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Aim: To investigate what happens to cross‐sectionally identified root‐filled teeth over a 6‐year period, regardless of the time that elapsed since primary root canal treatment, in a cohort of adult patients regularly attending a Public Dental Service. A secondary aim was to investigate how the cumulative events affecting root‐filled teeth over the same time were associated with variables obtained from a baseline examination. Methodology: Adult patients with ≥1 previously root‐filled tooth and regularly attending the Public Dental Service in Örebro County were enrolled for study participation in 2015. General dental practitioners examined all identified root‐filled teeth in this cohort at baseline using a standardized protocol and were also responsible for further decision‐making and treatments. After six years, information on events of the root‐filled teeth was collected from dental records. The highest rating (most invasive treatment) on a 5‐point ordinal scale was used in the analyses. Regression analyses with stepwise selection were performed for associations between patient‐ and tooth‐related factors and events. Results: A total of 445 patients with 1007 root‐filled teeth were followed the entire observation time. Twenty (2.0%) of the root‐filled teeth had endodontic retreatment and 150 (14.9%) were extracted over six years. Among teeth with periapical radiolucency or pain, the majority did not undergo retreatment or extraction; however, the multivariate analysis demonstrated that retreatment or extraction was associated with baseline recordings of teeth with periapical radiolucency (p <.0001), tenderness to percussion (p <.0001), and poor coronal restoration (p <.0001). Conclusions: This study corroborates the notion that in general dentistry, root‐filled teeth with radiological signs of apical disease often remain untreated over time. Furthermore, it also reveals that root‐filled teeth presenting with mild pain do not necessarily receive any intervention. However, teeth with baseline signs of apical periodontitis, pain, or inadequate coronal restoration were more likely to have received intervention during the six‐year period. [ABSTRACT FROM AUTHOR]

Aim: To explore associations between root filled teeth, primary and secondary apical periodontitis, and levels of inflammatory markers in blood from patients with a first myocardial infarction and matched controls. Methodology: Between May 2010 and February 2014, 805 patients with a first myocardial infarction and 805 controls, matched for sex, age, and postal code area, were recruited to the multicentre case–control study PAROKRANK (periodontitis and its relation to coronary artery disease). All participants underwent a physical and oral examination, as well as blood sampling. Using panoramic radiography, root filled teeth, primary apical periodontitis, and secondary apical periodontitis were assessed by three independent observers. Blood samples were analysed with enzyme‐linked immunosorbent assay method for the following inflammatory markers: interleukin‐1β (IL‐1β), IL‐2, IL‐6, IL‐8, IL‐12p70, tumour necrosis factor‐α, and high‐sensitivity C‐reactive protein (hsCRP). Additionally, white blood cell count and plasma‐fibrinogen were analysed. Associations between endodontic variables and the levels of inflammatory markers were statistically analysed with Mann–Whitney U‐test and Spearman correlation, adjusted for confounding effects of baseline factors (sex, age, myocardial infarction, current smoking, diabetes, family history of cardiovascular disease, education, marital status, and periodontal disease). Results: Mean age of the cohort was 62 years, and 81% were males. Root fillings were present in 8.4% of the 39 978 examined teeth and were associated with higher levels of hsCRP, fibrinogen, and leukocyte count, but lower levels of IL‐2 and IL‐12p70. After adjusting for confounders, root filled teeth remained associated with higher levels of fibrinogen, but lower levels of IL‐1β, IL‐2, IL‐6, and IL‐12p70. Primary apical periodontitis was found in 1.2% of non‐root filled teeth and associated with higher levels of IL‐8 (correlation 0.06, p =.025). Secondary apical periodontitis was found in 29.6% of root filled teeth but did not relate to the levels of any of the inflammatory markers. Conclusions: This study supports the notion that inflammation at the periapex is more than a local process and that systemic influences cannot be disregarded. Whether the observed alterations in plasma levels of inflammatory markers have any dismal effects on systemic health is presently unknown but, considering the present results, in demand of further investigation. [ABSTRACT FROM AUTHOR]

