Survival of endodontically treated teeth in public dental service in Northern Finland: a practise-based register study.

OBJECTIVE: The aim of this study was to explore the factors associated with the survival of root canal treated teeth in a practise-based study setting in a 5-year period. MATERIAL AND METHODS: This retrospective study used data from the electronic patient registration system of the public dental services of the City of Oulu, Finland. The inclusion criteria for this study were patients aged ≥ 20 years who had root canal treatment (RCT) that was initiated in 2014. One RCT per patient was included in the study. A total of 713 patients met the inclusion criteria. The outcome variable for this study was the extraction of the RCT tooth during the 5-year period. Explanatory variables included age, diagnosis, tooth type (incisive, canine, premolar, molar), RCT technique (manual, motorized), time from RCT initiation to final restoration and type of final restoration (composite, glass ionomer, fixed dental prosthesis). To evaluate the association between the outcome variable and explanatory variables, Cox regression analyses were performed. RESULTS: The overall survival rate was 91%. The middle-aged (40-59-years-old) and the oldest (60 and older) patients had a two-fold risk of extraction compared to younger (20-40-years-old) patients. Similarly, a short length of time from RCT initiation to final restoration (0-14 days) resulted in a nearly three times higher risk of extraction compared to a longer period (≥ 90 days). CONCLUSIONS: The 5-year survival rate of RCTs seems high. Extractions were more common among patients over 40 years of age and if the RCT was completed shortly after its initiation.

Further Interventions after Root Canal Treatment Are Most Common in Molars and Teeth Restored with Direct Restorations: A 10-11-Year Follow-Up of the Adult Swedish Population.

INTRODUCTION: The aims were to investigate 1) the frequency of nonsurgical retreatment, root-end surgery, extraction, and further restorative treatment during a follow-up of 10-11 years after root filling and compare the frequencies according to tooth group and type of coronal restoration and 2) the timing of nonsurgical retreatment, root-end surgery, and extraction. METHODS: Data were collected from the Swedish Social Insurance Agency's register. A search for treatment codes identified teeth root filled in 2009 and the type of coronal restoration (direct, indirect, and unspecified) registered within 6 months of root filling. The root-filled teeth were followed 10-11 years, and further interventions were recorded. Descriptive statistics and chi-square tests were used for statistical analysis. RESULTS: In 2009, root fillings were registered for 215,611 individuals/teeth. Nonsurgical retreatment, root-end surgery, and extraction were undertaken in 3.5%, 1.4%, and 20% teeth, respectively. The frequency of further interventions varied with respect to tooth group and type of coronal restoration, but only slightly for endodontic retreatments. Further interventions, except for root-end surgery, were registered more often for molars and directly restored teeth (P < .001). The majority of endodontic retreatments were undertaken within 4 years, while extractions were evenly distributed over 10-11 years. CONCLUSIONS: The frequency numbers of nonsurgical retreatment and root-end surgery were low, despite 1 in 5 root-filled teeth registered as extracted. Further interventions were most common in molars and directly restored teeth. Endodontic retreatments were performed more often during the first 4 years.

A comparison of radiographically determined periapical healing and tooth survival outcomes of root canal (re)treatment performed in two care pathways within the United Kingdom Armed Forces.

AIMS: To compare radiographic periapical healing and tooth survival outcomes of root canal (re)treatment performed within two care pathways (Routine Dental Care and Referred Treatment Pathway), in the United Kingdom Armed Forces (UKAF), and determine the effects of endodontic complexity on outcomes. METHODOLOGY: This retrospective cohort study included 1466 teeth in 1252 personnel who received root canal (re)treatment between 2015 and 2020. General Dental Practitioners treated 661 teeth (573 patients) (Routine cohort), whilst Dentists with a Special Interest treated 805 teeth (678 patients) (Referred cohort). The latter group were graduates of an MSc programme in Endodontics with 4-8 years of postgraduation experience. Case complexity was retrospectively determined for each tooth using the endodontic component of Restorative Index of Treatment Need (RIOTN) guidelines. Periapical healing was determined using loose radiographic criteria. The data were analysed using chi-square tests, univariate logistic regression and Cox proportional hazards models. RESULTS: A significantly (p < 0.0001) larger proportion of cases of low complexity had undergone root canal treatment within the Routine versus Referred cohort. The odds of periapical healing was significantly higher within the Referred versus Routine cohort, regardless of analyses using pooled (OR = 1.17; 95% CI: 1.11, 1.22) or moderate complexity (OR = 4.71; 95% CI: 2.73, 8.11) data. Within the Routine cohort, anterior teeth had higher odds of periapical healing than posterior teeth (OR = 1.13; 95% CI: 1.04, 1.22). The 60-month cumulative tooth survival was lower (p = 0.03) in the Routine (90.5%) than the Referred (96.0%) cohort. Within the Routine cohort, the hazard of tooth loss was higher amongst posterior teeth (HR = 4.03; 95% CI: 1.92, 8.45) but lower if posterior teeth had cast restorations (HR = 0.36; 95% CI: 0.19, 0.70). For the Referred cohort, posterior teeth restored with cast restoration (vs not) had significantly lower risk of tooth loss (HR = 0.21; 95% CI: 0.08, 0.55). CONCLUSIONS: For UKAF patients, root canal (re)treatment provided within the Referred pathway was significantly more likely to achieve periapical healing and better tooth survival than those provided within the Routine pathway. Posterior teeth restored with an indirect restoration had a higher proportion of tooth survival. This study supported the utility of the endodontic component of RIOTN for assessing case complexity.

