1,039 research outputs found
3D micro-CT analysis of the interface voids associated with Thermafil root fillings used with AH Plus or a flowable MTA sealer
No full textAim
To investigate nondestructively the percentage of 3D voids and marginal gaps in a pre-defined interface volume of interest (VOI) within root fillings produced by Thermafil Obturators with either a hydrophobic epoxy-resin-based sealer (AH Plus) or a hydrophilic flowable calcium-silicate sealer [mineral trioxide aggregate (MTA) Flow].
Methodology
Sixteen single root canals from extracted premolar teeth were prepared with ProTaper rotary instruments, randomly allocated into two groups (n = 8) and filled with size 30 Thermafil Obturators in association with AH Plus or MTA Flow sealers. The filled roots were stored at 37 °C in 5 mL of Hank's balanced salt solution (HBSS) used to represent body fluids and scanned after 7 days and 6 months using a high-resolution micro-CT. From each root, images of 3000 sections were analysed in 3D and binarized using a high-resolution micro-CT (4-μ resolution). The 3D distribution of voids (porosity and marginal gaps) at the gutta-percha-sealer-dentine interface was detected through a threshold grey level and expressed as percentage of the 40-μ-thick pre-defined interface VOI (20 μ of interface dentine and 20 μ of gutta-percha/sealer). A method of analysis based on the root canal segmentation was used, and coronal, middle and apical thirds considered separately. The percentage of 3D void volume was compared statistically using one-way anova (significance for P < 0.05). Environmental Scanning Electron Microscope with Energy Dispersive X-ray (ESEM-EDX) analysis was performed on the surface of both sealers after soaking in HBSS.
Results
Micro-CT detected gaps at the dentine-sealer interface in both groups. Void volumes wider than 10.21 μm3 with 1.35 μm diameter were detected. Cul-de-sac-type voids (blind pores) and through-and-through voids (continuous pores) were discriminated. The apical thirds had a significantly lower 3D void volume (P < 0.05) than the middle and coronal thirds. The 3D void volume reduced significantly (P < 0.05) over time. ESEM-EDX analysis revealed that MTA Flow sealer created a dense apatite layer after 7 days of immersion in HBSS, whilst only sparse calcium phosphate deposits were detected on AH Plus even after 28 days.
Conclusions
Micro-CT proved to be a powerful nondestructive 3D analysis tool for visualizing the porous internal microstructure of dental/endodontic materials at the interface with dentine. The proportion of voids was least in the apical third of root canals. Voids reduced over time in the presence of simulated body fluid
A preliminary assessment of a new dedicated endodontic software for use with CBCT images to evaluate the canal complexity of mandibular molars
No full textAim To investigate in vivo the complexity of canals
within mesial roots of mandibular molars using 3D
EndoTM software linked to CBCT images.
Methodology The CBCT images of 100 mandibular
first molars were analysed using the 3D EndoTM
software. The number of canals in the mesial roots,
the presence of apical confluences, the canal lengths
and the canal configurations using Vertucci’s classification
were evaluated in buccolingual (BL) and
mesiodistal (MD) views. The software allowed the
visualization of canal trajectories in three dimensions
using a coloured outline, which was used to develop
a new objective scoring system to provide an overall
assessment of canal complexity. Data were analysed
statistically using ANOVA and t-tests with the significance
set at P < 0.05.
Results Vertucci type IV canals were found in 44% of
the cases, whilst 54% were type II. The mean distance
from the apical foramen to the orifice was 13.15 mm
(1.21) and that between a confluence and the foramen,
2.81 mm (1.13). The number of curvatures and the
canal complexity scores in the MD view were significantly
higher than in the BL view (P < 0.05). The scores
were not directly correlated to the canal (MB versus ML),
to the canal length or to the presence of confluences.
Conclusions 3D Endo software features the automatic
detection and measurement of several anatomical
canal parameters, and is a promising tool for the
study of canal complexity in vivo. The unpredictable
anatomy of the mesial roots of mandibular molars
highlights the value of a three-dimensional preoperative
evaluation of each case. The proposed scoring
system aims to provide the clinician with an overall
assessment of canal complexity
Microstructure and chemical analysis of blood-contaminated mineral trioxide aggregate
No full textNekoofar MH, Davies TE, Stone D, Basturk FB, Dummer PMH. Microstructure and chemical analysis of blood-contaminated MTA. International Endodontic Journal, 44, 1011-1018, 2011. Aim To test the hypothesis that blood contamination has a detrimental effect on the chemical properties of Mineral trioxide aggregate (MTA). Methodology The effects of whole, fresh human blood on the microstructure and elemental chemistry of MTA were evaluated using scanning electron microscopy and energy-dispersive X-ray analysis, respectively. The phase compositions of contaminated and uncontaminated MTA were also analysed using X-ray diffraction analysis. Results The hydration state of specimens partially mixed with blood were more complete than those mixed entirely with blood and less than those entirely mixed with water. Acicular crystals. characteristic of ettringite, were abundant in specimens mixed entirely with water and absent from specimens mixed partially or entirely with blood. Calcium hydroxide crystals were absent in specimens contaminated entirely with blood and the unhydrated NITA powder, but present in the other groups. Conclusion Mixing MTA with blood resulted in the lack of formation of the crystalline calcium hydroxide in the early stage of the hydration process
How is Endodontics taught? A survey to evaluate undergraduate endodontic teaching in dental schools within the United Kingdom
No full textAim
To evaluate the delivery of undergraduate endodontic education in UK dental schools using an online survey and to compare the results with those of a previous paper‐based survey (Qualtrough & Dummer 1997, Int Endod J, 30, 234). Aspects of delivery were also evaluated in comparison with the Undergraduate Curriculum Guidelines of the European Society of Endodontology (de Moor et al. 2013, Int Endod J, 46, 1105).
