Therapeutic Potential of Chlorhexidine-Loaded Calcium Hydroxide-Based Intracanal Medications in Endo-Periodontal Lesions: An Ex Vivo and In Vitro Study.

Endo-periodontal lesions are challenging clinical situations where both the supporting tissues and the root canal of the same tooth are infected. In the present study, chlorhexidine (CHX)-loaded calcium hydroxide (CH) pastes were used as intracanal medications (ICMs). They were prepared and tested on pathogens found in both the root canal and the periodontal pocket. Exposure to 0.5% and 1% CHX-loaded ICMs decreased the growth of Porphyromonas gingivalis and was effective in eradicating or inhibiting an Enterococcus faecalis biofilm. CH was injected into the root canal of extracted human teeth immersed in deionized water. CHX-loaded ICMs resulted in the transradicular diffusion of active components outside the tooth through the apex and the lateral dentinal tubules, as shown by the release of CHX (from 3.99 µg/mL to 51.28 µg/mL) and changes in pH (from 6.63 to 8.18) and calcium concentrations (from 2.42 ppm to 14.67 ppm) after 7 days. The 0.5% CHX-loaded ICM was non-toxic and reduced the release of IL-6 by periodontal cells stimulated by P. gingivalis lipopolysaccharides. Results indicate that the root canal may serve as a reservoir for periodontal drug delivery and that CHX-based ICMs can be an adjuvant for the control of infections and inflammation in endo-periodontal lesions.

Bioactive Endodontic Hydrogels: From Parameters to Personalized Medicine.

Regenerative endodontic procedures (REPs) aim at recreating dental pulp tissue using biomaterials such as hydrogels. Their bioactivity is mostly related to the nature of biomolecules or chemical compounds that compose the endodontic hydrogel. However, many other parameters, such as hydrogel concentration, bioactive molecules solubility, and apex size, were reported to influence the reciprocal host-biomaterial relationship and hydrogel behavior. The lack of knowledge regarding these various parameters, which should be considered, leads to the inability to predict the clinical outcome and suggests that the biological activity of endodontic hydrogel is impossible to anticipate and could hinder the bench-to-bedside transition. We describe, in this review, that most of these parameters could be identified, described, and studied. A second part of the review lists some challenges and perspectives, including development of future mathematical models that are able to explain, and eventually predict, the bioactivity of endodontic hydrogel used in a clinical setting.

Shaping Ability of F6 SkyTaper®, Hyflex® EDM One File, and One Curve®: A Micro-computed Tomographic Evaluation in Curved Root Canals.

OBJECTIVE: The present study aimed to compare the shaping ability of the F6 SkyTaper® (F6S), HyFlex® EDM OneFile (HEDM), and One Curve® (OC) nickel-titanium single-file instruments using micro-computed tomography. METHODS: Fifty-two mesiobuccal roots of maxillary first molars, with a degree of curvature between 20° and 42°, were randomised into three experimental groups (n=15 per group): F6S, HEDM, and OC, and a non-instrumented control group (n=7). All specimens were scanned by micro-computed tomography before and after instrumentation. The following parameters were evaluated: preparation time, volume of dentine removed, cutting efficiency, unshaped surfaces, and canal transportation. Cutting efficiency was analysed using an ANOVA parametric test and Tukey's multiple comparison post hoc test. Other parameters were analysed using a non-parametric Kruskall-Wallis test followed by Dunn's multiple comparison post hoc test. RESULTS: No instrument separation occurred during instrumentation. No significant differences were found between the instrument groups with respect to all the parameters (p>0.05). All the instruments induced morphological changes in the root canal dentine (p<0.05) and tended to increase canal transportation toward the coronal portion of the root canals (p>0.05). CONCLUSION: All instruments were able to shape curved canals and preserve their original anatomy. Single-file endodontic procedures with these instruments can be used with comparable changes in the root canal shape with minimal transportation. (EEJ-2022-01-06).

Knowledge, Attitude, Access and Confidence in Evidence-based practice amongst French dental undergraduates: A transcultural adaptation and psychometrics analysis of French version of the KACE questionnaire.

