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BMC Oral Health Jun 2024The purpose of this study was to investigate the morphology of maxillary first premolar mesial root concavity and to analyse its relation to periodontal bone loss (BL)...
BACKGROUND
The purpose of this study was to investigate the morphology of maxillary first premolar mesial root concavity and to analyse its relation to periodontal bone loss (BL) using cone beam computed tomography (CBCT) and panoramic radiographs.
METHODS
The mesial root concavity of maxillary premolar teeth was analysed via CBCT. The sex and age of the patients, starting position and depth of the root concavity, apicocoronal length of the concavity on the crown or root starting from the cementoenamel junction (CEJ), total apicocoronal length of the concavity, amount of bone loss both in CBCT images and panoramic radiographs, location of the furcation, length of the buccal and palatinal roots, and buccopalatinal cervical root width were measured.
RESULTS
A total of 610 patients' CBCT images were examined, and 100 were included in the study. The total number of upper premolar teeth was 200. The patients were aged between 18 and 65 years, with a mean age of 45.21 ± 13.13 years. All the teeth in the study presented mesial root concavity (100%, n = 200). The starting point of concavity was mostly on the cervical third of the root (58.5%). The mean depth and buccolingual length measurements were 0.96 mm and 4.32 mm, respectively. Depth was significantly related to the amount of alveolar bone loss (F = 5.834, p = 0.001). The highest average concavity depth was 1.29 mm in the group with 50% bone loss. The data indicated a significant relationship between the location of the furcation and bone loss (X = 25.215, p = 0.003). Bone loss exceeded 50% in 100% of patients in whom the furcation was in the cervical third and in only 9.5% of patients in whom the furcation was in the apical third (p = 0.003).
CONCLUSIONS
According to the results of this study, the depth of the mesial root concavity and the coronal position of the furcation may increase the amount of alveolar bone loss. Clinicians should be aware of these anatomical factors to ensure accurate treatment planning and successful patient management.
Topics: Humans; Bicuspid; Cone-Beam Computed Tomography; Male; Female; Alveolar Bone Loss; Tooth Root; Adult; Middle Aged; Adolescent; Maxilla; Aged; Young Adult; Radiography, Panoramic; Tooth Cervix
PubMed: 38926720
DOI: 10.1186/s12903-024-04494-1 -
BMC Oral Health Jun 2024Human periodontal ligament stem cells (hPDLSCs) are important candidate seed cells for periodontal tissue engineering, but the presence of lipopolysaccharide(LPS) in...
BACKGROUND
Human periodontal ligament stem cells (hPDLSCs) are important candidate seed cells for periodontal tissue engineering, but the presence of lipopolysaccharide(LPS) in periodontal tissues inhibits the self-renewal and osteogenic differentiation of hPDLSCs. Our previous studies demonstrated that TAZ is a positive regulator of osteogenic differentiation of hPDLSCs, but whether TAZ can protect hPDLSCs from LPS is still unknown. The present study aimed to explore the regulatory effect of TAZ on the osteogenic differentiation of hPDLSCs in an LPS-induced inflammatory model, and to preliminarily reveal the molecular mechanisms related to the NF-κB signaling pathway.
METHODS
LPS was added to the culture medium of hPDLSCs. The influence of LPS on hPDLSC proliferation was analyzed by CCK-8 assays. The effects of LPS on hPDLSC osteogenic differentiation were detected by Alizarin Red staining, ALP staining, Western Blot and qRT-PCR analysis of osteogenesis-related genes. The effects of LPS on the osteogenic differentiation of hPDLSCs with TAZ overexpressed or knocked down via lentivirus were analyzed. NF-κB signaling in hPDLSCs was analyzed by Western Blot and immunofluorescence.
RESULTS
LPS inhibited the osteogenic differentiation of hPDLSCs, inhibited TAZ expression, and activated the NF-κB signaling pathway. Overexpressing TAZ in hPDLSCs partly reversed the negative effects of LPS on osteogenic differentiation and inhibited the activation of the NF-κB pathway by LPS. TAZ knockdown enhanced the inhibitory effects of LPS on osteogenesis.
CONCLUSION
Overexpressing TAZ could partly reverse the inhibitory effects of LPS on the osteogenic differentiation of hPDLSCs, possibly through inhibiting the NF-κB signaling pathway. TAZ is a potential target for improving hPDLSC-based periodontal tissue regeneration in inflammatory environments.
