AlMagaleh, W. R., A. A. Swelem, and I. A. W. Radi, "The effect of 2 versus 4 implants on implant stability in mandibular overdentures: A randomized controlled trial.", The Journal of prosthetic dentistry, vol. 118, issue 6, pp. 725-731, 2017 Dec. Abstract

STATEMENT OF PROBLEM: Dental research is rich with articles that investigated the influence of host-site variables, some implant-related variables (implant length, diameter, taper, design, location, and surface topography), different loading protocols or surgical procedures, and measurement methodology on dental implant stability. However, the number of implants and its effect on implant stability remain unclear.

PURPOSE: The purpose of this randomized clinical trial was to investigate the influence of implant number on implant stability by comparing 2 versus 4 implants in mandibular implant overdentures.

MATERIAL AND METHODS: The trial included 20 participants with edentulous mandibular ridges. Participants were randomly assigned to 2 equal groups, a 4-implant (experimental) group consisting of 4 implants installed in lateral-canine and premolar regions; and a 2-implant (control) group, consisting of 2 implants in lateral-canine regions. Implant stability was measured using resonance frequency analysis at implant placement and then at 1, 3, 6, 9, and 12 months. The Student t test was used to compare the implant stability quotient (ISQ) values of the anterior implants in the 4-implant and 2-implant groups. One-way ANOVA followed by the post hoc Bonferroni test was used to compare ISQ values among the different follow-up periods within each group (α=.05).

RESULTS: Mean ISQ values for anterior implants in the 4-implant group were slightly higher than those recorded for the 2-implant group at all follow-up periods. However, these differences were not statistically significant (P>.05). Within-group comparison revealed an initial decrease in implant stability for all implants. This decrease was statistically significant for the 2-implant group (P<.001) and for posterior implants in the 4-implant group (P<.001). This was then followed by a gradual increase in ISQ values for all implants in both groups.

CONCLUSIONS: Increasing the number of implants from 2 to 4 in mandibular implant overdentures did not have a significant influence on implant stability.

Abdelnabi, M. H., and A. A. Swelem, "Silicone versus acrylic resilient long term soft liners; a cross-over clinical study", Current Science International, vol. 9, issue 1, pp. 1 -11, 2020.
Abdelnabi, M. H., and A. A. Swelem, "Bite force, masticatory efficiency and patient satisfaction in patients with nonmetal clasp dentures: a randomized cross-over study", Current Science International, vol. 7, issue 4, pp. 641-649, 2018.
Metwally, A. F., and A. A. Swelem, "Comparative study between bone height changes around implants placed using stereolithographic versus conventional surgical guides", Egyptian Dental Journal, vol. 64, issue 4, pp. 1 -10, 2018.
Abdelnabi, M. H., and A. A. Swelem, "Digital Technology in Complete Denture Prosthodontics: A Review of literature", Egyptian Dental Journal, vol. 63, issue 3, pp. 1023-1037, 2017.
Swelem, A. A., and M. H. Abdelnabi, "Comparative study between faculty and student assessments of impressions made by undergraduates", Egyptian Dental Journal, vol. 62, issue 3, pp. 211-221, 2016.
Abdullrahman, A., A. A. Swelem, and N. Abbas, "The Effect of ozonated water, sodium hypochlorite and glutaraldehyde on candida albicans in complete denture wearers", Egyptian Dental Journal, vol. 61, pp. 683 -690, 2015.
Swelem, A. A., M. H. Abdelnabi, and M. Shehata, "Metallic denture bases and RPD frameworks: Past, Present and Future", Egyptian Dental Journal, vol. 60, pp. 3925 -3936, 2014.
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