ORCID Profile
0000-0002-8208-0045
Current Organisations
Endodontic Apps
,
Endogear Australia
,
University of Adelaide
,
University of Sydney
,
European Endodontic Journal
,
NSW Health
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Publications
Classification and Nomanclature of Commercial Hygroscopic Dental Cements
Publisher: Kare Publishing
Date: 20-10-2017
Mineral Trioxide Aggregate—A Review of Properties and Testing Methodologies
Publisher: MDPI AG
Date: 02-11-2017
DOI: 10.3390/MA10111261
A Systematic Review Comparing Mineral Trioxide Aggregate to Other Commercially Available Direct Pulp Capping Agents in Dogs
Publisher: SAGE Publications
Date: 03-2021
DOI: 10.1177/08987564211024905
Abstract: Vital pulp therapy (VPT) and direct pulp capping (DPC) are procedures regularly performed in dogs for the management of acute tooth fractures and as part of management for traumatic malocclusions. The purpose of this review is to apply an evidence-based medicine approach to systematically review and evaluate the scientific literature evaluating the efficacy of mineral trioxide aggregate (MTA) to other commercially available materials used for VPT in the permanent teeth of dogs. The 9 studies meeting inclusion criteria were reviewed and each studies evidence was classified using a grading system modified from the Oxford Centre for Evidence-Based Medicine. For the studies meeting inclusion criteria, MTA consistently performed as well or better than other commercially available products in terms of calcific barrier formation and biocompatibility. This review found a lack of consistency between the studies making a direct comparison of the results unreliable. Future studies would benefit from the implementation of a standard scoring system for histology, equivalent and longer study duration times and the correlation of histological and radiographic data.
Particle Size Changes in Unsealed Mineral Trioxide Aggregate Powder
Publisher: Elsevier BV
Date: 03-2014
DOI: 10.1016/J.JOEN.2013.10.018
Abstract: Mineral trioxide aggregate (MTA) is commonly supplied in 1-g packages of powder that are used by some clinicians across several treatments against the manufacturer's instructions. ProRoot MTA cannot be resealed after opening, whereas MTA Angelus has a resealable lid. This study assessed changes in particle size distribution once the packaging had been opened. Fresh ProRoot MTA and MTA Angelus powder were analyzed by using laser diffraction and scanning electron microscopy and compared with powder from packages that had been opened once and kept in storage for 2 years. The ProRoot packet was folded over, whereas the MTA Angelus jar had the lid twisted back to its original position. After 2 years, ProRoot MTA powder showed a 6-fold increase in particle size (lower 10% from 1.13 to 4.37 μm, median particle size from 1.99 to 12.87 μm, and upper 10% from 4.30 to 34.67 μm), with an accompanying 50-fold change in particle surface area. MTA Angelus showed only a 2-fold increase in particle size (4.15 to 8.32 μm, 12.72 to 23.79 μm, and 42.66 to 47.91 μm, respectively) and a 2-fold change in particle size surface area. MTA reacts with atmospheric moisture, causing an increase in particle size that may adversely affect the properties and shelf life of the material. Smaller particles have a greater predisposition to absorb moisture. Single-use systems are advised.
An Arithmetic Crown-down Dynamic Tactile Instrumentation Technique: A Case Report of an S-shaped Root Canal
Publisher: Elsevier BV
Date: 05-2021
Comparative Evaluation of Mineral Trioxide Aggregate Obturation Using Four Different Techniques—A Laboratory Study
Publisher: MDPI AG
Date: 07-06-2021
DOI: 10.3390/MA14113126
Abstract: This study aimed to compare the density of mineral trioxide aggregate (MTA) as a root canal filling material in the apical 5 mm of artificial root canals. Forty transparent acrylic blocks with 30-degree curved canals were instrumented and allocated into four compaction technique groups (n = 10): Lawaty (hand files) gutta-percha (GP) points auger (nickel–titanium rotary files in reverse mode) and plugger technique. Filled canals were weighed after setting the MTA to calculate difference in mass. Two postoperative radiographs compared radiopacity by measuring luminance variations at 0.5 mm, 1 mm, 2 mm, 3 mm, 4 mm, and 5 mm from the root apex. Obturation time was measured using a digital chronometer. The significance level was set to p 0.05. The plugger group had a lower mass. Relative luminance was significantly higher for the Lawaty group than the plugger group at all examined apical levels. The relative luminance of the auger and GP groups were significantly higher than the plugger group at depths between 0.5 mm and 2 mm. Relative luminance was highest for the Lawaty technique at all depths between 0.5 mm and 4 mm. The Lawaty technique group was associated with increased obturation time compared with pluggers. Compacting MTA in curved canals with the Lawaty technique has the highest mass and radiopacity but requires more time.
