Identification of the Most Appropriate Site for the Cold Test in Molar Teeth / Identificación del sitio más apropiado para la prueba de frío en dientes molares

Abstract A test frequently used to complement endodontic diagnoses is the cold test; however, in the last 20 years, authors have reported incorrect results within pulp sensitivity tests. Specifically, a high frequency of false results in posterior teeth, were found. The aim of this study was to identify the most appropriate site for the cold test in molar teeth with a need for endodontic treatment, calculating predictive values, accuracy and reproducibility. A cross-sectional study was performed, evaluating 390 subjects. A total of 152 subjects of both genders from the ages of 15-65 years old participated. The ideal standard was established by direct pulp inspection, and the cold test agent used was 1,1,1,2-tetrafluoroethane. The patients were divided into four groups in relation to the molar tooth: (1) mandibular first molar, (2) mandibular second molar, (3) maxillary first molar, and (4) maxillary second molar. 169 teeth and 676 sites were studied. (a) The most appropriate sites for cold test were the middle third of the buccal surface and cervical third of the buccal surface in the mandibular molars with the following results: Middle third of the first molar: Accuracy 0.93, positive predictive value 0.90 and negative predictive value 0.96. Middle third of the second molar: Accuracy 0.93, positive predictive value 1.00 and negative predictive value 0.90. In relation to third cervical the results were: First molar: Accuracy 0.93, positive predictive value 0.89 and negative predictive value 0.97 y second molar: Accuracy 0.93, positive predictive value 1.00 and negative predictive value 0.90. (b) The highest reproducibility was observed in the middle third of the buccal surface with cervical third of the buccal surface in the mandibular second molar (1.00). The most appropriate site and reproducibility of the sites are auxiliary to complement endodontic diagnose with the cold test.

Resumen Una prueba frecuentemente utilizada para complementar los diagnósticos endodónticos es la prueba de frío. Sin embargo, en los últimos 20 años, los autores han reportado resultados incorrectos con las pruebas de sensibilidad pulpar. Específicamente, se ha observado una alta frecuencia de resultados falsos en dientes posteriores. El objetivo del estudio fue identificar el sitio más adecuado para la prueba de frío en dientes molares con necesidad de tratamiento endodóntico, calculando valores predictivos, exactitud y reproducibilidad. Se realizó un estudio transversal donde se evaluaron a 390 sujetos. 152 sujetos de ambos sexos de 15 a 65 años cumplieron con los criterios de inclusión. El estándar ideal que se utilizó en el estudio fue la inspección directa de pulpa en la cámara pulpar y la prueba de frío utilizada fue el 1,1,1,2-tetrafluoroetano. Los pacientes fueron divididos en cuatro grupos en relación al diente molar: (1) primer molar mandibular, (2) segundo molar mandibular, (3) primer molar maxilar, y (4) segundo molar maxilar. En el estudio se evaluaron 169 dientes con 676 sitios. (a) Los sitios más adecuados para la prueba de frío fueron el tercio medio y el tercio cervical de la superficie bucal en los molares mandibulares con los siguientes resultados: Tercio medio del primer molar: Exactitud 0.93, valor predictivo positivo 0.90 y valor predictivo negativo 0.96. Tercio medio del segundo molar: Exactitud 0.93, valor predictivo positivo 1.00 y valor predictivo negativo 0.90. En relación al tercio cervical los resultados fueron: Primer molar: Exactitud 0.93, valor predictivo positivo 0.89 y valor predictivo negativo 0,97 y segundo molar: Exactitud 0.93, valor predictivo positivo 1.00 y valor predictivo negativo 0.90. (b) La más alta reproducibilidad (1.00) se observó entre el tercio medio con el tercio cervical de la superficie bucal en el segundo molar inferior. El sitio más apropiado y la reproducibilidad de los sitios son auxiliares para complementar el diagnóstico endodóntico con la prueba de frío.

Resin luting materials: Tissue response in dog's teeth.