Aim: This historical prospective cohort study of the adult population of Sweden is based on data from a national registry: the primary aim was to evaluate the long‐term survival of teeth after periradicular surgery. A secondary aim was to identify factors predictive of extraction within 10 years of registration of periradicular surgery. Methodology: The cohort consisted of all individuals who had undergone periradicular surgery to treat apical periodontitis, as reported to the Swedish Social Insurance Agency (SSIA) in 2009. The cohort was followed until 31 December 2020. Subsequent registrations of extractions were collected for Kaplan–Meier survival analyses and survival tables. The patients' sex, age, dental service provider and tooth group were also retrieved from SSIA. Only one tooth per individual was included in the analyses. Multivariable regression analysis was used and p <.05 was considered statistically significant. The reporting guidelines STROBE and PROBE were followed. Results: After data cleaning, and exclusion of 157 teeth, 5622 teeth/individuals remained for analysis. The mean age of the individuals at the time of the periradicular surgery was 60.5 years (range 20–97, standard deviation 13.31); 55% were women. At the end of the follow‐up, that is, up to 12 years, a total of 34.1% of the teeth had been reported as extracted. The multivariate logistic regression analysis, based on follow‐up data at 10 years after registration of the periradicular surgery, included 5548 teeth, of which 1461 (26.3%) had been extracted. Significant associations between the independent variables tooth group and dental care setting (both p <.001) and the dependent variable extraction were found. The highest odds ratio (OR) for extraction applied to tooth group: compared to maxillary incisors and canines, mandibular molars were at greatest risk of extraction (OR 2.429, confidence interval 1.975–2.987, p <.001). Conclusions: After periradicular surgery in predominantly elderly people in Sweden, approximately three‐quarters of the teeth are retained over a 10‐year period. The type of tooth is associated with extraction: mandibular molars are at greater risk of extraction than maxillary incisors and canines. [ABSTRACT FROM AUTHOR]

To assess the efficiency of AI methods in finding radiographic features in Endodontic treatment considerations. This review was based on the PRISMA guidelines and QUADAS 2 tool. A systematic search was performed of the literature on cases with endodontic treatments, comparing AI algorithms (test) versus conventional image assessments (control) for finding radiographic features. The search was conducted in PubMed, Scopus, Google Scholar and the Cochrane library. Inclusion criteria were studies on the use of AI and machine learning in endodontic treatments using dental X-rays. The initial search retrieved 1131 papers, from which 24 were included. High heterogeneity of the materials left out a meta-analysis. The reported subcategories were periapical lesion, vertical root fractures, predicting root/canal morphology, locating minor apical foramen, tooth segmentation and endodontic retreatment prediction. Radiographic features assessed were mostly periapical lesions. The studies mostly considered the decision of 1–3 experts as the reference for training their models. Almost half of the included materials campared their trained neural network model with other methods. More than 58% of studies had some level of bias. AI-based models have shown effectiveness in finding radiographic features in different endodontic treatments. While the reported accuracy measurements seem promising, the papers mostly were biased methodologically. [ABSTRACT FROM AUTHOR]

Objectives: To examine the dimensional changes of endodontic sealers during 18 months using three‐dimensional (3D) surface scanning and subtraction radiography in a novel in vitro sealer‐extrusion model. Material and Methods: Fifty endodontically instrumented acrylic teeth were randomly allocated to five groups (n = 10) filled with Apexit Plus, AH Plus, BioRoot RCS, TubliSeal EWT, and gutta‐percha (control). Freshly mixed sealers were intentionally extruded during obturation. All teeth were immersed in a physiologic solution for up to 18 months. Blinded 3D surface scans (resolution: ~10 μm) and digital radiographs of the teeth were obtained at baseline (immediately after obturation); and then after 1 week, and at 1, 3, and 18 months. For blinded assessment of sealer dimensional change, 3D models and radiographs were superimposed using specific software. Volumetric differences, root mean square (RMS), and area change from subtraction radiography measured at each period within each sealer group were thereafter calculated. Repeated measures analyses were done with Bonferroni adjustment for multiple comparisons; standard errors, p values, and 95% confidence intervals (CI) were reported. Results: Analyses of the volumetric data confirmed significant, progressive material loss for Apexit Plus when compared to the other investigated sealers or the control group (p ≤ 0.02). Immersion period significantly influenced the volumetric dimensional changes of Apexit Plus already after 1 month (p < 0.01). For TubliSeal EW, the effect of the immersion period on the dimensional changes was noted after immersion for 3 months (p ≤ 0.02), while for BioRoot RCS this was evident only at 18 months (p < 0.01). Same trends were noted for the RMS data, whereas progressive dimensional changes using subtraction radiography only revealed significant changes for Apexit Plus (p = 0.01). Conclusions: The largest dimensional changes were shown by Apexit Plus, followed by Tubliseal EWT and BioRoot RCS. AH Plus remained stable throughout 18 months. [ABSTRACT FROM AUTHOR]

