Changes in the Difficulty of Endodontic Cases Treated by Undergraduate Students at a University Clinic Between 1971 and 2019.

Objective: This study aimed to assess the proportions of complicated endodontic cases treated by undergraduate dental students in a University clinic now and in the past.

Material And Methods: Data were obtained from the electronic records and previous publications from the Faculty of Dentistry, University of Oslo, Norway. The operators were dental undergraduate students in their final 2 years of training.

Root-filling materials for endodontic surgery: biological and clinical aspects.

The placement of root filling materials aims to prevent the occurrence of post-treatment apical periodontitis following completion of endodontic treatment. Materials should possess properties that will not permit bacterial invasion and infection, namely excellent sealing ability and/or antibacterial properties. In root-end filling procedures or repair of root perforations, the root filling materials are placed in a particularly challenging clinical environment, as they interface with a relatively large area with the periradicular tissues.

Radiographic outcome of endodontic treatment and retreatment of teeth with apical periodontitis using two different root canal irrigants. A prospective cohort study.

Aim: The aim of this prospective cohort study was to compare the radiographic outcome of endodontic treatment and retreatment of teeth with apical periodontitis using either 1% sodium hypochlorite (NaOCl) or 2% chlorhexidine digluconate (CHX) for root canal irrigation.

Materials And Methods: In the years from 2013 to 2015 standard irrigation varied by semester between NaOCl and CHX at the Department of Endodontics at the Faculty of Dentistry. During that time, 912 teeth received treatment for apical periodontitis in 744 patients, of whom 532 responded to the request for a 1-year follow-up.

Endodontic sealers after exposure to chlorhexidine digluconate: An assessment of physicochemical properties.

Objectives: Final root canal irrigation should ideally maintain the physicochemical stability of root canal sealers. We seek to assess the effect of contact with 2% chlorhexidine digluconate (CHX) on the physicochemical properties of AH Plus, BioRoot™ RCS, and Pulp Canal Sealer (PCS).

Methods: Mixed sealers were placed in cylindrical teflon molds and allowed to set for 1.

Antibacterial Activity of Root Repair Cements in Contact with Dentin-An Ex Vivo Study.

This study assessed the antibacterial characteristics of the dentin/material interface and dentin surfaces exposed to experimental hydraulic calcium silicate cement (HCSC) with or without bioactive glass (BG) replacement (20% or 40%) or mixed with a silver nanoparticle (SNP) solution (1 or 2 mg/mL), and Biodentine, TotalFill BC RRM putty and Intermediate Restorative Material (IRM). Human root dentin segments with test materials were assessed at 1 or 28 days. In one series, the specimens were split to expose the dentin and material surfaces.

Effect of exposure conditions on chemical properties of materials for surgical endodontic procedures.

This study investigated the role of aging and changes in environmental conditions on selected properties of a prototype radiopacified calcium silicate-based cement (TZ-base) with or without incorporation of silver nanoparticles or bioactive glass, and two commercial materials, Biodentine and intermediate restorative material. Materials were immersed in ultrapure water or fetal bovine serum for 28 days and were characterized with scanning electron microscopy and energy dispersive x-ray analysis. Immersion media were either replaced weekly or not replenished at all and were assessed for alkalinity and calcium release after 1, 7, 14, 21, and 28 days; antibacterial effect against 2-day monospecies biofilms; and cytotoxicity by the 3-(4,5 dimethylthiazolyl-2-yl)-2,5-diphenyl tetrazolium bromide assay after 1, 7, or 28 days.

Treatment outcome of surgical and non-surgical endodontic retreatment of teeth with apical periodontitis.

Aims: To evaluate and compare the treatment outcome of root filled teeth with apical periodontitis treated either non-surgically or by endodontic microsurgery, and to assess the influence of an intra-radicular post, clinical and demographic factors.

Methodology: Clinical and radiological data from 1157 patients with apical periodontitis in previously root filled teeth treated by postgraduate students at the Department of Endodontics, University of Oslo, between September 2010 and January 2020 with recall data at least 11 months from completion were studied. Surgical cases were scored using the Rud/Molven criteria and grouped into success, uncertain or failure at control.

Periapical and endodontic status among 65-year-old Oslo-citizens.

Aim: This cross-sectional study aimed to investigate the prevalence of apical periodontitis (AP) and root-filled teeth in a 65-year-old population in Oslo, Norway, and to investigate associations of pathosis and endodontic treatment with selected individual risk indicators and technical quality of root fillings.

