Genome-wide association study of stage III/IV grade C periodontitis (former aggressive periodontitis) in a Spanish population

AIM

To identify loci associated with stages III/IV, grade C periodontitis (PIII/IV-C) through a genome-wide association study (GWAS).

MATERIALS AND METHODS

441 Caucasian Spanish PIII/IV-C cases from the SEPA Network of Research Clinics and 1141 controls from the Banco Nacional de ADN were genotyped with "Axiom Spain Biobank Array," which contains 757836 markers, including rare and low-frequency Spanish variants. The analysis of the individual association and subsequently the gene-level analysis with Sequence Kernel Association Test (SKAT) were carried out adjusting for age, sex and PC1 covariates. Pathway Analysis was additionally performed with Ingenuity Pathway Analysis (IPA) software on the top associated genes.

RESULTS

In the individual analyses, no genome-wide significant signals were detected. However, 8 SNPs of 8 loci reached suggestive evidence of association with PIII/IV-C, including FAT3 rs35709256, CSNK1G2 rs4807188, MYH13 rs2074872, CNTN2 rs116611488, ANTXR1 rs4854545, 8p23.2 rs78672540, ANGPT1 rs13439823 and PLEC rs11993287 (p < 5 × 10^-6 ). SKAT analysis identified other interesting signals at CNTN2, FBXO44, AP1M2, RSPO4, KRI1, BPIFB1 and INMT, although their probability does not exceed the multiple-test correction. IPA indicated significant enrichment of pathways related to cAMP, IL-2, CD28, VDR/RXR and PI3K/Akt.  CONCLUSIONS: GWAS found no SNPs significantly associated with PIII/IV-C.

Tooth Fractures in Fixed Full-Arch Implant-Supported Acrylic Resin Prostheses: A Retrospective Clinical Study

PURPOSE

The aim of this study was to assess the influence of several variables in the frequency of prosthetic teeth fractures in fixed full-arch implant-supported acrylic resin prostheses.

MATERIALS AND METHODS

The influence of each variable was determined after analyzing the results obtained from 161 prostheses after a mean follow-up period of 39.69 months. All patients were treated with standard Nobel Biocare and Biomet 3i implants, and followed a strict prosthodontic protocol.

RESULTS

A total of 155 fractures were recorded, all of which took place in 60 prostheses (40% of the total). Statistically significant differences were found among several variables: the arch the prosthesis was on, patient sex, opposing arch characteristics, length of the cantilevers, and whether the structure had mechanical retention. The prostheses that suffered a greater number of fractures were those that had been placed in men, opposing a natural arch, with cantilevers shorter than 10 mm and without mechanical retention. Patient age and presence or absence of a cantilever were not determinants.

CONCLUSION

Tooth fractures in fixed full-arch implant-supported metal-acrylic prostheses are a common complication. Several factors are linked more directly with the need for mechanical maintenance. The design and indications of this type of prosthesis should be carefully considered.