Aims: (a) The aim of this study was to investigate both the formation of dense connective tissue within the dental pulp, and its association with pulpal inflammation in teeth with advanced carious lesions; and (b) to investigate in vitro whether inflammation affects the expression of markers related to chondrogenesis/osteogenesis in pulp cells. Materials and methods: Radiology and Histology: Forty‐six teeth with advanced carious lesions were radiographically investigated for intra‐pulpal radiodense structures. Specimens were processed for histology and stained with haematoxylin/eosin and proteoglycan‐specific stains. The intra‐pulpal connective tissue was scored as pulp stones or ectopic connective tissue. Cell culture: pulpal cells from human third molars (n = 5) were cultured in chondrogenic medium +/− TLR2/4 agonists. Expression of the genes IL6, TLR2/4, SOX9, COL1A1, COL2A1, TGFB1, RUNX2 and ALPL was assessed by qPCR. Proteoglycan content within cultures was assessed spectrophotometrically. Results: Radiodense structures were discovered in about half of all pulps. They were associated with ectopic connective tissue (χ2 = 8.932, p =.004, OR = 6.80, 95% CI: [1.84, 25.19]) and with pulp stones (χ2 = 12.274, df = 1, p <.001, OR = 22.167, 95% CI: [2.57, 200.00]). The morphology of the ectopic tissue resembled cartilage and was associated with inflammatory infiltration of the pulp (χ2 = 10.148, p =.002, OR = 17.77, 95% CI: [2.05, 154.21]). After continuous stimulation of cultured cells with TLR2/4 agonists, the expression of two inflammatory markers increased: IL6 at Days 7 (p =.020) and 14 (p =.008); TLR2 at Days 7 (p =.023) and 14 (p =.009). Similarly, expression of chondrogenic markers decreased: SOX9 at Day 14 (p =.035) and TGFB1 at Day 7 (p =.004), and the osteogenic marker COL1A1 at Day 7 (p =.007). Proteoglycan content did not differ between unstimulated and stimulated cells. Conclusions: Ectopic connective tissue resembling cartilage can form in teeth affected by advanced carious lesions. This tissue type is radiographically visible and is associated with inflammatory infiltration of the pulp. Although TLR2/4 agonists led to an inflammatory response in cell culture of pulp cells, the effect on the expression of osteogenic/chondrogenic markers was limited, suggesting that immune cells are needed for connective tissue formation in vivo. [ABSTRACT FROM AUTHOR]

Background: Guided Endodontics is suggested as a reliable method for management of teeth with pulp canal obliteration (PCO). The guide used for this usually involves multiple teeth to gain stability but is bulky. It is therefore suboptimal to be used along with rubber dam.Aim: To describe the use of a minimized single-tooth guide template in three patients with radiographic evidence of PCO.Design: The template was designed and fabricated using the cone-beam computed tomography (CBCT) scan and a surface scan image of the involved teeth. In all three patients, the root canals were successfully negotiated within 15 minutes, with the template involving only the tooth in focus or with neighboring half of the teeth. The operator stabilized the template if required.Conclusions: This case series shows clinically that successful outcome can be obtained during guided endodontics with the use of a single-tooth template in previously traumatized anterior teeth with PCO. [ABSTRACT FROM AUTHOR]

