Peter Parashos - Academia.edu (original) (raw)
Papers by Peter Parashos
Dental research journal, 2023
Australian Endodontic Journal
International Endodontic Journal
Observational studies are non‐interventional studies that establish the prevalence and incidence ... more Observational studies are non‐interventional studies that establish the prevalence and incidence of conditions or diseases in populations or analyse the relationship between health status and other variables. They also facilitate the development of specific research questions for future randomized trials or to answer important scientific questions when trials are not possible to carry out. This article outlines the previously documented consensus‐based approach by which the Preferred Reporting items for Observational studies in Endodontics (PROBE) 2023 guidelines were developed. A steering committee of nine members was formed, including the project leaders (PD, VN). The steering committee developed an initial checklist by combining and adapting items from the STrengthening the Reporting of Observational studies in Epidemiology (STROBE) checklist and the Clinical and Laboratory Images in Publications (CLIP) principles, as well as adding several new items specifically for the specialt...
Journal of the Mechanical Behavior of Biomedical Materials
The objectives of this study were to evaluate 4 aspects of ion-leaching restorative materials (IL... more The objectives of this study were to evaluate 4 aspects of ion-leaching restorative materials (ILMs): 4-point bending flexural strength (4 PB-FS) and relative mechanical properties; biaxial flexural strength (B-FS) in relation to 4 PB-FS; porosity; and surface morphology. Eleven ILMs were used for the 4-point bending test. Bar-shaped (n = 15) samples were fabricated, stored in distilled water for 7 days. Then 4 PB-FS and the other mechanical properties were determined. Five ILMs were selected for the B-FS test using disk specimens (n = 15). The correlation between 4 PB-FS and B-FS was addressed. After the 4 PB test, 5 randomised fragments from each material were used to make 0.5 mm-thick sections for light microscopy to investigate the degree of porosity using reflected and transmitted lights. Eight ILMs were selected for quantitative analysis of the fractional % pore volume (PV%) due to their relative pore prominence using ImageJ software. One-way ANOVA/Dunnett's T3 was used to test for significance. Resin-based ILMs (RB-ILMs) were ranked first (p < 0.05) for 4 PB-FS values (53.3-110.2 MPa) followed by resin-modified glass-ionomer cements (RMGICs; 30.9-44.3 MPa) and high-viscosity glass-ionomer cements (HVGICs; 12.9-19.6 MPa), respectively. 'Flexural modulus' (4 PB-E) and 'flexural toughness' (4 PB-T) of ILMs varied even though similar 4 PB-FS values were observed. There was a positive correlation (p < 0.001) between 4PB-FS and B-FS (R2 = 0.992) with B-FS>4 PB-FS. There was no correlation between PV% and 4 PB-FS. In summary, material type played a major role in 4 PB-FS outcomes, whereas PV% seemed to have a minor effect when evaluating each material group of ILMs. Brittleness/ductility of ILMs was observed when determining 4 PB-E and 4 PB-T relative to 4 PB-FS. When selecting materials for posterior load-bearing dental restorations in high-caries risk patients, RB-ILMs or RMGICs would be more appropriate due to their superior flexural properties compared with recently introduced HVGICs. The decision for each situation will also be dependent on further evidence of the ion-leaching capacity.
Australian Dental Journal
BackgroundPeople with special health care needs continue to have difficulties accessing regular d... more BackgroundPeople with special health care needs continue to have difficulties accessing regular dental care partly due to oral health professionals feeling they lack the knowledge and experience to provide treatment to these individuals.MethodsQualitative interviews and focus groups provided an insight into the types and nature of supports that oral health professionals working in the Australian public dental system desired and felt may improve their willingness and/or ability to treat patients with special needs.ResultsAlthough participants did not identify one group of patients with special needs that were more difficult to treat, they did report a feeling of being unsupported. Clinicians felt that improved training and access to ongoing education in Special Needs Dentistry, opportunities for greater support from specialists or other health professionals, either through networking or other media such as telehealth, and fostering a more supportive clinical environment, particularly...
Australian Dental Journal, 2022
BACKGROUND Canalis sinuosus (CS) and its relationship with adjacent teeth is relevant for surgery... more BACKGROUND Canalis sinuosus (CS) and its relationship with adjacent teeth is relevant for surgery in the anterior maxilla. Therefore, the aim of this study was to report the prevalence, characteristics, and variations of CS. METHODS Cone beam computed tomography (CBCT) scans of the anterior maxilla of 201 patients were reviewed. CS and the adjacent teeth were analysed by age, sex, and scan resolution, using analysis of variance, chi-squared and Fisher's exact tests. The widest and narrowest diameters of CS, and distance to tooth apex (DTA), were compared by quadrant, closest tooth, and location, and the associations were examined statistically with P < 0.05. RESULTS In the 201 scans, 412 CS were identified in 198 patients associated with 395 different teeth. Mean widest diameter was 1.08 ± 0.39 mm (range: 0.42-2.60 mm), while the narrowest diameter was 0.71 ± 0.26 mm (range: 0.25-1.59 mm), and mean DTA of 2.16 ±1.25 mm (range: 0-6.22 mm). CS detection was significantly lower with CBCT taken at resolution size of 0.250 voxels (P = 0.02). CONCLUSIONS CS was very common in the anterior maxilla. Clinicians would be well advised to identify this anatomical structure using CBCT before undertaking any surgery in the anterior maxilla. © 2022 Australian Dental Association.
