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Aim: To investigate the influence of diabetes mellitus (DM) in a murine model of peri-implantitis (PI)., Materials and Methods: Twenty-seven 4-week-old C57BL/6J male mice had their first and second maxillary left molars extracted. Eight weeks later, one machined implant was placed in each mouse. Four weeks after osseointegration, the mice were divided into three groups: (a) control (C), (b) PI and (c) DM + PI. DM was induced by streptozotocin (STZ) administration. After DM induction, PI was induced using ligatures for 2 weeks. The hemimaxillae were collected for micro-CT and histological analyses. The primary outcomes consisted of linear (mm) and volumetric (mm 3 ) bone loss. Secondary outcomes were based on histological analysis and included inflammatory infiltrate, osteoclastic activity, matrix organization, composition and remodelling. Data are presented as means ± SEM. Statistical analyses were performed using one-way ANOVA, followed by Tukey's test., Results: Gingival tissue oedema was detected in the PI and DM + PI groups. Micro-CT showed significantly increased linear and volumetric bone loss in the DM + PI group compared to the C and PI groups. H&E staining showed greater inflammatory response and bone resorption in the PI and DM + PI groups than in the C group. The DM + PI group had significantly higher osteoclast numbers than the C and PI groups. Picrosirius red stained less for types I and III collagen in the PI and DM + PI groups than in the C group. There was a significant increase in monocyte/macrophage (CD-11b) counts and matrix metalloproteinases (MMP-2 and MMP-8) marker levels and a significant decrease in the matrix metalloproteinases inhibition marker (TIMP-2) levels in the DM + PI group compared to the C and PI groups., Conclusions: DM exacerbates PI-induced soft-tissue inflammation, matrix degradation and bone loss., (© 2024 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Considering the lack of consensus related to the impact of selective IL-6 receptor inhibition on bone remodeling and the scarcity of reports, especially on large bone defects, this study proposed to evaluate the biological impact of the selective inhibitor of interleukin-6 receptor (tocilizumab) in an experimental model of critical calvarial defect in rats. In this preclinical and in vivo study, 24 male Wistar rats were randomly divided into two groups (n=12/group): defect treated with collagen sponge (CG) and defect treated with collagen sponge associated with 2 mg/kg tocilizumab (TCZ). The defect in the parietal bone was created using an 8-mm diameter trephine drill. After 90 days, the animals were euthanized, and tissue samples (skull caps) were evaluated through micro-CT, histological, immunohistochemistry, cytokines, and RT-qPCR analyses. Tocilizumab reduced mononuclear inflammatory infiltration (P<0.05) and tumor necrosis factor (TNF)-α levels (P<0.01) and down-regulated tissue gene expression of BMP-2 (P<0.001), RUNX-2 (P<0.05), and interleukin (IL)-6 (P<0.05). Moreover, it promoted a stronger immunostaining of cathepsin and RANKL (P<0.05). Micro-CT and histological analyses revealed no impact on general bone formation (P>0.05). The bone cells (osteoblasts, osteoclasts, and osteocytes) in the defect area were similar in both groups (P>0.05). Tocilizumab reduced inflammatory cytokines, decreased osteogenic protein, and increased proteases in a critical bone defect in rats. Ninety days after the local application of tocilizumab in the cranial defect, we did not find a significant formation of bone tissue compared with a collagen sponge.

Dental implants are increasing in prevalence as desirable options for replacing missing teeth. Unfortunately, implants come with complications, and animal models are crucial to studying the pathophysiology of complications. Current murine model experiments can be lengthy, with 8 weeks of extraction socket healing before implant placement. Therefore, we aimed to investigate the efficacy of decreasing extraction healing time from 8 to 4 weeks in a dental implant mouse model. Thirty-one 3-week-old C57BL/6J male mice underwent maxillary first and second molar extractions followed by 8 (control) or 4 (test) weeks of extraction socket healing before implant placement. Mice were euthanized after 4 weeks of implant osseointegration. Samples were analyzed via microcomputerized tomography and histology. When mice received implants 4 weeks after extractions, there was no statistical difference in initial bone crest remodeling or surrounding bone volume compared to those after 8 weeks of healing. Histologically, the hard and soft tissues surrounding both groups of implants displayed similar alveolar bone levels, inflammatory infiltrate, osteoclast count, and collagen organization. A 4-week extraction healing period can be utilized without concern for osseointegration in a murine implant model and is a viable experimental alternative to the previous eight weeks of healing. While small animal implant models are less directly applicable to humans, advancements in experimental methods will ultimately benefit patients receiving dental implants through improved prevention and treatment of complications. Subsequent research could investigate occlusal effects or whether healing time affects prognosis after induction of peri-implantitis.

Aim: To identify Pseudomonas aeruginosa and Staphylococcus aureus in oral biofilms of intubated and non-intubated patients admitted to an Intensive Care Unit (ICU)., Methods: This was a cross-sectional study, with 30 biofilm sites sampled. S. aureus and P. aeruginosa were identified by conventional biochemical assays. Antimicrobial susceptibility was tested by disk-diffusion., Results: Of 30 sites, 50% contained P. aeruginosa and 3.33% S. aureus. P. aeruginosa was detected in similar amounts in all 3 sample sites, with 5 colonized sites (50%). S. aureus colonized a single supragingival site (3.33%). There was resistance to multiple antimicrobial agents of P. aeruginosa in 7 sites (100%) and S. aureus in 1 (100%)., Conclusions: This study revealed an important relationship between P. aeruginosa and S. aureus colonization at supragingival, subgingival and lingual sites and intubation, thus revealing antimicrobial resistant bacteria colonization of medical interest, which may contribute to the therapy choice directed to these microorganisms., (© 2022 Wiley Periodicals LLC.)

