Faculty Bibliography

INTRODUCTION/BACKGROUND:There is a lack of epidemiology studies on cemental tears. This study aimed to (i) investigate the prevalence of cemental tears among the patients referred to a Postgraduate Endodontic Clinic, (ii) classify the cases diagnosed with cemental tears, and (iii) assess factors associated with cemental tears. MATERIALS AND METHODS/METHODS:This retrospective, cross-sectional study included 445 cases/teeth recruited between 1 September 2019 and 31 March 2024 at a University Postgraduate Endodontic Clinic. Information was collated from the clinical records of case history, clinical findings and radiographic interpretations from periapical radiograph (PR) and cone beam computed tomography (CBCT) images. For each case/tooth, cemental tear/s were categorised as either absent or present, and those with cemental tear/s were further classified. Thirty potential factors were studied, including patient-, jaw-, tooth-, previous endodontic treatment and periodontal-related factors. Factors were individually tested using univariate analysis with Pearson chi-squared (exact) tests. Any significant factors identified were further subjected to multiple logistic regression analyses based on a forward stepwise regression model (p < 0.05). RESULTS:Cemental tear/s were found in 25 out of 445 cases/teeth, with a prevalence of 5.6%. Sensitivity and specificity of PR in detecting cemental tears were 0.6 and 1.0, respectively. Most cases/teeth detected were classified as Class 2 and 4 (n = 19, 76%) or Stage C and D (n = 19, 76%). Mean age of the subjects with cemental tears was 58.7 years, with comparable prevalence between males and females. Most cases (72%) with cemental tear/s had root canal treatment initiated or completed. Incisors, increased tooth mobility, severe crestal bone loss and adequate root filling quality were significantly associated with the higher prevalence of cemental tears (p < 0.05). CONCLUSION/CONCLUSIONS:Cemental tears should always be considered as a differential diagnosis in endodontic practice. Clinicians should be particularly vigilant for increased risks of cemental tears in incisors, mobile teeth, teeth exhibiting increased crestal bone loss and those with adequately filled root canals, as they may be misdiagnosed as periodontal-endodontic lesions. The use of CBCT is crucial for accurate diagnosis, guiding effective treatment planning and improving clinical outcomes in endodontic management.

BACKGROUND:Evidence suggests that pediatric patients requiring endodontic treatment in the permanent dentition are often a "missed population". AIM/OBJECTIVE:This study surveyed pediatric dentists and endodontists about the frequency with which they encounter pediatric patients requiring endodontic treatment, their training, practice patterns, and decision-making considerations for the treatment of immature permanent teeth. DESIGN/METHODS:analysis. The level of significance was set at 0.05. RESULTS:The response rate was 13.1% (n = 840). The frequency of clinicians encountering pediatric patients requiring endodontic treatment for permanent teeth did not differ significantly by specialty. Pediatric dentists and endodontists reported statistically significant differences in their practice patterns related to the performance of vital pulp therapy (p < 0.001) and procedures for necrotic immature permanent teeth (p < 0.001). Among specialists, apexification was more frequently performed than regenerative endodontic procedures (REPs) (p < 0.001). When asked to consider clinical and patient factors related to the treatment of necrotic immature permanent teeth, pediatric dentists most frequently responded that they were "unsure" of their preferred treatment. CONCLUSION/CONCLUSIONS:Standardized clinical knowledge and management of immature permanent teeth between specialties may improve interdisciplinary care for pediatric patients.

INTRODUCTION/BACKGROUND:This study aimed to evaluate the correlation between the fibrous area ratio and the number of cycles to failure (NCF) in terms of fatigue fracture resistance of NiTi rotary files. METHODS:ProTaper Universal (PTU) and ProTaper Gold (PTG) files of size F2 (25 mm) were tested to make cyclic fatigue fracture using a custom-made device simulating a 35° canal curvature (n = 24). Using the fractured fragments, scanning electron microscopy (SEM) was taken to analyze the fracture surfaces, focusing on fibrous areas on the cross-sections. Fibrous area ratios were calculated using ImageJ software, and NCF was determined by multiplying the time to fracture by rotational speed. Statistical analysis was performed to evaluate differences between groups and assess the correlation between fibrous area ratio and NCF (P < .05). RESULTS:SEM analysis revealed a higher fibrous area ratio in PTU files (P < .05). The correlation analysis indicated a weak relationship between fibrous area ratio and NCF in both groups. PTG files demonstrated significantly higher NCF compared to PTU files (P < .05). PTG group had a significantly lower fibrous area ratio than the PTU group (P < .05). CONCLUSION/CONCLUSIONS:While PTG files show improved cyclic fatigue resistance due to thermal processing, the fibrous area ratio is not a strong representing factor or predictor of NCF. Heat treatment influences the property of fracture resistance more significantly than propagation process of cyclic fatigue fracture.

