ARTICLE | doi:10.20944/preprints201902.0145.v1
Subject: Medicine And Pharmacology, Dentistry And Oral Surgery Keywords: multilevel analysis; periodontal disease; nonsurgical periodontal therapy; risk factor; modelling; periodontal healing
Online: 18 February 2019 (07:31:01 CET)
This retrospective study aimed to investigate the effect of known risk factors on nonsurgical periodontal treatment (NSPT) response using a pocket depth fine-tuning multilevel linear model (MLM). Thirty-seven patients (24 males and 13 females) with moderate to severe chronic periodontitis were treated with nonsurgical periodontal therapy. Follow-up visits at 3, 6, and 12 months included measurement of several clinical periodontal parameters. Data were extracted from a database system. Probing depth (PD) and Clinical Attachment Loss (CAL) reductions after NSPT in an overall of 1416 initially affected sites (baseline PD ≥ 4 mm), distributed on 536 teeth, were analyzed against known risk factors at three hierarchical levels (patient, tooth and site). The variance component models fitted to assess the three-level variance of PD and CAL decrease for each post-treatment follow-up showed that all levels contributed significantly to the overall variance (P < 0.001). Patients that underwent NSPT and were continually monitored had very curative results. All three hierarchical levels included risk factors who had impact on the to influence the magnitude of PD and CAL reduction. Specifically, the tooth’s type, surfaces involved and teeth mobility site-level risk factors showed the highest influence on these reductions, being highly relevant factors for the NSPT success.
REVIEW | doi:10.20944/preprints202301.0416.v1
Subject: Medicine And Pharmacology, Dentistry And Oral Surgery Keywords: Inflammasome; NLRP3; periodontal disease; periodontal pathogen; IL-1β
Online: 23 January 2023 (15:07:31 CET)
Dr. Jurg Tschopp created the word "inflammasome" in 2002. Inflammasome activation and its function in disease processes have been the subject of significant investigation over the last 15 years. Four important inflammasomes have been identified: NLRP1, NLRP3, NLRC4, and AIM2. When these inflammasomes are activated, they process and secrete inflammatory cytokines such as IL-1b and IL-18, as well as cause pyroptosis, an inflammatory form of cell death. In this review, we will look at how these inflammasomes have been connected to Periodontitis pathogenesis.
ARTICLE | doi:10.20944/preprints202301.0363.v1
Subject: Medicine And Pharmacology, Dentistry And Oral Surgery Keywords: Periodontal Disease; Electronic Dental Record; Longitudinal Data; Data Quality; Dental Infor-matics; Clinical Course of Periodontal Disease; Periodontal Cohort Generation
Online: 19 January 2023 (13:01:27 CET)
Objective: Determine the feasibility of utilizing longitudinal electronic dental record (EDR) data to track change over time in patient periodontal disease (PD) and to generate three patient cohorts: 1) patients whose disease did not change over time, 2) patients whose PD progressed, and 3) patients whose disease improved over time using informatics approaches. Methods: We conducted a retrospective study of 28,908 patients who received a comprehensive oral evaluation between January 1, 2009, and December 31, 2014, at the Indiana University School of Dentistry (IUSD) clinics. We developed and tested three automated computer applications to: 1) diagnose periodontitis cases from periodontal charting, 2) retrieve clinician-documented diagnoses from clinical notes, and 3) track disease change over time. We also evaluated the density of longi-tudinal EDR data for the following follow-up times: 1) none, 2) up to 5 years, 3) >5 and <=10 years, and 4) >10 and <=15 years Results: Thirty-four percent (n=9,954) of the study cohort had up to five years of follow-up visits with an average of 2.78 visits with periodontal charting information. An average of three patient visits per year that contained periodontal charts (63,552) were utilized to obtain a diagnosis, which is considered excellent. For clinician-documented diagnoses from clinical notes, 42% of patients (n=5,562) had at least two PD diagnoses to determine their disease change. In this cohort with cli-nician-documented diagnoses, 72% percent of patients (n=3,919) did not have a disease status change between their first and last visits, 669 (13%) patients' disease status progressed, and 589 (11%) patients’ disease improved. Conclusions: This study demonstrated the feasibility of utilizing longitudinal EDR data to track disease changes over 15 years during the observation study period. We found excellent longitudinal data when diagnoses generated from periodontal charting were considered (three visits per pa-tient). This information can be now utilized for studying the clinical course of periodontitis.
CASE REPORT | doi:10.20944/preprints202207.0240.v1
Subject: Medicine And Pharmacology, Dentistry And Oral Surgery Keywords: periodontitis; periodontal disease; necrotizing periodontitis; periodontal treatment; multiple sclerosis; relapsing-remitting multiple sclerosis
Online: 18 July 2022 (02:52:21 CEST)
Multiple sclerosis (MS) and necrotizing periodontitis (NP) are two diseases whose aetiology and pathophysiology do not seem to have a common link; however, the treatment of MS with monoclonal antibodies and the decrease in humoral immunity that this entails can be a trigger or an aggravation in patients who present NP. We present a clinical case of NP in which its clinical manifestations, treatment and evolution during therapy with ocrelizumab are reflected. During the evolution of the case, a rapid progression of NP was evidenced. During her evolution, the patient suffered bilateral pneumonia due to COVID requiring treatment with corticosteroids and antibiotics, which led to clinical relief of her NP. Given this important clinical finding, we consider of great interest the regulated dental monitoring of those patients with MS before, during and after the administration of monoclonal antibodies to prevent periodontal deterioration.
ARTICLE | doi:10.20944/preprints202107.0529.v1
Subject: Physical Sciences, Acoustics Keywords: diode laser, imaging, periodontal, photoacoustic.
Online: 23 July 2021 (08:10:44 CEST)
Inflammation of the periodontal tissue (periodontitis) is the highest problem of oral health in Indonesia after caries. Photoacoustic imaging (PAI) is a new imaging technique that can be simply constructed using a diode laser combined with a condenser microphone. This study aims to determine that a simple PAI system was able to image periodontal disease in animal model. Samples of the study were normal periodontal and periodontitis tissue, obtained from Sprague-Dawley rats that were divided into four groups, i.e. the control group, treatment group 1 (7 days periodontitis induction), treatment group 2 (11 days periodontitis induction), and treatment group 3 (14 days periodontitis induction). The PAI system was controlled by Labview and Arduino IDE software from a personal computer. Results of the study reveal that the optimal frequency of laser modulation for periodontal tissue imaging was 19 kHz with duty cycle of 50%. Photoacoustic (PA) intensity was obtained from higher to lower of -68,71 dB (treatment group 3), -70,69 dB (treatment group 2), -71,69 dB (treatment group 1), and -73,07 dB (control group) respectively. The photoacoustic images were analyzed to define the contrast between sample and media. The PA intensity of the samples were higher than media. Therefore, this study demonstrate the feasibility of simple PAI system to differentiate normal periodontal tissue and periodontitis.