The aim of this study was to evaluate radiographically and histologically the pulpal and periapical response to self-adhesive (Rely X™ Unicem) and self-etching and self-curing (Multilink(®)) resin-based luting materials in deep cavities in dogs' teeth. Deep class V cavities (0.5-mm-thick dentin) were prepared in 60 canine premolars and the following materials were applied on cavity floor: Groups I/V-RelyX™ Unicem; Groups II/VI-Multilink(®); Groups III/VII-zinc phosphate cement (control) and; Groups IV/VIII-gutta-percha (control). Cavities were restored with silver amalgam. Animals were euthanized after 10 days (groups I-IV) and 90 days (groups V-VIII). Tooth/bone blocks were radiographed and processed for histopathological evaluation of pulp and periapical tissue response to the materials. All materials presented similar histopathological features and radiographic findings at both periods. The pulp tissue was intact. The apical and periapical regions and periodontal ligament thickness were normal. No inflammatory cells, resorption of mineralized tissue (dentin, cementum, and alveolar bone) or bacteria were observed. The lamina dura was intact and no areas of periapical bone rarefaction or internal/external root resorption were observed radiographically. It can be concluded that Rely X™ Unicem and Multilink(®) caused no adverse tissue reactions and may be indicated for cementation of indirect restorations in deep dentin cavities without pulp exposure.

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...

Continuous drip flow system to develop biofilm of E. faecalis under anaerobic conditions.

PURPOSE: To evaluate a structurally mature E. faecalis biofilm developed under anaerobic/dynamic conditions in an in vitro system. METHODS: An experimental device was developed using a continuous drip flow system designed to develop biofilm under anaerobic conditions. The inoculum was replaced every 24 hours with a fresh growth medium for up to 10 days to feed the system. Gram staining was done every 24 hours to control the microorganism purity. Biofilms developed under the system were evaluated under the scanning electron microscope (SEM). RESULTS: SEM micrographs demonstrated mushroom-shaped structures, corresponding to a mature E. faecalis biofilm. In the mature biofilm bacterial cells are totally encased in a polymeric extracellular matrix. CONCLUSIONS: The proposed in vitro system model provides an additional useful tool to study the biofilm concept in endodontic microbiology, allowing for a better understanding of persistent root canal infections.

Efficacy of the self-adjusting file system on cleaning and shaping oval canals: a microbiological and microscopic evaluation.

INTRODUCTION: The shaping ability of root canal instruments is determined by a complex interrelationship of parameters such as cross-sectional design and the ability to remove debris and the smear layer. The self-adjusting file (SAF) consists of a hollow, flexible instrument in the form of a compressible, thin-walled, pointed cylinder. The aim of this study was to compare the SAF with the ProTaper rotary file system, evaluating debris and smear layer removal and the presence of bacteria by using microbiological and scanning electron microscopy (SEM) evaluation. METHODS: Fifty maxillary premolars were inoculated with Enterococcus faecalis for 30 days and then randomly distributed into 2 groups. Group 1 was prepared with ProTaper rotary instruments and irrigated with 30-gauge side-vented needles. Group 2 was prepared by using the SAF system with continuous irrigation. Bacteriologic samples were taken before and after preparation. All samples were then longitudinally split and analyzed under scanning electron microscopy. The scoring was carried out by 3 blinded evaluators. RESULTS: In group 1, 40% of samples had negative cultures with postinstrumentation samples taken with paper points (S2a) and 45% with postinstrumentation dentin samples (S2b). In group 2, 20% of samples had negative cultures with S2a and 15% with S2b. Intragroup analyses evaluating the reduction in the number of colony-forming units (CFUs) from S1 to S2a and S2b demonstrated both preparation techniques were highly effective (P < .01). Further reduction of CFUs was observed when comparing S2a and S2b in group 1 (P < .05), whereas no difference was observed in group 2. Intergroup analysis demonstrated a statistically significant difference of CFUs at S2a and S2b (P < .05). SEM scores were consistent with the microbiology findings. CONCLUSIONS: The SAF system does not allow control of the apical enlargement, thus limiting the ability of the irrigants to achieve effective and predictable disinfection.

Direct pulp capping in primary molars with enamel matrix derivative: report of a case.

UNLABELLED: Enamel Matrix Derivative (EMD) is a rich amelogenin and amelin biomaterial that has been demonstrated to induce a reparative process similar to normal odontogenesis when placed in contact with pulp tissue. However its effects in pulp capping on primary teeth has not been previously reported. THE AIM of the present case report is to present the favorable clinical and radiographic findings of a primary molar treated with direct pulp capping (DPC) and using EMD as capping material in a 6-year-old girl. RESULTS: After 12 months, there was no sign or symptom indicative of treatment failure, such as pain, gingival swelling, sinus tract, sensitivity to percussion or palpation, abnormal mobility, widening of periodontal space, internal or external root resorption, or supporting bone or furcal area radiolucencies.