Journal of Endodontics, 2021
INTRODUCTION This study assessed the prevalence of radix entomolaris and two canals at the distal... more INTRODUCTION This study assessed the prevalence of radix entomolaris and two canals at the distal aspect of mandibular first molars amongst different geographic regions by means of cone-beam computed tomography (CBCT). METHODS Pre-calibrated observers from 23 worldwide geographic locations followed a standardized screening protocol to assess 5,750 CBCT images of mandibular first molars (250 per region) gathering demographic data and recording the presence of radix entomolaris and a second canal at the distal aspect of teeth. Intra- and inter-rater reliability tests were conducted and comparisons amongst groups were performed using proportions and odds ratio forest plots. Significance level was set at 5%. RESULTS Results of intra- and inter-rater tests were above 0.79. The prevalence of radix entomolaris varied from 0.9% in Venezuela (0%-1.9%, CI 95%) to 22.4% in China (17.2%-27.6%, CI 95%). Regarding the proportion of a second distal canal, it ranged from 16.4% in Venezuela (11.8%-21.0%, CI 95%) to 60.0% in Egypt (53.9%-66.1%, CI 95%). East Asia subgroup was associated with significantly higher prevalence of an extra distolingual root, while America subgroup, American native ethnic group and elderly patients were linked to significantly lower percentages of a second canal at the distal aspect of teeth. No significant differences were noted between male or female patients. CONCLUSIONS The overall worldwide prevalence of radix entomolaris and a second canal at the distal aspect of the mandibular first molar were 5.6% and 36.9%, respectively. East Asia geographic region and Asian ethnic group had higher prevalence of a second distal root.
Special Care in Dentistry, 2021
AimsTo investigate barriers experienced by clinicians treating individuals with special needs in ... more AimsTo investigate barriers experienced by clinicians treating individuals with special needs in the Australian public dental system.Methods and resultsOral health professionals working at primary care clinics in the public dental system were invited to participate in semi‐structured interviews or focus groups to discuss the challenges they faced in managing patients with special needs. Qualitative methods, employing inductive thematic analysis, revealed two primary barriers: 1. clinicians lacked confidence in their ability to treat patients with special needs because of insufficient training and experience, and difficulties obtaining information about their patients, and 2. barriers within the public dental system, including inadequate funding, equipment and facilities, and productivity pressures prevented clinicians from being able to provide the care patients required. The priority and understanding of the oral health for these individuals within the public dental system and wide...
Journal of law and medicine, 2016
The aim of this study was to determine the factors affecting the quantity and quality of informat... more The aim of this study was to determine the factors affecting the quantity and quality of information recalled by patients following endodontic consultations and their effect on anxiety. New patients attending the Royal Dental Hospital of Melbourne and University of Melbourne Dental Clinic were asked to complete a questionnaire assessing the amount of information retained following their consultation, determining a patient's threshold for information disclosure and the effect of the consultation on patient anxiety. Only 9% of patients recalled more than two complications. Males (P = 0.02), patients older than 65 years (P < 0.001), and patients with education limited to high school (P < 0.001) recalled significantly less information. Most respondents (71.3%) wanted information about complications with a prevalence of less than 1%. Only 11 patients (8%) developed more anxiety as a consequence of the consultation. Patients had overall poor recall of complications following end...
Journal of Endodontics, 2021
INTRODUCTION The presence of multiple root canals is an important morphological aspect of mandibu... more INTRODUCTION The presence of multiple root canals is an important morphological aspect of mandibular premolars. This study aimed to perform a worldwide analysis on the prevalence of a lingual canal in mandibular premolars and evaluate its influence on patients' demographics of 23 countries using CBCT images. METHODS Observers from 23 countries were instructed to evaluate CBCT images of 300 first and 300 second premolars (13,800 teeth) regarding the presence of a lingual canal, canal configuration, and data related to patients' ethnicity, age and gender, following a standardized screening methodology. Intra- and inter-rater evaluations were performed using Cohen's kappa test and intraclass correlation coefficient (ICC). Proportion and odds ratio forest plots were calculated in order to compare groups. Statistical significance was set at 5%. RESULTS Both kappa and ICC values were above 0.60 and percentage of agreement was 94.9% (first premolar) and 97.8% (second premolar). A significant statistical difference was observed between the worldwide proportion of a lingual canal in mandibular first (23.8%; 12.0-32.7%) and second (5.3%; 1.0%-15.3%) premolars (P < .05). Asians and patients over 60 years-old were associated with the lowest proportions of a lingual canal (P < .05), while Africans and younger groups with the highest (P < .05). Prevalence of a lingual canal in males (27.9%) was higher than females (20.0%) for the first premolar only (P < .05). Males were associated with 1.533 and 1.597 higher odds of presenting a lingual root canal in the first and second premolars, respectively. CONCLUSIONS The worldwide proportion of a lingual root canal was 23.6% and 5.3% for first and second premolars, respectively. Ethnicity, geographic region, age and gender had influence in the outcomes.