OBJECTIVE: The aim of this study was to provide a reliable instrument to assess evidence-based practice (EBP) dimensions in French-speaking dental students. To do so, a transcultural adaptation into French of the self-administered KACE questionnaire (Knowledge, Attitude, Access and Confidence Evaluation) and the evaluation of its psychometric properties in a sample of French dental students and teachers were performed. The effects of individual and academic factors on student performance in the KACE were also investigated. METHOD: Teachers and fourth-year students completed once the translated KACE and fifth-year students completed twice the questionnaire before and after an epidemiology course. Cronbach's alpha coefficient analysis, Kruskal-Wallis and post hoc Dunn's tests, paired samples Wilcoxon tests and a generalised linear mixed model were performed to assess the psychometric properties (reliability, internal consistency, discriminant validity and responsiveness) of the questionnaire and to identify the factors associated with KACE scores, respectively. RESULTS: 186 participants completed the survey. Cronbach's alpha ranged from 0.06 to 0.48 for Knowledge, 0.21 to 0.59 for Attitude, 0.42 to 0.76 for Access and 0.82 to 0.93 for Confidence. The discriminant value and sensitivity of the French KACE revealed significant differences amongst students and teachers and accurately identified the effect the training course had on the students who had completed it. Preparing for a residency programme or having received add-on modules in science improved the students' performance in the test. Being female negatively impacted the KACE Confidence score. CONCLUSION: This version of the KACE is appropriate to assess EBP dimensions in French dental students. Academic background and gender may affect test performance.

How Adding Chlorhexidine or Metallic Nanoparticles Affects the Antimicrobial Performance of Calcium Hydroxide Paste as an Intracanal Medication: An In Vitro Study.

The aim of our study was to explore the potential value of metallic (Ag, Cu, and Zn) salts, polymer/metallic nanoparticles, and chlorhexidine (CHX) for improving the antimicrobial activity of calcium hydroxide (CH) against E. faecalis and C. albicans, associated with persistent endodontic infections. A first screening was performed by determining minimum inhibitory/bactericidal concentrations (MIC/MBC). Antimicrobial activity of the CH paste mixed with metallic salts, chitosan or cyclodextrin polymer metallic nanoparticles was compared to the antimicrobial activity of CH paste alone and CH + CHX using a time-kill kinetics assay. The effect of the antimicrobials on the rheological and the key mechanical properties were also examined. Copper and zinc were discarded because of their MIC/MBC values and silver because of its kill time curve profile. Except for a slower setting time after 24 h and a higher weight loss after 1 week of incubation, the mechanical behavior of the CH paste was unaffected by the addition of CHX. Polymeric/metallic nanoparticles failed to potentiate the antimicrobial effect of CH. By contrast, CHX increased this effect and thus could help eradicate E. faecalis associated with persistent root canal infections without altering the desired key physical properties of the CH paste.

Periodontal Diseases and COVID-19: A Scoping Review.

The aim of this scoping review was to present the existing literature regarding the relationship between periodontal diseases and coronavirus disease 2019 (COVID-19). The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) extension for scoping review guidelines was followed. Articles were retrieved from PubMed/MEDLINE and Scopus databases and screened to include studies relating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or COVID-19 to periodontal cells and/or tissues and/or diseases. Twenty-five papers were included; consisting of six reviews, seven original articles, six short reports, four letters to the editor, one commentary, and one case report. The articles were allocated to three different topics: (i) hypotheses on the relationship between periodontal diseases and COVID-19; (ii) risk factors and comorbidities common to periodontitis and COVID-19; (iii) periodontal manifestations of COVID-19. Certain molecules (angiotensin-converting enzyme-2, furin, cathepsin, TMPRSS2...) that are found at a high level in periodontal tissues, particularly in patients with periodontitis, are involved in the mechanism of entry of SARS-CoV-2 into cells. Periodontopathic bacteria could also play a direct role in the mechanism of entry of SARS-CoV-2 by cleaving the S-protein, and the cytokines produced during periodontitis could add to the cytokine storm found in the severe forms of COVID-19. It thus appears that the treatment of periodontitis, which allows a reduction in periodontopathic bacteria and of the local and systemic inflammation state, could be part of a strategy to prevent the development of severe forms of COVID-19.

How to select proper interdental brush size in periodontitis patients: Comparison of the reliability of two methods among novice and expert users.

