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Frontiers in Cellular and Infection... 2024Recent studies have demonstrated a positive role of hyaluronic acid (HA) on periodontal clinical outcomes. This study aimed to investigate the impact of four different...
INTRODUCTION
Recent studies have demonstrated a positive role of hyaluronic acid (HA) on periodontal clinical outcomes. This study aimed to investigate the impact of four different HAs on interactions between periodontal biofilm and immune cells.
METHODS
The four HAs included: high-molecular-weight HA (HHA, non-cross-linked), low-molecular-weight HA (LHA), oligomers HA (OHA), and cross-linked high-molecular-weight HA (CHA). Serial experiments were conducted to verify the influence of HAs on: (i) 12-species periodontal biofilm (formation and pre-existing); (ii) expression of inflammatory cytokines and HA receptors in monocytic (MONO-MAC-6) cells and periodontal ligament fibroblasts (PDLF) with or without exposure to periodontal biofilms; (iii) generation of reactive oxygen species (ROS) in MONO-MAC-6 cells and PDLF with presence of biofilm and HA.
RESULTS
The results indicated that HHA and CHA reduced the bacterial counts in a newly formed (4-h) biofilm and in a pre-existing five-day-old biofilm. Without biofilm challenge, OHA triggered inflammatory reaction by increasing IL-1β and IL-10 levels in MONO-MAC cells and IL-8 in PDLF in a time-dependent manner, whereas CHA suppressed this response by inhibiting the expression of IL-10 in MONO-MAC cells and IL-8 in PDLF. Under biofilm challenge, HA decreased the expression of IL-1β (most decreasing HHA) and increased IL-10 levels in MONO-MAC-6 cells in a molecular weight dependent manner (most increasing CHA). The interaction between HA and both cells may occur via ICAM-1 receptor. Biofilm stimulus increased ROS levels in MONO-MAC-6 cells and PDLF, but only HHA slightly suppressed the high generation of ROS induced by biofilm stimulation in both cells.
CONCLUSION
Overall, these results indicate that OHA induces inflammation, while HHA and CHA exhibit anti-biofilm, primarily anti-inflammatory, and antioxidant properties in the periodontal environment.
Topics: Biofilms; Hyaluronic Acid; Humans; Reactive Oxygen Species; Fibroblasts; Cytokines; Monocytes; Periodontal Ligament; Cell Line; Interleukin-1beta; Interleukin-10
PubMed: 38938883
DOI: 10.3389/fcimb.2024.1414861 -
International Journal of Dentistry 2024This study aimed to evaluate the effect of autoclave sterilization on the integrity and instruments' fracture number after multiple uses and cyclic fatigue of the...
This study aimed to evaluate the effect of autoclave sterilization on the integrity and instruments' fracture number after multiple uses and cyclic fatigue of the original WaveOne Gold (Dentsply Sirona Endodontics) compared to four replica-like instruments (TF4-Gold, Roll-Wave-Gold, W-File, and Micro-Gold). The instruments were analyzed by scanning electron microscope (SEM) before being used in root canal instrumentation (baseline). One hundred and fifty human molars, freshly extracted for orthodontic reasons or periodontal disease and with severe curvature (between 30° and 60°), were used. Fifty teeth were instrumented with 10 instruments from each group and were evaluated for integrity. After sterilization in an autoclave, the instruments were analyzed by SEM. This procedure was repeated twice more, totaling three rounds of instrumentation, sterilization, and SEM analysis. Ten unused instruments from each group were evaluated for resistance to cyclic fatigue in a static test using a motor and a device simulating a canal with a 60° curvature angle. The instruments were driven by the motor until separation, visually verified, and the time measured in seconds. Data were analyzed by -square, one-way ANOVA, and Tukey analysis, considering a significance level of 5%. It was found that there was no statistically significant difference between the groups tested in the effect of sterilization on the number of uses. The SEM analysis showed distortions in the instruments after the 3rd use. There was a statistically significant difference in the cyclic fatigue test between the results of WaveOne Gold, TF4 Gold, and Roll Wave Gold compared to W File and Micro Gold ( < 0.0001) and a statistically significant difference between the W File and Micro Gold groups ( < 0.0001). In conclusion, this study affirmed that WaveOne Gold, TF4-Gold, and Roll-Wave-Gold instruments exhibit comparable cyclic fatigue resistance. Besides, all examined instruments can be reliably employed for up to two cases.
