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Long-term survival of 57 premolars consecutively transplanted to premolar sites

Jonsson, Teitur; Jonsdottir, Hafdis B; Aspelund, Thor; Sigurdsson, Asgeir; Sigurdsson, Thorarinn J
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.
PMID: 39093250
ISSN: 1097-6752
CID: 5688622

Efficacy of Different Irrigation Needles and Ultrasonic Activation on Calcium Hydroxide Removal: A Micro-CT Study Using 3D-Printed Endodontic Models

Yoo, Yeon-Jee; Kim, Jae-Hoon; Hwang, Jae-Joon; Sigurdsson, Asgeir; Kim, Hyeon-Cheol
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.
PMID: 39033800
ISSN: 1878-3554
CID: 5688612

Clinical and patient-level predictors of procedure and tooth survival after direct pulp capping

Gencerliler, Nihan; Terlizzi, Kelly; Gold, Heather T; Sigurdsson, Asgeir; Burns, Lorel E
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.
PMID: 38970608
ISSN: 1943-4723
CID: 5688602

Access to Care Considerations for the Endodontic Treatment of Immature Permanent Teeth: A National Survey of Pediatric Dentists and Endodontists

Burns, Lorel E; Gencerliler, Nihan; Ribitzki, Uliana; Yashpal, Shahen; Feldman, Lauren; Sigurdsson, Asgeir; Gold, Heather T
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.
PMID: 38796057
ISSN: 1878-3554
CID: 5663172

Effects of Side Flattening on Torsional and Cyclic Fracture Resistance of Nickel-Titanium File

Jeong, Hee-Yoon; Ha, Jung-Hong; Sigurdsson, Asgeir; Peters, Ove A; Kim, Hyeon-Cheol; Kwak, Sang Won
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.
PMID: 38642733
ISSN: 1878-3554
CID: 5671252

Effect of Different Heat Treatments and Surface Treatments on the Mechanical Properties of Nickel-Titanium Rotary Files

Hong, Jihye; Kwak, Sang Won; Ha, Jung Hong; Sigurdsson, Asgeir; Shen, Ya; Kim, Hyeon Cheol
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.
SCOPUS:85174967526
ISSN: 2075-4701
CID: 5615042

Apexification Outcomes in the United States: A Retrospective Cohort Study

Burns, Lorel E; Gencerliler, Nihan; Terlizzi, Kelly; Solis-Roman, Claudia; Sigurdsson, Asgeir; Gold, Heather T
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.
PMCID:10543604
PMID: 37517583
ISSN: 1878-3554
CID: 5599482

Effect of Periodic Changes in Rotation Speed on Torsional Stress and Screw-in Force by Alternative Rotation Technique

Ha, Jung-Hong; Jo, Hyo-Jin; Kwak, Sang Won; Sigurdsson, Asgeir; Kim, Hyeon-Cheol
INTRODUCTION/BACKGROUND:This study evaluated the effect of periodic changes in rotation speed on torsional stress and screw-in force using the dedicated alternative rotation technique (ART) motion of the EQ-M (Metabiomed, Cheongju, Korea) endodontic motor. METHODS:Two ART modes of the EQ-M motor in 2 alternative techniques (ART30 and ART50) and continuous rotation were compared using ProTaper Next X2 (Dentsply Sirona, Charlotte, NC) files and simulated resin blocks (n = 12 per group). ART30 and ART50 were operated by continuous rotation of 350 rpm for 360° and then rotated at 30% increased speed from the base speed for 180° and at 50% increased speed for 180°, respectively. Before the test, the simulated resin blocks were pre-enlarged using ProTaper Gold S1 and S2 (Dentsply Sirona) and fixed on a metal stage connected to the force- and torque-measuring unit. During shaping the simulated canal in an automatic up-and-down manner, the parameters of maximum torque, sum of torque, maximum screw-in force, and maximum apical force were measured. The data were statistically analyzed using 1-way analysis of variance and the Tukey post hoc comparison test at the 95% significance level. RESULTS:The ART30 and ART50 groups showed a lower maximum torque, sum of torques, screw-in force, and apical drive force than the continuous rotation group. There was no significant difference between the ART30 and ART50 groups (P > .05). When the screw-in force increased suddenly, the torque correspondently increased. CONCLUSIONS:Under the limitations of this study, the ART mode could reduce the torsional stress and apical forces of the screw-in during instrumentation in comparison with continuous rotation.
PMID: 36375648
ISSN: 1878-3554
CID: 5374392

Sinus Tract vs. Fistural There is a Difference

Weinberg, Mea A; Segelnick, Stuart L; Chu, Christine; Sigurdsson, Asgeir
Orignial
ISSN: 0028-7571
CID: 5545592

Epidemiological Evaluation of the Outcomes of Initial Root Canal Therapy in Permanent Teeth of a Publicly Insured Pediatric Population

Burns, Lorel E; Terlizzi, Kelly; Solis-Roman, Claudia; Wu, Yinxiang; Sigurdsson, Asgeir; Gold, Heather T
BACKGROUND:Previously published epidemiological outcome studies of root canal therapy (NSRCT) in the Unites States utilize data only from a single, private dental insurer for adult populations. AIM/OBJECTIVE:This study aimed to investigate outcomes of initial NSRCT, performed on permanent teeth, in a publicly insured pediatric population. DESIGN/METHODS:New York State Medicaid administrative claims were used to follow 77,741 endodontic procedures in 51,545 patients aged 6-18, from the time of initial NSRCT until occurrence of an untoward event (retreatment, apicoectomy, extraction). Initial treatment and untoward events were identified by Current Dental Terminology codes. Kaplan-Meier survival estimates were calculated at 1, 3, and 5 years. Hazard ratios for time to permanent restoration and restoration type were calculated using Cox proportional hazard models. RESULTS:Median follow-up time was 44 months [range:12-158 months]. Procedural, NSRCT, survival was 98% at 1 year, 93% at 3 years, and 88% at 5 years. Extraction was the most common untoward event. Teeth permanently restored with cuspal coverage had the most favorable treatment outcomes. CONCLUSIONS:Overall, 89% of teeth were retained and remained functional over a minimum follow-up time of 5 years. These results elucidate expected outcomes of NSRCT in permanent teeth for pediatric patients with public-payer dental benefits.
PMID: 35000244
ISSN: 1365-263x
CID: 5118252