Statement of problem
Screw loosening is a common problem in implant dentistry; however, information is sparse on the influence of different fluids on the screw threads.
The purpose of this in vitro study was to investigate the influence of 4 different fluids and agents (saliva, blood, chlorhexidine [CHX] gel, and special sealing silicone) on the preload force of abutment screws.
Materials and methods
The test specimens (N=50) consisted of a thread sleeve resembling the implant, an abutment analog, and an abutment screw. The tightening of the screw with a torque wrench was performed in 5 steps (15 Ncm, 20 Ncm, 25 Ncm, 30 Ncm, and 35 Ncm). Each agent was applied in the lumen of the thread sleeve of 10 specimens. Ten dry thread sleeves served as the control. Comparisons between 2 independent groups were performed with the t test or Wilcoxon–Mann–Whitney test, as appropriate. The Bonferroni correction was used for multiple comparisons (α=.05).
Preload forces increased linearly with the applied tightening torque for dry implant lumina, as well as for saliva, blood, silicone, and CHX gel in the implant lumina or thread sleeves. In general, none of the tested agents resulted in significantly higher preload forces compared with the dry control.
The agents investigated did not have any lubricant action on implant abutment screws.
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- Biological and mechanical complications of angulated abutments connected to fixed dental prostheses. A systematic review with meta-analysis.J Oral Rehabil. 2020; 47: 101-111
- Loosening of the fixing screw in single implant crowns: predisposing factors, prevention and treatment options.J Esthet Restor Dent. 2017; 29: 233-246
- Cement-retained versus screw-retained implant restorations: achieving optimal occlusion and esthetics in implant dentistry.J Prosthet Dent. 1997; 77: 28-35
- A comparison between screw- and cement-retained implant prostheses. A literature review.J Oral Implantol. 2012; 38: 298-307
- Retrievable cemented implant restorations.J Prosthodont. 1998; 7: 120-125
- Simple device for locating the abutment screw position of a cement-retained implant restoration.J Prosthet Dent. 2013; 109: 272-274
- A technique for repairing a loosening abutment screw for a cement-retained implant prosthesis.J Prosthodont. 2011; 20: 652-655
- Intra-operative application of chlorhexidine gel reduces bacterial counts in internal implant cavity.Eur J Oral Sci. 2015; 123: 425-431
- Microbiological and biochemical effectiveness of an antiseptic gel on the bacterial contamination of the inner space of dental implants: a 3-month human longitudinal study.Int J Immunopathol Pharmacol. 2009; 22: 1019-1026
- Internal decontamination of dental implants: an in vivo randomized microbiologic 6-month trial on the effects of a chlorhexidine gel.J Periodontol. 2008; 79: 1419-1425
- Transfer of bacteria into the internal cavity of dental implants after application of disinfectant or sealant agents in vitro.Int J Oral Maxillofac Implants. 2016; 31: 563-570
- In vitro sealing ability of two materials at five different implant-abutment surfaces.J Periodontol. 2006; 77: 1828-1832
- Implant screw mechanics.Dent Clin North Am. 1998; 42: 71-89
- Geometric comparison of five interchangeable implant prosthetic retaining screws.J Prosthet Dent. 1995; 74: 373-379
Fini S, De Agostinis M, Croccolo D, Olmi G, Paiardini L, Robusto F. Residual shank torque of bolted joints: a numerical investigation. In: Volume 2: computer technology and bolted joints. San Antonio, Texas: ASME; 2019:V002T02A040. Available at: https://doi.org/10.1115/PVP2019-94067.
- Influence of lubricant on screw preload and stresses in a finite element model for a dental implant.J Prosthet Dent. 2014; 112: 340-348
- Effects of screw configuration on the preload force of implant-abutment screws.Int J Oral Maxillofac Implants. 2018; 33: 25-32
Published online: September 20, 2020
© 2020 by the Editorial Council for The Journal of Prosthetic Dentistry.