measurement in mm between the reference markers in long- span fixed prosthesis
Fig. 6
Fig. 6
Bar chart of mean mandibular flexure before and after splitting of long-span fixed prosthesis
See this image and copyright information in PMC

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