PubMed: 38938694
DOI: 10.1155/2024/6628146 -
Journal of Dental Education Jun 2024The purpose of this study was to compare student learning of cone beam computed tomography (CBCT) interpretation using immersive virtual reality (VR) and...
OBJECTIVES
The purpose of this study was to compare student learning of cone beam computed tomography (CBCT) interpretation using immersive virtual reality (VR) and three-dimensional multiplanar (MP) reconstructions.
METHODS
Sixty first-year dental students were randomly allocated to two groups, VR and MP, and underwent a one-on-one educational intervention to identify anatomic structures using CBCT data. All participants completed three multiple-choice questionnaires (MCQs) before (T1), immediately after (T2), and 2 weeks following (T3) the intervention. Additionally, pre-survey, post-survey, NASA Task Load Index (NASA-TLX), and presence questionnaires were completed. Analysis of objective measures of performance on MCQs and subjective data from the questionnaires was completed (α = 0.05).
RESULTS
There was a significant increase in test performance and informational recall between T1-T2 and T1-T3 for VR and MP groups (p < 0.001). However, there were no significant differences in performance on MCQs between T2 and T3. Analysis of the Presence questionnaire indicated that the VR group felt decreased distraction (p = 0.013), increased realism (p = 0.035), and increased involvement (p = 0.047) during the educational intervention when compared with the MP group. Analysis of the NASA-TLX indicated that the VR group experienced more physical demand (p < 0.01) but similar cognitive demand when compared with the MP group. Qualitative responses indicated that the VR group had a more dynamic sense of visualization and manipulation compared to the MP group.
CONCLUSION
Results from this study show that VR is as effective as traditional MP methods of CBCT interpretation learning. Further benefits of VR educational intervention include increased involvement, realism and less distraction.
PubMed: 38938068
DOI: 10.1002/jdd.13631 -
International Journal of Paediatric... Jun 2024To compare two cone beam computed tomography (CBCT) analysis techniques for measuring tertiary dentin (TD) volume, density, and root length increase, after indirect pulp...
BACKGROUND AND AIM
To compare two cone beam computed tomography (CBCT) analysis techniques for measuring tertiary dentin (TD) volume, density, and root length increase, after indirect pulp therapy (IPT) in young permanent teeth with conventional periapical radiographs.
DESIGN
Comparative study design: Sixty-nine CBCT scans were taken initially (T1) and after 1 year (T2) of IPT. New CBCT analysis technique A, standardization, segmentation, and registration of T1 and T2 scans were performed using ITK-SNAP and 3D Slicer CMF to measure TD volume (mm), density (gray-level intensity), and root length increase (mm). In the traditional CBCT analysis technique B, analyses were conducted using the In-Vivo software to calculate TD thickness (mm), radiodensity (HU%), and root length increase (mm). Paired t-test and the intraclass correlation coefficient were calculated to compare and assess the reliability of all techniques.
RESULTS
No significant difference between the two techniques existed in the measurement of TD mineral density (Mean [SD]:A = 22.4 [15.4]; B = 24.4 [15.4]; p = .47). Technique A resulted in significantly higher root length increase values (Mean [SD]: A = 1.3 [0.6]; B = 1.1 [0.5]; p = .03). The two techniques showed acceptable reliability levels (0.76-0.99).
CONCLUSION
CBCT analysis techniques yielded similar findings for mineral density. The new CBCT volumetric analysis technique, although more laborious, produced higher values for root length increase, and allowed for measurement of dentin volume.
PubMed: 38937920
DOI: 10.1111/ipd.13232 -
Journal of Periodontology Jun 2024The composite outcome measure (COM) more comprehensively assesses the clinical efficacy of regenerative surgery than a single probing measurement. We aimed to assess...
BACKGROUND
The composite outcome measure (COM) more comprehensively assesses the clinical efficacy of regenerative surgery than a single probing measurement. We aimed to assess long-term success defined by the COM (clinical attachment level [CAL] gain of ≥3 mm and postsurgery probing pocket depth [PPD] ≤ 4 mm) and influencing factors of regenerative surgery using bone substitutes and resorbable collagen membrane (RM) for intra-bony defects (IBDs).
