Accuracy of Four Electronic Apex Locators During Root Canal Length Determination / Precisión de Cuatro Localizadores de Ápice en la Determinación de la Longitud de Trabajo

ABSTRACT: The apical limit of tooth roots for instrumentation and obturation is a controversial subject due to the high morphological complexity presented by the apical zone of the root. The development of electronic apex locators (EALs) has made working length (WL) determination more predictable, producing more accurate results; however, the interpretation mechanisms of different devices may affect measurements taken under different clinical conditions. One hundred premolars were used to compare the effectiveness of Propex II, Raypex 6, Propex Pixi and Root ZX II in locating the apical foramen (AF). No statistically significant differences were observed when the accuracy of measurement was compared between the different groups of EALs, however Root ZX II and Raypex 6 presented the best overall performance.

RESUMEN: El límite apical radicular para la instrumentación y obturación es un tema controversial, debido a la alta complejidad morfológica que presenta la zona apical de la raíz. El desarrollo de localizadores de ápice electrónicos (EALs) ha hecho la determinación de la longitud de trabajo (WL) más predecible y con resultados más precisos. Sin embargo, el mecanismo de interpretación de cada dispositivo puede afectar la determinación de las mediciones en diferentes condiciones clínicas. Cien premolares fueron utilizados para comparar la efectividad de Propex II, Raypex 6, Propex Pixi y Root ZX II en localizar el foramen apical (AF). No se observaron diferencias estadísticamente significativas cuando se comparó la precisión de medición entre los diferentes grupos de EALs, sin embargo, Root ZX II y Raypex 6 mostraron un mejor desempeño global.

The Reliability and Validity of the Measurements in Unilateral Cleft Lip and Palate Laser Scanned 3D Dental Casts

Abstract Objective: To evaluate the reliability and validity of the Next Engine 3D Laser scanner. Material and Methods: A total of 30 dental casts of unilateral cleft lip and palate (UCLP) children with 90 linear variables were measured using digital caliper while the laser-scanned 3D dental casts (LS3DM) were measured using Mimics Software. All scanned data coordinates (in x, y, z) were transferred into Mimics software in STL format to be measured. All the variables were measured using a computer mouse accurate to 0.5 mm. The intra-class correlation coefficient (ICC) was used to evaluate the intra- and inter-examiner reliabilities and also for the validity of two methods Results: Intra-examiner reliabilities of digital caliper and LS3DM were found excellent (ICC 0.916-0.995) and inter-examiner reliabilities of LS3DM were good to excellent (ICC 0.816-0.990). The validity of LS3DM measurements was confirmed based on the ICC values were in the range of 0.913-0.996. The overall time frame for conducting measurements was shorter using a laser-scanned model (10 min.) than using a digital caliper (5 hours) Conclusion: The LS3DM is a valid reliable tool for future high impact research in our institution.

Localizador apical electrónico Raypex 6: un estudio in vivo / The Raypex 6 electronic apex locator: an in vivo study

El propósito de ese estudio fue evaluar in vivo la determinación de la longitud de trabajo utilizando el localizador apical electrónico Raypex 6. Material y métodos: Fueron determinadas la longitud de trabajo electrónica (Raypex 6) y radiográfica de 249 conductos radiculares de 125 pacientes con indicación de realizar tratamiento endodóntico. Los pacientes fueron atendidos según los protocolos clínicos habituales. La evaluación fue realizada en dos fases con dos niveles de aceptación, uno con una tolerancia de ± 0.5 mm y otra no. Resultados: En la fase 1 de nivel de tolerancia de evaluación, las mediciones fueron consideradas adecuadas (± 0.5 mm) en el 96.4 por ciento (93.3-98.3), cortos (- 0.5/1 mm) el 1.6 por ciento (04-4) y pasados (+ 0.5/1 mm) el 2 por ciento (0.7-4). Mientras que en la fase 2 de nivel de tolerancia de evaluación para las mediciones consideradas adecuadas (sin rango de tolerancia) fue de un 86.4 por ciento (81.5-91), cortos (- 0.5/1 mm) el 4 por ciento (2-7.8) y pasados (+ 0.5 y a 1 mm) el 9 por ciento (6-13.5). No fueron encontradas diferencias significativas al considerar eldiagnóstico y el género masculino o femenino. Conclusiones: Bajo lascondiciones en que se realizó este estudio la utilización del localizadorapical electrónico Raipex 6 ofreció una aceptable confiabilidad clínica en los dos niveles de tolerancia evaluados...