Lesiones perirradiculares asociadas a primeros molares superiores tratados endodónticamente: estudio a través de tomografías computadas / Periradicular lesions associated with endodontically treated maxillary first molars: study through computed tomography

Objetivos: Estudiar con tomografías computadas de haz cónico (CBCT) las lesiones perirradiculares de primeros molares superiores tratados endodónticamente; evaluar la lo- calización y, en los que tenían lesión en la raíz mesiovestibu- lar (MV), evaluar la frecuencia del conducto MV2. Materiales y métodos: A partir de una muestra de 179 tomografías, que incluían primeros molares superiores, se seleccionaron y analizaron aquellas en las cuales estos ha- bían recibido un tratamiento endodóntico previo, presentaban lesiones perirradiculares y conservaban una restauración co- ronaria. Las variables analizadas fueron: la localización de áreas radiolúcidas compatibles con lesiones perirradiculares de origen endodóntico y la correlación entre diferentes loca- lizaciones y la calidad del tratamiento realizado (adecuado, defectuoso o sin tratamiento). Los datos fueron analizados mediante la prueba de chi-cuadrado y la prueba de Spearman. Resultados: De las 179 CBCT que incluían primeros molares superiores, 90 reunían las condiciones requeridas. La frecuencia de las lesiones perirradiculares fue significativa- mente mayor en la raíz MV al compararla con las raíces disto- vestibular y palatina (p<0,05). El conducto MV1 presentó un tratamiento adecuado en todos los casos. El conducto MV2 recibió un tratamiento adecuado en 4 casos (4,44%), defec- tuoso en 4 casos (4,44%) y no tratado en 82 casos (91,1%); con una diferencia estadísticamente significativa (p<0,05). Conclusiones: En la muestra analizada, la localización de lesiones perirradiculares postratamiento endodóntico en primeros molares superiores se encontró con mayor frecuencia asociada a la raíz mesiovestibular, donde en la mayoría de los casos el con- ducto MB2 no fue tratado o presentó un tratamiento defectuoso (AU)

Aim: To study with cone-beam computed tomography (CBCT) the periradicular lesions of maxillary first molars with endodontical treatment; to evaluate its localization and, in those with a mesiobuccal root (MB) injury, assess the fre- quency of the MB2 root canal. Materials and methods: From a sample of 179 tomog- raphies (CBCT) that included maxillary first molars, those in which they had received previous endodontic treatment, pre- sented periradicular lesions and had a coronary restoration were selected and analyzed. The analyzed variables were: localization of radiolucent areas compatible with periradic- ular lesions of endodontic origin and the correlation between different localizations and quality of the performed treatment (adequate, defective, or untreated). Data were analyzed by the chi-square test and the Spearman test. Results: Of the 179 CBCT that included maxillary first molars, 90 met the required conditions. The frequency of periradicular lesions was significantly higher in the MB root when compared with distobuccal and palatal roots (P<0,05). The MB1 canal presented an adequate treatment in all cas- es. The MB2 canal received adequate treatment in 4 cases (4.44%), a defective one in 4 cases (4.44%) and was untreated in 82 cases (91.1%). The differences among these frequencies were statistically significant (P<0.05). Conclusions: In the analyzed sample, the localization of periradicular lesions after endodontic treatment in maxillary first molars was associated more frequently with the mesio- buccal root in which in the majority of cases the MB2 canal was untreated or presented a defective treatment

Evaluación radiográfica de 5000 tratamientos endodónticos realizados en premolares y molares mandibulares y maxilares en una población en Argentina / Radiographic evaluation of 5000 endodontic treatments performed on mandibular and maxillary premolars and molars in a population in Argentina

Objetivo: Evaluar radiográficamente tratamientos en- dodónticos del sector posterior de la cavidad bucal y com- parar la frecuencia de aceptabilidad en cada pieza dentaria involucrada. Materiales y métodos: Se evaluaron 5000 radiogra- fías de archivo de tratamientos endodónticos realizados apro- ximadamente entre 2005 y 2019 en premolares y molares mandibulares y maxilares en Argentina. Se consideraron tratamientos correctos e incorrectos de acuerdo con: 1) con- formación de la preparación quirúrgica; 2) límite apical de la obturación; 3) homogeneidad de la obturación. Se obtuvo la fre- cuencia absoluta y relativa de correctos e incorrectos. El aná- lisis entre frecuencias y pieza dentaria se realizó con la prueba de chi cuadrado y el cálculo del coeficiente V de Cramer. Para la comparación entre grupos de piezas dentarias se utilizó la partición del valor de chi cuadrado obtenido en los corres- pondientes grados de libertad. Nivel de significación P <0.05. Resultados: La partición del valor de chi cuadrado no mostró diferencias significativas entre primeros y segundos premolares mandibulares. Las otras comparaciones exhibie- ron diferencias significativas. Conclusiones: Un alto porcentaje de los tratamientos endodónticos de la población estudiada tiene por lo menos una condición que permite categorizarlos como incorrectos según el criterio establecido en este trabajo. Este porcentaje es más preponderante en anatomías complejas (AU)