Material And Methods: A random sample of 450 65-year-olds in Oslo answered a questionnaire and underwent a clinical and radiological examination (52% men and 48% women). Periapical radiographs were taken of all root-filled teeth and of teeth with apical radiolucency, and periapical status was evaluated using the Periapical Index.

Surface characteristics and bacterial adhesion of endodontic cements.

Objectives: To investigate the effect of inclusion of silver nano-particles (SNP) or bioactive glass (BG) on the surface characteristics and bacterial adhesion of prototype tricalcium silicate (TCS)-based cements alongside two commercial cements, under different aging periods and exposure conditions.

Materials And Methods: A basic formulation of radio-opacified TCS without (TZ-base) and with additions of SNP (0.5, 1, or 2 mg/ml) or BG (10 or 20%) was used.

Effect of chlorhexidine digluconate on antimicrobial activity, cell viability and physicochemical properties of three endodontic sealers.

Objective: Assess the biological and physicochemical properties of AH Plus, BioRoot RCS and Pulp Canal Sealer (PCS) leachates with and without chlorhexidine (CHX).

Methods: The sealers were studied in no contact and 1-minute contact with CHX. For biological properties (antibacterial activity and cytotoxicity), leachates were formed in saline of freshly mixed, 1-, 7- and 28 days set sealers.

Periapical status transitions in teeth with posts versus without posts: a retrospective longitudinal radiographic study.

Objectives: The aim of this study was to compare periapical status transitions in teeth after post placement compared with other post-endodontic treatments in root-filled teeth.

Material And Methods: This retrospective longitudinal radiographic study included radiographs of 284 patients with root filled and restored teeth with composite fillings (Endo-fill group,  = 100), crown or fixed prosthesis (Endo-crown group,  = 82) or post and core restorations (Endo-post group,  = 102). All post and core restorations were made of gold alloy.

The dentine-sealer interface: Modulation of antimicrobial effects by irrigation.

Aim: Assess whether sodium hypochlorite (NaOCl) or chlorhexidine (CHX) and two irrigation protocols may alter the antibacterial properties of dentine and three endodontic sealers using a novel ex vivo tooth model.

Methodology: Prior to antibacterial testing, the tooth model was validated by means of scanning electron microscopy (SEM) to evaluate the separation between dentine and sealer surfaces. Root blocks prepared from extracted human roots were pre-treated with 17% EDTA + 0.

Effects of an individualized training course on technical quality and periapical status of teeth treated endodontically by dentists in the Public Dental Service in Norway: An observational intervention study.

Aim: To investigate the effect of a continuing education course on technical quality and treatment outcome for root filled permanent teeth in Møre and Romsdal County, Norway.

Methodology: Fifty-two dentists employed in the Public Dental Service in Møre and Romsdal county, Norway, completed a two-day continuing education course in root canal treatment. Periapical radiographs of root filled teeth treated before and after the course, with at least one-year follow-up were identified and scored for technical quality and periapical status.

Effects of an individualised training course in endodontics on the knowledge and insights of dentists in Public Dental Service in Norway.

Objective: To evaluate the knowledge and insights of general dental practitioners regarding endodontic diagnosis and treatment principles before and after attending a 2-days continuing education course.

Materials And Methods: Sixty-seven dentists employed in the Public Dental Service in Møre and Romsdal county, Norway, were invited to a continuing education course in endodontics. Before and after the course, they answered a questionnaire weighing the importance of factors influencing the prognosis of endodontic treatment.

Antimicrobial and physicochemical characterization of endodontic sealers after exposure to chlorhexidine digluconate.

Objectives: Assess the antibacterial, physical and chemical properties of AH Plus, BioRoot RCS and Pulp Canal Sealer (PCS) in contact with 2% chlorhexidine digluconate (CHX) used as final irrigant prior to root canal obturation.

Methods: The antimicrobial properties were investigated by direct contact tests for planktonic and biofilm growth of E. faecalis, S.

Outcome of Endodontic Retreatment Using 2 Root Canal Irrigants and Influence of Infection on Healing as Determined by a Molecular Method: A Randomized Clinical Trial.

Introduction: This study compared the clinical and radiographic outcome of endodontic retreatment of teeth with apical periodontitis using either 1% sodium hypochlorite (NaOCl) or 2% chlorhexidine digluconate (CHX) as the irrigant. The influence of residual infection detected by a molecular method on the outcome was also examined.

Methods: Fifty-two root-filled teeth with apical periodontitis were randomly assigned into 2 groups according to the irrigant used during retreatment.

Maintenance of the aseptic working field during endodontic treatment.