Influence of Blood on the Accuracy of Raypex 5 and Root ZX Electronic Foramen Locators: An In Vivo Study

Abstract The aim of this study was to evaluate in vivo the accuracy of the Raypex 5 and Root ZX electronic foramen locators (EFLs) in the presence of blood in the root canal space. Forty single-canal teeth scheduled for extraction were selected. Access cavity was prepared and coronal enlargement was carried out. Approximately two drops of blood were collected by finger prick and injected into the root canal space. The electronic working length (EWL) of each tooth by each device was established twice before (NB group) and after (WB group) injecting blood into the root canal. The tooth was extracted and the actual working length (AWL) was determined. Data were analyzed using McNemar's test. The accuracy rates of Raypex 5 and Root ZX within 0.5 mm in the NB group were 88.9% and 91.5%, with 83.3% and 86.2% in the WB group, respectively. There were no significant differences between the accuracy of each EFL in the two groups (p>0.05). Considering the NB and WB groups, there were no statistically significant differences in the accuracy of the EFLs (p>0.05). The presence of blood in the root canal space did not influence the accuracy of the EFLs.

Resumo Este estudo objetivou avaliar in vivo a precisão dos localizadores foraminais eletrônicos (EFLs) Raypex 5 e Root ZX em presença de sangue no canal radicular. Foram utilizados 40 dentes unirradiculares destinados a extração. Foi preparada cavidade de acesso e feita ampliação coronária. Cerca de duas gotas de sangue obtidas por punção digital foram injetadas no canal. O comprimento eletrônico de trabalho (EWL) foi medido duas vezes antes (Grupo NB) e depois (Grupo WB) da injeção do sangue. O dente foi extraído e o comprimento real de trabalho (AWL) foi determinado. Os dados foram analisados com o teste de McNemar. As taxas de precisão a ±0,5 mm de Raypex 5 e Root ZX foram 88,9% and 91,5% no Grupo NB, e 83,3% e 86,2% para o Grupo WB, respectivamente. Não houve diferença significativa entre a precisão de cada um dos EFLs em ambos os grupos (p>0,05). Considerando os grupos NB e WB, não houve diferença significativa entre as precisões dos EFLs (p>0,05). A presença de sangue no canal radicular não influencou a precisão dos EFLs.

Comparison of two different methods of average working length determination in second molars and premolars / Comparación de dos métodos para determinar la longitud de trabajo promedio en segundos molares y premolares

Within the procedures involved in a successful endodontic treatment is the working length (WL) determination. The root canal end must be detected accurately, and a precise control of the WL must be maintained. There are several methods to determine WL. Researchers have published the average teeth length (ATL) to the human permanent dentition. These measurements are used as an anatomical reference. If the WL is evaluated using a radiographic image, it is accepted as clinical success if the limit of the canal sealing is 1 mm coronal to the root apex. One method to determine WL is based in substract 1 mm to ATL. Another method widely used, assert to achieve a more precise WL determination, through the use of an electronic apex locator (AL). Nevertheless, published measures of ATL are still used as anatomical reference, and are used to determine WL in the absence of an AL. The aim of this study was to determine the average WL of second molars and premolars with endodontic treatment indication using a PropexII® AL, and compare these measurements to WL determination using ATL method. A descriptive cross-sectional study with a non-random sample of consecutive cases was executed. Results showed that there were no statistically significant differences between the WL obtained with AL and ATL method in studied teeth, except mesio-buccal canal of second maxillary molars (19.94 mm average using AL, 1.54 mm greater than ATL method 18.40 mm; p= 0.002). The ATL method to determine WL could be used to determine the WL of second molars and premolars in studied population. Further research should be performed to determine if ATL method is safe and reliable to be used in absence of an AL or in patients where this instrument cannot be used.

Entre los procedimientos involucrados en un tratamiento endodóntico exitoso está la determinación de longitud de trabajo (LT). Esta debe mantenerse durante todo el tratamiento, y el extremo del canal radicular (CR) debe detectarse con precisión. Existen varios métodos para determinar LT; los investigadores han publicado la longitud total promedio (LTP) de la dentición permanente humana. Estas mediciones se utilizan como referencia anatómica. Si LT se evalúa usando una imagen radiográfica, se acepta como éxito clínico cuando el límite de la obturación radicular queda 1 mm coronal al ápice radicular. Un método para determinar LT se basa en restar 1 mm a la LTP. Otro método, que permite una determinación de LT más precisa, se realiza utilizando un localizador apical electrónico (LA). Pese a esto último, las medidas publicadas de LTP todavía se utilizan como referencia anatómica, para determinar LT en ausencia de un LA. El objetivo fue determinar LT promedio de los CR de segundos molares y premolares con indicación de endodoncia utilizando LA PropexII®, y comparar estas mediciones con la LT determinada utilizando el método de LTP. Se realizó un estudio descriptivo de corte transversal con una muestra no probabilística de casos consecutivos. No hubo diferencias estadísticamente significativas entre la LT obtenida con LA y el método LTP en los dientes estudiados, salvo en los canales mesio-bucales de segundos molares superiores (19,94mm promedio usando LA, 1,54 mm mayor que el método LTP: 18,40 mm; p= 0,002). El método para definir LT a través de LTP podría utilizarse para determinar LT de segundos molares y premolares en la población estudiada. Se requieren investigaciones posteriores para determinar si el método que utiliza LTP es confiable para ser utilizado en ausencia de un LA o en pacientes en los que este instrumento no pueda ocuparse.