Aim: To evaluate radiographically endodontic treat- ments performed in the posterior area of the oral cavity and compare the frequency of acceptability in each tooth involved. Materials and methods: 5,000 archival radiographs of endodontic treatments performed between 2005 and 2019 on mandibular and maxillary premolars and molars in Argentina were evaluated. The percentages of correct and incorrect treatments were considered according to 1) shaping of the preparation; 2) apical limit of the obturation; 3) homogeneity of the obturation. The absolute and relative frequencies of correct and incorrect treatments were calcu- lated. The association between these frequencies and tooth type was analyzed using the chi-square test and Cramer's V coefficient. For the comparison between groups of teeth, the partition of the chi-square value obtained in the corre- sponding degrees of freedom was used. Level of significance was P <0.05. Results: The partition of the chi-square value did not show a significant difference between the first and second lower premolars. The differences were significant in the other comparisons. Conclusions: A high percentage of the endodontic treat- ments in the study population have at least one condition war- ranting their classification as incorrect according to the crite- ria established in this study. This percentage is more prevalent in complex anatomies (AU)

Analysis of Prosthetic Joint Infections Following Invasive Dental Procedures in England.

Importance: Dentists in the United States are under pressure from orthopedic surgeons and their patients with prosthetic joints to provide antibiotic prophylaxis before invasive dental procedures (IDP) to reduce the risk of late prosthetic joint infection (LPJI). This has been a common practice for decades, despite a lack of evidence for an association between IDP and LPJI, a lack of evidence of antibiotic prophylaxis efficacy, cost of providing antibiotic prophylaxis, and risk of both adverse drug reactions and the potential for promoting antibiotic resistance. Objective: To quantify any temporal association between IDP and subsequent LPJI. Design, Setting, and Participants: This cohort study used a case-crossover and time trend design to examine any potential association between IDP and LPJI. The population of England (55 million) was chosen because antibiotic prophylaxis has never been recommended to prevent LPJI in England, and any association between IDP and LPJI would therefore be fully exposed. All patients admitted to hospitals in England for LPJI from December 25, 2011, through March 31, 2017, and for whom dental records were available were included. Analyses were performed between May 2018 and June 2021. Exposures: Exposure to IDP. Main Outcomes and Measures: The main outcome was the incidence of IDP in the 3 months before LPJI hospital admission (case period) compared with the incidence in the 12 months before that (control period). Results: A total of 9427 LPJI hospital admissions with dental records (mean [SD] patient age, 67.8 [13.1] years) were identified, including 4897 (52.0%) men and 4529 (48.0%) women. Of these, 2385 (25.3%) had hip prosthetic joints, 3168 (33.6%) had knee prosthetic joints, 259 (2.8%) had other prosthetic joints, and 3615 (38.4%) had unknown prosthetic joint types. There was no significant temporal association between IDP and subsequent LPJI. Indeed, there was a lower incidence of IDP in the 3 months prior to LPJI (incidence rate ratio, 0.89; 95% CI, 0.82-0.96; P = .002). Conclusions and Relevance: These findings suggest that there is no rationale to administer antibiotic prophylaxis before IDP in patients with prosthetic joints.

Concordancia en la evaluación de tratamientos de endodoncia preclínica: un estudio en diferentes unidades académicas / Agreement in the evaluation of preclinical endodontic treatments: a study at different academic units

Objetivo: El objetivo del presente estudio fue analizar el grado de concordancia entre alumnos y docentes de dife- rentes unidades académicas en la evaluación radiográfica de tratamientos endodónticos realizados en dientes humanos "ex vivo". Materiales y métodos: Un docente y un alumno de grado pertenecientes a siete unidades académicas, dos cáte- dras de Endodoncia de Argentina y una de México, Ecuador, España, Chile y Portugal evaluaron radiográficamente 357 tratamientos endodónticos realizados "ex vivo" por estu- diantes de grado. De acuerdo con su criterio individual, de- terminaron si cada uno de esos tratamientos podía ser con- siderado como correcto o incorrecto. El coeficiente Kappa fue utilizado para el análisis estadístico. Resultados: El valor de Kappa fue entre 0,04 y 0,30 considerado como indicador de escasa concordancia y varió según la unidad académica en la que se habían registrado los datos. Conclusión: El nivel de concordancia en la categoriza- ción del resultado de la evaluación radiográfica de tratamien- tos endodónticos varía entre alumnos de grado y docentes de las distintas unidades académicas (AU)