Odontology, 2020
To investigate the effect of benzalkonium chloride (BAC) addition to ethylenediaminetetraacetic a... more To investigate the effect of benzalkonium chloride (BAC) addition to ethylenediaminetetraacetic acid (EDTA) on transforming growth factor-β1 (TGF-β1) release, as well as attachment and proliferation of dental pulp stem cells (DPSCs) on dentin. A total of standard 268 human dentin disks were prepared and immersed in 1.5% sodium hypochlorite (NaOCl) for 5 min. The disks were rinsed with distilled water and randomly divided into seven groups. In control group, the disks received no further treatment. The remaining disks were immersed in following solutions: 17% EDTA or 17% EDTA + 0.008% BAC for 1, 5 or 10 min and rinsed with distilled water. DPSCs were seeded in part of the disks since the TGF-β1 release assay was performed with disks with and without cells. The attachment and proliferation of DPSCs on dentin disks were analyzed using lactate dehydrogenase activity and WST-1 assays, respectively. The cell morphology was observed by scanning electron microscopy. The release of TGF-β1 was quantified using ELISA. Data were analyzed using three-and two-way analysis of variance with Bonferroni corrections. Both EDTA solutions increased the attachment and proliferation of DPSCs (p < .05) while there was no significant difference between them (p > .05). The exposure time of both EDTA solutions had no influence on cell attachment, proliferation and TGF-β1 release (p > .05). There was no significant difference in TGF-β1 release between the control and experimental groups (p > .05). The amount of released TGF-β1 from dentin disks was similar whether or not they were seeded with cells (p > .05). Dentin treatment with either of the EDTA solutions had no effect on the amount of TGF-β1 release while both EDTA solutions improved cell attachment and proliferation on dentin surface regardless of exposure time.
Journal of Dentistry, 2020
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Journal of Endodontics, 2018
Introduction: There is limited literature on the impact of testing variables on the push‐out bond... more Introduction: There is limited literature on the impact of testing variables on the push‐out bond test (POBT). This review identified designs of the POBT used in the endodontic literature and aimed to determine which experimental variables may influence the push‐out bond strength (POBS). Methods: A systematic review based on PRISMA guidelines was performed by searching the PubMed, SCOPUS, and Cochrane library databases using terms including push‐out and dislocation resistance and descriptions of endodontic materials. Test variables assessed included method of root preparation, timing of sectioning compared with filling, thickness, diameter and taper of sections, and plunger size and velocity. The POBS of 3 common materials (gutta‐percha and AH Plus, mineral trioxide aggregate, and Biodentine) were collected from investigations, and a comparison was attempted. Results: One hundred thirty‐three studies assessed the POBS of root‐filling materials, 68 assessed root repair cements/root‐end filling materials, and 16 assessed orifice barrier materials other than mineral trioxide aggregate. There was significant variation in all of the assessed variables, resulting in a large range of reported values for the POBS of the various materials. Because of this heterogeneity in study design, no further statistical analysis of the impact of the test variables on POBS was possible. Conclusions: There was considerable variation in the POBT design used in endodontic research. Greater standardization is required for future research as well as accurate reporting for all test variables to assess the impact of specific design variables on POBS. HIGHLIGHTSPOBT in endodontic research predicts the clinical behavior of endodontic materials.Great variability in POBT criteria compromises interpretation and clinical extrapolation.Greater standardization of the variables related to this test is required.
Journal of Endodontics, 2017
Introduction: This case report presents the treatment of a 16-year-old boy with a maxillary later... more Introduction: This case report presents the treatment of a 16-year-old boy with a maxillary lateral incisor (tooth #10) presenting with Oehlers type II dens invaginatus and diagnosed with previously initiated therapy and asymptomatic apical periodontitis. Methods: A regenerative endodontic procedure (REP) was performed for the tooth but complicated by apically displaced mineral trioxide aggregate (MTA). Clinical and radiographic examination was undertaken yearly, and a cone-beam computed tomography scan was taken to investigate further the formation of hard tissues within the root canal. Subsequently, tooth #10 was re-accessed and then rootfilled with MTA. Results: There was complete periapical healing, thickening of the dentinal root walls, and completed apex formation 3 years after REP. Hard tissue formation was noted within the root canal, on the root canal wall, and the root apex through clinical and radiographic examination. Less hard tissue formation was noted on the labial root canal wall where the displaced MTA was located, which was identified on the conebeam computed tomography scan. Conclusions: This report demonstrates that REP can potentially provide excellent treatment outcomes for structurally compromised teeth. REP should be considered as a first-line treatment before proceeding with a root filling when root development is incomplete, but attention to technical detail is essential.