Effectiveness of three electronic apex locators to determine root canal working length / Efectividad de tres localizadores apicales electrónicos para determinar la longitud radicular de trabajo

This study was to evaluate in vivo the accuracy of three electronic apex locators (EALs) in determining working length (WL) using hand files and a wear technique. Thirty two premolars that were completely formed apically and that were scheduled for extraction for orthodontic reasons from patients between ages of 15 and 20 years old were included. Electronic measurement of WL was performed using the EAL according to the manufacturer’s instructions. The following three EAL were used: A. Root ZX II; B. Raypex 5, and C. Propex II. There were significant difference (p=0.0002) when comparing median differences among the three EAL. Statistical analysis revealed significant differences between Root ZX II vs. Raypex 5 and Root ZX II vs. Propex II (p=0.0044; p=0.0002), while between aypex 5 and Propex II, there were no statistically significant differences with respect to the accuracy of the EAL in determining WL (p=0.1087). The present findings suggest that Root ZX II presented the highest agreement rate for determining the final WL...

Estudio fue evaluar in vivo la exactitud de tres localizadores apicales electrónicos(LAEs) para determinar la longitud de trabajo (LT) usando instrumentos manuales y una técnica de desgaste. Treinta y dos premolares con formación apical completa e indicados para extracción por razones ortodóncicas de pacientes de edad entre 15 y 20 años fueron incluidos en el estudio. Seusaron tres LAE; A. Root ZX II; B. Raypex 5, y C. Propex II. Se encontraron diferencias significativas (p=0.0002) cuando se compararon las medianas entre los tres LAE. El análisismostró diferencias entre Root ZX II vs. Raypex 5 y Root ZX II vs. Propex II (p=0.0044; p=0,0002), mientras queentre Raypex 5 y Propex II, no se encontraron diferencias estadísticamente significativas en la determinación de la LT (p=0.1087). Los presentes hallazgos sugieren que Root ZX II mostró la mayor exactitud para determinar la LT final...

Measurement accuracy and reliability of tooth length on conventional and CBCT reconstructed panoramic radiographs

INTRODUCTION: This in vivo study assessed accuracy and reliability of tooth length measurements obtained from conventional panoramic radiographs and CBCT panoramic reconstructions to that of a digital caliper (gold standard). METHODS: The sample consisted of subjects who had CBCT and conventional panoramic radiographic imaging and who required maxillary premolar extraction for routine orthodontic treatment. A total of 48 teeth extracted from 26 subjects were measured directly with digital calipers. Radiographic images were scanned and digitally measured in Dolphin 3D software. Accuracy of tooth length measurements made by CBCT panoramic reconstructions, conventional panoramic radiographs and digital caliper (gold standard) were compared to each other by repeated measures one-way ANOVA with Bonferroni correction and by single measures intraclass correlation coefficient. RESULTS: Repeated root length measures with digital calipers, panoramic radiographs and CBCT constructed panoramic-like images were all individually highly reliable. Compared to the caliper (gold standard), tooth measurements obtained from conventional panoramic radiographs were on average 6.3 mm (SD = 2.0 mm) longer, while tooth measurements from CBCT panoramic reconstructions were an average of 1.7 mm (SD = 1.2 mm) shorter. CONCLUSIONS: In comparison to actual tooth lengths, conventional panoramic radiographs were relatively inaccurate, overestimating the lengths by 29%, while CBCT panoramic reconstructions underestimated the lengths by 4%. .

INTRODUÇÃO: este estudo in vivo avaliou a precisão e a confiabilidade de medições do comprimento dentário realizadas em radiografias panorâmicas convencionais e em reconstruções panorâmicas de tomografias computadorizadas de feixe cônico (TCFC), comparando-as com medições feitas com um paquímetro digital, consideradas o padrão-ouro. MÉTODOS: a amostra incluiu indivíduos que já tivessem realizado tanto exames imaginológicos de TCFC quanto radiografias panorâmicas, e cujo tratamento ortodôntico exigisse a extração de pré-molar superior. No total, 48 dentes extraídos, de 26 pacientes, foram mensurados diretamente com paquímetros digitais. As radiografias foram escaneadas e digitalmente avaliadas com a ajuda do software Dolphin 3D. Por meio da análise de variância simples com correção de Bonferroni e Coeficiente de Correlação Intraclasse simples, comparou-se a precisão das medições de comprimento dentário realizadas em reconstruções panorâmicas de TCFC, em radiografias panorâmicas convencionais e com paquímetro digital. RESULTADOS: medições repetidas de comprimento dentário feitas com o paquímetro digital, radiografias panorâmicas e reconstruções panorâmicas de TCFC foram todas consideradas, individualmente, altamente confiáveis. Em comparação ao paquímetro, as medidas obtidas por meio de radiografias panorâmicas convencionais foram, em média, 6,3 ± 2,0mm mais longas, enquanto as medidas obtidas por meio das reconstruções panorâmicas de TCFC foram, em média, 1,7 ± 1,2mm mais curtas. CONCLUSÕES: em comparação com o real comprimento dentário, as radiografias panorâmicas convencionais foram relativamente ...