The infectious disease denial caries results in lesions that may affect enamel, dentin, pulp, and cementum. If a caries lesion has progressed to the stage at which it requires restorative intervention, it is important that the clinician understand the tissue changes in the dentin that are likely to have taken place during lesion development. Until the present, no major distinction between the restorative treatment of active (rapidly progressing) and arrested (slowly progressing) lesions has been made, despite the fact that the two conditions exhibit major differences in tissue changes in the pulp-dentin complex. Intratubular changes and tertiary dentin formation will affect the outcome of the restorative treatment. In unaffected dentin and in rapidly progressing lesions, permeable tubules persist, and when the preparation of carious teeth results in the opening of unaffected dentin, greater care must be taken in all phases of the restorative procedures than if the dentin is impermeable. An active, deep lesion can be changed to an arrested lesion by a two-step excavation approach. Optimal assessment of the prevailing clinical conclusions can only be made on the basis of thorough knowledge of the biology of the pulp-dentin organ. (Quintessence Int 2001.'32. 717-736) [ABSTRACT FROM AUTHOR]

The aim of this case report was to show the concept of guided endodontics in a maxillary first molar with limited interocclusal space. Guided endodontics involves merging cone-beam computed tomographic imaging and a surface scan of the tooth in order to create a guide to perform a drill path into the seemingly obliterated root canal. In the molar region, the interocclusal space is often too small to accommodate the guide, bur, and handpiece at once, and, therefore, a modified approach is presented. A 52-year-old man was referred because the dentist had failed to localize the distobuccal root canal of a maxillary molar (#3) associated with apical pathosis. After reopening and rubber dam placement, a glide path was established for both the palatal first mesiobuccal root canal and the second mesiobuccal using a size 10 hand file and coronal flaring. Further instrumentation to the working length was achieved by reciprocating file size 25. All 3 canals were temporarily filled with calcium hydroxide. For the distobuccal root canal, guided endodontics was chosen in order to avoid further impairment of the tooth because negotiation of the canal failed even with the use of the operating microscope. Following the merged data obtained from the cone-beam computed tomographic and surface scans, a translucent SICAT Optiguide (SICAT, Bonn, Germany) was constructed containing a sleeve representing the proper direction of a drill path in order to reach the distobuccal root canal. The access cavity was temporarily filled with a composite material made for light-curing. Before light curing, the Optiguide was replaced on the teeth, and a steel pin was pressed through the sleeve and the composite whereby the proper drill path direction was transferred into the composite. After polymerization and removal of the Optiguide and pin from the composite base sleeve, the guided drilling could be performed. This case report is the first on guided access preparation in a molar with pulp canal obliteration and limited interocclusal space. The demand for more interocclusal space was solved by transforming the virtual drill path into a composite-based intracoronal guide. The use of digital technology was essential. [ABSTRACT FROM AUTHOR]

Objective: To systematically review the quality of evidence of available in vitro solubility studies on endodontic sealers according to prespecified evidence criteria.Material and Methods: This systematic review was based on the PRISMA guidelines and the AMSTAR measurement tool. A systematic duplicate search of the literature on endodontic sealer solubility studies was conducted in PubMed and Embase databases (until 18 October 2017). Mapping terms to subject headings and free text terms were used and combined with hand searching before exclusion of duplicates. Studies specifically dealing with endodontic sealer solubility were selected. The evidence level was graded (low, medium or high) independently by two investigators following systematic data extraction in pilot forms, which was based on prespecified evidence criteria and the modified CONSORT checklist for in vitro studies on dental materials.Results: The search retrieved 1053 articles, from which 88 were assessed in full. From the 63 articles retained in the final analysis, 11 were classified as having moderate and 52 as low quality of evidence (0 high). The studies graded as low had low sample size (n < 10) and/or insufficient details to allow replicability. Most of the studies did not conform to the modified CONSORT checklist and did not include parameters considered relevant in the prespecified criteria.Conclusions: Existing in vitro studies on the solubility of endodontic sealers do not demonstrate a high quality of evidence. Most of these studies do not present systematic reporting nor employ relevant parameters prespecified in our evidence criteria. [ABSTRACT FROM AUTHOR]