Australian Dental Journal, 2016
S7 Assessment and validation of a diagnostic scale, oral care protocol, the prevention and treatm... more S7 Assessment and validation of a diagnostic scale, oral care protocol, the prevention and treatment of oral mucositis in a paediatric population receiving cancer therapy
Journal of Endodontics, 2017
Introduction: Internal bleaching of discolored teeth uses sodium perborate reacting with water to... more Introduction: Internal bleaching of discolored teeth uses sodium perborate reacting with water to form the active agent, hydrogen peroxide (H 2 O 2). Sodium perborate is replaced at varying time intervals depending on clinician preference and until esthetically acceptable results are achieved, but this is done without scientific basis. This study measured the depletion rate of hydrogen peroxide from sodium perborate as a bleaching agent. Methods: Two sodium perborate bleaching products (Odontobleach [Australian Dental Manufacturing, Kenmore Hills, Queensland, Australia] and Endosure Perborate Micro [Dentalife, Ringwood, Victoria, Australia]) and distilled deionized water mixtures at ratios of 25 mg/mL, 50 mg/mL, and 100 mg/mL were placed into sealed microtubes and incubated at 37 C. H 2 O 2 concentrations were measured at 23 time points over 4 weeks. Quantification of H 2 O 2 concentrations was obtained using a ferrothiocyanate oxidation reduction reaction followed by spectrophotometry readings. Results: The H 2 O 2 concentration rapidly peaked within 27 hours and reached a plateau by about 3 days (75 hours). Low levels of H 2 O 2 were evident beyond 3 days and for at least 28 days. No significant differences were found between the 2 sodium perborate products. There was also no significant difference in the depletion rate between the different ratios. Conclusions: Based on the chemistry of H 2 O 2 depletion, the minimum replacement interval for the bleaching agent is 3 days. Frequent replacements of the perborate clinically may be unnecessary because of the continued presence of low H 2 O 2 levels for at least 28 days. Although these data cannot be extrapolated to the clinical situation, they set a baseline for further studies to address the many clinical variables influencing internal bleaching.
Australian dental journal, 2015
Patients are living longer and the rate of edentulism is decreasing. Endodontic treatment is an e... more Patients are living longer and the rate of edentulism is decreasing. Endodontic treatment is an essential part of maintaining the health and well-being of the elderly. Retention of natural teeth improves the quality of life and the overall health and longevity of ageing patients. Also, teeth that might be otherwise extracted may be strategically valuable to retain a prosthesis, and elderly patients are more likely to have medical complications that may prevent dental extractions from being safely performed. The technical goals of endodontic treatment in the elderly are the same as those for younger patients. However, the pulpo-dentinal complex undergoes calcific changes over time, which may pose challenges for the clinician. The purposes of this review are to discuss age changes in the pulp and the challenges posed by diagnosing, treatment planning and treating the elderly endodontic patient.
Australian Dental Journal, 2015
This study investigated the frequency, patterns and causes of dental trauma in patients seeking e... more This study investigated the frequency, patterns and causes of dental trauma in patients seeking emergency treatment at a dental hospital, and evaluated the impact of an electronic structured injury history form to collect key information. A retrospective audit was undertaken of all emergency presentations at the Royal Dental Hospital of Melbourne from 2009 to 2012. Dental trauma and injury surveillance data were collected and evaluated with reference to the criteria of the Victorian Emergency Minimum Dataset. Statistical analysis included chi-squared and Fisher's exact tests. A total of 88 610 new emergency courses of care were created, with 3642 (4.1%) identified as new dental trauma cases in 3574 patients. A total of 6001 teeth were injured with a mean of 1.7 teeth per patient (range: 1-8 teeth). The improvement of injury surveillance information collected using the electronic form compared with the paper form was statistically significant (p < 0.001). The dental trauma findings of this study are consistent with other studies regarding age, gender, location, cause and injury type. This study also confirmed the benefits of electronic collection of dental injury surveillance data that can assist policy planners and health service providers in designing and delivering effective dental injury prevention and management services.
International endodontic journal, Jan 11, 2014
To evaluate the effect of tooth radiographic features on root canal retreatment strategies used b... more To evaluate the effect of tooth radiographic features on root canal retreatment strategies used by general dental practitioners and dental specialists in Australia. A descriptive survey study comprising a web-based questionnaire was sent to general dental practitioners and specialists. The questionnaire diagrammatically represented six different clinical scenarios with variables including type of coronal restoration, quality of root filling and the size and presence of a periapical radiolucency. Treatment options included no treatment, orthograde retreatment, periapical surgery and replacement with an implant. For each of the six scenarios, the participant was asked to select a minimum size cut-off point where treatment would be initiated and also indicate the preferred treatment option. A total of 639 questionnaires were submitted online. In teeth without a cast core restoration, the quality of root filling influenced the selection of no treatment as an option (P < 0.001). The p...
Journal of Endodontics, 2013
Introduction: This study assessed and characterized discoloration when white MTA (wMTA) was place... more Introduction: This study assessed and characterized discoloration when white MTA (wMTA) was placed in the coronal aspect of the root canal ex vivo and the influence of red blood cells on this discoloration. Methods: Canals were prepared from the apical aspect and restored with either wMTA + saline (n = 18), wMTA + blood (n = 18), or controls (n = 4 + 4) (blood or saline alone). Color was assessed according to the CIE L*a*b* color space using standardized digital photographs at 3 time points: baseline, day 1, and day 35. Statistical analysis was performed by using 1-way analysis of variance and a 2-sample t test with P < .05. Results: All teeth discolored when restored with wMTA, which was most prominent in the cervical third of the crown. The presence of blood within the canal adjacent to the setting wMTA exacerbated the discoloration (P = .03). Conclusions: wMTA induces the gray discoloration of the tooth crown, and the effect is compounded in the presence of blood.