Tooth-size discrepancy: A comparison between manual and digital methods

INTRODUCTION: Technological advances in Dentistry have emerged primarily in the area of diagnostic tools. One example is the 3D scanner, which can transform plaster models into three-dimensional digital models. OBJECTIVE: This study aimed to assess the reliability of tooth size-arch length discrepancy analysis measurements performed on three-dimensional digital models, and compare these measurements with those obtained from plaster models. MATERIAL AND METHODS: To this end, plaster models of lower dental arches and their corresponding three-dimensional digital models acquired with a 3Shape R700T scanner were used. All of them had lower permanent dentition. Four different tooth size-arch length discrepancy calculations were performed on each model, two of which by manual methods using calipers and brass wire, and two by digital methods using linear measurements and parabolas. RESULTS: Data were statistically assessed using Friedman test and no statistically significant differences were found between the two methods (P > 0.05), except for values found by the linear digital method which revealed a slight, non-significant statistical difference. CONCLUSIONS: Based on the results, it is reasonable to assert that any of these resources used by orthodontists to clinically assess tooth size-arch length discrepancy can be considered reliable. .

INTRODUÇÃO: na Odontologia, os avanços tecnológicos vêm se manifestando, principalmente, em instrumentos de diagnóstico, como o desenvolvimento dos scanners 3D, capazes de transformar modelos de gesso em modelos digitais tridimensionais. OBJETIVO: o objetivo da presente pesquisa foi avaliar a confiabilidade da análise da Discrepância de Modelo realizada em modelos digitais tridimensionais, comparando-a com a obtida em modelos de gesso. MÉTODOS: utilizou-se modelos de gesso das arcadas dentárias inferiores e seus correspondentes modelos digitais tridimensionais, adquiridos por meio do scanner 3Shape R700T. Foram realizados quatro diferentes cálculos da Discrepância de Modelo para cada modelo selecionado, dois desses por meio de métodos manuais, utilizando paquímetro e fio de latão, e dois por meio de métodos digitais, utilizando medições lineares e por meio da confecção de uma parábola. RESULTADOS: os dados obtidos foram avaliados estatisticamente por meio do teste de Friedman, e observou-se não haver diferença estatisticamente significativa entre os métodos utilizados (p > 0,05), exceto os valores obtidos pelo método digital linear, onde observou-se uma pequena diferença estatística, porém, não são valores considerados clinicamente significativos. CONCLUSÃO: com base nos resultados, é possível afirmar que, quaisquer desses recursos que o ortodontista venha a utilizar em sua vida clínica para obtenção da Discrepância de Modelo, esses são considerados métodos confiáveis. .

Avaliação da precisão de três localizadores foraminais na determinação do comprimento de trabalho: um estudo in vitro / Evaluation of the accuracy of three apex locators to determine the working length: an in vitro study

Um dos fatores determinantes para o sucesso do tratamento endodôntico é a determinação correta do comprimento de trabalho, pois através dele que elegemos o limite da instrumentação e da obturação evitando assim injúrias aos tecidos periapicais. Objetivo: O presente estudo teve como objetivo realizar uma análise comparativa in vitro da precisão de três localizadores foraminais, sendo eles Root ZX mini, Joypex 5 e T-Root VI. Método: Foram selecionados 30 dentes incisivos inferiores humanos extraídos. Após o acesso coronário, foi realizada a mensuração com o auxilio de um instrumento tipo K n°10 até sua ponta ser observada no forame apical com ajuda de um microscópio cirúrgico com x 50 de magnificação. Os dentes foram imersos em recipiente de plástico contendo alginato, e mensurados com os três localizadores foraminais calibrados em "Apex". Foi considerado Preciso, se a mensuração foi coincidente com comprimento real do dente; Aceitável, se a distância da medida for ate 0,5mm aquém do forame apical; e Errônea, se os valores das medidas forem menores que a medida Aceitável ou forem além do comprimento real do dente. Os dados foram submetidos aos testes de ANOVA e Tuckey (p<0,05). Resultados: Os valores observados mostraram não haver diferença estatisticamente significante (p>0.05) entre as medidas realizadas com os localizadores e o comprimento real do dente. Conclusão: Os resultados confirmam que todos dispositivos eletrônicos avaliados podem determinar com precisão o comprimento do canal radicular...