The effect of a preparation containing glycocholic acid on the biocidal efficacy of sodium hypochlorite in a biofilm laboratory model
Publisher: Wiley
Date: 05-07-2023
DOI: 10.1111/AEJ.12771
Abstract: This study assessed the antimicrobial effect of sodium hypochlorite (NaOCl) mixtures combined with Keratobacter (KB) using an engineered biofilm root canal model. Clinical and reagent grade NaOCl were mixed with KB (9:1‐vol/vol) to assess pH values over 1 min to select the ideal solution with a pH just below the pKa of hypochlorous acid. The s les were randomly ided into five groups: 1% and 4% NaOCl reagents, a mixture of NaOCl:KB using 1% and 4% NaOCl reagents and distilled water. Outcome measures were colony‐forming units (CFUs/mL) and positive/negative cultures. No significant differences were observed in the pairwise comparisons between 1%, 4% NaOCl and 4% NaOCl+KB for the outcome CFUs/mL. Only 4% NaOCl presented with negative cultures in all s les, whereas 1% NaOCl and 4% NaOCl+KB had similar results (54% vs. 40%). The addition of KB has a limited effect on the antimicrobial efficacy of 4% NaOCl in this laboratory model.
Rheological Characterization as an Alternative Method to Indentation for Determining the Setting Time of Restorative and Endodontic Cements
Publisher: MDPI AG
Date: 20-12-2017
DOI: 10.3390/MA10121451
Cone-beam computed tomography—Predictors and characteristics of usage in Australia and New Zealand, a multifactorial analysis
Publisher: Wiley
Date: 13-07-2022
DOI: 10.1111/AEJ.12663
Abstract: Cone‐beam computed tomography ( CBCT ) is an increasingly used imaging modality. This study aimed to identify the factors that predict its usage amongst endodontists in Australia and New Zealand and describe usage characteristics. Data were collected via an online questionnaire, with analysis including descriptive statistics, cross‐tabulation and multifactorial modelling. Ninety‐four endodontists completed the questionnaire who were using CBCT for 7 years (median), over half had a CBCT unit in practice, with most prescribing up to 10 scans/month and 55 using a small field of view. Sixty‐eight participated in h of CBCT education/year and a third received a specialist‐prepared report. The number of prescriptions/month was significantly associated with on‐site CBCT units (Exp B: 8.53 95% CI : 1.46–49.86, p 0.05) and the number of years of CBCT usage by participants (Exp B: 1.46 95% CI : 1.17–1.84, p = 0.001). CBCT imaging in endodontics is a useful diagnostic aid to decision making and treatment planning, with widespread acceptance and usage.
Parallel endodontic education via social media: An exploratory survey study
Publisher: Wiley
Date: 13-07-2023
DOI: 10.1111/AEJ.12773
Abstract: There is insufficient research to evaluate social media's influence on endodontic education. Therefore, this study assessed the percentage of students utilising Facebook in their education and the factors influencing their engagement. A survey was conducted on dental students, interns and dentists undertaking specialist programmes. Categorical data were analysed using Fisher's Exact test and multiple pairwise comparisons. The significance level was set at p 0.05. Responses were received from 801 participants, with 98.4% using Facebook for endodontic knowledge. Although most students knew that scientific evidence is not always provided, they still deemed such information valuable as it was a practical demonstration of clinical cases. Most students turn to Facebook for endodontic education to compensate for the gap between their academic education and clinical practice. The utilisation of social media for education can be a concerning phenomenon and should not be ignored by academic institutes.
