RESUMEN
Traumatic dental injuries (TDIs) of permanent teeth occur frequently in children and young adults. Crown fractures and luxations are the most commonly occurring of all dental injuries. Proper diagnosis, treatment planning and follow up are important for improving a favorable outcome. Guidelines should assist dentists and patients in decision making and for providing the best care effectively and efficiently. The International Association of Dental Traumatology (IADT) has developed a consensus statement after a review of the dental literature and group discussions. Experienced researchers and clinicians from various specialties were included in the group. In cases where the data did not appear conclusive, recommendations were based on the consensus opinion of the IADT board members. The guidelines represent the best current evidence based on literature search and professional opinion. The primary goal of these guidelines is to delineate an approach for the immediate or urgent care of TDIs. In this first article, the IADT Guidelines for management of fractures and luxations of permanent teeth will be presented. The Hebrew Edition is part of the IADT global effort to provide accessibility to these guidelines worldwide.
Asunto(s)
Avulsión de Diente/terapia , Corona del Diente/lesiones , Fracturas de los Dientes/terapia , Niño , Dentición Permanente , Humanos , Israel , Lenguaje , Avulsión de Diente/diagnóstico , Fracturas de los Dientes/diagnóstico , Adulto JovenRESUMEN
Avulsion of permanent teeth is one of the most serious dental injuries, and a prompt and correct emergency management is very important for the prognosis. The International Association of Dental Traumatology (IADT) has developed a consensus statement after a review of the dental literature and group discussions. Experienced researchers and clinicians from various specialties were included in the task group. The guidelines represent the current best evidence and practice based on literature research and professionals' opinion. In cases where the data did not appear conclusive, recommendations were based on the consensus opinion or majority decision of the task group. Finally, the IADT board members were giving their opinion and approval. The primary goal of these guidelines is to delineate an approach for the immediate or urgent care of avulsed permanent teeth. The Hebrew Edition is part of the IADT global effort to provide a worldwide accessibility to these guidelines. This scond part of the guidelines will focus on avulsion of permanent teeth.
Asunto(s)
Tratamiento de Urgencia/métodos , Avulsión de Diente/terapia , Dentición Permanente , Humanos , Israel , Lenguaje , Avulsión de Diente/diagnósticoRESUMEN
Traumatic injuries to the primary dentition present special problems and the management is often different as compared with the permanent dentition. The International Association of Dental Traumatology (IADT) has developed a consensus statement after a review of the dental literature and group discussions. Experienced researchers and clinicians from various specialities were included in the task group. In cases where the data did not appear conclusive, recommendations were based on the consensus opinion or majority decision of the task group. Finally, the IADT board members were giving their opinion and approval. The primary goal of these guidelines is to delineate an approach for the immediate or urgent care for management of primary teeth injuries. The IADT cannot and does not guarantee favorable outcomes from strict adherence to the guidelines, but believe that their application can maximize the chances of a positive outcome. The Hebrew Edition is part of the IADT global effort to provide a worldwide accessibility to these guidelines. This third part will discuss injuries in the primary dentition.