REVIEW | doi:10.20944/preprints202305.0894.v1
Subject: Medicine And Pharmacology, Dentistry And Oral Surgery Keywords: storage media; avulsed teeth; periodontal ligament
Online: 12 May 2023 (05:37:43 CEST)
Background: Dental avulsion is the most serious dentoalveolar traumas because its management requires immediate reimplantation to maintain the periodontal ligament. The success of the treatment depends largely on the appropriate storage medium that ensures the viability of the periodontal cells. The purpose of this review was to identify the most efficient media to store and transport avulsed permanent teeth, according to the viability of the periodontal ligament cells. Methods: The Scopus, Web of Science and PubMed electronically searched using the keywords “Storage media”; “Avulsed teeth”; and “Periodontal ligament”. The inclusion criteria were in vitro studies and articles published in English. The exclusion criteria were literature reviews, studies in primary teeth, studies in animals, and cell culture studies. Results: Hank’s saline solution and honey were equally effective, maintaining a cell viability rate of 98.89% and 96.43%, respectively, over a period of 3 hours. Ringer’s lactate solution maintained the viability of 906.40 viable cells/mm3 at 1 hour. Propolis maintained the viability of 285,000 cells/mm3 at 45 minutes, and the Neem extract maintained a cell viability rate of 88% at 30 minutes. Conclusions: Hank’s saline solution is the most effective storage medium for maintaining the viability of periodontal cells in avulsed teeth.
REVIEW | doi:10.20944/preprints202304.1029.v1
Subject: Medicine And Pharmacology, Dentistry And Oral Surgery Keywords: Entamoeba Gingivalis; Periodontal Disease; Prevalence; review
Online: 27 April 2023 (04:13:01 CEST)
The oral cavity is environment to a diverse range of organisms that make up an essential element of the human microbiota. There are 50-1000 kinds of microorganisms capable of colonizing the mouth. The entamoeba parasites have at minimum 7 species (E. histolytica, E. dispar, E. moshkovskii, E. coli, E. polecki E. hartmann, E. gingivalis). These parasites are parasitic single-celled organisms and Entamoeba gingivalis was the first amoeba to be described in 1849 that was capable of existing in humans. It was shown that only Entamoeba gingivalis is able to colonize the oral cavity. The aim of this study was to evaluate prevalence of E. Gingivalis in periodontal disease using two electronic database search engines. In order to have a broader view of the subject, a comprehensive manual search was conducted on these content aggregators and the initial search resulted in 277 articles using the keywords „Entamoeba gingivalis”, „periodontitis”, „E. gingivalis”, „periodontal disease”, „prevalence”, and „incidence”, in different combinations. The results showed that 755 cases were infected with Entamoeba gingivalis out of a total number of 1,729 patients diagnosed with periodontal disease indicating a global prevalence of 43%. When comparing different stages of periodontal diseases results revealed that the prevalence in patients with gingivitis was 58% while in periodontitis group the prevalence was 44%. Overall prevalence of Entamoeba Gingivalis based on gender was 43 % in female patients whilst in male patients was 47%. Based on the results it can be concluded that the higher incidence of Entamoeba Gingivalis in people with periodontal disease compared to healthy people is more than just a sign of the disease; it may also be linked to the severity of the condition and its propensity to progress.
ARTICLE | doi:10.20944/preprints202302.0112.v1
Subject: Medicine And Pharmacology, Dentistry And Oral Surgery Keywords: Thalassemia major; periodontal diseases; interleukins; gingivitis
Online: 7 February 2023 (02:51:51 CET)
Periodontal diseases and Thalassemia Major (TM), which are two chronic inflammatory diseases, are associated with increased levels of proinflammatory cytokines in bio-fluids. Interleukin (IL)-6 and IL-8 have been identified as potent proinflammatory biomarkers in periodontal diseases as well as in patients with β-thalassemia (TM-β). This suggests that patients with TM-β and gingival inflammation have two chronic inflammatory conditions, each of which may affect the other. The objective of this pioneer research was to evaluate the effect of oral hygiene maintenance and care on serum levels of IL-6 and IL-8. 31 participants selected after screening and were given Non-surgical periodontal therapy(NSPT). IL-6 and IL-8 were evaluated by enzyme linked immunohistochemistry assay (ELISA) at baseline and compared at 6 weeks after NSPT. Statistical analysis was done with SPSS v23. The comparison from the baseline to 6-weeks follow-up for both IL-6 and IL-8 was done using Wilcoxon Signed rank test. The descriptive statistics are represented as median and inter quartile range (IQR). Highly significant improvement (p-<0.000) was found for IL-6 and IL-8 when compared at 6 weeks from baseline. Results provide a gateway to new modality in lowering systemic burden of the disease, thereby reducing morbidity, via local measures or oral care.
ARTICLE | doi:10.20944/preprints202010.0640.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: diagnosis; metabolomics; periodontal therapy; periodontitis; saliva
Online: 30 October 2020 (13:28:58 CET)
Pattern analysis of salivary metabolic profile has been proven accurate to discriminate generalized periodontitis (GP) patients from healthy individuals (HI) as disease modifies the salivary concentrations of specific metabolites. Due to the scarcity of data in the literature, the aim of this study was to determine whether non-surgical periodontal therapy (NST) could change salivary metabolomic profile in GP to one more similar to HI. Unstimulated whole saliva of 11 HI and 12 GP patients were obtained prior to and 3 months after NST. Metabolic profiling was performed using Nuclear Magnetic Resonance (NMR) spectroscopy, followed by supervised multivariate statistical approach on entire saliva spectra and partial least square (PLS) discriminant analysis. In GP group, periodontal treatment improved all clinical parameters, but not all the diseased sites were eradicated. PLS revealed an accuracy of 100% in discriminating the metabolomic profile of each GP patient before and after NST. OPLS was able to discriminate the 3 groups of subjects with an accuracy of 85.6%. However the post-NST metabolic profile of GP patients could not be completely assimilated to that of HS. Although NST may produce significant changes in the metabolic profile, GP patients maintained a distinctive fingerprint compared to HI.
REVIEW | doi:10.20944/preprints201906.0007.v1
Subject: Medicine And Pharmacology, Dentistry And Oral Surgery Keywords: Vitamin C, Periodontal disease, Periodontitis, Gingivitis
Online: 3 June 2019 (08:46:35 CEST)
Vitamin C is important in preventing and slowing the progression of many diseases. There is significant evidence linking periodontal disease and vitamin C. We aimed to systematically review studies addressing the relationship between vitamin C and periodontal disease and the preventive ability of vitamin C against periodontal disease. Electric searches were performed using PubMed, EMBASE, Cochrane Library, and Web of Science. Studies addressing the relationships between periodontal disease and vitamin C in adults aged over 18 years were included. Quality assessment was done using Critical Appraisal Skills Program guideline and GRADE-CERQual. Seventy hundred and sixteen articles were retrieved and fifteen articles (7 cross-sectional studies, 2 case-control studies, 2 cohort studies, and 4 randomized controlled trial [RCT]) were selected by reviewing all articles. Vitamin C intake and blood level were negatively related to periodontal disease in all 7 cross-sectional studies. Subjects who suffer from periodontitis presented lower vitamin C intake and lower blood vitamin C level than subjects without periodontal disease in the two case-control studies. Patients with lower dietary intake or lower blood level of vitamin C showed greater progression of periodontal disease than did the controls. Intervention using vitamin C administration improved gingival bleeding in gingivitis but not in periodontitis. Alveolar bone absorption was also not improved. The present systematic review suggested that vitamin C contributes to reduced risk of periodontal disease.