D90: The Strongest Contributor to Setting Time in Mineral Trioxide Aggregate and Portland Cement
Publisher: Elsevier BV
Date: 07-2015
DOI: 10.1016/J.JOEN.2015.02.033
Abstract: The setting times of commercial mineral trioxide aggregate (MTA) and Portland cements vary. It was hypothesized that much of this variation was caused by differences in particle size distribution. Two gram s les from 11 MTA-type cements were analyzed by laser diffraction to determine their particle size distributions characterized by their percentile equivalent diameters (the 10th percentile, the median, and the 90th percentile [d90], respectively). Setting time data were received from manufacturers who performed indentation setting time tests as specified by the standards relevant to dentistry, ISO 6786 (9 respondents) or ISO 9917.1 (1 respondent), or not ulged to the authors (1 respondent). In a parallel experiment, 6 s les of different size graded Portland cements were produced using the same cement clinker. The measurement of setting time for Portland cement pastes was performed using American Society for Testing and Materials C 191. Cumulative heat release was measured using isothermal calorimetry to assess the reactions occurring during the setting of these pastes. In all experiments, linear correlations were assessed between setting times, heat release, and the 3 particle size parameters. Particle size varied considerably among MTA cements. For MTA cements, d90 was the particle size characteristic showing the highest positive linear correlation with setting time (r = 0.538). For Portland cement, d90 gave an even higher linear correlation for the initial setting time (r = 0.804) and the final setting time (r = 0.873) and exhibited a strong negative linear correlation for cumulative heat release (r = 0.901). Smaller particle sizes result in faster setting times, with d90 (the largest particles) being most closely correlated with the setting times of the s les.
Rapidly progressing generalised tooth resorption associated with primary immunodeficiency due to XIAP /BIRC4 mutation: A case report
Publisher: Wiley
Date: 12-11-2022
DOI: 10.1111/IPD.13034
Abstract: Primary immunodeficiency (PID) with a mutation in the X-linked inhibitor of apoptosis protein (XIAP/BIRC4) is a rare congenital condition characterised by haemophagocytic lymphohistiocytosis (HLH). Dental anomalies for this condition are not well documented in the literature. We report an unusual case of generalised, rapid resorption of all primary teeth in a 7-year-old boy. Affected teeth were extracted to avoid potential pulpal and periapical infection. Combined clinical assessment, plain film radiograph, microcomputed tomography and histopathology enabled the identification of macroscopic and microscopic features associated with the rapid resorption, including gross infiltration of calcific material inside the enlarged pulp space. This case documents the importance of regular clinical and radiographic review in primary immune deficiency XIAP/BIRC4, as well as the need to better understand the pathogenesis of rapid resorption to inform clinical care.
Dental Material Choices for Pulp Therapy in Paediatric Dentistry
Publisher: Kare Publishing
Date: 02-2017
A survey of various endodontic procedures related to mineral trioxide aggregate usage by members of the Australian Society of Endodontology
Publisher: Wiley
Date: 15-09-2016
DOI: 10.1111/AEJ.12170
Abstract: This study aims to assess education on the use of mineral trioxide aggregate (MTA) and Biodentine among members of the Australian Society of Endodontology (ASE), a society of specialist endodontists (ED) and general dentists with an interest in endodontics (GD). The study also aims to compare the procedural preferences relating to perforation repair, apical barrier, root-end filling and regenerative endodontics. A structured online questionnaire was used, which sought details of the education in the use of MTA and the procedural steps involved in perforation repair, apical barrier, root-end filling and regenerative endodontics. Fisher's exact test was performed to compare the GD with ED. Responses were received from 208 out of 499 ASE members. Some 40% of the total respondents were ED. Almost all ED (98.8%) and some GD (39.8%) used MTA for perforation repairs. Likewise, almost all ED (96.3%) and some GD (42.7%) used MTA for apical barrier procedures. Lack of experience was more of a barrier to its use for GD (48.7%) than its high cost (31.6%). Few members used Biodentine. Significant differences exist in how MTA is used between GD and ED. Experience in handling MTA is a larger barrier to its widespread use in endodontics than its cost.