Asunto(s)
Traumatismos de los Dientes/terapia , Diente Primario/lesiones , Tratamiento de Urgencia/métodos , Humanos , Israel , Lenguaje , Traumatismos de los Dientes/diagnósticoRESUMEN
PURPOSE: The purpose of this study was (a) to evaluate the incidence of paraaortic lymph node metastasis from adenocarcinoma of the endometrium clinically limited to the uterus (1971 FIGO Stages I and II) and (b) to report the 5 year disease-free survival of patients with histologically documented paraaortic lymph node metastasis from endometrial adenocarcinoma clinically limited to the uterus treated on two separate protocols. METHODS AND MATERIALS: From June 1979 to June 1990, 109 patients underwent staging paraaortic lymphadenectomy or paraaortic lymph node biopsy at the time of total abdominal hysterectomy and bilateral salpingo-oophorectomy for adenocarcinoma of the endometrium clinically limited to the uterus. Patients with histologically documented paraaortic lymph node metastasis were treated on two protocols: (a) pelvic radiation (5,040 cGy) plus progestins or (b) pelvic radiation therapy (5,040 cGy) plus paraaortic radiation (4,500 cGy). RESULTS: Paraaortic lymph node metastases was primarily associated with grade 3 tumors (34.4%) and deep myometrial invasion (42%) and was present in 17.4% (19) of 109 patients. None of the women treated with pelvic radiation therapy and progestins survived five years disease-free. In contrast, the 5 year disease-free survival was 27% for patients treated by pelvic and paraaortic radiation. CONCLUSIONS: Since all patients with macroscopic metastases to the paraaortic lymph nodes developed recurrent cancer and only a small percentage of those with microscopic metastases to the paraaortic lymph nodes survived disease-free at 5 years, improved survival for patients with paraaortic lymph node metastases will necessitate the addition of effective cytotoxic chemotherapy to pelvic and paraaortic radiation.
Asunto(s)
Adenocarcinoma/cirugía , Neoplasias Endometriales/cirugía , Neoplasias Uterinas/cirugía , Adenocarcinoma/epidemiología , Adenocarcinoma/radioterapia , Adulto , Anciano , Anciano de 80 o más Años , Terapia Combinada , Neoplasias Endometriales/epidemiología , Neoplasias Endometriales/radioterapia , Femenino , Humanos , Metástasis Linfática , Persona de Mediana Edad , Progestinas/uso terapéutico , Radioterapia de Alta Energía , Neoplasias Uterinas/epidemiología , Neoplasias Uterinas/radioterapiaRESUMEN
Human immunodeficiency virus (HIV) infections are being seen with greater regularity by the obstetrician-gynecologist. Acquired immunodeficiency syndrome (AIDS), the extreme of the spectrum of HIV infections, is associated with Pneumocystis carinii infection in more than half of newly diagnosed cases. Four cases of AIDS and P carinii pneumonia complicating pregnancy have been reported in the literature, and all have caused maternal death. We report a case in which the mother survived. Treatment was similar to that used in the other reported cases except that steroids were added. A limited number of patients with AIDS and P carinii infection have been treated with trimethopterim-sulfamethoxazole and steroids, with good results. Steroids should be considered for cases in which other efforts are failing.
Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/complicaciones , Neumonía por Pneumocystis/complicaciones , Complicaciones Infecciosas del Embarazo , Adulto , Quimioterapia Combinada , Eritromicina/uso terapéutico , Femenino , Humanos , Metilprednisolona/uso terapéutico , Neumonía por Pneumocystis/tratamiento farmacológico , Embarazo , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Combinación Trimetoprim y Sulfametoxazol/uso terapéuticoRESUMEN
Within the stated limits of cell fine structure preservation and within the observed anatomical limits specified in the Results and Discussion sections, a freeze-substitution method using an ethylene glycol-Hank's solution eutectic mixture with a glutaraldehyde additive can be used to effectively prepare undecalcified human dentin for electron microscopy. The ultrastructual appearance of the odontoblast cell body and the odontoblastic process subjected to freeze-substitution differs from that seen with conventional chemical fixation. Artifacts produced by freeze-substitution differ in appearance and frequency of occurrence from those produced by glutaraldehyde-osmium tetroxide sequential double fixation. The cellular component of dentin shows greater structural preservation of protein when it is subjected to freeze-substitution that when it is prepared by conventional chemical fixation. The absence of ice crystal defects in the odontoblastic process in calcified dentin and the presence of ice crystal defects in the odontoblast cell body suggest that intracellular water in the odontoblastic process in the calcified dentin may exist in a more highly structured state than intracellular water in the odontoblast cell body. If intracellular water exists in a more highly structured state in the odontoblastic process of the calcified dentin than in the cell body, the ratio of protein molecules to cytoplasmic volume may be greater in the odontoblastic process than in the cell body. After glutaraldehyde-osmium tetroxide sequential double fixation, the use of graded alcohol dehydration obtained cell fine structure preservation and artifact control superior to that obtained by use of ethylene glycol cryodehydration. Further refinements of the freeze-substitution technique, as it applies to the preparation of undecalcified human dentin, are necessary to increase the amount of cellular preservation, to decrease the number of ice crystal artifacts, and to improve the overall quality of cell fine structure preservation.