Background: This study evaluated the antihyperglycemic, anti-bone-resorptive, and anti-inflammatory efficacy of the probiotic Lactobacillus rhamnosus EM1107 in an experimental model of ligature-induced periodontitis in diabetic rats treated with metformin (Met)., Methods: A total of 114 male Wistar rats was randomly divided into six groups: (1) control, (2) experimental periodontitis (EP), (3) EP + diabetes mellitus (DM), (4) EP + probiotic (Prob), (5) EP + DM + Prob, and (6) EP + DM + Prob + Met. The animals received probiotic gavage during the 30 days of the experiment. DM was induced on the 14th day of the experiment with a single injection of streptozotocin into the penile vein, followed by ligature for EP induction and Met gavage on the 19th day and euthanasia on the 30th day. Heart blood, gingival and periodontal tissue, and hemimaxillae were collected. Biomolecular analysis, immunoenzymatic assays, histomorphology, and microtomographic analysis were performed. Data were statistically analyzed (p < 0.05)., Results: There was a significant reduction in interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in the Prob groups (p < 0.05) as well as in blood glucose levels in the Prob and Met groups (p < 0.001). In addition, histomorphological analysis revealed that the Prob groups had a reduction in inflammatory infiltrate. Tartrate-resistant acid phosphatase (TRAP) and microtomographic analyses showed that the EP/DM/Prob/Met group had significantly lower linear and volumetric bone loss than those who had no treatment (p < 0.01). SOD and GPx immunostaining decreased in all groups receiving probiotics., Conclusion: The findings suggest the immunoinflammatory efficacy of the probiotic L. rhamnosus EM1107 administered either alone or in association with Met in type 1 DM associated with periodontitis., (© 2022 American Academy of Periodontology.)

Objectives: To perform a comprehensive and integrative review of the available literature on the potential changes in the microbiome of healthy and individuals with diabetes under periodontal health and disease., Materials and Methods: The review was conducted by two independent reviewers. Indexed electronic databases (PubMed/Medline, Cochrane Library, Web of Science and Scopus) were searched, including articles published in English and dated from 5 years ago until December 2021. A manual search also was performed to identify co-related articles. Following the removal of duplicates and eligibility criteria, the articles were included in tables for analysis and described in the manuscript., Results: According to this review, diabetes mellitus was associated with significant changes in the subgingival and salivary microbiome, either in its association with periodontitis or in cases of periodontal health. In addition to affecting microbial diversity in terms of taxonomy, metagenomic studies have shown that this endocrine disorder may also be directly related to increased pathogenicity in the oral microbiome., Conclusion: Although the reviewed studies demonstrate important differences in the subgingival and salivary microbiome composition because of diabetes mellitus, further studies are needed to clarify the real effects of hyperglycemia on oral microbial profiles and support new diagnostic approaches and innovative treatments., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Silva, Casarin, Monajemzadeh, Bezerra, Lux and Pirih.)

The purpose of this study was to evaluate the effectiveness of photodynamic therapy as complementary therapy to mechanical instrumentation on periodontal residual pockets. This longitudinal, prospective, double-blind and controlled split-mouth clinical trial included one hundred and fourteen residual periodontal sites with probing depth ≥ 4 mm and bleeding on probing, which were distributed into two groups: 57 in the test group (SRP + aPDT) - using a low power laser application Therapy XT (DMC Equipamentos Ltda, São Carlos, São Paulo, Brazil) with operational parameters of 660 nm and 110 mW for 15s, and 57 in the control group (SRP). Oral hygiene conditions were evaluated, through the Visible Plaque Index (VPI) and Gingival Bleeding Index (GBI), as well as periodontal clinical outcomes, comprising the Bleeding on Probing (BOP), Probing Depth (PD) and Clinical Attachment Level (CAL) at baseline and after 3 months. Decrease of 17.74% was observed for the VPI after 3 months of follow-up, while the GBI was reduced by 19.91%, thus indicating statistically significant decreases for both parameters (p < 0.001). Decreases in VPI per site, BOP and PD and CAL gain between T 0 and T 3 in both treatment groups (p < 0.001) were observed, but no statistically significant intergroup differences were found (p > 0.05). Within the parameters used in this study, adjuvant aPDT to SRP did not lead additional benefits regarding the assessed clinical parameters after three months., Competing Interests: Declaration of Competing Interest The authors declare that they have no conflict of interest., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Background and objective: To evaluate the effects of antimicrobial photodynamic therapy (aPDT) with chloro-aluminum phthalocyanine (AlClFc) adjuvant to scaling and root planing (SRP) on periodontal clinical parameters of patients with chronic periodontitis. Materials and methods: Fifty-four periodontal sites were randomly distributed into two groups: 27 in the test group (SRP+aPDT)-using a low-power laser application Photon Lase III (DMC Equipamentos Ltda, São Carlos, São Paulo, Brazil) with operational parameters of 660 nm and 100 mW for 15 sec, and 27 in the control group (SRP). SRP was performed in a single session and the periodontal clinical parameters such as visible plaque index, bleeding on probing (BOP), probing depth (PD), and clinical attachment level were assessed at the baseline (T 0 ) and 3 months after aPDT (T 3 ). Results: Regarding BOP, a decrease in both treatment groups, the test group ( p  = 0.003) and control group ( p  = 0.001), was reported between T 0 and T 3 . A reduction in PD and clinical insertion gain for both treatment groups ( p  < 0.05) after 3 months of therapy was observed, although nonsignificant ( p  > 0.05) in intergroup comparison. Conclusions: aPDT with AlClFc adjuvant to SRP did not provide additional benefits in reducing PD and clinical insertion gain.