Scanning Electron Microscopy Evaluation of Dental Root Resorption Associated With Granuloma

Photodynamic Suppression of Enterococcus Faecalis in Infected Root Canals with Indocyanine Green, TroloxTM and Near-Infrared Light

Recently, our group showed that additional supplementation of Trolox™ (vitamin E analogue) can significantly enhance the antimicrobial photodynamic effect of the photosensitizer Indocyanine green (ICG). Up to now, the combined effect has not yet been investigated on Enterococcus faecalis in dental root canals. In the present in vitro study, eighty human root canals were inoculated with E. faecalis and subsequently subjected to antimicrobial Photodynamic Therapy (aPDT) using ICG (250, 500, 1000 µg/mL) and near-infrared laser light (NIR, 808 nm, 100 Jcm-2). Trolox™ at concentrations of 6 mM was additionally applied. As a positive control, irrigation with 3% NaOCl was used. After aPDT, root canals were manually enlarged and the collected dentin debris was subjected to microbial culture analysis. Bacterial invasion into the dentinal tubules was verified for a distance of 300 µm. aPDT caused significant suppression of E. faecalis up to a maximum of 2.9 log counts (ICG 250 µg/mL). Additional application of TroloxTM resulted in increased antibacterial activity for aPDT with ICG 500 µg/mL. The efficiency of aPDT was comparable to NaOCl-irrigation inside the dentinal tubules. In conclusion, ICG significantly suppressed E. faecalis. Additional application of TroloxTM showed only minor enhancement. Future studies should also address the effects of TroloxTM on other photodynamic systems.

Root Canal Configuration and Its Relationship with Endodontic Technical Errors and Periapical Status in Premolar Teeth of a Saudi Sub-Population: A Cross-Sectional Observational CBCT Study

Endodontic technical errors are the foremost cause of treatment failure. A thorough understanding of root canal configuration (RCC) is essential to prevent these iatrogenic errors. This study used CBCT images to determine the association between root canal configuration, endodontic technical errors, and periapical status. CBCT images of 101 patients, including total of 212 obturated premolars (256 canals) were assessed. RCCs were classified according to the Vertucci system. The presence of endodontic errors and periapical lesions associated with each RCC was noted. Presence or absence of coronal restoration and its association with periapical radiolucency was recorded. The most frequent RCC was Type I (199 cases; 77.73%), followed by Type II (26 cases; 10.15%), Type IV (22 cases; 8.59%), Type V (4 cases; 1.56%), Type III (4 cases; 1.56%), and Type VI (1 case; 0.39%). Under-filling and non-homogeneous filling were the most common technical errors. Prevalence of periapical radiolucency was 81% in the presence of technical errors. The absence of coronal restoration caused apical lesions in 93% of cases. The frequency of endodontic technical errors increased as the root canal configurations became more complex. Periapical lesions occurred more often in teeth with endodontic errors and/or absent coronal restoration.

Diagnostic Accuracy of Pulp Vitality Tests and Pulp Sensibility Tests for Assessing Pulpal Health in Permanent Teeth: A Systematic Review and Meta-Analysis

The current systematic review and meta-analysis was carried out to compare the diagnostic accuracy of pulp vitality and pulp sensibility tests in assessing pulpal health. PubMed/MEDLINE, Cochrane Central Register of Controlled Trials, Web of Science, Google Scholar and Open Grey databases were searched and after assessing eligibility criteria the data were extracted. True-positive, false-positive, true-negative, false-negative, sensitivity and specificity values were extracted or calculated if not presented. Quality of studies was evaluated based on the QUADAS 2 tool. Meta-analysis was performed in MetaDTA (v2.0; Shinyapps, RStudio PBC, Boston, MA, USA) and Review Manager 5.3 (RevMan web; The Cochrane Collaboration, London, UK). Ten articles were included for qualitative synthesis and five for meta-analysis. The pooled diagnostic odds ratio for pulse oximeter (PO), electric pulp tester (EPT), cold test (CT) and heat test (HT) was 628.5, 10.75, 17.24 and 3.47, respectively. Pairwise comparison demonstrated a higher pooled mean sensitivity and specificity with PO compared with EPT. Comparison between PO and CT and between PO and HT also demonstrated a higher pooled mean sensitivity and specificity for PO. Summary points on receiver operating characteristic curves confirmed the ability of PO to correctly screen negatives in presenting patients as compared to EPT, CT and HT but no study was rated as good on quality assessment. PO can be considered as the most accurate diagnostic method as compared to EPT, CT and HT. This review provides information about the reliability and diagnostic accuracy of using pulp vitality and sensibility tests for assessing pulp status.

The Application of Nano Silver Argitos as a Final Root Canal Irrigation for the Treatment of Pulpitis and Apical Periodontitis. In Vitro Study

BACKGROUND

Endodontic treatment of various forms of pulpitis with variations of root canal system anatomy should be performed with high quality. The use of various antibacterial agents is aimed at maintaining the success of endodontic treatment. The aim of this study was to evaluate the penetration and fixation of the nano-silver solution on the dentinal surface during endodontic treatment.