Asunto(s)
Dentina/ultraestructura , Liofilización/métodos , Técnicas Histológicas , Microscopía Electrónica , Adolescente , Adulto , Membrana Celular/ultraestructura , Humanos , Odontoblastos/ultraestructura , Organoides/ultraestructura , Unión Proteica , Agua/metabolismoRESUMEN
Temporal effects in simulataneous masking were studied by measuring the reduction in the amount of masking produced by a gated masker when that masker was preceded by a 400-ms noise (the precursor) that was usually spectrally identical to the masker. The signal frequency (fs) was 1.0 or 4.0 kHz. Experiment 1 revealed a temporal effect only when there was a spectral notch (centered at fs) in the masker and precursor. For a relative notchwidth of 0.4 fs, the temporal effect was larger at 4.0 than at 1.0 kHz. In experiment 2. where the masker and precursor both consisted of two bands of noise separated by a spectral notch of 0.4 fs, the size of the temporal effect remained essentially constant as the bandwidth of these noise bands increased from 0.2-0.8 kHz. The results from experiment 3 indicated that the temporal effect was largest when the level fo the precursor was equal to the level of the masker. Finally, the results from experiment 4 suggested that the temporal effect may depend upon the frequency region below as well as above fs, but that the frequency region above fs is probably more important.
Asunto(s)
Estimulación Acústica , Umbral Auditivo , Adolescente , Adulto , Humanos , Enmascaramiento PerceptualRESUMEN
A Phase I/II study was initiated to evaluate complications of orthovoltage intraoperative radiation therapy utilized in the treatment of patients with incompletely resected recurrent gynecologic malignancies. There were no osseous, vascular, neurologic, or ureteral complications. Of the 23 treated patients, 2 patients (8.7%) had complications outside the treated area. Survival of patients treated with intraoperative radiation therapy was highest among patients treated to a field of < or = 3 cm in greatest diameter and a tumor thickness of < or = 1 mm. A subgroup of patients (5) with microscopically positive margins following total pelvic exenteration demonstrated an absence of recurrence in the treated field. The role of intraoperative radiation therapy (IORT) in the treatment of recurrent and incompletely resectable gynecologic malignancies remains investigational.
Asunto(s)
Neoplasias de los Genitales Femeninos/radioterapia , Recurrencia Local de Neoplasia/radioterapia , Braquiterapia , Terapia Combinada , Femenino , Neoplasias de los Genitales Femeninos/patología , Neoplasias de los Genitales Femeninos/cirugía , Humanos , Periodo Intraoperatorio , Metástasis de la Neoplasia , Dosificación Radioterapéutica , Análisis de SupervivenciaRESUMEN
The purpose of this study was to determine whether heat sterilization adversely effects the torsional properties of rotary nickel-titanium files, making them more prone to fracture under torsional stress. Nine hundred sizes 2 through 10 Profile Series 29.04 taper files were divided into groups of 10 files each and sterilized 0, 1, 5, or 10 times in the steam autoclave, Statim autoclave, or dry heat sterilizer. Then, they were subjected to torsional testing in a Torquemeter Memocouple. Complete data were collected for sizes 2 through 7, but not for sizes 8 through 10 because their torque resistance exceeded the testing limits of the Torquemeter Memocouple. A one-way analysis of variance was used to compare all experimental groups in sizes 2 through 7 with their unsterilized controls (p < 0.05). Fifty-four comparisons were made for torsional strength and 54 for rotational flexibility. Ten significant changes occurred for torsional strength and 10 for rotational flexibility. Eight of 10 changes in torsional strength were increases. Fifty-two of 54 (96.3%) comparisons for torsional strength and 47 of 54 (87%) for rotational flexibility showed a significant increase or no change. Therefore, heat sterilization of rotary nickel-titanium files up to 10 times does not increase the likelihood of instrument fracture.
