Correlation between Inflammasomes and Microbiota in Peri-Implantitis.

The activation of inflammasomes is thought to induce the inflammatory process around dental implants. No information is available on the correlation between microbiota and inflammasomes in clinical samples from patients suffering peri-implantitis. For this cross-sectional study, 30 biofilm samples were obtained from 19 patients undergoing surgical treatment for peri-implantitis because of the presence of bleeding on probing, probing depth higher than 6 mm, and radiographic bone loss higher than 3 mm. Then, soft tissue samples from around the implant were also collected. The relative abundance of bacteria and alpha-diversity indexes were calculated after analyzing the 16S rRNA gene using next-generation sequencing. The soft-tissue samples were processed for evaluation of the inflammasomes NLRP3 and AIM2 as well as caspase-1 and IL-1ß. The relative abundance (mean (SD)) of specific species indicated that the most abundant species were Porphyromonas gingivalis (10.95 (14.17)%), Fusobacterium vincentii (10.93 (13.18)%), Porphyromonas endodontalis (5.89 (7.23)%), Prevotella oris (3.88 (4.94)%), Treponema denticola (2.91 (3.19)%), and Tannerella forsythia (2.84 (4.15)%). Several correlations were found between the species and the immunohistochemical detection of the inflammasomes NLRP3 and AIM2 as well as caspase-1 and IL-1ß, both in the epithelium and the lamina propria. A network analysis found an important cluster of variables formed by NLRP3 in the lamina propria and AIM2, caspase-1, and IL-1ß in the lamina propria and the epithelium with Prevotella dentalis, Prevotella tannerae, Tannerella forsythia, or Selenomonas timonae. Thus, it could be concluded that inflammasomes NLRP3 and AIM2 and their downstream effectors caspase-1 and interleukin-1ß can be significantly associated with specific bacteria.

Inflammasomes NLRP3 and AIM2 in peri-implantitis: A cross-sectional study.

BACKGROUND: Inflammasome components NLRP3 and AIM2 contribute to inflammation development by the activation of caspase-1 and IL-1ß. They have not been yet evaluated in samples from patients with active peri-implantitis. Thus, the aim of the present study is to analyze the expression of inflammasomes NLRP3 and AIM2 and subsequent caspase 1 and IL-1ß assessing the microenvironment of leukocyte subsets in samples from patients with active peri-implantitis. METHODS: Biopsies were collected from 33 implants in 21 patients being treated for peri-implantitis. Biopsies from gingival tissues from 15 patients with healthy periodontium were also collected for control. These tissues were evaluated through conventional histological stainings. Then, immunohistochemical detection was performed to analyze NLRP3, AIM2, caspase-1, and IL-1ß and markers of different leukocyte subsets. PCR for inflammasomes and related genes was also done. RESULTS: This manuscript reveals a high immunohistochemical and mRNA expression of NLRP3 and AIM2 inflammasomes, caspase-1, and IL-1ß in biopsies collected from human peri-implantitis. The expression of the tested markers was significantly correlated with the increase in inflammatory infiltrate, probing depth, presence of biofilm, and bleeding on probing. In these peri-implantitis lesions, the area of biopsy tissue occupied by inflammatory infiltrate was intense while the area occupied by collagen was significantly lower. In comparison with periodontal healthy tissues, the inflammatory infiltrate was statistically significantly higher in the peri-implantitis biopsies and was mainly composed of plasma cells, followed by T and B lymphocytes. CONCLUSION: In human peri-implantitis, chronic inflammation can be explained in part by the action of IL-1ß/caspase 1 induced through NLRP3 and AIM2 inflammasome activation.

Concordancia inter-examinador en la evaluación de hallazgos periodontales mediante radiografías panorámicas / Inter-examiner concordance in the assessment of periodontal findings by means of panoramic X-rays

RESUMEN Objetivo Estimar el grado de concordancia inter-examinador en la interpretación de hallazgos periodontales en radiografías panorámicas en estudiantes de último año de la Facultad de Odontología de la Universidad de Cartagena. Material y métodos Se realizó un estudio descriptivo de concordancia-consistencia inter-observador para la interpretación de hallazgos periodontales en radiografías panorámicas entre estudiantes de último año de pregrado de la Facultad de Odontología de la Universidad de Cartagena, con relación a un especialista en periodoncia. La evaluación de la concordancia se realizó a través del coeficiente kappa utilizando SPSS Statistics 2.0. Resultados Se evaluaron a 80 estudiantes del último año de pregrado. Cada uno valoró dos radiografías panorámicas, para un total de 160 observaciones. La concordancia general estableció un valor de kappa mínimo de 0.011 y un valor máximo de 0.720. Conclusiones La concordancia entre los estudiantes observadores y el estándar de oro fue pobre. Lo que indica que los estudiantes no aplican los conocimientos obtenidos durante el pregrado de odontología, dando así una errónea impresión del estado periodonto.

ABSTRACT Objective To assess the degree of inter-examiner concordance in the interpretation of periodontal findings in panoramic X-rays in last year students of the School of Dentistry at the University of Colombia. Material and methods A descriptive inter-observer concordance-consistency study was conducted for interpretation of periodontal findings in panoramic X-rays among last year students of the School of Dentistry of the University of Colombia and compared results to thos obtained by a periodontics specialist. Concordance evaluation was achieved by means of a kappa coefficient using SPSS Statistics 2.0 program. Results 80 last year students (undergraduate seniors) were evaluated each one assessed two panoramic X-rays, for a total of 160 observations. General concordance established a minimum kappa value of 0.011, and maximum value of 0.720. Conclusions Concordance among observing students and the gold standard was poor. This indicated that students did not apply acquired knowledge during their undergraduate dental studies, and provided thus a misleading impression on the circumstances of the periodontium.