Topics: Humans; Periodontal Ligament; Lipopolysaccharides; Osteogenesis; NF-kappa B; Cell Differentiation; Signal Transduction; Stem Cells; Transcription Factors; Cells, Cultured; Cell Proliferation; Transcriptional Coactivator with PDZ-Binding Motif Proteins; Blotting, Western
PubMed: 38926705
DOI: 10.1186/s12903-024-04497-y -
Scientific Reports Jun 2024The aim of this study is to introduce a dental capping agent for the treatment of pulp inflammation (pulpitis). Nanohydroxyapatite with Elaeagnus angustifolia L. extract...
The aim of this study is to introduce a dental capping agent for the treatment of pulp inflammation (pulpitis). Nanohydroxyapatite with Elaeagnus angustifolia L. extract (nHAEA) loaded with metronidazole (nHAEA@MTZ) was synthesized and evaluated using a lipopolysaccharide (LPS) in vitro model of pulpitis. nHAEA was synthesized through sol-gel method and analyzed using Scanning Electron Microscopy, Transmission Electron Microscopy, and Brunauer Emmett Teller. Inflammation in human dental pulp stem cells (HDPSCs) induced by LPS. A scratch test assessed cell migration, RT PCR measured cytokines levels, and Alizarin red staining quantified odontogenesis. The nHAEA nanorods were 17-23 nm wide and 93-146 nm length, with an average pore diameter of 27/312 nm, and a surface area of 210.89 m/g. MTZ loading content with controlled release, suggesting suitability for therapeutic applications. nHAEA@MTZ did not affect the odontogenic abilities of HDPSCs more than nHAEA. However, it was observed that nHAEA@MTZ demonstrated a more pronounced anti-inflammatory effect. HDPSCs treated with nanoparticles exhibited improved migration compared to other groups. These findings demonstrated that nHAEA@MTZ could be an effective material for pulp capping and may be more effective than nHAEA in reducing inflammation and activating HDPSCs to enhance pulp repair after pulp damage.
Topics: Plant Extracts; Humans; Pulpitis; Metronidazole; Dental Pulp; Durapatite; Nanoparticles; Green Chemistry Technology; Drug Carriers; Stem Cells; Cell Movement; Cells, Cultured
PubMed: 38926433
DOI: 10.1038/s41598-024-65582-4 -
Journal of Prosthodontic Research Jun 2024Occlusal overload can cause late implant loss. However, whether the magnitude of the occlusal force is a risk factor for late implant loss remains unclear. Thus, this...
PURPOSE
Occlusal overload can cause late implant loss. However, whether the magnitude of the occlusal force is a risk factor for late implant loss remains unclear. Thus, this clinical study aimed to determine the relationship between the gonial angle (GoA), which is associated with the magnitude of occlusal force, and late implant loss.
METHODS
All implants with fixed prostheses placed at the Niigata University Hospital between April 2006 and August 2019 were included in this retrospective study. The implants with and without late loss were compared. Relevant variables, including smoking habits, diabetes mellitus status, remaining dentition, implant length and diameter, prosthesis design, retention systems, splinting, and GoA were assessed. Log-rank test and Cox proportional hazards regression analysis were used to estimate the adjusted hazard ratio (aHR) and to calculate the corresponding 95% confidence intervals (CI) for late implant loss.
RESULTS
A total of 919 patients (349 men and 570 women) with 2512 implants were included in this study. Cox proportional hazards regression analysis revealed that a 10° decrease in the GoA (aHR, 1.588; 95% CI, 1.115-1.766; P = 0.010), smoking habits (aHR, 3.909; 95% CI, 2.131-7.168; P < 0.001), and male sex (aHR, 2.584; 95% CI, 1.376-4.850; P = 0.003) were significantly associated with late implant loss.
CONCLUSIONS
Within the limitations of this retrospective study of 2512 implants, smaller GoA, smoking habits, and male sex were risk factors for late implant loss.
PubMed: 38925984
DOI: 10.2186/jpr.JPR_D_23_00267 -
Clinical Oral Investigations Jun 2024The primary objective of this in vitro experiment was an assessment of proliferative capacity, metabolic activity, and potential cellular detriment of human periodontal...