INTRODUCTION/BACKGROUND:The objective of this study was to report the long-term outcome of autotransplantation of premolars to other premolar recipient sites. METHODS:The sample was limited to adolescents seeking orthodontic treatment, and all had 1 or 2 premolars transplanted to a recipient site in which a premolar was congenitally missing. The transplantations were performed between 1980 and 2008, comprising 29 premolars in 22 males and 28 premolars in 22 females. Systematic clinical and radiographic follow-up varied from 1 year to 36.8 years, with a mean observation time of 18.9 years and a median of 19.2 years. Of the 57 transplanted teeth, 52 were subjected to orthodontic forces. RESULTS:A total of 9 of 57 teeth (15.8%) were lost during the observation period, and 8 of 9 lost teeth had been functional for at least 9 years posttransplantation. Of the 48 surviving transplants, 6 did not meet the criteria for success, giving an overall success rate of 73.7%. Complications were diagnosed within 5 years from the transplantation in 4 of 57 teeth (7.0%) and later in 11 of 57 (19.3%). The Kaplan-Meier survival curve shows that the complication-free proportion of transplants decreased at a constant rate over the observation time. The average survival time, taking censoring into account during follow-up of 36.8 years, was estimated as 28.5 years. The complications in the 15 teeth were classified into 4 categories: periapical lesions (6 teeth), inflammatory resorption (5 teeth), abrupt fracture (2 teeth), and ankylosis (2 teeth). CONCLUSIONS:Overall, premolar transplants in all stages of root formation have high success and survival rates. Transplants with complications may survive temporarily and preserve critical arch space and alveolar bone. Transplants with normal healing may have latent weaknesses that can eventually affect long-term survival.

INTRODUCTION/BACKGROUND:from an endodontic model that duplicated a root canal configuration of a human natural tooth. METHODS:. Data were analyzed using two-way analysis of variance test (α = .05). RESULTS:than the conventional group regardless of the type of needle (P < .05). However, no significant difference was found among the needles in the PUI group. CONCLUSIONS:regardless of the type of irrigation needle.

BACKGROUND:Historical reports of unpredictable outcomes associated with vital pulpal therapies, particularly direct pulp capping (DPC), have contributed to clinicians' skepticism of the procedure. Contemporary reports highlight more predictable outcomes of vital pulpal therapies, inclusive of DPC. There is a dearth of reported patient-centered outcomes of these procedures. METHODS:Insurance claims were used in an observational, retrospective cohort study to evaluate outcomes of DPC performed on permanent teeth. Statistical analyses included Kaplan-Meier survival estimates and Cox proportional hazards regression. Log-rank tests were used to evaluate unadjusted differences in survival. Cox proportional hazard regression was used to evaluate the adjusted hazard of adverse event occurrence. RESULTS:The analytic cohort included 4,136 teeth from 3,716 patients. DPC procedures were identified in public-payer (85.5%) and private-payer (13.4%) insurance claims databases. After DPC, procedure survival rate was 83% and tooth survival rate was 93% during a mean follow-up time of 52 months. Molar tooth type, same-day permanent restoration placement, and amalgam restoration type were significant positive predictors of procedure (DPC) survival. Age was not a statistically significant predictor of procedure survival after controlling for tooth type, gender, time to restoration, and restoration type. Nonmolar tooth type and younger age were significant positive predictors of tooth survival after DPC. Failures were most likely to occur within the first year. CONCLUSIONS:DPC has favorable patient-centered outcomes and contributes to long-term tooth survival. PRACTICAL IMPLICATIONS/CONCLUSIONS:The favorable patient-centered outcomes of DPC bolster calls to consider cost-effectiveness and access to care for endodontic procedures.

INTRODUCTION/BACKGROUND:This study aimed to investigate access to care and financial considerations associated with the endodontic treatment of immature permanent teeth. METHODS:analysis and logistic regression. The level of significance was set to 0.05. RESULTS:The response rate was 13% (n=840). Respondent specialist groups were similar by age and years since specialty residency completion, but significantly different with regard to primary practice setting (e.g. private practice, Federally Qualified Health Center, hospital…), (p=0.001). The majority (91%) of respondents reported participation with dental insurance. Pediatric dentists (69%) were significantly more likely than endodontists (17%) to participate with public-payer dental insurance (p<0.001). The majority of respondents (82%) indicated that patients reported economic factors (time or money) as a barrier to accessing endodontic treatment. Pediatric dentists were significantly more likely to consider economic factors when treatment planning (p<0.001). Pediatric dentists were more likely than endodontists to have the opinion that endodontic procedures for treatment of necrotic immature permanent teeth should cost less than root canal therapy (apexification, p<0.001; regenerative endodontic procedures, p=0.002). Pediatric dentists (33%) reported encountering barriers when attempting to refer their patients to an endodontist. Inability to find an endodontist that participates with dental insurance was the most frequently cited barrier. CONCLUSIONS:Limited clinician participation with dental insurance and gaps in insurance coverage for endodontic procedures appear to contribute to access to care barriers for pediatric patients.