Asunto(s)
Aleaciones Dentales/química , Níquel/química , Tratamiento del Conducto Radicular/instrumentación , Esterilización/métodos , Titanio/química , Análisis de Varianza , Análisis de Falla de Equipo/métodos , Análisis de Falla de Equipo/estadística & datos numéricos , Calor , Distribución Aleatoria , Rotación , Vapor , TorqueRESUMEN
The purpose of this study was to investigate the quantity of apical debris produced in vitro using two hand and two rotary instrumentation techniques. Sixty minimally curved, mature human mandibular premolars with single canals were divided into 4 groups of 15 teeth each and prepared using step-back instrumentation with K-files, balanced force with Flex-R files, Lightspeed nickel-titanium instruments, or .04 taper ProFile Series 29 rotary nickel-titanium files. Debris extruded through the apical foramen during instrumentation was collected on preweighed filters. The mean weight of extruded debris for each group was statistically analyzed using a Kruskal Wallis one-way analysis of variance and a Mann-Whitney U rank sum tested. Although all instrumentation techniques produced apically extruded debris, step-back instrumentation produced significantly more debris than the other methods (p < 0.0001). There was no difference between balanced force hand instrumentation and the two rotary nickel-titanium instrumentation methods (p > 0.05). Hand or engine-driven instrumentation that uses rotation seems to reduce significantly the amount of debris extruded apically when compared with a push-pull (filing) technique. Decreased apical extrusion of debris has strong implications for a decreased incidence of postoperative inflammation and pain.
Asunto(s)
Filtración Dental , Preparación del Conducto Radicular/métodos , Ápice del Diente , Diente Premolar , Aleaciones Dentales , Humanos , Técnicas In Vitro , Mandíbula , Níquel , Preparación del Conducto Radicular/instrumentación , TitanioRESUMEN
The purpose of this in vitro study was to compare the quality of the seal in canals prepared in a standardized manner and obturated with a .06 or a .02 tapered gutta-percha master cone using lateral condensation. Forty-four extracted human anterior teeth with single, straight canals were divided into two experimental groups of 20 teeth each and two control groups of 2 teeth each. The teeth were instrumented with Series 29 Profile .06 tapered rotary nickel-titanium files to a master apical file of 0.46 mm. Teeth in group 1 were obturated with a .02 tapered master gutta-percha cone and Roth 801 sealer using lateral condensation. Teeth in group 2 were obturated similarly, except a .06 tapered master gutta-percha cone was used. The depth of spreader penetration was recorded in millimeters. Positive control teeth were instrumented but not filled. Negative control teeth were instrumented, obturated, and externally sealed. The teeth were placed into a coronal leakage apparatus that contained an upper and lower reservoir of trypticase soy broth separated by the tooth. A 24-h growth of Proteus vulgaris in 0.25 ml of trypticase soy broth was placed in the coronal reservoir every 7 days for 70 days and incubated at 37 degrees C. Student's t test was used to determine whether there was a difference in spreader penetration between the groups, and a Fisher's exact test was used to determine whether there was a difference in bacterial leakage. The positive and negative controls validated the testing model. When a .02 tapered master cone was used, the spreader penetrated significantly closer to working length than when a .06 tapered master cone was used (p < 0.05). The difference between the groups in the number of samples that demonstrated complete bacterial penetration was not significant (p > 0.05).