Subject: Social Sciences, Psychology Keywords: teeth; greyhound; intervention; brushing; calculus; gingivitis; dental; periodontal
Online: 19 May 2021 (07:53:28 CEST)
Periodontal disease is one of the most common conditions affecting dogs worldwide and is reported to be particularly prevalent in racing greyhounds. A range of potential risk factors have been hypothesised. Previous research has suggested, regular tooth brushing can reduce both calculus and gingivitis, but the frequency required is unclear. Here, we report a controlled blinded in-situ in which kennel staff brushed 160 racing greyhounds’ teeth (living at six kennel establishments), either weekly, daily or never over two-month period. All visible teeth were scored for calculus and gingivitis, using previously validated scales. We calculated average scores for each of three teeth groups and overall averaging the teeth groups. Changes were compared to baseline. After two months, the total calculus scores (controlling for baseline) were significantly different in the three treatemnet groups, (F(2,129) = 10.76, p<0.001) with both weekly and daily brushing resulting in significant reductions. Gingivitis was also significantly different (F(2,128) = 4.57, p=0.012), but in this case, only daily brushing resulted in a significant reduction. Although dogs in different kennels varied significantly in their levels of both calculus (F(5,129) =8.64, p<0.001), and gingivitis (F(5,128)=3.51 p=0.005), the intervention was generally similarly effective in all establishments. Teeth groups varied and incisors were not significantly affected by treatment. Since trainers implementing the routine, reported minimal time commitment and positive experiences, we suggest that daily brushing is recommended for racing greyhounds, and that demonstrations should include attention to all teeth groups including incisors. Similar trials need to be conducted with retired greyhounds since these have been shown to present particularly high levels of periodontal disease.
REVIEW | doi:10.20944/preprints202305.1601.v1
Subject: Medicine And Pharmacology, Dentistry And Oral Surgery Keywords: COVID-19; SARS-CoV-2; Periodontitis; Herpesviruses; Periodontal; Biomarkers
Online: 23 May 2023 (07:43:32 CEST)
The COVID-19 pandemic has brought marked changes worldwide to the management of airborne infectious diseases. It sparked the development of the SARS-CoV-2 vaccine and pharmacotherapeutics to prevent infection and increase the survival rate during the acute viral phase and the comorbidities associated with COVID-19. Periodontal disease may increase the morbidity and perhaps the mortality of a COVID-19 infection. However, the molecular interaction between periodontitis and COVID-19 infection remains undetermined. A potential pathogenic co-morbidity may involve periodontal pathogenic release of destructive cytokines in the highly inflamed connective tissue and risk for COVID-19. Additional biomarkers such as C-reactive proteins appear to play a role for risk and pathogenesis of COVID-19. The potential of herpesviruses, especially as it is related to aggressive periodontitis may also be a comorbidity for COVID-19. This paper reviews available evidence on the bidirectional association between periodontitis and COVID-19.
ARTICLE | doi:10.20944/preprints202102.0062.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: Stroke; Periodontitis; Periodontal disease; protein-protein network interaction; Bioinformatics
Online: 1 February 2021 (16:45:13 CET)
The clinical interaction between stroke and periodontitis has been consistently studied and confirmed. Hence, forecasting potentially new protein interactions in this association using bioinformatic strategies presents potential interest. In this exploratory study, we conducted a protein-protein network interaction (PPI) search with documented encoded proteins for both stroke and periodontitis. Genes of interest were collected via GWAS database. The STRING database was used to predict the PPI networks, first in a sensitivity purpose (confidence cut-off of 0.7), and then with a highest confidence cut-off (0.9). Genes over-representation was inspected in the final network. As a result, we foresee a prospective protein network of interaction between stroke and periodontitis. Inflammation, pro-coagulant/pro-thrombotic state and ultimately atheroma plaque rupture is the main biological mechanism derived from the network. These pilot results may pave the way to future molecular and therapeutic studies to further comprehend the mechanisms between these two conditions.
ARTICLE | doi:10.20944/preprints202010.0145.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: Parkinson’s disease; Periodontitis; Periodontal disease; Mendelian Randomization; Bioinformatics; Oral Health
Online: 7 October 2020 (08:26:14 CEST)
Latest evidence revealed a possible association between Parkinson’s disease (PD) and periodontitis. We explored the causal relationship of this association through two-sample Mendelian randomization (MR) in European ancestry populations. To this end, we used openly accessible data of genome-wide association studies (GWAS) on PD and periodontitis. As instrumental variables for periodontitis, seventeen single-nucleotide polymorphisms (SNPs) from a GWAS of periodontitis (1817 periodontitis cases vs. 2215 controls) and forty-five SNPs from a GWAS of PD (20,184 cases and 397,324 controls). Eight non-overlapping SNPs of periodontitis from an additional GWAS assisted in the validation of association being studied. Multiple approaches of MR were carried-out. There was no evidence of genetic liability of periodontitis being associated with a higher risk of PD (B= -0.0003, Standard Error [SE] 0.0003, P = 0.26). The eight independent SNPs (B= -0.0000, SE 0.0001, P = 0.99) validated this outcome. We found no association of genetically primed PD towards periodontitis (B= -0.0001, SE 0.0001, P = 0.19). This MR study found no conclusive evidence to support a bidirectional causal genetic liability between PD and periodontitis. Further GWAS studies are needed to confirm the consistency of these results.
ARTICLE | doi:10.20944/preprints202009.0220.v1
Subject: Medicine And Pharmacology, Dentistry And Oral Surgery Keywords: feasibility; acceptability; adherence; attrition rate; periodontal therapy; milk fortification; pregnancy
Online: 10 September 2020 (04:44:05 CEST)
This study aims to assess the acceptability, adherence, and retention of a feasibility trial on milk fortification with calcium and vitamin D (Ca+VitD) and periodontal therapy (PT) among low income Brazilian pregnant women with periodontitis (IMPROVE trial). This 2x2 factorial feasibility trial used a mixed-methods evaluation. 69 pregnant women were randomly allocated to four groups: 1.fortified sachet with Ca+VitD and milk plus early PT (throughout gestation); 2.placebo and milk plus early PT; 3.fortified sachet with Ca+VitD and milk plus late PT after childbirth; 4.placebo and milk plus late PT. Data were collected via questionnaires, field notes, participant flow logs, treatment diary, and focal group discussions. Quantitative and qualitative data were analysed using appropriate descriptive statistics and content analysis, respectively. Eligibility rate (12%) was below the target of 15%, but participation (76.1%) and recruitment rate (2 women/week) exceeded the targets. Retention rate (78.6%) was slightly below the target (80%). Adherence to the PT was significantly higher in the early treatment groups (98.8%) compared to the late treatment groups (29%). All women accepted the random allocation and baseline groups were balanced. There was no report of adverse events. This multi-component intervention is acceptable, well-tolerated, and feasible among low-risk pregnant women in Brazil.