INTRODUCTION/BACKGROUND:The purpose of this study was to evaluate the effect of side flattening of cutting flutes on the cyclic resistance and torsional resistance of nickel-titanium files. METHODS:Both novel flattened Platinum V.EU (PL) and standard nonflattened CC Premium V.EU (CC) rotaries were tested. For cyclic fatigue tests, all the files were rotated in an artificial root canal with a curvature of 45° and a radius of 6.06 mm at 300 rpm (n = 15 in each group). The number of cycles to failure (NCF) was calculated. For torsional tests, the files were rotated at 2 rpm clockwise until fracture occurred. The maximum torque value at fracture was measured and the toughness and distortion angle were computed. Subsequently, 5 fragments were randomly selected in each experiment, the cross-section and longitudinal direction of the fragments were photographed using a scanning electron microscope. An unpaired t-test was performed at a significance level of 95%. RESULTS:There was a statistically significant difference in NCF between CC and PL (P < .05). CC showed higher NCF than PL. There was no statistically significant difference between CC and PL with regards to the parameters related to torsional resistance (distortion angle, ultimate strength, and toughness) (P > .05). CONCLUSION/CONCLUSIONS:Within the limitations of this study, side flattening of the file did not improve cyclic resistance or torsional resistance of the files. As side flattening may reduce a file's cyclic resistance, such files should be used with caution in clinical practice.

This study aimed to compare the fatigue resistance of files made from different heat treatment methods and surface treatment. Four prototype files were created through heat treatment and titanium coating surface treatment (AT, DT, ER, EN; named arbitrarily by the manufacturer) at different times and temperatures. Artificial canals with curvatures of 45- and 90-degree were used for the fatigue testing. The files were operated at the speed of 500 rpm at 37 °C, and the time until fracture incurred by a 4-mm dynamic pecking motion at a speed of 8 mm/s was measured, and the number of cycles to failure (NCF) was calculated by applying rotation speed and time. The length of the fractured fragment was measured. The fractured specimens were observed under the SEM to compare the characteristics of fatigue fracture patterns. Differential scanning calorimetry analysis was performed to estimate the phase transformation temperature. One-way ANOVA with Duncan"™s post-hoc comparison, the Kruskal"“Wallis test, and Mann"“Whitney U were applied to compare the fatigue resistance among the prototypes at a significance level of 95%. Regardless of the canal angle, the EN showed the highest fatigue resistance (p < 0.05). AT had the lowest NCF at the 90-degree canal (p < 0.05). ER had a higher NCF than the DT at 45 degrees (p < 0.05), but there was no difference at 90 degrees. DSC analysis revealed that the ER and EN groups exhibited two austenite peaks above 40 °C. In conclusion, the file that underwent a specific temperature heat treatment with titanium coating surface treatment showed the highest fatigue resistance.

INTRODUCTION/BACKGROUND:This epidemiological analysis used procedure codes from dental insurance claims data to identify apexification cases and evaluate survival at the tooth-level. METHODS:Dental insurance claims data from New York State (2006-2019) and Massachusetts (2013-2018) were used in an observational, retrospective cohort study to evaluate the provision and treatment outcomes of apexification. Statistical analyses included Kaplan-Meier survival estimates and Cox proportional hazards regression. Cox proportional hazard regression was used to evaluate the hazard of adverse event occurrence by age, gender, tooth type, placement of permanent restoration, and dental provider type. A sensitivity analysis evaluated potential bias in the survival estimates and adjusted hazard ratios (aHRs) due to differential loss to follow-up. Robust standard errors were used to account for potential dependence between teeth within an individual. RESULTS:The analytic cohort of 575 individuals included 632 teeth, with an average follow-up time of 64 months. The survival rates of apexification procedures were 95% at 1 year; 93% at 2 years; 90% at 3 years; and 86% at 5 years. Tooth retention following apexification was 98% at 1 year; 96% at 2 years; 95% at 3 years; and 90% at 5 years. Tooth type and subsequent placement of a permanent restoration were significant predictors of survival after apexification. CONCLUSIONS:The procedural and tooth survival outcomes of apexification were high and comparable to studies that analyzed clinical data on tooth survival following apexification.