Methodology
An online version of an earlier paper‐based survey on undergraduate Endodontic education (Qualtrough & Dummer 1997, Int Endod J, 30, 234) was created. Invitations to take part were sent via email to the undergraduate endodontic programme leads in the 16 UK dental schools.
Results
The response rate was 94%. The current survey revealed greater convergence amongst dental schools than previously (Qualtrough & Dummer 1997, Int Endod J, 30, 234) on methods of canal preparation, disinfection and filling. Improvements were also noted in staff: student ratios, the involvement of teachers with advanced endodontic training and a greater diversity of teaching methods; developments which align with the recommendations of ESE Undergraduate Curriculum Guidelines (de Moor et al. 2013, Int Endod J, 46, 1105). The majority of schools appeared to be teaching contemporary instrumentation methods and were recommending the application of calcium silicate cements. The exposure of students to advanced topics included in the ESE Undergraduate Curriculum Guidelines (de Moor et al. 2013, Int Endod J, 46, 1105) such as surgical endodontic treatment, root canal re‐treatment and the management of complex cases was mixed.
Conclusion
Undergraduate endodontic training in the UK has advanced in the last 20 years with more consistency between schools and more contemporary methods adopted
European Society of Endodontology position statement: the use of antibiotics in endodontics
No full textThis position statement represents a consensus of an expert committee convened by the European Society of Endodontology (ESE) on Antibiotics in Endodontics. The statement is based on current scientific evidence as well as the expertise of the committee. The goal is to provide dentists and other healthcare workers with evidence-based criteria for when to use antibiotics in the treatment of endodontic infections, traumatic injuries of the teeth, revascularization procedures in immature teeth with pulp necrosis, and in prophylaxis for medically compromised patients. It also highlights the role that dentists and others can play in preventing the overuse of antibiotics. A recent review article provides the basis for this position statement and more detailed background information (International Endodontic Journal, 2017, https://doi.org/10.1111/iej.12741). Given the dynamic nature of research in this area, this position statement will be updated at appropriate intervals
Altmetric analysis of the contemporary scientific literature in Endodontology
No full textAim
To analyse and visualize the knowledge structure of scientific articles in the field of Endodontology with high altmetric attention scores to discover hot topics, active researchers and the journals involved.
Methodology
On 5 June 2019, the altmetric database (Altmetric LLP, London, UK) was searched using the titles of 11 endodontic journals. Bibliometric data from endodontic articles and journals with an altmetric score >5 (top 5%) were retrieved from PubMed and analysed using the VOSviewer. Science mapping of articles with an altmetric score >5 at two levels was created: author keywords co‐occurrence and co‐authorship network analysis.
Results
Of the 2197 articles in the field of Endodontology identified with altmetrics, 192 had altmetric scores >5 (top 5%). Considering the total mentions amongst all altmetric resources, the Journal of Endodontics had the highest rank followed by the International Endodontic Journal and Australian Endodontic Journal. Twitter was the most popular altmetric data resource followed by patents and Facebook. Meta‐analysis, systematic review and pulpitis were the hot topics. At the author level, Dummer P.M.H had the greatest influence on the network. There was no significant correlation between altmetric score and citations count (P > 0.05). Mendeley mentions correlated with citations (P < 0.05).