One of the most relevant factors for the success of endodontic treatment is the correct determination of the working length, since it will determine the limit of shaping and filling avoiding injuries to the periapical tissues. Objective: The aim of the present study was to compare the accuracy of three electronic apex locators: Root ZX mini, Joypex 5 and T- Root IV. Method: Thirty extracted single-rooted human incisors, extracted for reasons not related to this study, were selected and accessed. Then, the measurement of the specimens was determinated by inserting a size 10 K-file into the root canal until its tip was visible at the apical foramen by using surgical microscope at X50 magnification. The teeth were embedded in an alginate model and the analysis using the apex locators were made. The measurement restricted to 00 mm of the apical foramen (real tooth length) was classified as accurate, if the distance was determinated 0.5 mm short of the apical foramen as acceptable, and if the values of the measures were larger or smaller than the acceptable measures was classified as inaccurate. Statistical analysis was performed using ANOVA and Tuckey test (p < 0.05) Results: There were no significant differences among the three groups when electronic apex locators were used (p> 0.05). Conclusions: The results confirm that all these electronic devices can accurately determine the root canal length...

Nuevo instrumento de medición dentaria: comparación con instrumentos y métodos tradicionales / A new tooth measurement instrument: comparison with conventional instruments and methods

El objetivo de esta investigación fue evaluar la fiabilidad, validez y eficiencia de las mediciones obtenidas con el calibre Haenggi3,4, y comparar a las mismas logradas con métodos tradicionales . Este estudio también incluyó la medición de piezas dentarias de acrílico montadas en un modelo de cera (Typodont). Cada una de las piezas de acrílico fue medida con un calibre digital con una precisión +-0,01 mm fuera de la arcada, estableciendo las medidas de control. A continuación se realizó la medición con cada método e instrumento, en las distintas posicioens dentarias formadas sobre el modelo y se determinó la diferencia entre los valores obtenidos y la forma establecida con el calibre Haenggi3,4 fueron los más cercanos a la norma establecida. Se obtuvo un coeficiente de correlación lineal de Pearson1 muy cercano a 1 (r=0,96), en comparación con la norma establecida. Esto demostró la validez del dispositivo de medición. El tiempo de medición fue siete veces menor al promedio de los demás instrumentos. Además, el cálculo automático de los índices, mediante el software del calibre Haenggi3,4, supone una ventaja con respecto al tiempo necesario para obtener los resultados de los distintos índices dentarios utilizando los métodos tradicionales

Assessment of first molars sagittal and rotational position in Class II, division 1 malocclusion

OBJECTIVE: This study assessed the anterior-posterior positioning of the upper and lower first molars, and the degree of rotation of the upper first molars in individuals with Class II, division 1, malocclusion. METHODS: Asymmetry I, an accurate device, was used to assess sixty sets of dental casts from 27 females and 33 males, aged between 12 and 21 years old, with bilateral Class II, division 1. The sagittal position of the molars was determined by positioning the casts onto the device, considering the midpalatal suture as a symmetry reference, and then measuring the distance between the mesial marginal ridge of the most distal molar and the mesial marginal ridge of its counterpart. With regard to the degree of rotation of the upper molar, the distance between landmarks on the mesial marginal ridge was measured. Chi-square test with a 5% significance level was used to verify the variation in molars position. Student's t test at 5% significance was used for statistical analysis. RESULTS: A great number of lower molars mesially positioned was registered, and the comparison between the right and left sides also demonstrated a higher number of mesially positioned molars on the right side of both arches. The average rotation of the molars was found to be 0.76 mm and 0.93 mm for the right and left sides, respectively. CONCLUSION: No statistically significant difference was detected between the mean values of molars mesialization regardless of the side and arch. Molars rotation, measured in millimeters, represented » of Class II.

OBJETIVO: esse estudo avaliou o posicionamento anteroposterior dos primeiros molares superiores (1º MS) e inferiores, e o grau de rotação dos 1º MS, em indivíduos com má oclusão de Classe II, divisão 1. MÉTODOS: mensuraram-se, em aparelho de precisão Assimetria I, 60 pares de modelos, de 27 indivíduos do sexo feminino e 33 do masculino, entre 12 e 21 anos de idade, com má oclusão de Classe II, divisão 1. Utilizando a sutura palatina mediana como referência de eixo de simetria, os modelos foram posicionados no aparelho para mensuração da distância entre a crista marginal mesial do molar mais distal e a crista marginal mesial do molar do lado oposto, a fim de verificar o posicionamento sagital dos molares. Em relação à giroversão, mediu-se a distância entre pontos na crista marginal mesial. O teste qui-quadrado a 5% foi utilizado para verificar a variação de posicionamento dos molares, por arcos e por lado. O teste t de Student a 5% foi utilizado para comparar esses valores. RESULTADOS: houve maior número de molares inferiores mesializados e, comparando os lados, maior número de molares mesializados no lado direito em ambas as arcadas. As rotações médias dos molares foram de 0,76mm do lado direito e 0,93mm do esquerdo. CONCLUSÃO: não houve diferença estatisticamente significativa entre os valores médios das mesializações dos molares quanto a lado ou arco. Quando observada isoladamente, a rotação dos molares, quantificada em milímetros, representou uma situação de » de Classe II.