Dental research journal, 2023
Australian Endodontic Journal
International Endodontic Journal
Observational studies are non‐interventional studies that establish the prevalence and incidence ... more Observational studies are non‐interventional studies that establish the prevalence and incidence of conditions or diseases in populations or analyse the relationship between health status and other variables. They also facilitate the development of specific research questions for future randomized trials or to answer important scientific questions when trials are not possible to carry out. This article outlines the previously documented consensus‐based approach by which the Preferred Reporting items for Observational studies in Endodontics (PROBE) 2023 guidelines were developed. A steering committee of nine members was formed, including the project leaders (PD, VN). The steering committee developed an initial checklist by combining and adapting items from the STrengthening the Reporting of Observational studies in Epidemiology (STROBE) checklist and the Clinical and Laboratory Images in Publications (CLIP) principles, as well as adding several new items specifically for the specialt...
Journal of the Mechanical Behavior of Biomedical Materials
The objectives of this study were to evaluate 4 aspects of ion-leaching restorative materials (IL... more The objectives of this study were to evaluate 4 aspects of ion-leaching restorative materials (ILMs): 4-point bending flexural strength (4 PB-FS) and relative mechanical properties; biaxial flexural strength (B-FS) in relation to 4 PB-FS; porosity; and surface morphology. Eleven ILMs were used for the 4-point bending test. Bar-shaped (n = 15) samples were fabricated, stored in distilled water for 7 days. Then 4 PB-FS and the other mechanical properties were determined. Five ILMs were selected for the B-FS test using disk specimens (n = 15). The correlation between 4 PB-FS and B-FS was addressed. After the 4 PB test, 5 randomised fragments from each material were used to make 0.5 mm-thick sections for light microscopy to investigate the degree of porosity using reflected and transmitted lights. Eight ILMs were selected for quantitative analysis of the fractional % pore volume (PV%) due to their relative pore prominence using ImageJ software. One-way ANOVA/Dunnett's T3 was used to test for significance. Resin-based ILMs (RB-ILMs) were ranked first (p < 0.05) for 4 PB-FS values (53.3-110.2 MPa) followed by resin-modified glass-ionomer cements (RMGICs; 30.9-44.3 MPa) and high-viscosity glass-ionomer cements (HVGICs; 12.9-19.6 MPa), respectively. 'Flexural modulus' (4 PB-E) and 'flexural toughness' (4 PB-T) of ILMs varied even though similar 4 PB-FS values were observed. There was a positive correlation (p < 0.001) between 4PB-FS and B-FS (R2 = 0.992) with B-FS>4 PB-FS. There was no correlation between PV% and 4 PB-FS. In summary, material type played a major role in 4 PB-FS outcomes, whereas PV% seemed to have a minor effect when evaluating each material group of ILMs. Brittleness/ductility of ILMs was observed when determining 4 PB-E and 4 PB-T relative to 4 PB-FS. When selecting materials for posterior load-bearing dental restorations in high-caries risk patients, RB-ILMs or RMGICs would be more appropriate due to their superior flexural properties compared with recently introduced HVGICs. The decision for each situation will also be dependent on further evidence of the ion-leaching capacity.
Australian Dental Journal
BackgroundPeople with special health care needs continue to have difficulties accessing regular d... more BackgroundPeople with special health care needs continue to have difficulties accessing regular dental care partly due to oral health professionals feeling they lack the knowledge and experience to provide treatment to these individuals.MethodsQualitative interviews and focus groups provided an insight into the types and nature of supports that oral health professionals working in the Australian public dental system desired and felt may improve their willingness and/or ability to treat patients with special needs.ResultsAlthough participants did not identify one group of patients with special needs that were more difficult to treat, they did report a feeling of being unsupported. Clinicians felt that improved training and access to ongoing education in Special Needs Dentistry, opportunities for greater support from specialists or other health professionals, either through networking or other media such as telehealth, and fostering a more supportive clinical environment, particularly...
Australian Dental Journal, 2022
BACKGROUND Canalis sinuosus (CS) and its relationship with adjacent teeth is relevant for surgery... more BACKGROUND Canalis sinuosus (CS) and its relationship with adjacent teeth is relevant for surgery in the anterior maxilla. Therefore, the aim of this study was to report the prevalence, characteristics, and variations of CS. METHODS Cone beam computed tomography (CBCT) scans of the anterior maxilla of 201 patients were reviewed. CS and the adjacent teeth were analysed by age, sex, and scan resolution, using analysis of variance, chi-squared and Fisher's exact tests. The widest and narrowest diameters of CS, and distance to tooth apex (DTA), were compared by quadrant, closest tooth, and location, and the associations were examined statistically with P < 0.05. RESULTS In the 201 scans, 412 CS were identified in 198 patients associated with 395 different teeth. Mean widest diameter was 1.08 ± 0.39 mm (range: 0.42-2.60 mm), while the narrowest diameter was 0.71 ± 0.26 mm (range: 0.25-1.59 mm), and mean DTA of 2.16 ±1.25 mm (range: 0-6.22 mm). CS detection was significantly lower with CBCT taken at resolution size of 0.250 voxels (P = 0.02). CONCLUSIONS CS was very common in the anterior maxilla. Clinicians would be well advised to identify this anatomical structure using CBCT before undertaking any surgery in the anterior maxilla. © 2022 Australian Dental Association.