ARTICLE | doi:10.20944/preprints202009.0050.v1
Subject: Medicine And Pharmacology, Dentistry And Oral Surgery Keywords: Parkinson’s disease; Periodontitis; Periodontal disease; protein-protein network interaction; Bioinformatics
Online: 3 September 2020 (04:13:12 CEST)
Recent studies supported a clinical association between Parkinson’s Disease (PD) and periodontitis. Hence, investigating possible protein interactions between these two conditions is of interest. In this study, we conducted a protein-protein network interaction analysis with recognized genes encoding proteins for PD and periodontitis. Genes of interest were collected via GWAS database. Then, we conducted a protein interaction analysis using STRING database, with a highest confidence cut-off of 0.9. Our protein network casted a comprehensive analysis of potential protein-protein interactions between PD and periodontitis. This analysis may underpin valuable information for new candidate molecular mechanisms between PD and periodontitis and may serve new potential targets for research purposes. These results should be carefully interpreted giving the limitations of this approach.
ARTICLE | doi:10.20944/preprints201807.0367.v1
Subject: Medicine And Pharmacology, Dentistry And Oral Surgery Keywords: nanoparticles; poly lactic-co-glycolic acid; metformin; periodontal disease; inflammation
Online: 20 July 2018 (03:40:29 CEST)
The aim of this study was synthesize and evaluate the effects of Poly (D, L-Lactide-co-glycolide) (PLGA) Nanoparticles (NPs) of metformin (PLGA+ Met) on inflammation, and bone loss in a ligature-induced periodontitis rat model. The prepared NPs were characterized by mean diameter, size particle, polydispensity index and encapsulation efficiency by Atomic force microscopy (AFM). Male albino Wistar rats were randomly divided into four groups of 20 rats in each group, and given the following treatments for 10 days to evaluate in vivo activity: (1) Sham: no ligature + water; (2) Positive control: ligature + water (with Periodontal disease and Diabetes); (3) ligature + PLGA+ 10 mg/kg Met (With Periodontal disease and Diabetes); and (4) ligature + PLGA+ 100 mg/kg Met (with Periodontal disease and Diabetes). Water or PLGA + Met was administered orally by gavage. Maxillae were fixed and scanned using Micro-computed Tomography (μCT) to quantify linear of bone loss. Histopathological characteristics were assessed through immunohistochemical staining for Osteocalcin, Cathepsyn K, RANKL/RANK/OPG pathway. IL-1β and TNF-α from gingival tissues were analysed by Elisa immunoassay. Quantitative RT-PCR reaction was used to evaluate gene expression of AMPK, NF-κB p-65, Hmgb1 and TAK-1 from gingival tissues. Statistical analysis was performed using one-way ANOVA at 5% significance. The mean diameter of MET-loaded PLGA nanoparticles was in a range of 457.1 ± 48.9 nm with a polydispersity index of 0.285, zeta potential: 8.16 ± 1.1 mV and entrapment efficiency (EE) was 70%. The results suggest that the addition of MET in the core slightly affected the particle sizes. Treatment with PLGA+ 10 mg/kg Met showed low inflammatory cells, decreased bone loss and integrity cement and levels of IL-1β, and TNF-α (p < 0.05) were significantly reduced. Additionally, weak staining was shown by RANKL, Cathepsyn K, OPG, and osteocalcin. Radiographically, linear measurements showed a statistically significant reduction in bone loss after treatment with PLGA+ 10 mg/kg Met compared to the positive control (p < 0.05). RT-PCR showed increased AMPK expression (p < 0.05) and decreased expression of NF-κB P65, HMGB1 and TAK-1 after PLGA+ 10 mg/kg Met (p < 0.05). The PLGA nanoparticle + 10 mg/kg Met decreased glucose levels and also decreased the inflammatory response, and bone loss in ligature-induced periodontitis in rats.
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: 3D printing; tissue engineering; periodontal regeneration; scaffolds; stem cells; growth factors
Online: 24 November 2020 (16:18:17 CET)
The three-dimensional printing of scaffolds is an interesting alternative to the traditional techniques of periodontal regeneration. This technique uses computer assisted design and manufacturing after CT scan. After 3D modelling, individualized scaffolds are printed by extrusion, selective laser sintering, stereolithography, or powder bed inkjet printing. These scaffolds can be made of one or several materials such as natural polymers, synthetic polymers, or bioceramics. They can be monophasic or multiphasic and tend to recreate the architectural structure of the periodontal tissue. In order to enhance the bioactivity and have a higher regeneration, the scaffolds can be embedded with stem cells and/or growth factors. This new technique could enhance a complete periodontal regeneration. This review summarizes the application of 3D printed scaffolds in periodontal regeneration. The process, the materials and designs, the key advantages and prospects of 3D bioprinting are highlighted, providing new ideas for tissue regeneration.
ARTICLE | doi:10.20944/preprints202011.0455.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: NHANES; periodontal diseases; periodontitis; tooth loss; inflammation; diet; nutrition; oral health
Online: 17 November 2020 (14:44:20 CET)
Background: We aimed to assess the association between DII and PD and the mediation effect of DII in the association of PD with systemic inflammation. Using the National Health and Nutrition Examination Survey (NHANES) 2009-2010, 2011-2012 and 2013-2014, participants that received periodontal exam and provided dietary recall data were included. The inflammatory potential of diet was calculated via DII. Periodontitis was defined according to the 2012 case definition. The clinical outcomes of interest were mean periodontal probing (PPD), mean clinical attachment loss (CAL) and thresholds of PPD and CAL. White blood cells (WBC), segmented neutrophils and C-reactive protein (CRP) were used as proxies for systemic inflammation. The periodontal measures were regressed across DII values using adjusted multivariate linear regression. Adjusted mediation analysis appraised the influence of DII in the association of periodontitis and systemic inflammation. 10,178 participants were included. DII was significantly correlated with mean PPD, mean CAL, thresholds of PPD and CAL, WBC, segmented neutrophils and DII (p<0.01). A linear regression logistic adjusted for multiple confounding variables confirmed the association between DII and mean PPD (B = 0.02, Standard Error [SE]: 0.02, p<0.001) and CAL (B = -0.02, SE: 0.01, p<0.001). The association of mean PPD and mean CAL with both white blood cells and segmented neutrophils were mediated by DII (from 2.1 to 3.5%, p<0.001). In the 2009-2010 subset, the association of mean CAL with serum CRP was mediated by DII (52.0%, p<0.01). In conclusion, inflammatory diet and PD may be associated. Also, the inflammatory diet significantly mediated the association of leukocyte counts and systemic inflammation with periodontitis.
ARTICLE | doi:10.20944/preprints201908.0285.v1
Subject: Medicine And Pharmacology, Dentistry And Oral Surgery Keywords: oral health , pre-diabetic, diabetic, oral systemic, screening, H1A1c, Findrisk , periodontal
Online: 27 August 2019 (11:58:44 CEST)
Pre-diabetes is a serious health condition where blood sugar levels are higher than normal, but not high enough yet to be diagnosed as type 2 diabetes. Pre-diabetes puts one at an increased risk of developing type 2 diabetes and heart disease Methodology: A cross-sectional study was carried out on 384 patients aged 20-70 years old, attending the dental clinics to assess the risk for diabetes, using the FINDRISC questionnaire, HbA1c blood test and a periodontal examination. Results: The mean age of participants was 38.90±10.74. 32.3% were categorized as no risk, 46.6% low risk, while 19% and 2.1% moderate and high risk of developing diabetes respectively. Tests for serum HbA1c Level showed 46.1 % had normal HbA1c followed by 18.0% and 3.6 % were pre-diabetic and diabetic respectively. 19.3% of participants had periodontal pockets measuring more than 4mm and 15.9% measuring more than 6mm. Conclusion: The study has proven to be useful in identifying patients at high-risk of developing diabetes. Controlling and managing periodontal disease could be a new aspect to include in the standards for diabetes care. Dental settings could be a successful platform to carry out the screening and risk stratification of pre-diabetic patients.