OBJECTIVES
The primary objective of this in vitro experiment was an assessment of proliferative capacity, metabolic activity, and potential cellular detriment of human periodontal ligament cells (hPDL) exposed to cigarette smoke (CS), electronic cigarette vapor (eCV), and heated tobacco product aerosol (HTP), or air (control).
MATERIALS AND METHODS
Using a CAD/CAM-designed exposition chamber, hPDL were exposed to CS, eCV, HTP, or air (control) based on the Health Canada Intense Smoking Regime. Cell proliferation, metabolic activity, and cellular detriment were assessed at various time points.
RESULTS
Compared to the control, hPDL exposed to CS exhibited significantly decreased cell numbers at all time points. HTP exposure led to reduced cell numbers 48 h and 72 h post-exposure, while eCV-exposed cells showed no significant decrease. The metabolic activity of eCV-treated hPDL was slightly reduced at 7 h but recovered at 24 h and 48 h. In contrast, CS-treated cells exhibited significantly decreased metabolic activity at 24 h and 48 h, and HTP-exposed cells showed a significant decrease after 48 h. Flow cytometry indicated both apoptotic and necrotic cell death following CS exposure, with necrotic cell death being more pronounced.
CONCLUSIONS
eCV and HTP demonstrated comparatively reduced detrimental effects on hPDL compared to CS.
CLINICAL RELEVANCE
The findings suggest that conventional cigarette smoke poses a substantial risk to periodontal health by significantly impairing cell proliferation and metabolic activity. However, alternatives such as eCV and HTP may offer a comparatively reduced risk.
Topics: Periodontal Ligament; Humans; Cell Proliferation; Cells, Cultured; Electronic Nicotine Delivery Systems; Tobacco Products; Flow Cytometry; In Vitro Techniques; Smoke; E-Cigarette Vapor; Aerosols; Nicotine; Apoptosis
PubMed: 38922383
DOI: 10.1007/s00784-024-05797-x -
Brazilian Dental Journal 2024This cross-sectional study aimed to investigate the association between developmental defects of enamel (DDE) and single nucleotide polymorphisms (SNPs) in the genes...
This cross-sectional study aimed to investigate the association between developmental defects of enamel (DDE) and single nucleotide polymorphisms (SNPs) in the genes encoding the vitamin D receptor (VDR) and parathyroid hormone (PTH). Orthodontic patients receiving treatment at a dental school were selected through convenience sampling. Intra-oral photographs were used to assess DDE, which were classified according to the criteria proposed by Ghanim et al. (2015) by a single calibrated examiner (Kappa>0.80). Enamel hypoplasia, molar-incisor hypomineralization (MIH), hypomimineralized second primary molar (HSPM), and non-MIH/HSPM demarcated opacities were considered for the analysis. Genomic DNA was extracted from buccal cells. The SNPs in VDR (rs7975232) and PHT (rs694, rs6256, and rs307247) were genotyped using real-time polymerase chain reactions (PCR). Statistical analyses were performed using the PLINK software (version 1.03, designed by Shaun Purcell, EUA). Chi-square or Fisher's exact tests were performed at a significance level of 5%. Ninety-one (n=91) patients (49 females and 42 males) (mean age of 14.1±5.8 years) were included. The frequency of DDE was 38.5% (35 patients). Genotype distributions were in Hardy-Weinberg equilibrium. No significant statistical association was found between DDE and the SNPs evaluated. A borderline association (p=0.09) was observed between DDE and the CC haplotype for SNP rs7975232 in VDR. In conclusion, the selected SNPs in VDR and PTH genes were not associated with DDE in the studied samples.
Topics: Humans; Receptors, Calcitriol; Polymorphism, Single Nucleotide; Female; Cross-Sectional Studies; Male; Parathyroid Hormone; Dental Enamel Hypoplasia; Child; Adolescent; Dental Enamel; Real-Time Polymerase Chain Reaction; Genotype
PubMed: 38922252
DOI: 10.1590/0103-6440202405900 -
Brazilian Dental Journal 2024This study aimed to evaluate the antimicrobial activity of calcium hypochlorite (Ca (OCl)2) and sodium hypochlorite (NaOCl) using confocal laser scanning microscopy...