The aim of this clinical quality study was to determine whether the aseptic working field is maintained during the endodontic procedure. Bacterial samples were collected from the rubber dam of 27 patients during endodontic treatment performed by postgraduate students at the Department of Endodontics, University of Oslo. A bacterial sample was first obtained immediately after disinfection of the working field (A), and the second sample was collected just before obturation or dressing with calcium hydroxide cement (B).

Microbial Analysis of Endodontic Infections in Root-filled Teeth with Apical Periodontitis before and after Irrigation Using Pyrosequencing.

Introduction: The root canal microbiota in root-filled teeth with post-treatment apical periodontitis before and after chemomechanical instrumentation and irrigation with either 1% sodium hypochlorite (NaOCl) or 2% chlorhexidine digluconate were analyzed by using the pyrosequencing method.

Methods: Samples from 10 root-filled teeth with apical periodontitis undergoing retreatment were taken before (S1) and after (S2) preparation using irrigation with either NaOCl (n = 5) or 2% chlorhexidine digluconate (n = 5). DNA was extracted, and the 16S rRNA gene (V3-V5) variable regions were amplified and subjected to pyrosequencing (GS junior 454) to determine the bacterial composition.

Antibacterial Activity of Endodontic Sealers against Planktonic Bacteria and Bacteria in Biofilms.

Introduction: The aim of this study was to investigate the antibacterial activity of 4 endodontic sealers against bacteria planktonic grown or in biofilms commonly detected from persistent and secondary endodontic infections.

Methods: The antibacterial activity of the sealers AH Plus, TotalFill BC sealer, RoekoSeal, and Guttaflow 2 was investigated for planktonic grown and 24-hour-old biofilms of Enterococcus faecalis, Staphylococcus epidermidis, Staphylococcus aureus, and Streptococcus mutans.

Results: AH Plus had high antibacterial activity toward all species investigated, both planktonic and in biofilms.

Influence of the Apical Preparation Size and the Irrigant Type on Bacterial Reduction in Root Canal-treated Teeth with Apical Periodontitis.

Introduction: This clinical study evaluated the influence of the apical preparation size using nickel-titanium rotary instrumentation and the effect of a disinfectant on bacterial reduction in root canal-treated teeth with apical periodontitis.

Methods: Forty-three teeth with posttreatment apical periodontitis were selected for retreatment. Teeth were randomly divided into 2 groups according to the irrigant used (2.

Antibacterial Effectiveness of 2 Root Canal Irrigants in Root-filled Teeth with Infection: A Randomized Clinical Trial.

Introduction: This study compared the antibacterial effects of 1% sodium hypochlorite (NaOCl) and 2% chlorhexidine digluconate (CHX) during retreatment of teeth with apical periodontitis.

Methods: Root canal-treated teeth with apical periodontitis were randomly distributed into 2 groups. Bacteriological samples were taken from the canals before (S1) and after (S2) preparation using either NaOCl or CHX irrigation and after calcium hydroxide medication (S3); 16S ribosomal RNA gene-based real-time quantitative polymerase chain reaction was performed to quantify total bacteria, streptococci, and Enterococcus faecalis.

Antibacterial activity of various root canal sealers and root-end filling materials in dentin blocks infected ex vivo with Enterococcus faecalis.

Objective: The aim was to investigate the antibacterial activity of the root-end filling materials MTA and IRM, different endodontic sealers and calcium hydroxide [Ca(OH)₂] in experimentally infected dentinal tubules.

Materials And Methods: Ninety-four human root segments were prepared and the root canals were enlarged to ISO size 90. After smear removal, the specimens were infected with Enterococcus faecalis for 3 weeks.

Periapical status of root-filled teeth in Norwegian children and adolescents.

Objective: To study the periapical status of root-filled permanent teeth of 9-17-year-olds in Møre & Romsdal county, Norway.

Materials And Methods: All permanent teeth with endodontic treatment in patients born in 1994-2001 were identified in the dental records of the Public Dental Service. The data collected consisted of chart entries and radiographs.

Detection of leachables and cytotoxicity after exposure to methacrylate- and epoxy-based root canal sealers in vitro.

Root canal sealing materials may have toxic potential in vitro depending on the cell line, cytotoxicity assay, material chemistry, and degree of polymer curing. The aims of the present study were to detect leaching components from epoxy- or methacrylate-based root canal sealers and to investigate the degree of cytotoxicity after exposure to extracts from these materials. Qualitative determination of substances released from the materials was performed by gas- and liquid chromatography/mass spectrometry.