A complete physical mapping of the vitamin D receptor gene for dental implant loss: A pilot study.

OBJECTIVES: The aim of this pilot case-control study was to investigate the association of clinical variables and genetic polymorphisms in the vitamin D receptor gene (VDR) with dental implant loss. MATERIAL AND METHODS: This study was carried out with 244 individuals with mean age 51.90 ± 11.28 (81 cases and 163 controls matched by age, sex, and smoking habit). Also, the clusterization phenomenon was investigated stratifying the sample into two groups: (a) 34 patients with multiple losses (presenting two or more lost implants) and (b) 210 without multiple losses (up to one implant loss). Sociodemographic, clinical, and periodontal parameters were analyzed. The tagSNPs in the VDR gene were analyzed by real-time PCR. Univariate and multivariate analyses were performed (p < .05). RESULTS: Edentulism, number of implants installed, and Gingival, Plaque, and Calculus Indexes were associated with implant loss in the univariate analysis. After the multivariate analysis, the allele G of rs3782905 in the recessive model, together with number of installed implants and Gingival Index, was associated with implant failure. CONCLUSION: It is suggested that the allele G of rs3782905 in the recessive model may be a new genetic risk marker for dental implant loss in patients who lost two or more dental implants. In addition, number of implants installed and Gingival Index were also associated. Replication is mandatory to confirm these findings, due to the modest sample size of this work.

Analysis of the association of IL1B(C-511T) polymorphism with dental implant loss and the clusterization phenomenon.

OBJECTIVES: Endosteous dental implants consist in the treatment of choice to replace tooth loss. The knowledge that implant loss tends to cluster in subsets of individuals may indicate that host immune-inflammatory response is influenced by genetic factors. Interleukin-1 (IL-1) is a key mediator of inflammatory processes and functional polymorphisms in IL1 gene could be candidate genetic risk factors to study susceptibility to implant failure. The objective of this study was to investigate the association between IL1B (C-511T) genetic polymorphism and dental implant loss in a Brazilian population and its influence in the clusterization phenomenon. MATERIAL AND METHODS: The sample composed of 277 unrelated, both gender, mean age 53.63 ± 11.14 years individuals, divided into test group - 92 subjects with implant loss, and control group - 185 subjects with no implant loss. Patients' socioeconomic profile and clinical variables were investigated. Genomic DNA from oral mucosa was analyzed by polymerase chain reaction-restriction fragment length polymorphism. RESULTS: There was significant difference between the groups in medical treatment (P=0.040), edentulism (P=0.019), and mean number of placed implants (P=0.001). There was difference between groups with and without implant loss neither considering genotypes (P=0.279) nor alleles (P=0.168) for IL1B (C-511T) polymorphism. When individuals showing up to one implant failure (n=254) were investigated vs. patients presenting multiple implant loss (n=23), no difference was either observed between groups for genotype (P=0.083) and allele (P=0.838) frequencies. CONCLUSIONS: The borderline association of the study polymorphism with implant loss suggests further IL1 haplotype analysis to elucidate the global involvement of IL-1 proteins in the modulation of the osseointegration process.

Clinical aspects and polymorphisms in the LTA, TNFA, LTB genes and association with dental implant loss.

BACKGROUND: This study shows the relationship between host factors and environmental factors in the influence of susceptibility to loss of dental implants. PURPOSE: The aim of this study was to investigate the association of clinical aspects and tag SNPs of the genes LTA, TNFA, and LTB with dental implant loss. MATERIALS AND METHODS: The subjects consisted of 244 patients, divided into two groups: control group (C)-163 individuals who did not lose any implants, being in function for at least 6 months; and study group (S)-81 individuals who had lost at least one implant. DNA was collected from saliva, and the genotypes were determined by real time PCR. Univariate and multivariate analysis were employed p < .05. RESULTS: After multivariate analysis, dental implant loss remained associated with the presence of teeth (p = .011), a larger amount of placed implants (p = .001), and allelle C of rs2009658 of the LTA gene (p = .006). For the other tag SNPs of these studied genes, there was no association between the groups C and S with dental implants loss. CONCLUSION: Presence of teeth, number of placed implants and allele C of rs2009658 of LTA gene were associated with implant loss.

Lactotransferrin Gene (LTF) Polymorphisms and Dental Implant Loss: A Case-Control Association Study.

BACKGROUND: Dental implants have been widely used to replace missing teeth, accomplishing aesthetics and function. Due to its large use worldwide, the small percentage of implant loss becomes significant in number of cases. Lactotransferrin (LTF) is a pleiotropic protein, expressed in various body tissues and fluids, which modulates the host immune-inflammatory response and bone metabolism, and might be involved in dental implant osseointegration. Recently, a few studies have been investigating genetic aspects underlying dental implant failure. PURPOSE: This case-control study aimed to investigate the association of genetic markers (tag SNPs) in LTF gene and clinical parameters with dental implant loss. MATERIAL AND METHODS: 278 patients, both sexes, mean age 51 years old, divided into 184 without and 94 with implant loss, were genotyped for sixteen tag SNPs, representative of the whole LTF gene. Also, clinical oral and systemic parameters were analyzed. Univariate and Multivariate Logistic Regression model were used to analyze the results (p < .05). RESULTS: No association was found between the tag SNPs and implant loss in the study population. Clinical association was found with medical treatment, hormonal reposition, edentulism, number of placed implants, plaque, calculus, and mobility. CONCLUSION: Clinical variables, but not LTF gene polymorphisms, were associated with implant loss.