Accuracy of five electronic foramen locators with different operating systems: an ex vivo study

Objective: The aim of this study was to evaluate, ex vivo, the precision of five electronic root canal length measurement devices (ERCLMDs) with different operating systems: the Root ZX, Mini Apex Locator, Propex II, iPex, and RomiApex A-15, and the possible influence of the positioning of the instrument tips short of the apical foramen. Material and Methods: Forty-two mandibular bicuspids had their real canal lengths (RL) previously determined. Electronic measurements were performed 1.0 mm short of the apical foramen (-1.0), followed by measurements at the apical foramen (0.0). The data resulting from the comparison of the ERCLMD measurements and the RL were evaluated by the Wilcoxon and Friedman tests at a significance level of 5%. Results: Considering the measurements performed at 0.0 and -1.0, the precision rates for the ERCLMDs were: 73.5% and 47.1% (Root ZX), 73.5% and 55.9% (Mini Apex Locator), 67.6% and 41.1% (Propex II), 61.7% and 44.1% (iPex), and 79.4% and 44.1% (RomiApex A-15), respectively, considering ±0.5 mm of tolerance. Regarding the mean discrepancies, no differences were observed at 0.0; however, in the measurements at -1.0, the iPex, a multi-frequency ERCLMD, had significantly more discrepant readings short of the apical foramen than the other devices, except for the Propex II, which had intermediate results. When the ERCLMDs measurements at -1.0 were compared with those at 0.0, the Propex II, iPex and RomiApex A-15 presented significantly higher discrepancies in their readings. Conclusions: Under the conditions of the present study, all the ERCLMDs provided acceptable measurements at the 0.0 position. However, at the -1.0 position, the ERCLMDs had a lower precision, with statistically significant differences for the Propex II, iPex, and RomiApex A-15.

Nuevo instrumento de medición dentaria para el cálculo de índices odontológicos / A new tooth measurement instrument for the calculation of dental indexes

La falta de eficiencia de los instrumentos de medición dentaria ha llevado a los odontólogos a prescindirde su ayuda como elemento diagnóstico. Del estudio de los métodos e instrumentos actuales surge la necesidad de desarrollar un nuevo dispositivo que mejoré aquellos aspectos que dificultan la implementación de los métodos de medición. Se presenta un nuevo instrumento de medición dentaria para el cálculo de índices odontológicos.

Influence of the apical enlargement size on the endotoxin level reduction of dental root canals

Gram-negative bacteria play an essential role in endodontic infections because they have virulence factors such as endotoxin. Due to its potential cytotoxic activity, special attention has been given to the removal/neutralization of this endotoxin in the root canal system. OBJECTIVE: The aim of this study was to evaluate the influence of the apical enlargement size (AES) by using rotary instruments on the endotoxin level reduction of dental root canals. MATERIAL AND METHODS: Forty root canals of the mandibular premolar teeth were used. Escherichia coli endotoxin (055: B55) was inoculated into thirty root canals. Ten teeth served as the negative control group. After the incubation period, the first endotoxin samples were collected from the root canals with a sterile/apyrogenic paper point for the analysis of the endotoxin units (EU/mL) present before instrumentation (S1). Specimen instrumentation was performed with the Mtwo® rotary system in the sequence 10/.04, 15/.05, 20/.06, 25/.06, 30/.05, 35/.04 and 40/.04. To monitor the effectiveness of increasing apical enlargement on endotoxin removal, the second endotoxin samples were collected from all the root canals after instrumentation with the following instruments: #25/.06- (S2); #30/.05- (S3); # 35/.04- (S4); and #40/.04- (S5). Limulus amebocyte lysate (LAL) was used to quantify the levels of endotoxin. The results were statistically compared by using repeated measures of ANOVA with post hoc Tukey testing. RESULTS: Increasing levels of endotoxin removal was achieved by large sized apical enlargement: S2 (AES #25/.06)- 89.2%, S3 (AES #30/.05)- 95.9%, S4 (AES #35/.04)- 97.8% and S5 (AES #40/.04)- 98.2%. Substantial reduction of endotoxin content was obtained in S4 and S5 compared to S2 (p<0.05), however, the root canal preparation was not able to eliminate the endotoxin. CONCLUSIONS: Under the conditions of this study, it was concluded that the reduction of endotoxin levels of the dental root canals could be predicted by increasing the apical enlargement size.

Precisão e confiabilidade de um novo localizador foraminal eletrônico: estudo in vivo / Accuracy and reliability of a new electronic apex locator: an in-vivo study