ARTICLE | doi:10.20944/preprints202306.0040.v1
Subject: Medicine And Pharmacology, Dentistry And Oral Surgery Keywords: Fucoidan-Chitosan; Injectable Hydrogel; osteogenic potential; periodontal intrabony defects; human experimental trial
Online: 1 June 2023 (05:48:04 CEST)
Periodontal diseases significantly impact about half of the global population, and their treatment often encompasses relieving symptoms as well as regenerating the destroyed tissues. Revolu-tionary research in the management of periodontal disease includes biomaterials, a boon to re-generative dentistry owing to their excellent biological properties, non-toxic, an-ti-inflammatory, biocompatible, biodegradable, and adhesion. This study aimed to fabricate an injectable fucoidan containing chitosan hydrogel and prove its effectiveness in periodontal bone regeneration. The injectable hydrogel was prepared using the sol-gel method and loaded into 2ml syringes. 40 periodontitis patients with bony defects were recruited and randomized into two groups, to re-ceive fucoidan-chitosan hydrogel and concentrated growth factor, respectively. Customized acrylic stents were used to guide the hydrogel placement into the defect site. Post-surgical changes in clinical parameters were assessed at 3, 6 and 9 months to appreciate the soft & hard tissue changes using repeated measures analysis of variance and Bonferroni’s posthoc test. Significance was kept at 5%. The fucoidan-chitosan hydrogel exhibited significantly lower probing depth values and a higher mean reduction in clinical attachment level as compared to the CGF group at the end of 3 and 6 months (p<0.05). The mean defect fills in the fucoidan-chitosan group was 1.20 at the end of 9 months (p<0.001). The presence of fucoidan in the hydrogel significantly contributed to bone re-generation in humans, thus strengthening its potential in tissue engi-neering. Fucoidan- Chitosan will be a promising biomaterial for bone tissue regeneration.
Subject: Chemistry And Materials Science, Biomaterials Keywords: transforming growth factor β3; chitosan sponge; human periodontal ligament cells; osteogenic differentiation
Online: 11 September 2019 (13:42:18 CEST)
Abstract: Periodontal disease is the main reason for tooth loss in adults. Tissue engineering and regenerative medicine are the advanced technologies used to manage soft and hard tissue defects caused by periodontal disease. We developed a transforming growth factor-β3 chitosan sponge (TGF-β3/CS) to repair periodontal soft and hard tissue defects. We investigated the proliferation and osteogenic differentiation behaviors of primary human periodontal ligament stem cells (hPDLSCs) to discuss the bioactivity and application of TGF-β3 in periodontal disease. We separately used Calcein-AM/PI double-labeling or CM-Dil-labeling coupled with fluorescence microscopy to trace the survival and function of the cells after implantation in vitro or in vivo. The mineralization of osteogenic differentiated hPDLSCs was confirmed by measuring ALP activity and calcium content. The levels of COL I, ALPL, TGF-βRI, TGF-βRII, and Pp38/t-p38 were tested using Western blot to explore the mechanism of bone repair prompted by TGF-β3. When hPDLSCs were inoculated with different concentrations of TGF-β3/CS (62.5–500 ng/mL), ALP activity was the highest in TGF-β3 (250 ng/mL) group after seven days (P < 0.05 vs. control); the calcium content in each group increased significantly after 21 and 28 days (P < 0.001 vs. control). The best result was achieved in the TGF-β3 (500 ng/mL) group. All results showed that TGF-β3/CS can promote osteogenic differentiation of hPDLSC and may be involved in the p38 MAPK signaling pathway. TGF-β3/CS has the potential for application in the repair of incomplete alveolar bone defects.
ARTICLE | doi:10.20944/preprints201902.0131.v1
Subject: Medicine And Pharmacology, Dentistry And Oral Surgery Keywords: Platelet-rich fibrin, A-PRF, Gingival graft harvesting, Healing, Periodontal plastic surgery
Online: 14 February 2019 (10:29:29 CET)
This study aimed to investigate the healing effect of advanced platelet-rich fibrin (A-PRF) clot membranes in the reduction of palatal wounds resulting from free gingival graft (FGG) harvesting, in the re-epithelization rate and in the pain experience after surgery. Twenty-five patients requiring soft tissue augmentation (gingival recession coverage or keratinized gingiva augmentation) participated in this prospective randomized clinical study. After FGG harvesting, the test group (n=14) received A-PRF clot membranes at the palatal wound and the control group (n=11) a gelatin sponge. Epithelialization rate of the palatal wound, wound healing area, correspondent percentage of reduction and post-surgical pain experience were assessed. The follow-up period was 90 days. There was a significantly higher reduction of the palatal wound area in the A-PRF group vs. the control group, at 7 (p<0.001), 14 (p=0.009) and 30 days (p<0.001) follow-up. The maximum difference between groups was attained at 30 days (91.5% for A-PRF vs. 59.0% for the control group). At 14 days a significant difference in the proportion of patients showing total epithelization was found: 64.3% for A-PRF vs. 9.1% for the control group (p=0.012). At 90 days, both groups showed total recovery. Overall, the control group experienced a higher level of pain and discomfort until the 14th day, being significantly higher on the second day (p=0.013). The results suggest that A-PRF membranes haste the healing process by promoting a greater reduction along the recovery period and an apparent less painful postoperative period.