Aim: To analyse the degree of agreement between stu- dents and teachers at different academic units regarding the radiographic evaluation of endodontic treatments performed on human teeth "ex vivo". Materials and methods: One teacher and one student from seven Academic units, two Departments of Endodontics in Argentina and one each in Mexico, Ecuador, Spain, Chile and Portugal conducted a radiographic evaluation of 357 endodontic treatments performed by undergraduate students. According to their individual criteria, they determined wheth- er the treatments were adequate or inadequate. Kappa coeffi- cient was used for statistical analysis. Results: The Kappa value was between 0.04 and 0.30, considered as an indicator of poor agreement, and varied ac- cording to the academic institution where the data had been recorded. Conclusion: The level of agreement in classifying the re- sults of the radiographic evaluation of endodontic treatments varies between undergraduate students and teachers at the different academic units (AU)

Endodontic practice amongst Nigerian dentists undergoing postgraduate training.

INTRODUCTION: this study aimed at finding out current practice of endodontics amongst Nigerian dentists undergoing postgraduate training (also referred to as dental resident doctors) in different institutions across the nation. METHODS: a questionnaire-based, cross sectional study was conducted amongst dentists undergoing postgraduate training. Questions were asked on demographics, protocol for root canal treatment (RCT), materials employed in different stages. Opinions were also sought on satisfaction with their practice and training needs in endodontics. Data were analyzed with SPSS version 20.0 and presented as tables and charts. Significance level was set at p≤0.05. RESULTS: ninety dentists undergoing postgraduate training (57 males and 33 females) with mean age of 34.81 ± 5.9 years participated in the study. Root canal treatment was mostly done in multiple visits in both single and multi-rooted teeth (p=0.01), only about 15% performed the procedure on multi rooted teeth. Sixty-five (72.2%) never used Rubber dam, stainless steel files were being used by 69%, step down technique of preparation by 53.9% and Sodium hypochlorite was the major irrigant (80%) used. Obturation was majorly with Cold lateral compaction technique (94%), 57.2% delayed definitive restoration for maximum of 1 week and amalgam was still the major material used for posterior teeth as reported by 62.9% of the participants. The majority (55.6%) were not satisfied with their current knowledge and practice and most were those that did not have good undergraduate training (p = 0.05). CONCLUSION: the practice of endodontics needs standardization across the nation as it is being advocated in other countries. There is need for hands on-training on endodontics to encourage adoption of new advances in technology, as well as improve the training of postgraduate dentists in endodontics. Also, emphasis should be placed on use of rubber dam in order to minimize the spread of infection and protect the patients from aspiration of small instruments involved in endodontic procedure.

Access to root canal treatment in a Nigerian sub-population: assessment of the effect of dental health insurance.

BACKGROUND: The final pathway of tooth mortality lies between tooth extraction, and the more expensive and less accessible root canal treatment (RCT). AIM: To determine the extent to which individuals' financial resources as measured by socioeconomic status and dental insurance coverage affects their access to RCT. METHODS: A hospital-based study that used a 15-item questionnaire to collect data among patients scheduled for RCT. All scheduled subjects (N = 291) over a one-year period constituted the sample for the study. Using the SPSS software, associations between the subjects' variables, and the dental insurance status were carried out with Chi square and independent t test respectively at 95% confidence interval. RESULTS: Two hundred and ninety-one subjects were to have 353 RCTs within the study period. A high proportion (79.7%, p < 0.001) of the subjects had dental health insurance, majority (95.3%) of which was government funded. 20.9% of those with previous tooth loss was due to inability to afford cost of RCT. The lowest socioeconomic group had the highest proportion (90%, p = 0.421) of insured that visited for RCT. CONCLUSION: Dental insurance increased access to RCT. Socioeconomic status did not affect dental insurance status and dental visit for RCT.

Incidencia de fracturas dentales reportadas en la Ciudad de Chihuahua durante la pandemia por COVID-19 / Incidence of dental fractures reported in Chihuahua city during COVID-19 pandemic

Se presentan los casos de fracturas verticales sintomáticos que ameritaron la extracción de las órganos dentales afectados en un periodo de cinco meses durante la pandemia por COVID-19 en la ciudad de Chihuahua, México. Material y métodos: Se recolectaron 26 muestras para el estudio, proporcionadas por los cirujanos dentistas integrantes del Grupo de Egresados de la Facultad de Odontología de la Universidad Autónoma de Chihuahua. Resultados: Los resultados muestran diferencias a lo reportado previamente respecto al tipo de diente involucrado, sexo de los pacientes, restauraciones coronales y tratamientos endodóncicos previos. Conclusiones: Se puede suponer que las modificaciones en el estilo de vida de la población, sumadas a la angustia permanente, pueden ser factores que contribuyen a las fracturas dentales (AU)

There are cases of symptomatic vertical fractures that warranted the extraction of affected teeth are presented, over a period of five months during the COVID-19 pandemic in Chihuahua City, Mexico. Material and methods: 26 samples were collected for the study, provided by the dentist who were members of the Graduate Group of the Faculty of Dentistry of the Autonomous University of Chihuahua. Results: The results show differences from what was previously reported regarding the type of tooth involved, sex of patients, coronal restorations and previous endodontic treatments. Conclusions: It can be assumed that changes in the lifestyle of the population, added to permanent distress, may be factors to preserve dental fractures (AU)