METHODS
We retrospectively collected data from patients who underwent regenerative surgery using deproteinized bovine bone mineral (DBBM) and RM for IBDs. CAL and PPD values were compared at baseline (preoperative), 1 year (short-term), and at the last follow-up (5-10 years). Multivariate logistic regressions were performed to identify factors influencing COM-based long-term success.
RESULTS
Eighty-one defects in 75 teeth of 33 patients who completed follow-up (6.5 ± 1.4 years) were included. One tooth was lost. All defects with complete follow-up exhibited long-term average CAL gain (3.00 ± 2.00 mm, 95% confidence interval [CI]: 2.56-3.44 mm, p < 0.001) and PPD reduction (2.06 ± 1.91 mm, 95% CI: 1.64-2.49 mm, p < 0.001). Long-term success was achieved in 38.8% of IBDs. CAL and PPD values were comparable between 1 year and the last follow-up. Logistic regression analyses revealed that male sex (odds ratio [OR] = 0.23, 95% CI: 0.07-0.75) and bleeding on probing (BOP) during supportive periodontal therapy (OR = 0.96, 95% CI: 0.94-0.99) were risk factors for long-term success.
CONCLUSIONS
Regenerative surgery with DBBM and RM for IBDs can achieve some degree of long-term success defined by COM. However, within this study's limitations, male sex and higher BOP incidence postoperatively are negatively associated with optimal long-term success.
CLINICAL TRIAL NUMBER
ChiCTR2300069016.
PubMed: 38937867
DOI: 10.1002/JPER.23-0701 -
Journal of Periodontology Jun 2024Recent studies suggest a role for microscopic crystalline particles of residual dental calculus in the pathogenesis of periodontitis. The purpose of this ex vivo study...
BACKGROUND
Recent studies suggest a role for microscopic crystalline particles of residual dental calculus in the pathogenesis of periodontitis. The purpose of this ex vivo study was to compare the effectiveness of scaling and root planing (SRP) alone versus SRP combined with 24% ethylenediamine-tetra acetic acid (EDTA) gel in removing calculus from extracted teeth and to determine the optimal length of time for application of the EDTA.
METHODS
Specimens consisted of 32 extracted teeth with heavy root calculus. A 4-mm diameter site was prepared on the root surface of each tooth which then underwent SRP. EDTA was applied to four timed groups: 30 s; 60 s; 120 s; and 180 s. Photomicrographs were taken at 40× magnification using white light (WL) and laser fluorescence (LF). Photomicrographs were analyzed using ImageJ. Specimens were also evaluated with scanning electron microscopy (SEM).
RESULTS
The mean area of residual calculus after SRP was 45%-53% (45.6% ± 19.6% WL, 53.8% ± 19.7% LF). Burnishing with EDTA for one minute following SRP reduced calculus to only 14%-18% (13.9% ± 12.5% LF, 18.2% ± 11.1% WL). Use of EDTA for greater than 1 min showed no further calculus removal. SEM revealed the surface of remaining calculus was altered by burnishing with EDTA.
CONCLUSION
SRP alone or SRP + 24% EDTA gel failed to remove all calculus. SRP alone removed >60% of calculus from root surfaces. Adjunctive use of 24% EDTA gel burnished on the root surface removed most of the calculus residual after SRP. Calculus remaining after EDTA burnishing exhibited a significantly altered morphologic appearance.
PubMed: 38937866
DOI: 10.1002/JPER.24-0191 -
Journal of Periodontology Jun 2024Diabetes is one of the major inflammatory comorbidities of periodontitis via 2-way interactions. Cystathionine γ-lyase (CTH) is a pivotal endogenous enzyme synthesizing...
BACKGROUND
Diabetes is one of the major inflammatory comorbidities of periodontitis via 2-way interactions. Cystathionine γ-lyase (CTH) is a pivotal endogenous enzyme synthesizing hydrogen sulfide (HS), and CTH/HS is crucially implicated in modulating inflammation in various diseases. This study aimed to explore the potential role of CTH in experimental periodontitis under a hyperglycemic condition.