ARTICLE | doi:10.20944/preprints201902.0123.v1
Subject: Medicine And Pharmacology, Dentistry And Oral Surgery Keywords: Medical Illiteracy, Public Awareness, Periodontal Diseases, Global Burden of Disease, Google Trends
Online: 13 February 2019 (15:54:04 CET)
Background: The progression of periodontal diseases at national Portuguese level and its public awareness are of great interest, mainly due to the high burden of periodontitis. Objectives: To evaluate the prevalence progression of periodontal diseases in Portugal and correspondent public awareness, between 2004 and 2017, by using data from the Global Burden of Disease (GBD), Directorate-General of Health (DGH) and Google® Trends (GT). Methods: For the period 2004-2017, Portuguese national data of periodontal diseases prevalence were searched in the Institute for Health Metrics and Evaluation of GBD and DGH and for public awareness, GT comparison tool between Portuguese words for “Periodontitis”, “Gingivitis”, “Gums” and “Periodontal disease” trends was used. Results: For the period 2004-2017, the overall prevalence of periodontitis slightly increased from 11.3% to 11.7%. During that period the GT search term “Gums” (“Gengivas”) was the most relevant. It increased steadily over time while the search term “Periodontal disease” (“Doença periodontal”) decreased, being these search trends significantly correlated (
ARTICLE | doi:10.20944/preprints201810.0570.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: bone resorption; butyric acid; HDAC inhibitor; osteoblasts; osteoprotegerin/RANKL; periodontal/root canal pathogens
Online: 24 October 2018 (11:21:42 CEST)
Butyric acid as a histone deacetylase (HDAC) inhibitor was produced by a number of periodontal and root canal microorganisms (such as Porphyromonas, Fusobacterium etc.). Butyric acid may affect the biological activities of periodontal/periapical cells such as osteoblasts, periodontal ligament cells etc., and thus affect periodontal/periapical tissue destruction and healing. The purposes of this study were to study the toxic effects of butyrate on matrix and mineralization markers’ expression of MG-63 osteoblasts. Cell viability and proliferation were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Cellular apoptosis and necrosis were analyzed by propidium iodide/Annexin V flow cytometry. Protein and mRNA expression of OPG, and RANKL were analyzed by western blotting and RT-PCR. OPG, soluble RANKL (sRANKL), 8-isoprostane, pro-collagen I, MMP-2, osteonectin (SPARC), osteocalcin and osteopontin secretion into culture medium were measured by enzyme-linked immunosorbant assay. Histone H3 acetylation levels were evaluated by immunofluorescent staining (IF) and western blot. We found that butyrate induced morphologic changes of growing MG-63 cells, with bigger and flattened in appearance. Butyrate activated histone H3 acetylation of MG-63 cells. Exposure of MG-63 cells to butyrate partly decreased cell number with no marked increase in apoptosis and necrosis. Butyrate stimulated RANKL protein expression, whereas it inhibited OPG protein expression. Butyrate also inhibited the secretion of OPG in MG-63 cells, whereas sRANKL level was below detection limit. Butyrate stimulated 8-isoprostane, MMP-2 and osteopontin secretion, but not procollagen I, osteonectin, osteocalcin in MG-63 cells. In conclusion, butyric acid generated by periodontal and root canal microorganisms may potentially induce bony destruction and impair bone repair by alteration of OPG/RANKL expression/secretion, 8-isoprostane, MMP-2, and osteopontin secretion, and affect cell proliferation. These effects are possibly related to increased histone acetylation. These events are important in the pathogenesis of periodontal and periapical destruction.
REVIEW | doi:10.20944/preprints202306.0101.v1
Subject: Dentistry And Oral Surgery, Medicine And Pharmacology Keywords: Quorum sensing; Autoinducer-2 (AI-2); Acetyl homoserine lactones (AHL); Periodontal diseases; Oral Biofilm
Online: 1 June 2023 (13:54:31 CEST)
Oral diseases remain a major health problem worldwide, with the World Health Organisation reporting that oral health neglect affects almost half of the world’s population. Quorum sensing molecules (QSMs) influence oral biofilms in various ways with knowledge of direct oral QSM-host interaction being limited, and such studies could provide more insight into the cross-kingdom communication occurring during oral disease development. This review aims to explore the literature on oral QSM-host interaction and to highlight areas of advancement in this field. QSM CSP-1 produced by Gram-positive oral bacteria was found to interact with T2R receptors, activating NF-kB signalling and leading to remodeling of the cytoskeleton. AI-2 in the oral cavity was found in various studies to elicit an inflammatory response in specific oral cells. Overall AHL detection methods remain an area for development, through which greater understanding of oral QSMs’ influence on host cells can be achieved. In conclusion, from the current literature it can be inferred that that QSMs are utilised by host cells to detect bacterial presence and in the majority of cases elicit an immune response towards the environmental QSMs. This may provide a base to target QSMs as novel treatment of oral diseases.
ARTICLE | doi:10.20944/preprints202305.0653.v1
Subject: Biology And Life Sciences, Life Sciences Keywords: GDF15; Orthodontic tooth movement; Periodontal ligament fibroblasts; Osteoblast differentiation; Mechanobiological response; Inflammation; Osteoclast Activation
Online: 9 May 2023 (12:33:14 CEST)
Periodontal ligament fibroblasts (PdLFs) exert important functions in oral tissue and bone remodeling following mechanical forces, which are specifically applied during orthodontic tooth movement (OTM). Located between the teeth and the alveolar bone, mechanical stress activates the mechanomodulatory functions of PdLFs including the regulation of local inflammation and activation of further bone-remodeling cells. Previous studies suggested the growth differentiation factor 15 (GDF15) as important pro-inflammatory regulator during the PdLFs mechanoresponse. However, the precise mechanism remains to be clarified, as GDF15 may act both intracrine and by receptor binding, potentially also in an autocrine manner. The extent to which PdLFs are susceptible to extracellular GDF15 has not yet been investigated. Thus, our study aims to examine the influence of GDF15 exposure on cellular properties of PdLFs and their mechanoresponse, which seems particularly relevant regarding disease- and aging-associated elevated GDF15 serum levels. Therefore, in addition to investigating potential GDF15 receptors, we analyzed its impact on proliferation, survival, senescence, and differentiation of human PdLFs, demonstrating a pro-osteogenic effect upon long-term stimulation. Furthermore, we detected an altered force-related inflammation and impaired osteoclast differentiation. Overall, our data suggest a major impact of extracellular GDF15 on PdLFs differentiation and their mechanoresponse.
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: periodontal disease; non-alcoholic fatty liver disease; exercise; clinical trial; oral microbiota; saliva components
Online: 14 January 2021 (13:13:47 CET)
Exercise can be hypothesized to play an important role in NAFLD treatment by changing the oral bacterial flora and in the mechanism underlying periodontal disease. We performed salivary component analysis before and after an exercise regimen, and genome analysis of the oral bacterial flora to elucidate the underlying mechanism. Obese middle-aged men with NAFLD and periodontal disease were allocated to 12-week exercise (n=49) or dietary restriction (n=21) groups. We collected saliva to compare the oral microflora; performed predictive analysis of metagenomic functions; and measured the salivary immunoglobulin A, cytokine, bacterial lipopolysaccharide (LPS), and lactoferrin concentrations. The exercise group showed improvements in clinical indices of oral environment. Salivary component analysis revealed significant reductions in LPS, and lactoferrin during the exercise regimen. Diversity analysis of oral bacterial flora revealed higher alpha- and beta-diversity after the exercise regimen. Analysis of the microbial composition revealed that the numbers of Campylobacter (+83.9%), Corynebacterium (+142.3%), Actinomyces (+75.9%), and Lautropia (+172.9%) were significantly higher and that of Prevotella (−28.3%) was significantly lower. The findings suggest that an exercise regimen improves the oral environment of NAFLD patients by increasing the diversity of the oral microflora and reducing the number of periodontal bacteria that produce LPS and its capability.