Summary: Background: After root canal treatment, a choice is made between different coronal restorations which in the long run could affect the survival of the tooth. Objective: To compare demographic characteristics between individuals choosing an indirect coronal restoration (crown, inlay/onlay) and individuals choosing other restorations after completion of a root filling. Methods: The cohort consisted of all root‐filled upper first molars that were reported to the tax‐funded Swedish Social Insurance Agency (SSIA) during 2009. After registration of the root filling, any subsequent coronal restorations within 2 years were identified. The crown group consisted of individuals registered with an indirect coronal restoration and the restoration group was the remaining individuals with a direct coronal restoration or lacking registration. Demographic data (gender, disposable income, age, educational level, civil status and country of birth) were received from Statistics Sweden or the SSIA. Statistical analyses included chi‐square test, t test and logistic regression analysis. P < 0.05 was considered statistically significant. Results: An indirect coronal restoration was received by 7806 individuals (21.9%), and 27 886 individuals (78.1%) received a direct restoration. All demographic variables except gender differed significantly between groups. Logistic regression analysis found significant associations for all demographic variables and the registration of an indirect restoration except for country of birth and gender. Conclusions: The identified demographic differences between individuals choosing to restore their newly root‐filled teeth with an indirect restoration compared to those receiving other restorations may indicate that the tax‐funded Swedish dental insurance fails to provide dental care on equal terms for Swedish citizens. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to re-assess the adoption of certain endodontic technology and central treatment principles of root canal treatments as advocated by guidelines presented by the European Society of Endodontology.Material and Methods: The questionnaire included the same questions in 2003 and 2013. The general dental practitioners (GDPs) anonymously reported how frequent ('often', 'occasionally', and 'never') they used certain endodontic technology and adhered to central treatment principles. The statistical analyses were performed using Chi-squared test and Goodman-Kruskal's γ-coefficient as an association measure.Results: The overall response rate of the 2013 group was 46.5% (n = 531). The frequencies of GDPs reporting often use of rubber dam, apex locator and rotary NiTi instruments were significantly higher (p < .0001) than in 2003, as well as reporting the use of composite resin for coronal sealing (p < .019). Adoption was significantly influenced by the factors gender (p = .601) and time since graduation (p = .361), and the cluster analyses revealed the neglected use of rubber dam to be associated with no established postoperative recall system.Conclusions: After 10 years, there was a higher frequency of GDPs who had adopted certain endodontic technologies. However, progress towards high-quality root canal treatment might be obstructed as the majority of GDPs avoids consistent use of rubber dam, and routinely neglects recalls for postoperative controls of their endodontic treatments. [ABSTRACT FROM AUTHOR]

The objective of this study was to test the inactivation efficiency of two different light-based treatments, namely ultraviolet B (UVB) and ultraviolet C (UVC) irradiation, on Pseudomonas aeruginosa biofilms at different growth stages (24, 48 and 72 h grown). In our experiments, a type of AlGaN light-emitting diodes (LEDs) was used to deliver UV irradiation on the biofilms. The effectiveness of the UVB at 296 nm and UVC at 266 nm irradiations was quantified by counting colony-forming units. The survival of less mature biofilms (24 h grown) was studied as a function of UV-radiant exposure. All treatments were performed on three different biological replicates to test reproducibility. It was shown that UVB irradiation was significantly more effective than UVC irradiation in inactivating P. aeruginosa biofilms. UVC irradiation induced insignificant inactivation on mature biofilms. The fact that the UVB at 296 nm exists in daylight and has such disinfection ability on biofilms provides perspectives for the treatment of infectious diseases. [ABSTRACT FROM AUTHOR]

The caries process in dentin involves the degradation of both mineral and organic matrix. The demineralization has been demonstrated to be caused by bacterial acids. However, the collagen degradation is considered to be initiated by endogenous proteolytic enzymes, mainly collagenolytic matrix metalloproteinases (MMPs). This paper aims to relate salivary MMP-8 (or salivary collagenase-2) and tissue inhibitor of MMP (TIMP-1) levels to manifest caries in a large number of subjects. A random sample of 451 adults (aged 18-87 years) living in the south of Sweden was included in this study. Standard clinical examinations were performed, and stimulated saliva was collected and analyzed for concentrations of MMP-8, TIMP-1 and total protein, using an immunofluorometric assay, an enzyme-linked immunosorbent assay and the Bradford assay, respectively. Salivary numbers of mutans streptococci and lactobacilli were determined using a chair-side kit. Subjects with manifest caries lesions presented with elevated levels of MMP-8 (p < 0.001) as well as total protein, MMP-8/TIMP-1 ratio, bleeding on probing and plaque index (p = 0.05) compared with subjects without manifest caries. Multiple linear regression analysis with caries as the dependent variable revealed MMP-8 as the only significant explanatory variable (p < 0.001). TIMP-1 was not significant in any case. Using MMP-8 as the dependent variable revealed total protein concentration, caries lesions (p ≤ 0.001) and salivary secretion rate (p = 0.05) as explanatory variables. In conclusion, our data reveal that subjects with manifest caries lesions have elevated levels of salivary MMP-8 relative to subjects with no caries lesions. [ABSTRACT FROM AUTHOR]