Evaluación radiográfica de tratamientos endodónticos realizados por alumnos de grado. Una experiencia docente / Radiographic evaluation of endodontic treatments performed by undergraduate students: a teaching experience

Objetivo: Describir una experiencia de capacitación de alumnos de grado en la evaluación radiográfica de tratamientos endodónticos realizados ex vivo. Material y métodos: Participaron un docente y 13 alumnos, cada uno de los cuales evaluó radiográficamente 100 tratamientos endodónticos realizados ex vivo para determinar si estos eran correctos o incorrectos. Posteriormente, el mismo docente, en una clase teórica, presentó a los alumnos otras imágenes radiográficas a fin de calibrar qué debería considerarse correcto o incorrecto. Luego fueron proyectadas nuevamente las radiografías de los 100 casos, y los alumnos efectuaron una nueva valoración. Para cada alumno, se determinó la frecuencia de concordancia con el docente en los 100 casos, antes y después de la calibración. Se categorizó cada observación como sin cambio, positiva (precalibración sin concordancia y poscalibración con concordancia) y negativa (precalibración con concordancia y poscalibración sin concordancia). En cada caso se calcularon la frecuencia para cada categoría, la frecuencia de concordancia entre cada alumno y el docente antes y después de la calibración, y la diferencia entre frecuencias. Resultados: La frecuencia absoluta de casos con concordancia alumno/docente sin cambios fue entre 65 y 85; con cambio positivo, entre 14 y 29; y con cambio negativo, entre 1 y 8. La concordancia antes y después de la calibración resultó entre 37% y 79,2%. Conclusión: La calibración mejoró parcialmente la capacitación de los alumnos para la evaluación radiográfica de los tratamientos endodónticos (AU)

Aim: To describe one experience of calibration in the radiographic evaluation of 100 endodontic treatments performed ex vivo in undergraduate students. Material and methods: One professor and 13 undergraduate students participated in this study, who independently radiographically evaluated 100 ex vivo endodontic treatments and determined whether each case was correct or incorrect. Later, the same professor presented a theoretical class to the students with other radiographic images in order to calibrate the difference between correct and incorrect treatments. Then the radiographs of the same 100 cases were projected and the students made a new evaluation. The frequency of agreement with the teacher was determined for each student in the 100 cases before and after the calibration. Each observation was categorized as without change, with positive change (pre-calibration without agreement and post-calibration with agreement) and with negative change (pre-calibration with agreement and post-calibration without agreement). The frequency for each category was calculated for each student. In each of the cases, the frequency of students in which concordances with the teacher were observed before and after calibration, and the difference between both frequencies were calculated. Results: The absolute frequency of cases with agreement of the students/teacher without changes varied between 65 and 85, with a positive change between 14 and 29 and a negative change between 1 and 8. The concordance before and after calibration varied between 37.0% and 79.2%. Conclusion: Calibration partially improved the training of students in radiographic evaluation of endodontic treatments (AU)

Apical debris extrusion during instrumentation of oval root canals in primary teeth using manual versus motorized files: an ex vivo study.

This study aimed to assess the apical extrusion of debris during instrumentation of primary canines using three endodontic file types. Forty-five extracted primary canines were randomly assigned to three instrumentation groups (n = 15): Hand K-files; and the motorized Kedo-S files and XP-endo Shaper files. The apically extruded debris produced during the procedure was collected and dried in pre-weighed Eppendorf tubes, and the mass of debris was calculated. The time required for the endodontic procedure was also recorded. Analysis of variance (ANOVA) and Tukey's post hoc test were used with a significance level set at 5%. XP-endo Shaper and Kedo-S files extruded significantly less debris compared with hand K-files with means of 0.84 ± 0.31 and 1.20 ± 0.67 mg respectively, compared to 2.13 ± 0.31 mg (p < 0.0001). No significant difference was found between the two motorized files. Less time was required to complete the procedure with the XP-endo Shaper compared to the hand K-files (p < 0.0001) and Kedo-S files (p < 0.0001). Within the limitations of the present study, it may be concluded that motorized files extruded less debris and required less instrumentation time compared to traditional K-files, which could benefit paediatric patients with root canal treatment needs.

Radiographic and Clinical Findings of Single-Visit Root Canal Treatments with Apical Enlargement in Necrotic Teeth: A Retrospective Cohort Study.