ARTICLE | doi:10.20944/preprints202005.0308.v1
Subject: Medicine And Pharmacology, Pharmacology And Toxicology Keywords: Oral health care products; cyclooxygenase; lipoxygenase; periodontal disease; Candida albicans; Candida glabrata; medicinal herbs
Online: 19 May 2020 (03:45:56 CEST)
Background: Given the increasing request for natural pharmacological molecules, this study assessed the antimicrobial capacity of Pistacia lentiscus L. essential oil (PLL-EO) obtained from the leaves of wild plants growing in North Sardinia (Italy), toward a wide range of periodontal bacteria and Candida including laboratory and clinical isolates sp., together with its anti-inflammatory activity and safety; Methods: PLL-EO was screened by gas chromatography / mass spectrometry. The minimal inhibitory concentration (MIC) was determined. The anti-inflammatory activity was measured by cyclooxygenase (COX 1/2) and lipoxygenase (LOX) inhibition while the antioxidant capacity was determined electro-chemically and by the MTT assay. The WST-1 assay was used to ascertain cytotoxicity toward four line of oral cells; Results: According to the concentrations of terpens, PLL-EO is a pharmacologically active phytocomplex. MICs against periodontal bacteria ranged between 3.13 and 12.5 µg/ml, while against Candida sp. were between 6.25 and 12.5 µg/ml. Oxidation by COX 1/2 and LOX was inhibited by 80% and 20% µg/mL of the oil respectively. Antioxidant activity seemed negligible, and no cytotoxicity arose; Conclusions: PLL-EO exhibits a broad-spectrum activity against periodontal bacteria and Candida, with an interesting dual inhibitory capacity toward COX2 and LOX inflammatory enzymes and without side effects against oral cells.
ARTICLE | doi:10.20944/preprints202306.0037.v1
Subject: Medicine And Pharmacology, Dentistry And Oral Surgery Keywords: tricalcium silicate nanoparticle-containing cement (NPC); mineral trioxide aggregate (MTA); human periodontal ligament fibroblasts (HPLFs)
Online: 1 June 2023 (05:30:27 CEST)
A tricalcium silicate nanoparticle-containing cement (NPC) was developed to overcome the disadvantages of existing mineral trioxide aggregate (MTA) dental materials. This study aimed at evaluating the effects of NPC on the osteogenic differentiation of human periodontal ligament fibroblasts (HPLFs) in vitro, and on the healing of furcal perforations created experimentally in rat molars in vivo, in comparison to MTA. The in vitro studies performed the following assays; pH measurement using a pH meter, the release of calcium ions using a calcium assay kit, cell attachment and morphology using SEM, cell proliferation using a coulter counter, marker expression using quantitative reverse transcription polymerase chain reaction (qRT-PCR) and cell mineralized deposit formation using Alizarin Red S (ARS) staining. In the in vivo studies, MTA and NPC were used to fill the rat molar perforations. Rat molars were processed at 7, 14 and 28 days for analysis of inflammatory processes using hematoxylin and eosin (HE) staining, immunohistochemical staining of Runx2 and tartrate-resistant acid phosphate (TRAP) staining. The results demonstrate that the nanoparticle size distribution of NPC is critical for osteogenic potential at an earlier stage compared to MTA. Further studies are required to elucidate the mechanism of action of NPC in osteogenic differentiation.
ARTICLE | doi:10.20944/preprints202101.0090.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: periodontal disease; periodontitis; early tooth loss; predictive model; risk factors; oral health; public health; epidemiology
Online: 5 January 2021 (13:03:13 CET)
The aim of this study was to develop and validate a predictive early tooth loss multivariable model for periodontitis patients before periodontal treatment. A total of 544 patients seeking periodontal care at a university dental hospital were enrolled in the study. Teeth extracted after periodontal diagnosis and due to periodontal reasons were recorded. Clinical and sociodemographic variables were analyzed, considering the risk of short-term tooth loss. This study followed the Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis (TRIPOD) guidelines for development and validation, with two cohorts considered as follows: 455 patients in the development phase and 99 in the validation phase. As a result, it was possible to compute a predictive model based on tooth type and clinical attachment loss. The model explained 25.3% of the total variability and correctly ranked 98.9% of the cases. The final reduced model area under the curve (AUC) was 0.809 (95% Confidence Interval (95% CI): 0.629 - 0.989) for the validation sample and 0.920 (95% CI: 0.891 - 0.950) for the development cohort. The established model presented adequate prediction potential of early tooth loss due to periodontitis. This model may have clinical and epidemiologic relevance towards the prediction of tooth loss burden.
ARTICLE | doi:10.20944/preprints201909.0345.v1
Subject: Social Sciences, Psychology Keywords: action planning; coping planning; health education; oral care behavior; periodontal disease; theory of planned behavior
Online: 30 September 2019 (08:15:24 CEST)
Background: Strengthening adherence to self-care behaviors in patients with periodontal disease (PD) and reducing plaque index is crucial for improving PD treatment. We evaluated the effectiveness of a theory of planned behavior (TPB)-based health education intervention involving planning strategy on self-care behaviors in patients with PD. Methods: A randomized controlled trial was conducted; 158 and 139 patients comprised the experimental group (EG) and control group (CG), respectively. Both groups received a leaflet, and the EG also received a planning intervention, which was a brief one-on-one counseling session with a planning sheet. Data were collected using a self-administered questionnaire. Results: Between-group comparisons of TPB measures revealed significant differences in all domains when controlling for baseline covariates. The EG exhibited significantly higher levels of action and coping planning than the CG at 2-week follow-up (effect size (ES) = 5.54 and 5.57, respectively) and 6-week follow-up (ES = 5.66 and 5.66, respectively). Between-group differences in changes of brushing behaviors increased significantly. More frequent use of dental floss was observed in the EG than in the CG at 2-week and 6-week follow-ups (24.7% and 22.8%, respectively). Conclusions: The intervention involving planning strategy effectively promoted adherence to self-care behaviors in patients with PD.
REVIEW | doi:10.20944/preprints202008.0557.v1
Subject: Medicine And Pharmacology, Dentistry And Oral Surgery Keywords: transplantation; dental implant; marginal bone loss; implant failure rate; systematic review; periodontitis; periodontal diseases; oral health
Online: 25 August 2020 (13:45:34 CEST)
This systematic review investigates the failure rate and marginal bone loss (MBL) of dental implants placed in Solid-organ transplant (SOT) patients compared to healthy controls. Three databases (PubMed, Web of Sciences and the Cochrane Library) were searched up to June 2020 (PROSPERO CRD42019124896). Case-control and cohort studies reporting data failure rate and marginal bone loss (MBL) of dental implants placed in SOT patients were included. The risk of bias of observational studies was assessed through the Newcastle-Ottawa Scale (NOS). Four case-control studies fulfilled the inclusion criteria, all of low risk of bias. Meta-analyses revealed consistently lower implant failure rate than control populations at patient and implant levels. SOT patients had a significant difference of -18% (p-value <0.001) of MLB towards healthy patients. SOT status poses no serious threat to implant survival. Overall, this group of patients presented lower levels of dental implant failure rate and marginal bone loss compared to otherwise healthy patients. Further intervention trials with wider sample size and longer follow-ups are necessary to confirm these summary results.
