Metabolome and microbiome of chronic periapical periodontitis in permanent anterior teeth: a pilot study

Evaluation of a potential bidirectional influence of metabolic syndrome and apical periodontitis: An animal-based study

AIM

This study aimed to explore the possible bidirectional interrelations between fructose-induced metabolic syndrome (MS) and apical periodontitis (AP).

METHODOLOGY

Twenty-eight male Wistar rats were distributed into four groups (n = 7, per group): Control (C), AP, Fructose Consumption (FRUT) and Fructose Consumption and AP (FRUT+AP). The rats in groups C and AP received filtered water, while those in groups FRUT and FRUT+AP received a 20% fructose solution mixed with water to induce MS. The groups AP and FRUT+AP had the pulp of their right mandibular first molar exposed to induce AP. Food consumption, murinometric measurements, blood glucose levels and glucose tolerance were monitored. Fifty-six days after the start of the experiment, the animals were euthanized, and serum samples were collected for metabolomic analysis. Mandibles, livers and right kidneys were also collected. The area and volume of the periapical lesions were calculated using micro-computed tomography. Histopathological evaluation was performed. Kruskal-Wallis followed by the Student-Newman-Keuls or Mann-Whitney tests and one-way anova followed by Tukey's or Independent t-test were used for non-parametric and parametric data, respectively (p < .05). Multivariate analysis and variable importance in projection score were applied to assess metabolite profile differences among groups (p < .05).

RESULTS

FRUT and FRUT+AP groups showed significantly increased fluid intake, body mass, abdominal circumference, blood glucose levels, liver weight and visceral fat weight (p < .05), indicating the development of MS. The analyses of the metabolite profile suggest increasing glucose, histidine, lactate, fatty acid and phenylalanine in the FRUT+AP group. There were no significant differences in volume and area of periapical lesions in micro-CT analyses (p = .1048 and p = .7494, respectively). Histopathological analysis of the hemimandibles demonstrated areas of inflammatory response, necrosis and microabscess in the periapical region. Hepatic histopathological observations indicated notable differences in cell appearance, with the FRUT and FRUT+AP groups showing signs of microsteatosis. Kidney analysis revealed Bowman's space dilation in the FRUT and AP groups, while the FRUT+AP group exhibited retracted Bowman's space, suggesting a possible alteration in renal filtration capacity.

CONCLUSIONS

MS had no impact on the progression of AP in rats. However, AP exacerbated the systemic state affected by MS, with changes in liver and kidney tissues and metabolite levels.

Exploring the root canal microbiome in previously treated teeth: A comparative study of diversity and metabolic pathways across two geographical locations

AIM

To analyse and compare the root canal microbiome present in root-filled teeth of two different geographical populations, and to study their functional potential using a next-generation sequencing approach.

METHODOLOGY

Sequencing data obtained from surgical specimens from previously treated teeth with periapical bone loss from Spain and USA were included in the study. Taxa were classified using SILVA v.138 database. Differences in genera abundances among the 10 most abundant genera were evaluated using a Kruskal-Wallis test. Alpha diversity indices were calculated in mothur. The Shannon and Chao1 indices were used. Analyses of similarity (ANOSIM) to determine differences in community composition were done in mothur, with Bonferroni correction for multiple comparisons. p-Values < .05 were considered statistically significant. Identification of enriched bacteria function prediction in the study groups (KEGG pathways) was carried out by linear discriminant analysis effect size (LEfSe) via Python 3.7.6.

RESULTS

A greater alpha-diversity (Shannon and Chao1 indices) was observed from samples obtained in Spain (p = .002). Geography showed no significant effects on community composition via an ANOSIM using Bray-Curtis dissimilarities (R = 0.03, p = .21). Bacterial functional analysis prediction obtained by PICRUSt showed that 5.7% KEGG pathways differed between the Spain and US samples.

CONCLUSIONS

The taxonomic assessment alone does not fully capture the microbiome's differences from two different geographical locations. Carbohydrate and amino acid metabolism were enriched in samples from Spain, while samples from USA had a higher representation of pathways related to nitrogen, propanoate metabolism, and secretion systems.