METHODS
CTH-silenced and normal human periodontal ligament cells (hPDLCs) were cultured in a high glucose and Porphyromonas gingivalis lipopolysaccharide (P.g-LPS) condition. The effects of CTH on hPDLCs were assessed by Cell Counting Kit 8 (CCK8), real-time quantitative polymerase chain reaction (RT-qPCR), and enzyme-linked immunosorbent assay (ELISA). The model of experimental periodontitis under hyperglycemia was established on both Cth and wild-type (WT) mice, and the extent of periodontal destruction was assessed by micro-CT, histology, RNA-Seq, Western blot, tartrate-resistant acid phosphatase (TRAP) staining and immunostaining.
RESULTS
CTH mRNA expression increased in hPDLCs in response to increasing concentration of P.g-LPS stimulation in a high glucose medium. With reference to WT mice, Cth mice with experimental periodontitis under hyperglycemia exhibited reduced bone loss, decreased leukocyte infiltration and hindered osteoclast formation, along with reduced expression of proinflammatory cytokines interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) in periodontal tissue. RNA-seq-enriched altered NF-κB pathway signaling in healthy murine gingiva with experimental periodontitis mice under hyperglycemia. Accordingly, phosphorylation of p65 (P-p65) was alleviated in CTH-silenced hPDLCs, leading to decreased expression of IL6 and TNF. CTH knockdown inhibited activation of nuclear factor kappa-B (NF-κB) pathway and decreased production of proinflammatory cytokines under high glucose and P.g-LPS treatment.
CONCLUSION
The present findings suggest the potential of CTH as a therapeutic target for tackling periodontitis in diabetic patients.
PubMed: 38937859
DOI: 10.1002/JPER.23-0811 -
In Vivo (Athens, Greece) 2024Recent reports indicate that sclerostin is secreted by periodontal ligament tissue-derived (PDL) cells during orthodontic force loading and that the secreted sclerostin...
BACKGROUND/AIM
Recent reports indicate that sclerostin is secreted by periodontal ligament tissue-derived (PDL) cells during orthodontic force loading and that the secreted sclerostin contributes to bone metabolism. However, the detailed mechanism is poorly understood. The aim of this study was to determine how PDL cells affect bone formation.
MATERIALS AND METHODS
Rat periodontal ligament tissue was immunohistochemically stained for sclerostin. Cultured primary PDL cells, osteoblasts, and skin fibroblasts (Sfbs) isolated from rat periodontal ligament tissue, calvaria, and skin, respectively, were examined. Osteoblasts were cultured with control conditioned medium (Cont-CDM) and PDL cell culture conditioned medium (PDL-CDM) for up to 21 days. Cultured osteoblasts were then stained with alkaline phosphatase and von Kossa stain. Osteoblasts cultured in each conditioned medium were analyzed by real-time quantitative PCR for bone Gla protein (Bgp), Axin2, and Ki67 expression. PDL cells used to obtain conditioned medium were analyzed for Sost, Ectodin and Wnt1 expression and compared with expression in Sfbs.
RESULTS
Expression of sclerostin was observed in periodontal ligament tissue by immunohistochemical staining. The formation of mineralization nodules was inhibited in PDL-CDM compared with Cont-CDM in osteoblast culture. In PDL-CDM, the expression levels of Bgp and Axin2 in osteoblasts were decreased compared with Cont-CDM. In PDL cells, expression levels of Sost and Ectodin were much higher than in Sfbs; however, expression of Wnt1 was lower in PDL cells compared with Sfbs.
CONCLUSION
PDL cells secrete various proteins, including sclerostin and suppress osteogenesis in osteoblasts through the canonical Wnt pathway.
Topics: Periodontal Ligament; Animals; Osteogenesis; Osteoblasts; Rats; Culture Media, Conditioned; Cells, Cultured; Male; Fibroblasts; Cell Differentiation; Immunohistochemistry; Bone Morphogenetic Proteins; Genetic Markers
PubMed: 38936890
DOI: 10.21873/invivo.13609 -
Gene Jun 2024Periodontitis is associated with Fusobacterium nucleatum (F.n) infection. Although the colonization of renal tissue by F.n is well documented, its specific role in...