Conclusions
Overall, the altmetric scores of topics within Endodontology were low, possibly due to the specific and specialized nature of the specialty, as well as the difficulty members of the public probably have in understanding endodontic research. Journals and researchers with a focus on Endodontology would have more influence if they were to set‐up their own social media profiles and thus enhance their visibility and social impact by immediately sharing research findings and communicating with their network and audience
The safety and effectiveness of different methods of ear wax removal: a systematic review and economic evaluation
No full textEar wax (cerumen) is a natural secretion produced to protect the inner ear from dirt and other fragments by moving these particles towards the outer ear. If this process does not happen properly, wax may build up causing blockage in the ear canal and the possibility of impaction. People with a build up of ear wax may suffer from hearing loss, discomfort and, on occasions, infection. It may present problems in assessing hearing, blocking the view of the ear drum during medical examination and interfering with the fitting or function of hearing aids. Although it is thought to affect between 2% and 6% of the population in the England and Wales, some groups may be at a higher risk, such as those using hearing aids or with small ear canals and/or skin conditions. Recurrence is thought to be high among some of these groups. The consequences of the build up of ear wax in the ear canal are thought to be a common reason for consultation and cost in general practice with over 2 million consultations per year in the NHS.Methods of removal of ear wax include drops, flushing with water in general practice, and removal with suction or probes in specialist clinics. The relative safety and benefits of these different methods of removal remains uncertain. This research will systematically review published and unpublished evidence on the clinical and cost effectiveness of different methods for the removal of ear wax. Where appropriate, it will develop an economic model using data from this systematic review and other relevant sources to estimate the relative costs and benefits of different methods. In addition, the project will provide recommendations for future research to try to help answer any remaining areas of uncertainty
Accreditation of postgraduate speciality training programmes in Endodontology. Minimum criteria for training Specialists in Endodontology within Europe.
No full textThis consensus statement from the European Society of Endodontology (ESE) sets out the minimum criteria for training Specialists in Endodontology within Europe. The case is made for recognizing Endodontology as a distinctive dental discipline throughout Europe. Guidelines are presented on the requirements of a specialist and of a specialist training programme in Endodontology. The aims, objectives and curriculum content of a specialist training pathway are outlined, with guidelines on trainee appraisal, and the expectations of faculty and institutional commitment. In publishing these guidelines, the ESE is responding to a public and professional need for consistently high standards of training and specialist clinical service within Europe
A study of endodontic treatment carried out in dental practice within the UK
No full textAbstract Jenkins SM, Hayes SJ, Dummer PMH. A study of endodontic treatment carried out in dental practice within the UK. International Endodontic Journal , 34 , 16-22, 2001. Aim The purpose of this study was to gather both qualitative and quantitative information on the nature of root canal treatment carried out by a group of dentists working within the United Kingdom. Methodology A two-part questionnaire was posted to 720 dentists who graduated from the Dental School, Cardiff, Wales, UK. The first part requested basic information regarding age, year of qualification, field of practice, etc. The second part consisted of 15 questions on endodontic practice and root canal treatment. Results The response rate was 41.5%. Two hundred and ninety-nine questionnaires contained useful information. The majority of practitioners did not use rubber dam during root canal treatment. The vast majority (89%) exposed a radiograph with an instrument of known length in situ to gauge the 'working length', a small number relied upon tactile sensation. Most practitioners used local anaesthetic solution as an irrigant during instrumentation of the root canal. A wide variety of instruments were used for root canal treatment; a stepback technique was preferred by almost half the practitioners. Antiseptic solution was preferred as an interappointment dressing. More than half of the respondents used laterally condensed gutta-percha to obturate root canals in anterior teeth but only one-third used the same technique in posterior teeth. Less than half the respondents exposed a radiograph to check the fit of the master point prior to obturation. Two-thirds of practitioners used a zinc oxide based material as their root canal sealer. Threequarters of the practitioners exposed a post obturation radiograph. Conclusions The results of this study suggest that although some dentists are using the techniques taught during their undergraduate careers, a large percentage now use techniques with no evidence of clinical effectiveness
X-ray diffraction analysis of MTA mixed and placed with various techniques
No full textObjectives The aim of this study was to evaluate the effect of various mixing techniques as well as the effect of ultrasonic placement on hydration of mineral trioxide aggregate (MTA) using X-ray diffraction (XRD) analysis. Materials and methods One gram of ProRoot MTA and MTA Angelus powder was mixed with a 0.34-g of distilled water. Specimens were mixed either by mechanical mixing of capsules for 30 s at 4500 rpm or by manual mixing followed by application of a compaction pressure of 3.22 MPa for 1 min. The mixtures were transferred into the XRD sample holder with minimum pressure. Indirect ultrasonic activation was applied to half of the specimens. All specimens were incubated at 37 degrees C and 100% humidity for 4 days. Samples were analyzed by XRD. Phase identification was accomplished by use of search-match software utilizing International Centre for Diffraction Data (ICDD). Results All specimens comprised tricalcium silicate, calcium carbonate, and bismuth oxide. A calcium hydroxide phase was formed in all ProRoot specimens whereas among MTA Angelus groups, it was found only in the sample mixed mechanically and placed by ultrasonication. Conclusions Mechanical mixing followed by ultrasonication did not confer a significant disadvantage in terms of hydration characteristics of MTA
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