PURPOSE: To compare two methods used by novice and expert operators for selecting interdental brush (IDB) size for periodontitis patients: (1) sequential testing or (2) using a color-coded taper tip device (CTD) corresponding to color-coded brush sizes. METHODS: Six operators, one experienced and five dental students, employed both methods to determine the IDB with best fit for 204 interdental spaces in 34 periodontitis patients. The percentage of agreement and the inter-methods reliability was evaluated. The influence of anatomical features on differences between the operators or method was also investigated. RESULTS: Moderate to substantial correlation was found between the two methods but the reliability was stronger when different operators used the same method, irrespective of the method, than when they used a different method. Among the anatomical factors studied, only sites in molar regions were associated with significant differences. CLINICAL SIGNIFICANCE: Use of a dedicated color-coded taper tip may be an alternative to the fastidious sequential testing of different IDB in selecting best-fit IDB diameter for periodontal patients with moderate to broad interdental spaces.

Antibiotic Use in Periodontal Therapy among French Dentists and Factors Which Influence Prescribing Practices.

The aim of the present survey is to investigate the use of antibiotics during periodontal therapy among French dentists with a focus on exploring potential differences between various groups of practitioners. A self-administered questionnaire was distributed to different groups of practitioners including members of (i) the French Society of Periodontology and Implantology; (ii) the College of University Teachers in Periodontology and, (iii) private practitioners participating in the French general dental practice-based research network. 272 questionnaires were included in the analysis. Prescription patterns were globally in line with the current recommendations. Systemic antibiotics are most frequently used as a first-line therapy in necrotizing periodontitis (92%) and aggressive periodontitis (53.3% to 66.1%). However, malpractice still exists, including in the management of periodontal abscesses. Antibiotics are prescribed (i) less frequently for periodontal abscesses and (ii) more frequently for generalized aggressive periodontitis by members of the periodontal society and University college (p < 0.05). Amoxicillin (59.9%) and the amoxicillin + metronidazole (59.6%) combination were the most frequently prescribed molecules. Providing a high number of periodontal treatments per week, being more recently graduated, having a post-graduate certificate in periodontology and holding or having held an academic position/hospital practice were all factors associated with a better knowledge of and/or more adequate antibiotic use.

Antimicrobial effect and physical properties of an injectable "active oxygen" gel for the treatment of periodontitis.

PURPOSE: To evaluate an injectable gel, recently proposed for the controlled release of "active oxygen" in periodontal pockets, compared to an antibiotic or an antiseptic gel, respectively. METHODS: The antimicrobial activity, injectability, texture properties, swelling and water uptake of the gels were studied. RESULTS: The "active oxygen" gel showed a bactericidal effect comparable to the two commercially available drug products (containing minocycline or chlorhexidine) on anaerobic periodontal pathogens and did not seem to affect aerobic strains. The gel was easy to inject and stable in an aqueous medium for several days. Texture analysis revealed potential gel fragility. CLINICAL SIGNIFICANCE: The investigated gel for local delivery of oxygen can help to selectively eradicate anaerobic bacteria associated with periodontitis and promote the recovery of a healthy-compatible oral flora.

Awareness and practices of general practitioners towards the oral-systemic disease relationship: A regionwide survey in France.

RATIONALE, AIM, AND OBJECTIVE: "Periodontal medicine" is based on evidence of interactions between periodontal disease and overall health. The aim of the present study was to assess awareness of oral-systemic disease relationship among French general practitioners (GPs) and clarify how this influences their practices in a wider effort to better integrate oral health concerns into global health care delivery. METHOD: GPs registered in the north of France were invited to complete an online self-administered questionnaire through local divisions of the French Medical Board. The questionnaire was divided into four sections: socio-demographic aspects, knowledge, practices, and an overview. RESULTS: The questionnaire was completed by 253 GPs. Among these, 75% were aware of the association between periodontitis (PD) and diabetes, and 53% to 59% were aware of the impact of PD on cardiovascular diseases, inflammatory bowel diseases, and respiratory infections. Few GPs identified PD as a possible risk factor of rheumatoid arthritis and Alzheimer disease (35.18% and <15%, respectively); 74.31% of GPs reported never asking their patients about their periodontal health. However, a personal history of PD and professional experiences seem to influence the medical practices of GPs to include oral examination. GPs largely self-rated their knowledge of the oral-systemic disease connection as being insufficient and were favourable to completing an up-to-date training course (86.56%). CONCLUSION: French GPs' knowledge about the association of PD with systemic diseases seems to be fair, but discrepancies in their daily clinical routine were found. Promisingly, a positive attitude was observed towards improving their knowledge of oral-systemic diseases link. These results indicate the importance to reinforce collaboration between medical doctors and oral health care specialists.