This study evaluated the long-term clinical outcomes of single-visit root canal treatments with apical enlargement on patients with necrotic pulp tissue retrospectively. A total of 137 teeth with necrotic pulp tissue which underwent single-visit root canal treatments were included. The root canals were shaped up until the apical constriction, which was determined by an apex locator. The outcomes were evaluated by two independent and calibrated endodontists clinically and radiographically. Teeth were dichotomized into healed (PAI ≤ 2, no signs or symptoms) and nonhealed (PAI > 2, with/without signs or symptoms) groups. Each patients' preoperative PAI and lesion size were recorded to evaluate the preoperative periapical status as well as several other prognostic factors. Statistical analyses were performed (p = 0.05) on ninety teeth. The mean observation time was 60 months. Out of ninety teeth, 87 (96.7%) were healed and 3 (3.3%) were nonhealed. No correlations were found between the prognostic factors and the outcomes (p > 0.05). Cohen's kappa and Gwet's agreement coefficient scores between the preoperative PAI scores and preoperative lesion sizes showed good agreements, with values of 0.834 and 0.898, respectively. Apical enlargement is a viable treatment option for single-visit root canal treatments.

Evaluación radiográfica de la capacitación preclínica de alumnos de grado en el uso del sistema ProTaper Next en endodoncia / Radiographic evaluation of the preclinical training of undergraduate students in the use of ProTaper Next system in endodontics

Objetivo: Evaluar radiográficamente 162 tratamientos endodónticos realizados ex vivo en premolares inferiores y superiores humanos mediante el empleo del sistema ProTaper Next por parte de alumnos de grado de una cátedra de endodoncia de una universidad argentina. Materiales y métodos: Se evaluaron 162 tratamientos endodónticos realizados ex vivo durante los años 2017, 2018 y 2019 (54 por cohorte) en premolares inferiores y superiores humanos por alumnos de grado de la cátedra de Endodoncia I de la Escuela de Odontología de la Universidad del Salvador / Asociación Odontológica Argentina. Para la instrumentación fue empleado el sistema ProTaper Next. La muestra se tomó de forma aleatoria. En un programa de presentación de computadora se incluyeron las radiografías periapicales pre- y posoperatoria para su evaluación. Un evaluador externo analizó las imágenes radiográficas de los tratamientos y los categorizó como correctos o incorrectos teniendo en cuenta tres requisitos excluyentes: la conformación de la preparación quirúrgica, el límite apical y la homogeneidad de la obturación. Para el análisis estadístico, se utilizó la frecuencia relativa (intervalo de confianza 95%) y la prueba de chi-cuadrado. Resultados: La evaluación radiográfica de los tratamientos endodónticos realizados mostró un número considerable de tratamientos correctos. Los resultados para cada cohorte (años 2017, 2018 y 2019) fueron del 96,3% (87,2- 99,5%), el 94,4% (84,6-98,8%) y el 98,2% (90,1-99,9%) respectivamente. El porcentaje global de tratamientos correctos fue del 96,3% (92,1-98,6%). La diferencia entre las cohortes no fue estadísticamente significativa (P>0,05). Conclusión: El empleo del sistema ProTaper Next por parte de estudiantes de grado evaluados mostró resultados radiográficamente satisfactorios en la instrumentación ex vivo de conductos radiculares de premolares inferiores y superiores humanos (AU)

Aim: To evaluate radiographically, 162 endodontic treatments performed ex vivo by three cohorts of students from a school of dentistry in Argentina, using ProTaper Next rotatory system in mandibular and maxillary human premolars. Materials and methods: 162 mandibular and maxillary human premolars received endodontic treatment by undergraduate students from the Department of Endodontics I of the School of Dentistry USAL/AOA. The treatments were performed ex vivo during the academic years 2017, 2018 and 2019 (54 teeth were chosen for each cohort) using the rotatory system ProTaper Next. The samples were taken randomly. Pre and postoperative radiographs were included in a computer presentation program for its evaluation. An external examiner analysed the radiographic images by the shape of the preparation, the apical limit, and the homogeneity of the obturation, considering the treatments well obturated (correct) or ill obturated (incorrect). To be considered correct the case had to meet all the requirements. The statistic calculations used in this study were: relative frequency (confidence interval 95%) and the chi-square test. Results: The radiographic evaluation showed a considerable number of endodontic treatments correctly done using ProTaper Next system. The percentages for each cohort were 96.3% (87.2-99.5%), 94.4% (84.6-98.8%) y 98.2% (90.1-99.9%) for years 2017, 2018 y 2019 respectively. Global percentage of correctly endodontic treatments was 96.3% (92.1-98.6%). The difference between the cohorts was not statistically significant (P>0.05). Conclusion: The use of ProTaper Next by the dental students evaluated showed satisfactory results in the ex vivo instrumentation of mandibular and maxillary human premolar root canals (AU)

Prevalence of middle mesial and middle distal canals in mandibular molars in an Egyptian subpopulation using micro-computed tomography.

OBJECTIVES: To study the prevalence of middle mesial and middle distal canals in permanent mandibular molars in Egyptian subpopulation using micro-computed tomography. MATERIALS AND METHODS: Two hundred and forty extracted mandibular permanent molars of Egyptian patients were scanned using micro-computed tomography, then the images were reconstructed to allow for the detection of the middle mesial (MM) and middle distal (MD) canals of the molars examined. The path of each extra canal was studied to determine the configuration of each canal. Data were analyzed statistically using the Chi-square test with a level of significance set at P< 0.05. RESULTS: The evaluation of three-dimensional (3D) images of this study showed that no significant difference was found between the percentage of MM (27.5%) and MD canals (22.5%) (P = 0.2064); however, there was a significant difference between the percentage of teeth having both extra canals (10%) and teeth having only one of these canals (P < 0.05). The confluent configuration (71%) was significantly higher than the other configurations (P < 0.05). CONCLUSION: A higher percentage of MM canal was detected followed by the MD canal. The least significant was both canals occurring within the same molar. The percentage of the confluent configuration was the highest. The apt knowledge of the variations of the root canal system anatomy and the respect of the discrepancies associated with diverse demographic areas will ensure the proper management of each tooth with endodontic involvement and its long-term success.