Purpose. The purpose was to study the reduction of intra-canal microflora in premolars with apical periodontitis instrumented with either apical box or apical cone preparation and to provide measurements of intervention effects to allow proper power calculation in future clinical trials. Methods. Twenty-four patients were centrally randomized to apical box preparation (size #60) or cone preparation (apical size #25). The groups were comparable regarding the presence of primary caries and type of coronal restoration. In the course of canal preparation each tooth was irrigated with 2.5% NaOCl (12 ml). Lastly, the canals were filled with 17% EDTA (2 × 30 s) and 5% iodine potassium iodide (IKI) for 10 min. The canals were sampled for micro-organisms on four occasions: before instrumentation, after instrumentation, after application of IKI dressing and at the beginning of the second appointment 1 week later. Between the treatment sessions, the root canals were sealed with IRM cement. In the laboratory, culture techniques were used to measure microbial growth, which was classified as: none, very sparse, sparse, moderate, heavy or very heavy. Results. Initially, microbes were recovered in 88% of the teeth. Growth was classified as none in 35% of the teeth after instrumentation and in 50% after the application of IKI. Irrespective of the time of sampling, no significant difference in microbial growth reduction was observed between the two types of apical preparation. Based on the 1-week post-sampling, a power calculation revealed that over 900 patients are needed to show a difference of 9% between the two protocols tested. Conclusions. Future trials should be conducted using stringent protocols and as multi-centre trials for reaching the required information size. [ABSTRACT FROM AUTHOR]

Aim. The purpose of this study was to investigate the scanning and segmentation precision of surface models of molars for the detection of small volumes, such as the reduced pulp cavity; formation of mineral deposits; detection of narrow root canals and to improve the clinical and morphological understanding of the number of root canals and their configuration. Methods. Eighteen human molars were scanned using X-ray micro-computed tomography. The reconstruction of the surface models had a precision of <1 voxel, using three-dimensional software and quantitative color mapping. In order to relate the measurements to changes over time the size of the pulp chambers was classified in two well-defined groups. Results. The mineral deposits were more evenly distributed in small pulp chambers than in large, but complete root canal calcification was never observed. No difference was observed in the material with respect to the presence of intra-radicular connections. In upper molars, a second mesiobuccal canal (mb2) frequency of 91% was found. The difference in length between the first mesiobuccal canal (mb1) and mb2 was <1 mm. The number of root canals could be related to the number of root cones. Conclusion. In summary, three-dimensional surface models were made with a high precision; an increased accumulation of mineral deposits was noted in molars with small pulp chambers and combined with the consistent pattern of intra-radicular connections, the potential endodontic treatment complexity is underlined in such cases. Finally, an improved understanding of root canal prevalence was reached, when merging well-defined definitions on root morphology and clinical classification systems. [ABSTRACT FROM AUTHOR]

There is a gap between the endodontic outcome that can be achieved and the outcome observed on the basis of worldwide general dental practitioner data. The quality of root canal treatment (RCT) is shaped by the dentist's knowledge, attitude, and skills, but it may also be influenced by the patient's demands and degree of satisfaction. The topic has only been sparsely investigated. Although dental health has increased over the years in Denmark, the number of performed root fillings has also increased, probably because the number of tooth extractions have declined and more molar teeth have been treated. Caries appears to be the main cause for performing RCT and a preventive approach by employing stepwise excavation may reduce RCT, but this strategy does not remove the gap. Factors influencing RCT quality could be the status on adoption of nickel-titanium rotary technology, more focus on infection control (rubber dam use, knowledge of factors important for prognosis), as dentists often think that they are good at doing RCT, but often perform inadequately, an alteration of clinician's awareness of their performance in the context of dental practices, seems warranted. Finally, the development of new preventive modalities for pulp and apical inflammation are crucial. [ABSTRACT FROM AUTHOR]