Microbial contamination comparison between cotton pellet and polytetrafluoroethylene tape endodontic spacers: a systematic review
Publisher: Kare Publishing
Date: 2021
The influence of particle size and curing conditions on testing mineral trioxide aggregate cement
Publisher: Informa UK Limited
Date: 05-10-2016
What is new in the 2020 International Association of Dental Traumatology emergency treatment guidelines?
Publisher: Wiley
Date: 13-03-2021
DOI: 10.1111/EDT.12671
A retrospective analysis of oral and maxillofacial pathology in an Australian paediatric population
Publisher: Wiley
Date: 26-05-2014
DOI: 10.1111/ADJ.12174
Abstract: The prevalence of oral and maxillofacial pathology has not previously been reported in the Australian paediatric population. This study aimed to audit a large pathology service to provide insight into the prevalence of oral and maxillofacial pathology. Written records of a major Australian oral pathology service were imported into an electronic database. Age, gender and histological diagnosis were assessed. Prevalence of histological diagnoses as a percentage of the major diagnostic categories and of the whole s le were calculated, as well as gender predilections and mean age of presentation of disease. A total of 1305 oral pathology specimens, collected from paediatric patients aged 16 and under were included in the analysis. The most common pathology was dental pathology (24.4%), followed by odontogenic cysts (18.5%) and mucosal pathology (17.0%). The most frequently encountered lesion was the dentigerous cyst (9.4%), followed by fibrous hyperplasia (8.3%), radicular cyst (5.2%) and chronic periapical granuloma (5.2%). In the paediatric population, dental pathology and specifically, the dentigerous cyst is the most common pathology type sent for histopathology, suggesting a high prevalence of pathology of dental origin occurring in Australian children.
The effects of sodium hypochlorite and ethylenediaminetetraacetic acid on the microhardness of Mineral Trioxide Aggregate and TotalFill Bioceramic Putty
Publisher: Wiley
Date: 03-05-2019
DOI: 10.1111/AEJ.12352
Abstract: This study aimed to evaluate the effects of 5% NaOCl and 17% EDTA on the Vickers microhardness of Mineral Trioxide Aggregate, MTA Angelus (MTAA), and TotalFill Bioceramic Putty (BCP) after 24 h and 8 days. Twenty-four s les of MTAA and BCP were tested for baseline microhardness at 24 h. They were ided into four subgroups (5% NaOCl or 17% EDTA, 24 h, 5% NaOCl or 17% EDTA at 8 days) and microhardness was evaluated at different time-points. Results were recorded and analysed statistically via one-way anova Kruskal-Wallis test and post hoc uncorrected Dunn's multiple comparison test. MTAA had a higher baseline microhardness than BCP. NaOCl reduced the microhardness of MTAA but increased that of BCP. EDTA reduced the microhardness for both materials at 24 h. At 8 days, EDTA reduced the microhardness of MTAA, while BCP exhibited an increase in microhardness. Enabling these materials to set for a week prior to exposure to irrigants improves their microhardness.
