Journal of IMAB - Annual Proceeding (Scientific Papers)
Publisher: Peytchinski, Gospodin Iliev
ISSN: 1312-773X (Online)
Issue: 2017, vol. 23, issue 1
Subject Area: Dental Medicine
DOI: 10.5272/jimab.2017231.1505
Published online: 28 March 2017

Original Article

J of IMAB 2017 Jan-Mar;23(1):1505-1509
Dimitar Kirov1ORCID logoCorresponding Autor, Biser Stoichkov2ORCID logo,
1) Department of Prosthetic Dentistry, Faculty of Dental Medicine, Medical University, Sofia, Bulgaria.
2) Department of Oral and Maxillo-Facial Surgery, Faculty of Dental Medicine, Medical University - Sofia, Bulgaria.

Aim of the study: To establish the influence of various factors upon the loosening of abutment screw.
Material and Methods: The current study has analyzed the factors leading to loosening of the abutment screws implant-supported restorations. 116 patients have been examined with 234 setting implants for a period of 2 to 9 years. Factors related to the planning of implant prostheses such as area of implantation, available bone volume have been registered, as well as those related to the functional loading of dental implants. The impact of their effect has been calculated.
Results: Abutment screw loosening has been registered in 6.8% of the monitored cases. Regarding the type of connection between the implant and abutment a higher prevalence has been reported in connection with an internal octagon - 4.7% compared to the conical connection - 2.1%. It was found that the type of prosthesis, bruxism, cantilevers, non-balanced occlusion, crestal bone resorption and time of this complication setting in are factors of statistically significant influence.
Conclusion: It has been concluded that the optimal choice and number of implant positions, the design of prosthesis, achieving optimal occlusion as well as reporting cases of bruxism, leading to functional overload of dental implants are of particular importance in order to avoid bio-mechanical long-term complications.

Key words: abutment screw loosening, implant complications, occlusal load, bruxism, bone resorption,

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Please cite this article in PubMed Style or AMA (American Medical Association) Style:
Kirov D, Stoichkov B. Factors affecting the abutment screw loosening. J of IMAB. 2017 Jan-Mar;23(1):1505-1509. DOI: 10.5272/jimab.2017231.1505.

For correspondence: Dimitar Kirov, DDS, PhD, assistant professor, Department of Prosthetic Dentistry, Faculty of Dental Medicine, Medical University, Sofia; 1, Sv. Georgi Sofyiski St., 1431 Sofia, Bulgaria; E-mail:

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Received: 03 February 2017
Published online: 28 March 2017

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