This study aimed to evaluate the antimicrobial activity of calcium hypochlorite (Ca (OCl)2) and sodium hypochlorite (NaOCl) using confocal laser scanning microscopy (CLSM) and dentin organic matrix alteration by picrosirius staining and light microscopy (LM). Samples of human extracted teeth were infected with Enterococcus faecalis by centrifugation of the bacterial suspension and were treated with Ca(OCl)2 or NaOCl at 0.5%, 2.5%, and 6% for 15, 30, and 60 seconds. CLSM and viability staining were used to quantitatively analyze the proportions of dead/live bacteria in the canal lumen and border of the root canal. The data were analyzed by ANOVA and Fisher test. For LM analysis, one hundred bovine teeth were randomly divided into 10 test groups (n=10): G1- Without treatment; G2- 17% EDTA; G3- 6% NaOCl; G4- 6% NaOCl + EDTA; G5- 0.5% Ca(OCl)2; G6- 0.5% Ca(OCl)2 + EDTA; G7- 2.5% Ca(OCl)2; G8- 2.5% Ca(OCl)2 + EDTA; G9- 6% Ca(OCl)2; G10- 6% Ca(OCl)2 + EDTA. The samples were fragmented and stained with Picrosirius. Data were analyzed by Kruskal-Wallis and Dunn (P<0.05). There was a strong correlation between the results of the canal lumen and the border of the root canal (r=0.962). Both hypochlorites at a concentration of 0.5% showed less microbial reduction compared to 2.5% and 6% (P<0.05). There was less antimicrobial activity at 15 seconds compared to 30 and 60 seconds (P<0.05). Ca(OCl)2 and NaOCl showed similar results at the same concentrations (P>0.05). In conclusion, Ca(OCl)2 caused fewer alterations to the dentin organic matrix at concentrations of 0.5% and 2.5%. Ca(OCl)2 presents antimicrobial activity similar to NaOCl, and collagen damage is concentration-dependent.
Topics: Sodium Hypochlorite; Dentin; Calcium Compounds; Enterococcus faecalis; Collagen; Humans; Anti-Infective Agents; Root Canal Irrigants; Cattle; Microscopy, Confocal; Animals; Dental Pulp Cavity; In Vitro Techniques
PubMed: 38922251
DOI: 10.1590/0103-6440202405771 -
Brazilian Dental Journal 2024Studies regarding cytotoxic effects attributed to the use of adhesive bonding agents on pulp tissue are not conclusive. To point out whether these materials are safe for...
Studies regarding cytotoxic effects attributed to the use of adhesive bonding agents on pulp tissue are not conclusive. To point out whether these materials are safe for clinical use, in vivo exposure of dental pulp to adhesive bonding agents was simulated using an experimental setup in which Human Dental Pulp Stem Cells (hDPSC) are exposed to the action of two kinds of adhesives: self-etching adhesives and two-step bonding agents through a dentine barrier. Cytotoxic effects on these cells were evaluated by MTT assay protocol and fluorescence microscopy, and their results were contrasted to those obtained through Raman spectra taken on single hDPSCs. Overall, no significant cytotoxic effects were observed by combining all the techniques, and cell viability close to 90% was achieved for a dentine barrier of at least 1 mm thick. Moreover, Raman spectroscopy was able to detect structural DNA damage in some dental pulp cells when exposed to two-step bonding agents, suggesting that this technique could be considered a complementary tool with the potential to evaluate cell toxicity beyond cell viability.
Topics: Humans; Dental Pulp; Stem Cells; Spectrum Analysis, Raman; Dentin-Bonding Agents; Cell Survival; Microscopy, Fluorescence; Cells, Cultured
PubMed: 38922248
DOI: 10.1590/0103-6440202405529 -
Journal of Applied Oral Science :... 2024To evaluate the protective effect of an experimental solution containing TiF4/NaF on the development of radiation-induced dentin caries lesions.
OBJECTIVE
To evaluate the protective effect of an experimental solution containing TiF4/NaF on the development of radiation-induced dentin caries lesions.