Objetivo: Verificar in vivo a precisão e confiabilidade de leitura do localizador foraminal eletrônico Joypex 5® utilizando o microscópio eletrônico de varredura na aferição das medidas obtidas pelo aparelho. Método: Foram triados pacientes com indicação para extração por motivos ortodônticos e periodontais, o que resultou em amostra de 14 canais. Os dentes foram previamente radiografados com a intenção de detectar perfurações, tratamentos endodônticos prévios e calcificações. Realizadas as aberturas coronárias, os terços cervical e médio foram preparados e procederam-se as leituras no ponto correspondente no display do aparelho ao forame apical. Após a obtenção da medida a lima foi removida e subtraiu-se 1mm do comprimento lido em paquímetro digital para, então, fixar o instrumento e realizar a exodontia. Na seqüência foi realizado um desgaste em uma das paredes da região apical, objetivando visualizar a ponta do instrumento e a continuidade do canal até a real saída do forame apical. A distância entre a ponta da lima e a real saída foraminal foi medida com o auxílio de microscopia eletrônica de varredura. Resultados: A média das medidas foi 0,87 mm (DP 0,42mm). O teste T para amostras independentes revelou que os dados mostraram-se semelhantes (p > 0,05) entre os valores experimentais encontrados (da ponta do instrumento ao forame apical) e o valor hipotético testado de 1 mm. Conclusões: O estudo concluiu que o localizador foraminal eletrônico Joypex 5® demonstrou ser preciso e confiável na determinação de um comprimento de trabalho eficiente e seguro para o tratamento endodôntico. de trabalho eficiente e seguro para o tratamento endodôntico.

Objective: To evaluate in vivo the measurement accuracy and reliability of the electronic apex locator Joypex 5® using a scanning electron microscope to assess the measurements obtained with the tested device. Method: Patients with indication for tooth extraction for orthodontic and periodontal reasons were screened, providing a sample of 14 root canals. The teeth were first radiographed for detecting perforations, previous endodontic treatments and calcifications. After preparation of access cavities, the coronal and middle thirds were prepared and the electronic measurements were made on the point corresponding to the apical foramen of the apex locator's display. After the electronic reading, the file was removed from the canal, 1 mm was subtracted from the measurement obtained using a digital caliper, and the apex locator was fixed for extraction of the tooth. Next, grinding was performed on an apical wall in order to visualize the tip of the file and canal integrity up to the actual apical foramen opening. The distance between the file tip and the actual apical foramen opening was measured by scanning electron microscopy. Results: The mean of the obtained measurements was 0.87 mm (DP 0.42 mm). The t test for independent samples revealed statistical similarity (p>0.05) among the obtained values (from the file tip to actual apical foramen) and the hypothetical 1 mm value. Conclusion: The Joypex 5® electronic apex locator was found to be accurate and reliable for determination of an efficient and safe working length for endodontic treatment.

Effect of pre-flaring and file size on the accuracy of two electronic apex locators

OBJECTIVE: This ex vivo study evaluated the effect of pre-flaring and file size on the accuracy of the Root ZX and Novapex electronic apex locators (EALs). MATERIAL AND METHODS: The actual working length (WL) was set 1 mm short of the apical foramen in the palatal root canals of 24 extracted maxillary molars. The teeth were embedded in an alginate mold, and two examiners performed the electronic measurements using #10, #15, and #20 K-files. The files were inserted into the root canals until the "0.0" or "APEX" signals were observed on the LED or display screens for the Novapex and Root ZX, respectively, retracting to the 1.0 mark. The measurements were repeated after the preflaring using the S1 and SX Pro-Taper instruments. Two measurements were performed for each condition and the means were used. Intra-class correlation coefficients (ICCs) were calculated to verify the intra- and inter-examiner agreement. The mean differences between the WL and electronic length values were analyzed by the three-way ANOVA test (p<0.05). RESULTS: ICCs were high (>0.8) and the results demonstrated a similar accuracy for both EALs (p>0.05). Statistically significant accurate measurements were verified in the pre-flared canals, except for the Novapex using a #20 K-file. CONCLUSIONS: The tested EALs showed acceptable accuracy, whereas the pre-flaring procedure revealed a more significant effect than the used file size.

In vivo accuracy of conventional and digital radiographic methods in confirming root canal working length determination by Root ZX

OBJECTIVES: To compare, in vivo, the accuracy of conventional and digital radiographic methods in determining root canal working length. MATERIAL AND METHODS: Twenty-five maxillary incisor or canine teeth from 22 patients were used in this study. Considering the preoperative radiographs as the baseline, a 25 K file was inserted into the root canal to the point where the Root ZX electronic apex locator indicated the APEX measurement in the screen. From this measurement, 1 mm was subtracted for positioning the file. The radiographic measurements were made using a digital sensor (Digora 1.51) or conventional type-E films, size 2, following the paralleling technique, to determine the distance of the file tip and the radiographic apex. RESULTS: The Student "t" test indicated mean distances of 1.11 mm to conventional and 1.20 mm for the digital method and indicated a significant statistical difference (p<0.05). CONCLUSIONS: The conventional radiographic method was found to be superior to the digital one in determining the working length of the root canal.

