ObjectivesThe aim of this cross-sectional study was to investigate an association between the prevalence of root-filled teeth (RFT) or apical periodontitis (AP) and some systemic conditions or smoking habits in an adult Portuguese population.MethodsMedical histories, including age, gender, presence of cardiovascular disease (CVD), diabetes mellitus (DM), allergies, smoking status, and endodontic treatment data of 421 patients (10,540 teeth) were recorded. The prevalence of root filled teeth and the periapical status were assessed through panoramic radiographies. Periapical status was classified according to the Periapical index and AP was defined as PAI-score ≥3. Statistic analysis was performed with PASW Statistics 20.0 using qui-square tests, odds-ratio and confidence intervals (95%).ResultsThe overall prevalence of AP and RFT was 2.2% and 4.2%, respectively. RFT increased the possibility of having AP (p<0.0001). Men's group showed a higher percentage of teeth with AP (p<0.0001), less RFT (p=0.05) and more residual roots (2.3%). Smoking increased the probability of having AP (p=0.002) and RFT (p=0.045). A positive correlation was observed between RFT and DM (p=0.040). No statistically significant difference was found between AP and CVD, DM or allergies neither between RTF and CVD or allergies.ConclusionsThe higher prevalence of AP and/or RFT in smoker subjects and in diabetic patients can suggest a relationship between oral and systemic health. More epidemiological studies are required before definitive conclusions can be made

Objectives: The significance of microorganisms in root canals with regard to the aetiology of periapical infection and the need for crucial bacteria control during treatment are undeniable. In this study, we re-port and discuss a review of the literature on Microbiological Root Canal Sampling (MRS). The procedure is analyzed in detail, discussing its powers, limitations and the influence of sample collection procedures on the incidence of true and false positive results. Data sources: MEDLINE/PUBMED, B-On and library files of Oporto University were accessed. Selection: Papers were selected using the keywords: “root ca¬nal sampling”; “apical periodontitis”; “endodontic pathogens”; “root canal infection”; “Culture”; “molecular biology”. The references were selected under inclusion criteria such as English language, accessibility, rel¬evance to the theme and scientific rigor. Conclusions: This review illustrated the absolute need to adhere to strict methodology procedures if valid samples are to be obtained. A combination of Culture and molecular identification approaches have confirmed the polymicrobial nature of endodontic infections with a pre¬dominance of anaerobic bacteria. Nucleic acid-based techniques provide significant additional information particularly regarding the not-yet-cultivable species of the microbial community, but greatly increase the budget of the procedure. Thus, assessment of the endodontic microflora, in the context of a polymicro¬bial biofilm ecosystem, and its relevance to endodontic treatments must rely in the complementariness of Culture and Metagenomics approaches as they are neither mutually exclusive nor competitive, but strongly complementary.

Methicillin-resistant Staphylococcus aureus (MRSA) is considered one of the most harmful bacteria to human health. Dentistry, like all healthcare disciplines, places great emphasis on preventing scenarios that may result in cross-infection. Although various tested and already used materials are suitable for filling the root canal system, Gutta-Percha (GP) remains the preferred and widely accepted gold standard. Objective: We performed an in vitro analysis of the contamination of GP points, regarding the strains of Methicillin-resistant (MRSA) and Methicillin-sensitive (MSSA) Staphylococcus aureus, using classical microbiology methods and molecular biology techniques. Methods: Gutta-Percha points of two different brands from opened packages (already in use for 1 month) were collected for analysis. The assessment involved incubating the GP points in Brain Heart Infusion (BHI) medium to detect microbial growth. Growing microorganisms were plated on a selective and differential chromogenic medium for MRSA/MSSA strains, and the identification of isolates was confirmed by Polymerase Chain Reaction (PCR). In the case of microbial growth, the GP point was submitted to a disinfection protocol. Results: From the 315 collected GP points, only 6 (1.9%) resulted in being positive for microbial growth. After confirmation by PCR, only one sample of the six GP points was contaminated by MRSA, and the remaining five were MSSA-contaminated. The disinfection protocol was effective in all contaminated GP points. Conclusions: The Gutta-Percha points from opened pre-sterilized packages showed a very low degree of contamination by MRSA/MSSA. However, the detection of MSSA and MRSA strains raises concerns about potential contamination in dental clinic environments, and this risk cannot be considered negligible.

Cone-beam computed tomography (CBCT) is widely utilized in endodontics for evaluating root canal shaping outcomes, offering critical three-dimensional imaging capabilities. This study aims to assess the differences in apical and root canal preparation across various instrumentation techniques using CBCT. A systematic search of the Medline database (via PubMed) and Web of Science was performed up to 12 April 2025, yielding a total of 70 studies, with 45 full-text articles assessed for eligibility; 28 were included in the review. Studies showed great heterogeneity in experimental design, anatomical variables, and outcome measurements. The results indicate that rotary instruments, such as ProTaper Next^® and XP-Endo Shaper^®, were reported more frequently or showed favorable shaping trends in individual studies. Although rotary systems often appeared advantageous, conclusions were limited by study design variability and a lack of correlation with clinical outcomes. The evidence highlights the need for standardized methodologies and further research, especially on manual techniques. CBCT remains a valuable research tool despite inherent spatial resolution limitations.

ObjectivesAssessment of bacterial reduction after chemo-mechanical preparation (using 3% sodium hypochlorite) with or without intracanal dressing (calcium hydroxide paste (Ca(OH)2) or 2% chlorhexidine digluconate gel (CHX)) in necrotic pulps associated or not with apical lesion.MethodsProspective clinical trial, in 69 adult patient's teeth with pulpal necrosis associated or not with apical periodontitis. Microbiological root-canal-sampling occurred before treatment (S1), after chemo-mechanical preparation (S2) and after 14 days intracanal dressing (S3). Colony Forming Units (CFU) were counted after growth in aerobic, anaerobic and microaerofilic cultures. Comparison of the median CFUs treatments and culture media was done with the Friedman test. Comparison of the intracanal dressing effect at S3 was done with the Wilcoxon and the Mann–Whitney tests. Because of the huge differences in bacterial counts variations were expressed as log10 to analyze differences among intracanal medication groups. S2 and S3 counts were expressed as percentage of CFU reduction regarding S1 counts.ResultsSignificant differences were detected between S1, S2 and S3 (Friedman test; p<0.001), showing a significant decrease from S1 to S2 (Wilcoxon test; p<0.004), followed by a significant increase from S2 to S3 (p<0.001) for the CHX group, maintenance for the Ca(OH)2 group in aerobic/anaerobic (Wilcoxon test; p=0.777/0.227), and increase in the microaerofilic culture (Wilcoxon test; p=0.047). The two groups only differed significantly in S3 (Mann–Whitney test; p≤0.001), with a worse performance in the CHX group.ConclusionsTreatment significantly reduced the number of bacteria but failed to render all root canals sterile. Ca(OH)2 performed better than CHX gel