This study reports results from a practice-based study in which deep carious lesions were treated by general dental practitioners using stepwise excavation. The material comprised 94 teeth with deep carious lesions which the clinicians considered would result in pulp perforation if treated by a single and terminal excavation. At the first visit excavation of the peripheral dentine was completed. The outermost part of the central and necrotic dentine was gently removed with a sharp excavator. Standardized assessments of the dentine colour and consistency were made before application of a calcium hydroxide-containing base material and temporary filling. The final excavation was completed after a treatment interval ranging from 2 to 19 months, with a median of 6 months. Reassessments of the dentine colour and consistency were made before complete removal of demineralized dentine. The central dentine was significantly browner and less softened after the sealing period. After removal of the dark-brownish dentine during the final excavation, the colour and consistency of the exposed central dentine was found to resemble that of the completely excavated peripheral dentine. Only five cases resulted in pulp perforation during the final excavation. The high success rate of teeth surviving the final treatment without pulp exposure after 1 year of observation shows that it was possible for dentists in general practice to administer and manage the treatment of deep carious lesions, a process which may prolong tooth survival compared with conventional endodontic techniques. [ABSTRACT FROM AUTHOR]

The present study examines the correlation between caries lesions in enamel and the corresponding dentin reactions in proximal tooth surfaces with lesions ranging from enamel lesions to cavitations without dentin exposure. Using quantitative inhibition technique, the highest degree of tissue porosity, irrespective of lesion activity, was always noted along a Central-Traverse (CT), which followed the direction of the rods from the deepest point of penetration to the surface. The conical shape of approximal enamel lesions can thus be seen as the result of systematic variations in porosity along the rods determined by the specific interproximal environment. The initial dentin reaction, related to the enamel lesion approaching the enamel-dentin junction (EDJ), was seen as a local dentin translucency where the CT crossed the EDJ. Results from histomorphometric analyses revealed that, when the enamel lesions reached the EDJ, brownish discoloration in the dentin never exceeded the histologic contact area between the enamel lesion and the EDJ. In relation to the less advanced parts of the individual enamel lesion, the dentin responded with formation of translucent dentin. These reactions did not occur beyond an area determined by lines in the direction of the rods from the peripheral part of the enamel lesion towards the EDJ. The results did not support the view that dentin caries spreads along the enamel-dentin junction. The peripheral dentin translucency is therefore generated by stimuli transmitted along the rods of the less advanced parts of the enamel lesions.

Article Title and Bibliographic Information: Ways of enhancing pulp preservation by stepwise excavation—a systematic review. Hayashi M, Fujitani M, Yamaki C, Momoi Y. J Dent 2011;39(2):95-107. Epub 2010 Dec 3. Reviewer: Lars Bjørndal, DDS, PhD, Dr Odont Purpose/Question: To determine the clinical effectiveness of stepwise excavation for pulp preservation Source of Funding: Japanese Society of Conservative Dentistry Type of Study/Design: Systematic review Level of Evience: Level 2: Limited-quality patient-oriented evidence Strength of Recommendation Grade: Grade B: Limited-quality patient-oriented evidence [Copyright &y& Elsevier]

Bacterial biofilm infections often involve aggregates of bacteria heterogeneously distributed throughout a tissue or on a surface (such as an implanted medical device). Identification of a biofilm infection requires direct visualization via microscopy, followed by characterization of the microbial community by culturing or sequencing-based approaches. A sample, therefore, must be divided prior to analysis, often leading to inconsistent results. We demonstrate a combined approach, using scanning electron microscopy and next-generation shotgun sequencing, to visually identify a biofilm and characterize the microbial community, without dividing the sample. A clinical sample recovered from a patient following a dental root-filling procedure was prepared and visualized by scanning electron microscopy. DNA was then extracted from the sample several years later and analyzed by shotgun sequencing. The method was subsequently validated on in vitro cultures of Pseudomonas aeruginosa biofilm. Between 19 and 21 different genera and species were identified in the clinical sample with an estimated relative abundance greater than 1% by two different estimation approaches. Only eight genera identified were not associated with endodontic infections. This provides a proof-of-concept for a dual, microscopy and sequencing-based approach to identify and characterize bacterial biofilms, which could also easily be implemented in other scientific fields. [ABSTRACT FROM AUTHOR]