A retrospective analysis of oral and maxillofacial pathology in an Australian adult population
Publisher: Wiley
Date: 26-05-2014
DOI: 10.1111/ADJ.12175
Abstract: The prevalence of oral and maxillofacial pathology has not previously been reported in the Australian adult population. This study aimed to audit a large pathology service to provide insight into the prevalence of head and neck pathologies. Written records of a major Australian oral pathology service were imported into an electronic database. Age, gender and histological diagnosis were assessed. Prevalence of histological diagnoses as a percentage of the major diagnostic categories and of the whole s le were calculated, as well as gender predilections and mean age of presentation of disease. A total of 6344 oral pathology specimens, collected from adults aged 17 years and over were included in the analysis. Mucosal pathology was the most common pathology (37.2%), followed by odontogenic cysts (16.3%) and dental pathology (14.5%). The three most common histological diagnoses were fibrous hyperplasia (15.2%), chronic periapical granuloma (9.6%) and radicular cyst (9.5%). The male:female ratio of the entire s le was 0.74. This is the first study to describe the prevalence of oral and maxillofacial pathology among adult patients in an Australian population. The trends seen in this study are repeated in studies from other parts of the world, and are of diagnostic importance.
Do zirconia single-retainer resin-bonded fixed dental prostheses present a viable treatment option for the replacement of missing anterior teeth? A systematic review and meta-analysis
Publisher: Elsevier BV
Date: 10-2023
DOI: 10.1016/J.PROSDENT.2021.10.015
Abstract: Zirconia has been widely used in restorative dentistry because of its favorable strength and esthetics. However, its polycrystalline structure presents a challenge for resin bonding. Significant research into surface treatments of zirconia to improve bonding has been reported, yet a universally accepted protocol remains elusive. The purpose of this systematic review and meta-analysis was to evaluate the performance of anterior single-retainer zirconia resin-bonded fixed dental prostheses (RBFDPs) and review the bonding protocols used in the published data. An electronic search of English language literature was conducted in the PubMed and Ovid (MEDLINE) databases. Following the application of inclusion and exclusion criteria, the research was evaluated to assess the quantitative data. Of the included studies, 1 randomized controlled trial, 3 prospective cohort studies, and 2 retrospective cohort studies reporting on anterior single-retainer zirconia RBFDPs were evaluated. Over a 3- to 10-year period, the success rate of anterior single-retainer zirconia RBFDPs was over 80%. Although there were reports of debonds, this is a minor complication as rebonding is usually possible. Furthermore, catastrophic fractures of the entire prosthesis were rare. Evidence for the use of single-retainer zirconia RBFDPs as a suitable treatment option for the replacement of anterior missing teeth is considerable. Based on the findings of this systematic review and meta-analysis, a 2-step process comprising micromechanical retention using airborne-particle abrasion and subsequent resin-zirconia adhesion by the application of 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP) can be recommended.
Methodologies for measuring the setting times of mineral trioxide aggregate and Portland cement products used in dentistry
Publisher: Informa UK Limited
Date: 26-01-2016
Prevalence and morphological features of molar‐root incisor malformation in children attending a specialist paediatric dental unit
Publisher: Wiley
Date: 10-03-2023
DOI: 10.1111/IPD.13061
Abstract: Molar‐root incisor malformation (MRIM) is a rare dental anomaly featuring constricted cervical margins and tapered, narrow root and pulp morphology, often associated with severe toothache and infection. The aim of this study was to determine the prevalence of MRIM in children seen in a specialist paediatric dental unit of a tertiary referral hospital and to describe the characteristics of affected in iduals. This study was an audit of children attending from November 2020 to November 2021. Radiographs were used to identify in iduals with MRIM, and clinical data were collated. In addition, histology and microcomputed tomography (microCT) imaging were performed on teeth extracted from an affected in idual. The prevalence of MRIM was five cases of 1054 children examined (0.47% or 1:210). The permanent first molars were affected in all five children and the primary second molars in two children all children had medical comorbidities and multiple exposures to general anesthesia before 4 years of age. In addition, histological and microCT analyses displayed numerous microchannels connecting the pulp chamber to the external surface of the tooth at the furcation. Molar‐root incisor malformation is an uncommon dental anomaly affecting paediatric patients with multiple comorbidities and is characterized by porosities extending from the pulp chamber to the external tooth surface, predisposing the risk of bacterial ingress from the oral cavity into the pulp chamber. Early detection may prevent atypical odontogenic facial pain and infection.
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