Efficacy of EMD versus calcium hydroxide in direct pulp capping of primary molars: a randomized controlled clinical trial.

OBJECTIVE: The aim was to compare the clinical and radiographic efficacy of enamel matrix derivative and self-hardening calcium hydroxide as direct pulp capping materials on decayed primary molars, with observation periods of 1, 6, and 12 months. STUDY DESIGN: A clinical, randomized, controlled trial was performed, following the "split-mouth" design. A total of 90 primary molars were treated. Assignation of materials and operative initial side were selected in a randomized manner. Five outcome variables were considered: internal dentin resorption, pain, gingival sinus tract, root external resorption, and pathologic mobility. The appearance of any of these signs or symptoms was considered to be a failure of treatment. RESULTS: Significant statistical or clinical differences were not found between the study groups. Two treatments were judged as failures, 1 per study group; both occurred during the first postoperative month. CONCLUSIONS: The technique used for direct pulp capping on primary molars in this study is recommended on the basis of the obtained clinical and radiographic results.

Bacterial quantification in teeth with apical periodontitis related to instrumentation and different intracanal medications: a randomized clinical trial.

The antibacterial efficacy of intracanal medication with calcium hydroxide [Ca(OH)2], 2% chlorhexidine gel (CHX), and a combination of both [Ca(OH)2/CHX] was assessed in teeth with chronic apical periodontitis. Thirty-three canals were instrumented, randomly divided into three groups, and medicated with either Ca(OH)2, CHX, or Ca(OH)2/CHX. Bacteriological samples obtained from the operative field and the root canals before (S1) and after instrumentation (S2) in the first treatment session, and after medication (S3) in the second session 1 week later, were assessed for bacterial growth, observed by turbidity and in agar plates, and viable colony-forming unit (CFU) counts. Bacterial growth and CFU counts decreased significantly from S1 to S2 (Mann-Whitney, p<0.05). Differences in growth and counts between S2 to S3 were not statistically significant for all three intracanal medication groups. It was concluded that the antibacterial efficacy of Ca(OH)2, CHX, and Ca(OH)2/CHX was comparable.

Comparación del hidróxido de calcio como medicamento intraconducto, utilizando vehículos viscosos y acuosos. Estudio "in vitro" / A comparison of calcium hydroxide as intracanal medicament, using aqueous and viscous vehicles. An in vitro study

El hidróxido de calcio (CaOH2) es un compuesto químico utilizado ampliamente en el tratamiento endodóntico como medicamento intraconducto, pero no existe un criterio que permita a los profesionales de esta área identificar y utilizar el vehículo idóneo para combinarlo, de ello depende la optimización de sus propiedades, entre otras: capacidad para inducir la formación de tejido duro, incidencia para causar oclusión intratubular, acción antibacteriana y capacidad de disolución tisular. Estas propiedades se fundamentan en la capacidad de disociación iónica que tiene el hidróxido de calcio en iones calcio e hidróxilo. La finalidad de este estudio fue analizar por espectrofotometría de absorción atómica y potenciometría el comportamiento del hidróxido de calcio con diferentes vehículos, debido a la relación que existe entre la disociación lenta y sostenida de este compuesto con su efecto como agente terapéutico en tratamientos de apicoformación, eliminación de microorganismos de conductos radiculares infectados con lesión periapical. Se encontró que de los cuatro vehículos estudiados: propilenglicol, polietilenglicol 400, glicerol y suero fisiológico a diferentes tiempos (24 h, 7, 15 y 30 días) el que mostró mejor comportamiento al combinarse con el CaOH2 fue el propilenglicol, presentando una liberación mayor de iones calcio de 580 ppm a los 7 días, seguido por el polietilenglicol con una liberación de 280 ppm, en tanto que el suero fisiológico presentó 270 ppm, finalmente el glicerol sólo liberó 16.6 ppm. Con respecto al valor de pH, se mantuvo en un rango de 12.07 a 12.78 durante los cuatro períodos del análisis