MATERIALS AND METHODS

the study was carried out on 70 extracted single-rooted teeth, randomly divided into two groups. In the teeth of the first group, the smear layer was removed after canal preparation with 17% EDTA solution; in the second group, the smear layer was not removed. In both groups, for the final treatment of the canal, a colloidal 1% solution of нанo серебра nanosilver was used. Samples were cut and prepared for analysis using micro-CT, scanning electron microscopy (SEM), X-ray microanalysis and energy dispersive spectrometry (elemental mapping).

RESULTS

in 100% of cases in groups of teeth with a preserved smear layer, the ability of a 1% colloidal solution of nanosilver with particles of 1-2 nm to be fixed on dentin with a removed and preserved smear layer and to leave a film on the dentinal surface was established. In the samples with removed smear layer, silver was found in 73.5% of cases.

CONCLUSION

The nano-silver solution with a particle size of 1-2 nm proved its ability to penetrate the dentinal surfaces and create a final film covering the dentinal surface of the root canal before applying the sealer.

MTA Enhances the Potential of Adipose-Derived Mesenchymal Stem Cells for Dentin-Pulp Complex Regeneration

The aim of the current study was to investigate the effects of mineral trioxide aggregate (MTA) on the proliferation and differentiation of human adipose-derived mesenchymal stem cells (Ad-MSCs) as a surrogate cell source in futuristic stem-cell-based endodontic therapies. Human Ad-MSCs and mesenchymal stem cells derived from bone marrow (BM-MSCs) were isolated from liposuction waste adipose tissue and femur, respectively, and the effects of MTA-conditioned media on their viability, mineralization potential, and osteo/odontogenic differentiation capacity were subsequently evaluated. Alkaline phosphatase (ALP) activity, quantitative alizarin red S staining, and quantitative reverse transcription-polymerase chain reaction (qRT-PCR) analyses were performed to investigate and compare the osteo/odontogenic induction potential of MTA on the Ad/BM-MSCs. The results of cytotoxicity assay revealed that at different concentrations, MTA-conditioned medium was not only biocompatible toward both cell types, but also capable of promoting cell proliferation. ALP activity assay showed that 0.2 mg/mL was the optimal concentration of MTA-conditioned medium for osteo/odontogenic induction in Ad/BM-MSCs. The expression of osteo/odontogenic gene markers was increased in Ad/BM-MSCs treated with 0.2 mg/mL MTA-conditioned media. Our results indicated that MTA can efficiently enhance the osteo/odontogenic potential of Ad-MSCs, and thus they can be considered as a better cell source for dentin-pulp complex regeneration. However, further investigations are required to test these potentials in animal models.

Knowledge and Attitude towards Retrograde Peri-Implantitis among Italian Implantologists: A Cross-Sectional Survey

BACKGROUND

Retrograde peri-implantitis (RPI) is a pathological entity with an unclear etiology (e.g., overheating during implant insertion, residual infection of the tooth replaced by the implant or the endodontic lesion of neighboring teeth) and an extremely low prevalence and has been scarcely investigated. Therefore, the aim of this cross-sectional survey was to evaluate the knowledge and attitude of Italian implantologists regarding RPI.

METHODS

An anonymous questionnaire was sent via email to implantologists randomly selected, including a section about demographic information and questions related to RPI origin, radiographic representation, symptoms and treatment options. All questions were multiple answer and close-ended. Binomial logistic regression was performed to investigate the relationship between correct answers and the following independent variables: age, years of experience and number of dental implants placed per year.

RESULTS

In total, 475 implantologists completed the questionnaire, with a response rate of 46.3%. Based on the results of the study, incorrect answers were associated with less experienced participants (<80 implants/year) for all questions evaluated, with the exception of treatment strategies. Furthermore, 26.7% of the survey takers did not recognize radiographic representation of RPI and 35.5% picked "implant removal" when asked about treatment modality.

CONCLUSIONS

The majority of participants were able to recognize symptoms and indicated the probable causes of RPI; however, around 30% of them showed very limited knowledge of available management strategies.

Cytotoxicity of universal dental adhesive systems: Assessment in vitro assays on human gingival fibroblasts

Universal adhesives are the most important innovation in restorative dentistry. They are composed of different monomers, solvents and fillers. The potential cytotoxic effect of these materials is an important scientific aspect in recent literature. The aim of this study was to determine, using different in vitro techniques, the cytotoxicity evaluation of seven universal enamel-dental adhesives on human gingival fibroblasts. For this purpose, seven universal dental enamel adhesives have been evaluated by in vitro cytotoxicity tests using direct contact tests (an unpolymerized and a polymerized method) and an indirect contact test: preparation of extracts. The polymerized method showed a cytotoxicity range from 36% (G-PremioBond, GPB) to 79% (FuturaBond M+, FB). With the unpolymerized direct methods the range was from 4% (Prime&Bond Active, PBA) to 40% (Ibond Universal, IB) for undiluted adhesives; generally passing to the major dilutions the test showed a strong inhibitory activity by all the adhesives. Whereas with the indirect method by diluting the extracts of all dental adhesives the cell viability increased. The data obtained from the work has shown a lower cytotoxic effect of Optibond Solo Plus (OB) and Adhesive Universal (AU) with more reliable results with the extracts technique. The choice of reliable in vitro cytotoxic technique could represent, in dental practice, an important aid for clinical procedures in the use of adhesive systems.