REVIEW | doi:10.20944/preprints201901.0199.v1
Subject: Medicine And Pharmacology, Dentistry And Oral Surgery Keywords: periodontal regeneration; aggressive periodontitis; deproteinized bovine bone; enamel matrix derivatives (Emdogain®); guided tissue regeneration (GTR)
Online: 21 January 2019 (08:58:50 CET)
The aim of this article is to evaluate and compare, retrospectively, the efficacy of two regenerative periodontal procedures in patients suffering from aggressive periodontitis (AgP). Twenty-eight patients were diagnosed with AgP, suffering from multiple intra-bony defects (IBD); that were treated by one of two regenerative modalities of periodontal therapy randomly assigned to each patient: a. guided tissue regeneration (GTR) or b. an application of enamel matrix derivatives (EMD) combined with DBX. The monitoring of the treated sites included recordings of probing depth (PD), clinical attachment level (CAL), and gingival recession. Pre-treatment and follow-up (up to 10 years from the surgery) recordings were analyzed statistically within and between groups. A significant reduction was shown at time on PD and CAL values, however, not between subject groups. CAL values decreased in all sites. At EMD group (44 sites) CAL gain was 1.92 mm (±1.68) from pre-treatment to follow-up (p<0.001) and at the GTR group (12 sites) CAL gain of 2.27 (±1.82) mm. In conclusion, 1-10 years observations have shown that surgical treatment of AgP patients by either GTR or by application of EMD/DBX results in similar successful clinical results.
ARTICLE | doi:10.20944/preprints201704.0016.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: periodontitis; the periodontal ligament stem cells; the nuclear factor-erythroid 2-related factor 2; oxidative stress; apoptosis
Online: 4 April 2017 (08:58:13 CEST)
The present study aimed to analyze novel mechanisms underlying Nrf2-mediated anti-apoptosis in periodontal ligament stem cells (PDLSCs) in the periodontitis oxidative microenvironment. We created an oxidative stress model with H2O2-treated PDLSCs. Herein, we used real-time PCR, western blotting, TUNEL staining, fluorogenic assay and transfer genetics to confirm the degree of oxidative stress and apoptosis as well as the Nrf2 function. Surprisingly, we demonstrated that with up-regulated ROS and MDA levels, the effect of oxidative stress was obvious under H2O2 treatment. Anti-oxidative molecules were changed after the H2O2 exposure, whereby the anti-oxidative signaling of Nrf2 was activated with the increase of its downstream effectors, HO-1, NQO1 and γ-GCS. Additionally, the apoptosis levels gradually increased with oxidative stress and changes in the caspase-9, caspase-3, Bax and c-Fos levels, but not with caspase-8 and down-regulated Bcl-2. The enhanced antioxidant effect could not resist the occurrence of apoptosis. Furthermore, Nrf2 overexpression effectively improved the anti-oxidative levels and increased cell proliferation. At the same time, overexpression effectively restrained TUNEL staining and decreased the molecular levels of caspase-9, caspase-3, et al, but not that of caspase-8. By contrast, silencing the expression Nrf2 levels had the opposite effect. Collectively, Nrf2 alleviates PDLSCs via its effects on anti-oxidative and anti-intrinsic apoptosis by the activation of anti-oxidative enzymes.
REVIEW | doi:10.20944/preprints202102.0455.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: essential oils; water extracts; ethanol extracts; periodontal bacteria; Candida; natural antimicrobials; natural anti-inflammatory; Sardinian plants; pharmaceutical plants
Online: 22 February 2021 (10:53:13 CET)
There is an increasing interest in revisiting plants for drug discovery proving scientifically their role as remedies. Pistacia lentiscus (PL) is a wild-growing shrub rich in terpenoids, which are pharmacological appealing. The more recurrent components in the oil are represented by α-pinene, terpinene, caryophyllene, limonene, and myrcene. High concentration of polyphenols enriches the extracts. PL-extracts showed in vitro and in animal model strong anti-inflammatory and anti-oxidative activities. The anti-inflammatory activity mainly occurs due to inhibition of NF-kB pathway or directly toward the proinflammatory cytokines, or arachidonic acid cascade against COX-2 and LOX. The antimicrobial activity of PL essential oil and extracts includes among others Staphylococcus aureus, Escherichia coli, periodontal bacteria and Candida sp.. In conclusion, the biological properties, and particularly the anti-inflammatory and anti-microbial capacity, propose PL as a new safe pharmaceutical agent.
ARTICLE | doi:10.20944/preprints201807.0321.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: MicroRNA; osteoprotegerin (OPG); orthodontic tooth movement (OTM); miR-3198; mechanical stresses; periodontal ligament cells (PDL cells); compression; tension
Online: 18 July 2018 (08:58:19 CEST)
Background: Osteoclastic bone resorption in the compression zone of periodontal ligament (PDL) plays a role in orthodontic tooth movement, and is regulated by the balance of RANKL and OPG. Compression downregulates OPG, conversely, tension upregulates OPG in PDL cells. However, the regulatory mechanism of OPG expression in PDL cells under different mechanical stresses remains unclear. Methods: To study microRNA (miRNA) expression profiles, compression (2g/cm2) or tension (15%-elongation) was applied to immortalized human PDL (HPL) cells, and miRNA was extracted. The miRNA expression was analyzed using a human miRNA microarray, and the changes of the miRNA expression were confirmed by real-time RT-PCR. In addition, miR-3198-mimic and -inhibitor were transfected into HPL cells to understand the resulting OPG expression and production. Results: Certain miRNAs were expressed differentially under compression and tension. Some miRNAs including miR-3198 were upregulated only by compression. Real-time RT-PCR confirmed that compression induced miR-3198, but tension reduced it, in HPL cells. miR-3198-inhibitor upregulated and miR-3198-mimic reduced OPG in HPL cells. miR-3198-inhibitor rescued the compression-mediated downregulation of OPG. On the other hand, miR-3198-mimic reduced OPG expression under tension. Conclusion: We conclude that miR-3198 is upregulated by compression and is downregulated by tension, suggesting that miR-3198 downregulates OPG in response to mechanical stress.
ARTICLE | doi:10.20944/preprints202210.0311.v1
Subject: Medicine And Pharmacology, Dentistry And Oral Surgery Keywords: Animal study; beagle dog; β-tricalcium phosphate (TCP); immunohistochemistry; micro computed tomography (CT); periodontal tissue engineering; periostin; recombinant human collagen peptide (RCP); scaffold material; 3-wall intrabony defect
Online: 20 October 2022 (12:24:49 CEST)
Recombinant human collagen peptide (RCP) is a recombinantly created xeno-free biomaterial enriched in RGD (arginine-glycine-aspartic acid) sequences, with good processability that is being investigated for regenerative medicine applications. Recently, the biocompatibility and osteogenic ability of β-TCP/RCP (RCP granules combined with β-tricalcium phosphate (TCP) submicron particles) were demonstrated. In the present study, β-TCP/RCP was implanted into experimental periodontal tissue defects (three-walled bone defect) created in beagle dogs to investigate tissue responses and subsequent regenerative effects. Micro computed tomography image analysis at 8 weeks postoperatively showed that the amount of new bone after β-TCP/RCP graft was significantly greater (2.2 fold, P<0.05) than that of the control (no graft) group. Histological findings showed that the transplanted β-TCP/RCP induced active bone-like tissue formation including TRAP-positive and OCN-positive cells as well as bioabsorbability. Ankylosis did not occur, and periostin-positive periodontal ligament-like tissue formation was observed. Histological measurements revealed that β-TCP/RCP implantation formed 1.7-fold more bone-like tissue and 2.1-fold more periodontal ligament-like tissue than the control, and significantly suppressed gingival recession and epithelial downgrowth (P<0.05). These results suggest that β-TCP/RCP is effective as a periodontal tissue regenerative material.