The influence of tobacco smoking on dental periapical condition in a sample of an adult population of the Lódz region, Poland.

OBJECTIVES: Epidemiological studies show that apical periodontitis (AP), alongside tooth decay, is the most common oral disease. The aim of the study was to evaluate the influence of smoking on the prevalence of AP in the population of the Lódz region, Poland. MATERIAL AND METHODS: The study involved 815 first-time, randomly selected patients reporting to the Central Teaching Hospital of the Medical University of Lodz. The studied group was a systematic sample of the population admitted for treatment in 2016. The study consisted of a questionnaire and a radiological part. Each patient filled out a questionnaire containing demographic data, and an interview regarding smoking and diabetes. The radiological part of the study included the analysis of panoramic radiographs which showed the periapical status, and the presence and quality of root canal treatment. RESULTS: Teeth with AP were observed more frequently in patients addicted to tobacco either at the time of the study or in the past (group 1) - 7.2% than in people who had never smoked (group 2) - 5.2% (p < 0.0005). In the teeth without root canal treatment, AP was observed more frequently in group 1 - 3.5% than in group 2 - 1.9% (p < 0.0005). A statistically significant difference was found in the percentage of endodontically treated teeth between group 1 and group 2 (10.7% vs. 9.6%) (p = 0.017). However, no difference was observed in the frequency of AP in the endodontically treated teeth in both groups (37.6% vs. 35.8%) (p = 0.451). CONCLUSIONS: Smokers are a group facing an increased risk of AP and, therefore, there is a need for an early detection and treatment of caries and its complications in this group of patients. The multifactorial etiology of AP indicates the necessity to undertake further studies on the effect of smoking on the periapical status. Int J Occup Med Environ Health. 2020;33(1):45-57.

The value of assessing case difficulty and its effect on endodontic iatrogenic errors: a retrospective cross-sectional study.

The American Association of Endodontists (AAE) released a case difficulty assessment form to help general dentists and students treat cases within their expertise or refer advanced cases to reduce the risk of iatrogenic errors. The purpose of this study was to determine the incidence of iatrogenic complications after the use of the case difficulty assessment form. Arandom sample of 1000 cases that received root canal treatment in undergraduate clinics during the academicyear (2016-2017) was selected. Case difficulty assessment was made for each case before treatment onset. Once the case was approved for treatment in the undergraduate clinics, the endodontic treatments were performed following the standard procedure the endodontic department of the Dentistry School of King Abdulaziz University mandates. Digital radiographs were obtained during routine root canal treatment and were evaluated by four observers to detect any iatrogenic errors, after which the data were analyzed statistically. Iatrogenic errors were correlated significantly with case difficulty (p= 0.003), and were detected in 22.1% of all teeth treated in the undergraduate clinics. Underfilling accounted for the highestpercent of errors detected (8.4%), followed by ledge formation (4.2%). Molar teeth had the highest frequency of errors, and mesio-buccal roots of maxillary molars showed the highest percentage of errors. The AAE developed asignificantly useful tool to determine the difficulty of each case treated in undergraduate clinics, and following their recommendations will minimize the risk of iatrogenic errors.

Evaluación radiográfica de los tratamientos realizados por alumnos de grado con dos técnicas de obturación endodóntica / Radiographic evaluation of the treatments performed by undergraduate students with two filling techniques

Objetivo: Evaluar radiográficamente, en dientes extraídos, el grado de homogeneidad y adaptación de las obturaciones endodónticas realizadas por alumnos de grado, comparando las técnicas de condensación lateral e híbrida. Materiales y métodos: Entre 2003 y 2017, los alumnos de tercer año de la Escuela de Odontología de la Universidad del Salvador / Asociación Odontológica Argentina realizaron 5.384 tratamientos endodónticos ex vivo empleando, para la obturación, las técnicas de condensación lateral e híbrida. En las radiografías posoperatorias, un docente especialista en endodoncia evaluó la homogeneidad y la adaptación de cada obturación para categorizarla como correcta o incorrecta. Para la comparación entre técnicas, dentro de cada año lectivo, se utilizó la prueba exacta de Fisher, y para el análisis porcentual de las observaciones, la prueba de Chi cuadrado. El nivel de significancia fue establecido en P<0,05. Resultados: Del total de 5.384 tratamientos, 4.970 (92,3%) mostraron obturaciones correctas. Con la técnica de condensación lateral, de los 1.741 tratamientos, 1.560 (89,6%) mostraron obturaciones correctas con la técnica híbrida, de los 3.643 tratamientos, 3.410 (93,6%) tuvieron obturaciones correctas. En función del tamaño total de las muestras, sumando todos los años, puede estimarse con 95% de confianza que la diferencia de obturaciones incorrectas entre ambas técnicas está entre el 2,3% y el 5,7%. Con la prueba del Chi cuadrado, se observa una diferencia significativa de obturaciones correctas a favor de la técnica híbrida (P<0,01) Conclusiones: La evaluación radiográfica de los tratamientos endodónticos realizados ex vivo por alumnos de pregrado mostró un alto porcentaje de obturaciones correctas. Así mismo, el empleo de la técnica híbrida dio, en general, mejores resultados de compactación de la masa del material obturador que la técnica de condensación lateral (AU)