METHODOLOGY
bovine root samples were irradiated (70Gy) and distributed as following (n=12/group): Commercial Saliva (BioXtra), NaF (500 ppm F-), TiF4 (500 ppm F), TiF4/NaF (TiF4: 300 ppm F-, NaF: 190 ppm F-), and Phosphate buffer solution (PBS, negative control). Biofilm was produced using biofilm from irradiated patients and McBain saliva (0.2% of sucrose, at 37oC and 5% CO2) for five days. The treatments were applied 1x/day. Colony-forming units (CFU) were counted and demineralization was quantified by transversal microradiography. The ANOVA/Tukey test was applied for all parameters.
RESULTS
All treatments reduced CFU for total microorganisms. TiF4 reduced Lactobacillus sp. (7.04±0.26 log10 CFU/mL) and mutans streptococci (7.18±0.28) CFU the most, when compared to PBS (7.58±0.21 and 7.75±0.17) and followed by NaF (7.12±0.31 and 7.34±0.22) and TiF4/NaF (7.16±0.35 and 7.29± 0.29). TiF4 and Commercial saliva showed the lowest integrated mineral loss (ΔZ-vol%.mm) (1977±150 and 2062±243, respectively) when compared to PBS (4540±335), followed by NaF (2403±235) and TiF4/NaF (2340±200). Commercial saliva was the only to significantly reduce mineral loss (LD-µm) (111±25) compared to PBS (153±24).Mean mineral loss (R-vol%) decreased by 35.2% for TiF4 (18.2±3.3) when compared to PBS (28.1±2.9) Conclusion: TiF4/NaF has a comparable anti-cariogenic effect to TiF4 and Commercial saliva under the model in this study.
Topics: Sodium Fluoride; Cattle; Animals; Dentin; Dental Caries; Biofilms; Fluorides; Saliva; Streptococcus mutans; Time Factors; Analysis of Variance; Microradiography; Cariostatic Agents; Reproducibility of Results; Lactobacillus; Colony Count, Microbial; Tooth Demineralization; Humans; Materials Testing; Reference Values; Treatment Outcome; Statistics, Nonparametric; Titanium
PubMed: 38922242
DOI: 10.1590/1678-7757-2024-0024 -
Journal of Applied Oral Science :... 2024This study compared three protocols for developing artificial white spot lesions (WSL) using biofilm models. (Comparative Study)
Comparative Study
OBJECTIVE
This study compared three protocols for developing artificial white spot lesions (WSL) using biofilm models.
METHODOLOGY
In total, 45 human enamel specimens were sterilized and allocated into three groups based on the biofilm model: Streptococcus sobrinus and Lactobacillus casei (Ss+Lc), Streptococcus sobrinus (Ss), or Streptococcus mutans (Sm). Specimens were incubated in filter-sterilized human saliva to form the acquired pellicle and then subjected to the biofilm challenge consisting of three days of incubation with bacteria (for demineralization) and one day of remineralization, which was performed once for Ss+Lc (four days total), four times for Ss (16 days total), and three times for Sm (12 days total). After WSL creation, the lesion fluorescence, depth, and chemical composition were assessed using Quantitative Light-induced Fluorescence (QLF), Polarized Light Microscopy (PLM), and Raman Spectroscopy, respectively. Statistical analysis consisted of two-way ANOVA followed by Tukey's post hoc test (α=0.05). WSL created using the Ss+Lc protocol presented statistically significant higher fluorescence loss (ΔF) and integrated fluorescence (ΔQ) in comparison to the other two protocols (p<0.001).
RESULTS
In addition, Ss+Lc resulted in significantly deeper WSL (137.5 µm), followed by Ss (84.1 µm) and Sm (54.9 µm) (p<0.001). While high mineral content was observed in sound enamel surrounding the WSL, lesions created with the Ss+Lc protocol showed the highest demineralization level and changes in the mineral content among the three protocols.
CONCLUSION
The biofilm model using S. sobrinus and L. casei for four days was the most appropriate and simplified protocol for developing artificial active WSL with lower fluorescence, higher demineralization, and greater depth.
Topics: Biofilms; Humans; Streptococcus mutans; Dental Caries; Dental Enamel; Lacticaseibacillus casei; Time Factors; Reproducibility of Results; Streptococcus sobrinus; Spectrum Analysis, Raman; Analysis of Variance; Microscopy, Polarization; Statistics, Nonparametric; Tooth Remineralization; Reference Values; Saliva; Tooth Demineralization; Fluorescence
PubMed: 38922241
DOI: 10.1590/1678-7757-2023-0458