Orthodontics and Endodontics Clinical Practice Correlation: A Narrative Review

Research on the connection between endodontic therapy and orthodontics is lacking. This overview of the literature synthesizes the findings from the fields of orthodontics and endodontics and explains how they are related. Beginning with the diagnosis, treating the patient at the appropriate time, moving endodontically treated teeth and traumatized teeth, resorbing roots by orthodontic mechanics, and managing traumatized teeth with orthodontic therapy. Multiple electronic databases were utilized including (PubMed, Scopus, Science Direct, and Web of Science) to perform manual literature searches. A total of 31 articles were reviewed and summarized in this paper in keywords like "Endodontically Treated Teeth and Orthodontic Treatment," "Endodontically Treated Tooth and Orthodontic Movement," "Orthodontic Treatment in RCT Teeth," "Root Canal Treatment with Orthodontic Movement," "Trauma with Orthodontic Movement," "Orthodontic and Endodontic." Orthodontic treatment of endodontically treated and traumatized teeth is a subject of controversy. The lack of research on the topic makes it a hard decision to make when to treat these teeth. Especially given that both orthodontic and endodontic treatments have multiple consequences on each other's outcomes. Thus, it is crucial for clinicians to understand how they integrate and have a guideline to refer to during decision-making. Successful orthodontic tooth movement could be carried out immediately after endodontic treatment. However, traumatized teeth need a follow-up period before initiating orthodontic movement, which ranges from three months to 12 months depending on the type of trauma and severity. Careful radiographic and clinical follow-up should be done during the healing period. Collaborative teamwork is important between orthodontists and endodontists for the success of treatment, and to achieve satisfactory outcomes.

"Magnet" Based on Activated Silver Nanoparticles Adsorbed Bacteria to Predict Refractory Apical Periodontitis Via Surface-Enhanced Raman Scattering

Refractory apical periodontitis (RAP) is an endodontic apical inflammatory disease caused by Enterococcus faecalis (E. faecalis). Bacterial detection using surface-enhanced Raman scattering (SERS) technology is a hot research topic, but the specific and direct detection of oral bacteria is a challenge, especially in real clinical samples. In this paper, we develop a novel SERS-based green platform for label-free detection of oral bacteria. The platform was built on silver nanoparticles with a two-step enhancement way using NaBH4 and sodium (Na+) to form "hot spots," which resulted in an enhanced SERS fingerprint of E. faecalis with fast, quantitative, lower-limit, reproducibility, and stability. In combination with machine learning, four different oral bacteria (E. faecalis, Porphyromonas gingivalis, Streptococcus mutans, and Escherichia coli) could be intelligently distinguished. The unlabeled detection method emphasized the specificity of E. faecalis in simulated saliva, serum, and even real samples from patients with clinical root periapical disease. In addition, the assay has been shown to be environmentally friendly and without secondary contamination through antimicrobial assays. The proposed label-free, rapid, safe, and green SERS detection strategy for oral bacteria provided an innovative solution for the early diagnosis and prevention of RAP and other perioral diseases.

Identification of disease-associate variants of aggressive periodontitis using genome-wide association studies

Aggressive periodontitis (AgP), Stage III or IV and Grade C according to the new periodontitis classification, is characterized by the rapid destruction of periodontal tissues in the systemically healthy population and often causes premature tooth loss. The presence of familial aggregation suggests the involvement of genetic factors in the pathogenesis. However, the genes associated with the onset and progression of the disease and details of its pathogenesis have not yet been fully identified. In recent years, the genome-wide approach (GWAS), a comprehensive genome analysis method using bioinformatics, has been used to search for disease-related genes, and the results have been applied in genomic medicine for various diseases, such as cancer. In this review, we discuss GWAS in the context of AgP. First, we introduce the relationship between single-nucleotide polymorphisms (SNPs) and susceptibility to diseases and how GWAS is useful for searching disease-related SNPs. Furthermore, we summarize the recent findings of disease-related genes using GWAS on AgP inside and outside Japan and a possible mechanism of the pathogenesis of AgP based on available literature and our research findings. These findings will lead to advancements in the prevention, prognosis, and treatment of AgP.

The prognostic prediction of periodontal non-surgery therapy in periodontitis patients based on surface-enhanced Raman measurements of pre-treatment saliva

Periodontitis is one of the most prevalent dental diseases, and the patients with periodontitis often suffer from refractory periodontitis or recurrence of disease due to improper or inadequate treatment. In clinical practice, the early and accurate assessment of post-treatment prognosis in periodontitis patients is always very important in order to implement timely interventions. In this study, a pre-treatment saliva SERS based prognostic protocol was explored to predict the prognosis of periodontal non-surgery therapy in periodontitis patients. According to the biomolecular analysis, significant differences in the levels of ascorbic acid, uric acid and glutathione are observed between good prognosis group and poor prognosis group, which are expected to serve as potential prognostic markers. Furthermore, high accuracy, sensitivity and specificity can also be achieved by using the proposed prognostic model. The excellent performance of the proposed method has demonstrated its potential for fast, accurate, and non-invasive prognostic prediction of periodontal non-surgery therapy in periodontitis patients, even at the time before implementing treatment, thus is expected to benefit timely and rational guidance on clinical interventions.