Journal of Endodontics, 2021
INTRODUCTION This study assessed the prevalence of radix entomolaris and two canals at the distal... more INTRODUCTION This study assessed the prevalence of radix entomolaris and two canals at the distal aspect of mandibular first molars amongst different geographic regions by means of cone-beam computed tomography (CBCT). METHODS Pre-calibrated observers from 23 worldwide geographic locations followed a standardized screening protocol to assess 5,750 CBCT images of mandibular first molars (250 per region) gathering demographic data and recording the presence of radix entomolaris and a second canal at the distal aspect of teeth. Intra- and inter-rater reliability tests were conducted and comparisons amongst groups were performed using proportions and odds ratio forest plots. Significance level was set at 5%. RESULTS Results of intra- and inter-rater tests were above 0.79. The prevalence of radix entomolaris varied from 0.9% in Venezuela (0%-1.9%, CI 95%) to 22.4% in China (17.2%-27.6%, CI 95%). Regarding the proportion of a second distal canal, it ranged from 16.4% in Venezuela (11.8%-21.0%, CI 95%) to 60.0% in Egypt (53.9%-66.1%, CI 95%). East Asia subgroup was associated with significantly higher prevalence of an extra distolingual root, while America subgroup, American native ethnic group and elderly patients were linked to significantly lower percentages of a second canal at the distal aspect of teeth. No significant differences were noted between male or female patients. CONCLUSIONS The overall worldwide prevalence of radix entomolaris and a second canal at the distal aspect of the mandibular first molar were 5.6% and 36.9%, respectively. East Asia geographic region and Asian ethnic group had higher prevalence of a second distal root.
Special Care in Dentistry, 2021
AimsTo investigate barriers experienced by clinicians treating individuals with special needs in ... more AimsTo investigate barriers experienced by clinicians treating individuals with special needs in the Australian public dental system.Methods and resultsOral health professionals working at primary care clinics in the public dental system were invited to participate in semi‐structured interviews or focus groups to discuss the challenges they faced in managing patients with special needs. Qualitative methods, employing inductive thematic analysis, revealed two primary barriers: 1. clinicians lacked confidence in their ability to treat patients with special needs because of insufficient training and experience, and difficulties obtaining information about their patients, and 2. barriers within the public dental system, including inadequate funding, equipment and facilities, and productivity pressures prevented clinicians from being able to provide the care patients required. The priority and understanding of the oral health for these individuals within the public dental system and wide...
Journal of law and medicine, 2016
The aim of this study was to determine the factors affecting the quantity and quality of informat... more The aim of this study was to determine the factors affecting the quantity and quality of information recalled by patients following endodontic consultations and their effect on anxiety. New patients attending the Royal Dental Hospital of Melbourne and University of Melbourne Dental Clinic were asked to complete a questionnaire assessing the amount of information retained following their consultation, determining a patient's threshold for information disclosure and the effect of the consultation on patient anxiety. Only 9% of patients recalled more than two complications. Males (P = 0.02), patients older than 65 years (P < 0.001), and patients with education limited to high school (P < 0.001) recalled significantly less information. Most respondents (71.3%) wanted information about complications with a prevalence of less than 1%. Only 11 patients (8%) developed more anxiety as a consequence of the consultation. Patients had overall poor recall of complications following end...
Journal of Endodontics, 2021
INTRODUCTION The presence of multiple root canals is an important morphological aspect of mandibu... more INTRODUCTION The presence of multiple root canals is an important morphological aspect of mandibular premolars. This study aimed to perform a worldwide analysis on the prevalence of a lingual canal in mandibular premolars and evaluate its influence on patients' demographics of 23 countries using CBCT images. METHODS Observers from 23 countries were instructed to evaluate CBCT images of 300 first and 300 second premolars (13,800 teeth) regarding the presence of a lingual canal, canal configuration, and data related to patients' ethnicity, age and gender, following a standardized screening methodology. Intra- and inter-rater evaluations were performed using Cohen's kappa test and intraclass correlation coefficient (ICC). Proportion and odds ratio forest plots were calculated in order to compare groups. Statistical significance was set at 5%. RESULTS Both kappa and ICC values were above 0.60 and percentage of agreement was 94.9% (first premolar) and 97.8% (second premolar). A significant statistical difference was observed between the worldwide proportion of a lingual canal in mandibular first (23.8%; 12.0-32.7%) and second (5.3%; 1.0%-15.3%) premolars (P < .05). Asians and patients over 60 years-old were associated with the lowest proportions of a lingual canal (P < .05), while Africans and younger groups with the highest (P < .05). Prevalence of a lingual canal in males (27.9%) was higher than females (20.0%) for the first premolar only (P < .05). Males were associated with 1.533 and 1.597 higher odds of presenting a lingual root canal in the first and second premolars, respectively. CONCLUSIONS The worldwide proportion of a lingual root canal was 23.6% and 5.3% for first and second premolars, respectively. Ethnicity, geographic region, age and gender had influence in the outcomes.