Aim: To evaluate radiographically the degree of homogeneity and adaptation of endodontic obturations completed by undergraduate students in extracted teeth using lateral and hybrid condensation techniques. Materials and methods: Between 2003 and 2017, third year students of a the School of Dentistry of the Universidad del Salvador / Asociación Odontológica Argentina performed 5384 ex vivo endodontic treatments using lateral condensation and hybrid technique. In the postoperative radiographs, a specialist in endodontics assessed the homogeneity and adaptation of each obturation and categorize it as correct or incorrect. The data were submitted to statistical analysis to compare results obtained with the two techniques. Fisher and Chi-square tests were used and significance level was set at P<0.05. Results: Out of 5384 treatments, 4970 (92.3%) showed correct obturation. Within the 1741 treatments completed with the lateral condensation technique, 1560 (89.6%) were correct while within the 3634 where a hybrid technique was used, 3410 (93.6%) were correct. When the whole sample was considered (sum of treatment carried out during each of the academic years) a statistically significant difference (P<0.01) favoring the hybrid technique was found. The difference in incorrect cases can be estimated to be between 2.3% and 5.7% with 95% confidence. Conclusions: The radiographic evaluation completed by undergraduate students in extracted teeth showed a high percentage of correct fillings. The use of the hybrid technique showed, in general, better compaction of the obturation material than the lateral condensation technique (AU)

Validation of self-reported history of root canal treatment in a southern Brazilian subpopulation.

The aim of this study was to assess self-reported history of root canal treatment (SRHRCT) as a method for detecting the presence of root canal treatment (RCT) and apical periodontitis (AP) in a southern Brazilian subpopulation. In this cross-sectional study, 136 military police officers from the city of Porto Alegre, Brazil, were included. The participants were interviewed and full-mouth periapical radiographs were taken. A calibrated examiner determined the presence of RCT and AP by applying standardized criteria. The diagnostic accuracy of SRHRCT was calculated separately for RCT and AP. Accuracy, sensitivity, specificity, positive and negative predictive values (+PV and -PV), efficiency, and positive and negative likelihood ratios (+LR and -LR) were estimated. The mean age of the participants was 34.1 ± 10.4 years and 88.2% were males. Overall, SRHRCT demonstrated high sensitivity and specificity for RCT, but not for AP: sensitivity (RCT = 0.960, AP = 0.757) and specificity (RCT = 0.835, AP = 0.631). The estimated values for PV and LR were: +PV (RCT=0.777, AP=0.396), -PV (RCT = 0.972, AP = 0.890), +LR (RCT = 5.853, AP = 2.057), and -LR (RCT = 0.046, AP = 0.383). SRHRCT proved to be a good predictor of the presence of RCT, but a weak predictor of AP in this subpopulation.

Indications for root canal treatment in a Swedish county dental service: patient- and tooth-specific characteristics.

AIM: To study patient- and tooth-specific characteristics of teeth indicated for root canal treatment, in the public dental service of the county of Västra Götaland, Sweden. METHODOLOGY: During a designated 8-week period, general dental practitioners working at 20 different public dental clinics consecutively registered indications for undertaking root canal treatment. The patients' subjective level of pain was also registered (visual analogue scale) at the very first appointment. The following information was retrieved from computerized dental records and radiographs: gender, age, number of remaining teeth, tooth group, previous restoration, number of restored surfaces, dental caries and tooth substance loss. Gender and age were compared using both descriptive and analytical statistics. RESULTS: The material comprised 243 teeth in 243 patients: 128 (52.7%) women and 115 (47.3%) men, mean age 48.3 years. Molar teeth predominated (47.7%). Most of the teeth (83.5%) had previously been restored and exhibited significant loss of tooth substance, more than a third of the crown (71.3%). Dental caries was present in 127 teeth (62.9%). Dental trauma was implicated in only seven cases (2.9%). Initial treatment was frequently undertaken at an emergency visit, for relief of symptoms (64.9%). The most commonly registered indication was pulpal necrosis with apical periodontitis (38.1%), followed by pulpitis (37.7%). Retreatment of a root filled tooth was reported in 18 teeth (7.4%). CONCLUSIONS: In the general Public Dental Service of Sweden, root canal treatment is most frequently undertaken in molars. The primary indication is relief of symptoms. Retreatment of root filled teeth is uncommon.