Influence of pulp condition on the accuracy of an electronic foramen locator in posterior teeth: an in vivo study

The aim of this study was to assess, in vivo, the accuracy of the NovApex® electronic foramen locator in determining working length (WL) in vital and necrotic posterior teeth. The NovApex®was used in 144 canals: 35 teeth with vital pulps (68 canals) and 42 teeth with necrotic pulps (76 canals). WL was measured with the NovApex® locator and confirmed using the radiographic method. Differences between electronic and radiographic measurements ranging between 0.0 and 0.4 millimeters were classified as acceptable; differences equal to or greater than 0.5 millimeter were considered unacceptable. Pearson's chi-square test was used to assess the influence of pulp condition on the accuracy of NovApex®(a = 0.05). Regardless of pulp condition, differences between electronic and radiographic WL measurements were acceptable in 73.61% of the canals. No statistically significant differences in accuracy were observed when comparing vital and necrotic canals (p > 0.05). There were 38 unacceptable measurements. In none of these cases was the file tip located beyond the radiographic apex; in 32, it was located short of the NovApex® measurement. Pulp condition had no significant effect on the accuracy of NovApex®.

Ex vivo accuracy of three electronic apex locators using different apical file sizes

This study evaluated the accuracy of three electronic apex locators (Root ZX, Novapex, and Justy II) in root canal length determinations using different apical file sizes, considering the apical constriction (AC) and the major foramen (MF) as anatomic references. The diameter of the apical foramina of 40 single-rooted teeth was determined by direct visual measurement and the master apical file was established. Electronic measurements were then performed using 3 instruments: the selected master apical file (adjusted file), one size smaller (intermediate file), and two sizes smaller (misfit file). The distances from the tip of files fixed in the canals to the MF and to the AC were measured digitally. Precision at AC and at MF for the misfit, intermediate and adjusted apical files was as follows: 80%/88%/83% and 78%/83%/95% (Root ZX); 80%/85%/80% and 68%/73%/73% (Novapex); and 78%/80%/78% and 65%/78%/70% (Justy II). Considering the mean discrepancies, statistically significant differences were found only for the adjusted file at MF, with Root ZX presenting the best results at MF. The chi-square test showed significant differences between the acceptable measurements at AC and at MF for the Justy II and Novapex (± 0.5 mm) regardless of file adjustment. Under the conditions of the present study, all devices provided acceptable electronic measurements regardless of file adjustment, except for Root ZX which had its performance improved significantly when the precisely fit apical file was used. Justy II and Novapex provided electronic measurements nearest to the AC.

Este estudo avaliou a precisão de três localizadores eletrônicos foraminais (Root ZX, Novapex e Justy II) nas determinações de odontometria utilizando limas com diferentes padrões de ajuste, considerando-se a constrição apical (CA) e do forame principal (FA) como referências anatômicas. O diâmetro dos forames apicais de 40 dentes unirradiculados foi previamente determinado por visualização direta e a lima compatível com o forame apical foi estabelecida. Medições eletrônicas foram realizadas utilizando 3 instrumentos diferentes: lima compatível com o forame apical (lima ajustada), lima um tamanho menor (lima intermediária), e lima dois tamanhos menores (lima desajustada). As distâncias da ponta dos instrumentos ao FA e a CA foram determinadas em software específico. A precisão na CA e no FA para os instrumentos desajustado, intermediário e ajustado foram: 80% / 88% / 83% e 78% / 83% / 95% (Root ZX); 80% / 85% / 80% e 68% / 73% / 73% (Novapex), e 78% / 80% / 78% e 65% / 78% / 70% (Justy II). Considerando os erros médios oferecidos pelos aparelhos, foi encontrada diferença estatística apenas nas determinações realizadas com os instrumentos adaptados tendo como referência o FA onde o Root ZX ofereceu os melhores resultados. O teste qui-quadrado apresentou diferenças significantes entre as determinações consideradas aceitáveis para a CA e o FA tanto para o Justy II quanto para o Novapex (± 0,5 mm), independente do ajuste do instrumento. Nas condições do presente estudo todos os dispositivos ofereceram medições aceitáveis independentemente do ajuste dos instrumentos; exceção feita apenas ao Root ZX, que teve seu desempenho melhorado quando uma lima ajustada foi utilizada. Os aparelhos Justy II e Novapex ofereceram determinações mais próximas à CA.

Radiographic versus electronic root canal working length determination.

Purpose: The aim of this ex vivo study was to compare the accuracy of radiographic and electronic root canal length determination methods, compared with actual root canal length obtained with stereomicroscope. Materials and Methods: Thirty extracted single-rooted permanent teeth were used for this study. After access preparation, actual length (AL) of the root canal were determined for each tooth by inserting a #15 file until the tip of the file was visible at the apical foramen under a stereomicroscope. The radiographic working length determination was determined with a digital radiographic system and for the electronic measurement all teeth were embedded in an alginate model to test apex locator in-vitro. Data was analyzed using the descriptive statistic and intraclass correlation coefficient. Results: No significant difference was found between the radiographic and electronic root canal working length determination (P>0.05). The percentage of electronic measurements within ±0.5 mm to the apical constriction was 93.34% and 90% for radiographic methods within ±0.5 mm of all cases compared with AL. Conclusions: The present ex vivo study showed that electronic root canal working length determination is not superior to radiographic methods. Both methods provided a good performance in determining the root canal working length.