Odontology, 2020
To investigate the effect of benzalkonium chloride (BAC) addition to ethylenediaminetetraacetic a... more To investigate the effect of benzalkonium chloride (BAC) addition to ethylenediaminetetraacetic acid (EDTA) on transforming growth factor-β1 (TGF-β1) release, as well as attachment and proliferation of dental pulp stem cells (DPSCs) on dentin. A total of standard 268 human dentin disks were prepared and immersed in 1.5% sodium hypochlorite (NaOCl) for 5 min. The disks were rinsed with distilled water and randomly divided into seven groups. In control group, the disks received no further treatment. The remaining disks were immersed in following solutions: 17% EDTA or 17% EDTA + 0.008% BAC for 1, 5 or 10 min and rinsed with distilled water. DPSCs were seeded in part of the disks since the TGF-β1 release assay was performed with disks with and without cells. The attachment and proliferation of DPSCs on dentin disks were analyzed using lactate dehydrogenase activity and WST-1 assays, respectively. The cell morphology was observed by scanning electron microscopy. The release of TGF-β1 was quantified using ELISA. Data were analyzed using three-and two-way analysis of variance with Bonferroni corrections. Both EDTA solutions increased the attachment and proliferation of DPSCs (p < .05) while there was no significant difference between them (p > .05). The exposure time of both EDTA solutions had no influence on cell attachment, proliferation and TGF-β1 release (p > .05). There was no significant difference in TGF-β1 release between the control and experimental groups (p > .05). The amount of released TGF-β1 from dentin disks was similar whether or not they were seeded with cells (p > .05). Dentin treatment with either of the EDTA solutions had no effect on the amount of TGF-β1 release while both EDTA solutions improved cell attachment and proliferation on dentin surface regardless of exposure time.
Journal of Dentistry, 2020
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Journal of Endodontics, 2018
Introduction: There is limited literature on the impact of testing variables on the push‐out bond... more Introduction: There is limited literature on the impact of testing variables on the push‐out bond test (POBT). This review identified designs of the POBT used in the endodontic literature and aimed to determine which experimental variables may influence the push‐out bond strength (POBS). Methods: A systematic review based on PRISMA guidelines was performed by searching the PubMed, SCOPUS, and Cochrane library databases using terms including push‐out and dislocation resistance and descriptions of endodontic materials. Test variables assessed included method of root preparation, timing of sectioning compared with filling, thickness, diameter and taper of sections, and plunger size and velocity. The POBS of 3 common materials (gutta‐percha and AH Plus, mineral trioxide aggregate, and Biodentine) were collected from investigations, and a comparison was attempted. Results: One hundred thirty‐three studies assessed the POBS of root‐filling materials, 68 assessed root repair cements/root‐end filling materials, and 16 assessed orifice barrier materials other than mineral trioxide aggregate. There was significant variation in all of the assessed variables, resulting in a large range of reported values for the POBS of the various materials. Because of this heterogeneity in study design, no further statistical analysis of the impact of the test variables on POBS was possible. Conclusions: There was considerable variation in the POBT design used in endodontic research. Greater standardization is required for future research as well as accurate reporting for all test variables to assess the impact of specific design variables on POBS. HIGHLIGHTSPOBT in endodontic research predicts the clinical behavior of endodontic materials.Great variability in POBT criteria compromises interpretation and clinical extrapolation.Greater standardization of the variables related to this test is required.
Journal of Endodontics, 2017
Introduction: This case report presents the treatment of a 16-year-old boy with a maxillary later... more Introduction: This case report presents the treatment of a 16-year-old boy with a maxillary lateral incisor (tooth #10) presenting with Oehlers type II dens invaginatus and diagnosed with previously initiated therapy and asymptomatic apical periodontitis. Methods: A regenerative endodontic procedure (REP) was performed for the tooth but complicated by apically displaced mineral trioxide aggregate (MTA). Clinical and radiographic examination was undertaken yearly, and a cone-beam computed tomography scan was taken to investigate further the formation of hard tissues within the root canal. Subsequently, tooth #10 was re-accessed and then rootfilled with MTA. Results: There was complete periapical healing, thickening of the dentinal root walls, and completed apex formation 3 years after REP. Hard tissue formation was noted within the root canal, on the root canal wall, and the root apex through clinical and radiographic examination. Less hard tissue formation was noted on the labial root canal wall where the displaced MTA was located, which was identified on the conebeam computed tomography scan. Conclusions: This report demonstrates that REP can potentially provide excellent treatment outcomes for structurally compromised teeth. REP should be considered as a first-line treatment before proceeding with a root filling when root development is incomplete, but attention to technical detail is essential.