OBJECTIVES
Periodontitis is associated with Fusobacterium nucleatum (F.n) infection. Although the colonization of renal tissue by F.n is well documented, its specific role in kidney disease has yet to be determined. This study aimed to investigate the potential association between F.n-induced periodontitis and renal interstitial fibrosis.
METHODS
The rat gingival sulcus was injected with F.n suspension, while the control group (NC) was injected with PBS. The levels of total protein (TP), albumin (ALB), creatinine, and urea nitrogen (BUN) in rat serum and/or urine were quantified using the appropriate kits. Renal interstitial fibrosis and epithelial-mesenchymal transition (EMT) were evaluated in rats using Masson staining, Periodic Schiff-Methenamine (PASM) staining, and immunohistochemical staining. The levels of fibrosis- and EMT-related proteins and the TGF-β/SMAD2/3 and β-catenin signaling pathways were determined using Western blot analysis. F.n in the kidney tissues was quantitatively determined using bacterial 16S rRNA technology.
RESULTS
Serum levels of TP, ALB, creatinine, and BUN were not significantly decreased in F.n-infected rats with periodontitis. The levels of creatinine and ALB in the urine were not statistically different between two groups. Masson and PASM staining showed that F.n-induced periodontitis could promote renal interstitial fibrosis in rats. The levels of collagen I, fibronectin (FN), vimentin, and α-SMA were upregulated in the kidney tissues of rats with F.n-induced periodontitis and in F.n-treated HK-2 cells. However, E-cadherin levels were reduced. F.n promoted renal interstitial and HK-2 cell fibrosis in rats by modulating the TGF-β/SMAD2/3 and β-catenin signaling pathways. F.n colonization increased renal interstitial fibrosis in rats.
CONCLUSION
F.n-induced periodontitis promoted EMT by activating the TGF-β/SMAD2/3 and β-catenin signaling pathways, thus promoting renal interstitial fibrosis in rats.
PubMed: 38936784
DOI: 10.1016/j.gene.2024.148729 -
Journal of Dentistry Jun 2024To investigate the effectiveness of different adjunctive local treatments combined with non-surgical periodontal therapy (NSPT) to reduce pocket depth (PD), gain... (Review)
Review
OBJECTIVES
To investigate the effectiveness of different adjunctive local treatments combined with non-surgical periodontal therapy (NSPT) to reduce pocket depth (PD), gain clinical attachment level (CAL), and/or reduce glycated hemoglobin (HbA1c) in individuals with both type 2 diabetes mellitus (T2DM) and periodontitis in a systematic review and network meta-analysis.
DATA SOURCES
Publications were searched in Cochrane databases, EMBASE, Google Scholar, MEDLINE, PubMed, opengrey.eu, and www.
CLINICALTRIALS
gov up to May 29, 2024 with no language restriction.
STUDY SELECTION
Only randomized controlled trials (RCTs) were included. Network meta-analysis utilized frequentist models.
DATA
The network meta-analysis of 30 RCTs involving 1224 patients revealed that, in short-term (2-3 months) and medium-term (4-6 months), adjunctive local treatment involving statins or metformin significantly outperformed scaling and root planning (SRP) with/without additional interventions such as photodynamic and laser therapies (PDT/LT), phytotherapy, doxycycline, bisphosphonates, antibiotics, antiseptics, or placebo for reducing PD and/or gaining CAL. In the long-term (>6 months), statins yielded the most significant additional PD reduction and CAL gain, followed by antibiotics, compared to SRP with antiseptics or placebo. Only PDT/LT demonstrated significantly greater HbA1c reduction in the short term compared to SRP with/without statins, antiseptics, or placebo.
CONCLUSION
This study moderately supports that adding metformin or statins locally to NSPT may enhance PD reduction and CAL gain compared to SRP with/without placebo.
CLINICAL SIGNIFICANCE
Clinicians are guided to optimize adjunctive therapies, enhancing the health of patients with type 2 diabetes and periodontitis. A strategic approach is proposed to tackle systemic and oral health challenges simultaneously.
PubMed: 38936456
DOI: 10.1016/j.jdent.2024.105212