Yaghobee S, et al. J Korean Assoc Oral Maxillofac Surg. 2014 Oct;40(5):220-224. https://doi.org/10.5125/jkaoms.2014.40.5.220

Periodontal disease (PD) and peri-implantitis (PI) are characterized by an immune response leading to destructive inflammation. The prominent impact of genetic factors on periodontitis has been previously evaluated and IL-17 has found to play a critical role in this process. This cytokine has a controversial behavior. This study aimed at finding out whether the polymorphism of this cytokine plays a significant role in chronic periodontitis (CP) and PI or it is just a pro-inflammatory regulatory cytokine. Fresh human blood samples were obtained and three main genotypes were traced carefully. The samples were transferred into 96-well plates and sent to KBioscience Institute in the United Kingdom for genotyping the polymorphism using Competitive Allele Specific PCR (KASP) technique. SPSS version19 software and chi-square and Kruskal-Wallis tests were used for statistical differences considering p-value less than 0.05. A significant difference was detected between the three groups in terms of specific SNP studied in this experiment (P = 0.00). The CC genotype of IL17 polymorphism (rs10484879) may contribute to the pathogenesis of peri-implantitis and periodontitis. The association of IL-17 polymorphism with PI and CP is a promising finding that may help in future similar studies on other ethnicities and larger study populations.

The aim of this study was to assess stress and strain patterns in cortical and cancellous bones surrounding newly designed dental implants with different thread patterns. Static loading of dental implants has been well studied, but studies on dynamic loading and fatigue analysis of dental implants are scarce. This study analyzed the static, dynamic, and fatigue behaviors of dental implants using finite element analysis (FEA). Two models of dental implants were analyzed in this study. Model A was a tapered implant with V-shaped threads and model B was a tapered implant with microthreads in the uppermost region and V-shaped threads in the rest of the body. Two types of loading conditions were simulated in an FEA model and stress and strain patterns in the surrounding bone were analyzed. Dynamic loading increased the level of stress by 5–10% compared with static loading. Both implants showed acceptable results under static and dynamic loadings, but the second implant with microthreads caused lower stress and strain in cortical and cancellous bones. Dynamic and fatigue analyses can provide a more realistic understanding of the function of dental implants. Replacing the uppermost threads with microthreads can lead to more desirable stress patterns in bone, as well as a higher safety factor and longevity.