Australian Dental Journal, 2016
S7 Assessment and validation of a diagnostic scale, oral care protocol, the prevention and treatm... more S7 Assessment and validation of a diagnostic scale, oral care protocol, the prevention and treatment of oral mucositis in a paediatric population receiving cancer therapy
Journal of Endodontics, 2017
Introduction: Internal bleaching of discolored teeth uses sodium perborate reacting with water to... more Introduction: Internal bleaching of discolored teeth uses sodium perborate reacting with water to form the active agent, hydrogen peroxide (H 2 O 2). Sodium perborate is replaced at varying time intervals depending on clinician preference and until esthetically acceptable results are achieved, but this is done without scientific basis. This study measured the depletion rate of hydrogen peroxide from sodium perborate as a bleaching agent. Methods: Two sodium perborate bleaching products (Odontobleach [Australian Dental Manufacturing, Kenmore Hills, Queensland, Australia] and Endosure Perborate Micro [Dentalife, Ringwood, Victoria, Australia]) and distilled deionized water mixtures at ratios of 25 mg/mL, 50 mg/mL, and 100 mg/mL were placed into sealed microtubes and incubated at 37 C. H 2 O 2 concentrations were measured at 23 time points over 4 weeks. Quantification of H 2 O 2 concentrations was obtained using a ferrothiocyanate oxidation reduction reaction followed by spectrophotometry readings. Results: The H 2 O 2 concentration rapidly peaked within 27 hours and reached a plateau by about 3 days (75 hours). Low levels of H 2 O 2 were evident beyond 3 days and for at least 28 days. No significant differences were found between the 2 sodium perborate products. There was also no significant difference in the depletion rate between the different ratios. Conclusions: Based on the chemistry of H 2 O 2 depletion, the minimum replacement interval for the bleaching agent is 3 days. Frequent replacements of the perborate clinically may be unnecessary because of the continued presence of low H 2 O 2 levels for at least 28 days. Although these data cannot be extrapolated to the clinical situation, they set a baseline for further studies to address the many clinical variables influencing internal bleaching.
Australian dental journal, 2015
Patients are living longer and the rate of edentulism is decreasing. Endodontic treatment is an e... more Patients are living longer and the rate of edentulism is decreasing. Endodontic treatment is an essential part of maintaining the health and well-being of the elderly. Retention of natural teeth improves the quality of life and the overall health and longevity of ageing patients. Also, teeth that might be otherwise extracted may be strategically valuable to retain a prosthesis, and elderly patients are more likely to have medical complications that may prevent dental extractions from being safely performed. The technical goals of endodontic treatment in the elderly are the same as those for younger patients. However, the pulpo-dentinal complex undergoes calcific changes over time, which may pose challenges for the clinician. The purposes of this review are to discuss age changes in the pulp and the challenges posed by diagnosing, treatment planning and treating the elderly endodontic patient.
Australian Dental Journal, 2015
This study investigated the frequency, patterns and causes of dental trauma in patients seeking e... more This study investigated the frequency, patterns and causes of dental trauma in patients seeking emergency treatment at a dental hospital, and evaluated the impact of an electronic structured injury history form to collect key information. A retrospective audit was undertaken of all emergency presentations at the Royal Dental Hospital of Melbourne from 2009 to 2012. Dental trauma and injury surveillance data were collected and evaluated with reference to the criteria of the Victorian Emergency Minimum Dataset. Statistical analysis included chi-squared and Fisher's exact tests. A total of 88 610 new emergency courses of care were created, with 3642 (4.1%) identified as new dental trauma cases in 3574 patients. A total of 6001 teeth were injured with a mean of 1.7 teeth per patient (range: 1-8 teeth). The improvement of injury surveillance information collected using the electronic form compared with the paper form was statistically significant (p < 0.001). The dental trauma findings of this study are consistent with other studies regarding age, gender, location, cause and injury type. This study also confirmed the benefits of electronic collection of dental injury surveillance data that can assist policy planners and health service providers in designing and delivering effective dental injury prevention and management services.
International endodontic journal, Jan 11, 2014
To evaluate the effect of tooth radiographic features on root canal retreatment strategies used b... more To evaluate the effect of tooth radiographic features on root canal retreatment strategies used by general dental practitioners and dental specialists in Australia. A descriptive survey study comprising a web-based questionnaire was sent to general dental practitioners and specialists. The questionnaire diagrammatically represented six different clinical scenarios with variables including type of coronal restoration, quality of root filling and the size and presence of a periapical radiolucency. Treatment options included no treatment, orthograde retreatment, periapical surgery and replacement with an implant. For each of the six scenarios, the participant was asked to select a minimum size cut-off point where treatment would be initiated and also indicate the preferred treatment option. A total of 639 questionnaires were submitted online. In teeth without a cast core restoration, the quality of root filling influenced the selection of no treatment as an option (P < 0.001). The p...
Journal of Endodontics, 2013
Introduction: This study assessed and characterized discoloration when white MTA (wMTA) was place... more Introduction: This study assessed and characterized discoloration when white MTA (wMTA) was placed in the coronal aspect of the root canal ex vivo and the influence of red blood cells on this discoloration. Methods: Canals were prepared from the apical aspect and restored with either wMTA + saline (n = 18), wMTA + blood (n = 18), or controls (n = 4 + 4) (blood or saline alone). Color was assessed according to the CIE L*a*b* color space using standardized digital photographs at 3 time points: baseline, day 1, and day 35. Statistical analysis was performed by using 1-way analysis of variance and a 2-sample t test with P < .05. Results: All teeth discolored when restored with wMTA, which was most prominent in the cervical third of the crown. The presence of blood within the canal adjacent to the setting wMTA exacerbated the discoloration (P = .03). Conclusions: wMTA induces the gray discoloration of the tooth crown, and the effect is compounded in the presence of blood.