Asunto(s)
Filtración Dental/prevención & control , Gutapercha , Obturación del Conducto Radicular/métodos , Distribución de Chi-Cuadrado , Humanos , Incisivo , Preparación del Conducto Radicular/métodosRESUMEN
The purpose of this study was to compare an objective to a subjective method of tooth shade evaluation using the SP78 sphere spectrophotometer and human visual analysis. Twenty extracted fully developed human maxillary teeth had their L* values (lightness) read by the SP78 on day 1 and then again on day 14. Using a blind method, five human evaluators then attempted to match shade tabs from a six-tab experimental Vita shade guide to the same teeth on days 1 and 14. The SP78 L* values read for each tooth were evaluated for a match between those obtained on day 1 and those read on day 14. The results of human evaluation of tooth shade were compared among the evaluators and then between themselves over time. Finally, the ability of human evaluators to match tooth shade was compared with the results obtained with the SP78. The SP78 reproduced L* readings within the standard error of the machine (< or = 1.0) in 16 of 20 (80%) teeth. In contrast, interevaluator agreement expressed as majority agreement (3, 4, or 5 of 5 evaluators agreeing) was only 10 of 20 (50%) teeth on day 1 and 13 of 20 (65%) teeth on day 14. Intraevaluator agreement over the experimental period ranged from 20 to 60%. The results of this study confirm that human evaluation of tooth shade is unreliable and that the SP78 sphere spectrophotometer can provide a more predictable and accurate method of evaluating tooth shade in vitro. This finding opens up a new avenue of investigation for testing the effectiveness of materials and techniques in bleaching discolored teeth.
Asunto(s)
Color/normas , Decoloración de Dientes/diagnóstico , Diente/química , Estudios de Evaluación como Asunto , Humanos , Variaciones Dependientes del Observador , Estándares de Referencia , Reproducibilidad de los Resultados , Espectrofotometría/instrumentación , Blanqueamiento de DientesRESUMEN
The purpose of this study was to evaluate objectively in vitro the effectiveness of bleaching artificially discolored teeth with or without the smear layer present using sodium perborate mixed with sterile water or 35% hydrogen peroxide (H2O2). Seventy fully developed maxillary anterior teeth were artificially stained with human hemoglobin and separated into one control and four experimental groups. After the smear layer was removed on half the experimental teeth and left intact on the other half, all of the teeth were bleached intracoronally with sodium perborate and 35% H2O2 or sodium perborate plus water. The bleaching agents were applied twice over a 6-day period. The changes in tooth shade were objectively analyzed using a SP78 sphere spectrophotometer at 1, 30, and 60 days postbleaching. The presence or absence of the smear layer did not significantly influence the outcome of bleaching (p > 0.05). The teeth bleached with sodium perborate and 35% H2O2 were significantly lighter than the teeth bleached with sodium perborate and sterile water (p < 0.0001) at each experimental period. Based on the findings of this study, it is not advantageous to remove the smear layer before intracoronal bleaching.
Asunto(s)
Capa de Barro Dentinario , Blanqueamiento de Dientes/métodos , Decoloración de Dientes/terapia , Boratos , Estudios de Evaluación como Asunto , Humanos , Peróxido de Hidrógeno , Incisivo , Espectrofotometría/instrumentaciónRESUMEN
The solid plastic carrier in the Thermafil obturation system must be removed to facilitate retreatment. The purpose of this study was to compare the efficacy and time required to retreat canals obturated with Thermafil with plastic carriers using a new technique based on the System B HeatSource or a solvent. Fifty-two extracted human mandibular premolars with single canals were instrumented and then obturated with Thermafil with plastic carriers. After 2 wk storage at 22 degrees C and 100% humidity, they were randomly divided into 2 groups of 26 teeth each. Group 1 teeth were retreated using chloroform and hand files, whereas teeth in group 2 were retreated with a new technique using the System B HeatSource. The end point of retreatment was defined as complete removal of the plastic carrier. The time required for retreatment was recorded. Then, the apical 5 mm segment of each root was sectioned horizontally at 1 mm intervals and each section digitally imaged. The total area of the canal and the area of the canal occupied by gutta-percha and sealer were measured using NIH image software. Data were analyzed using an unpaired t test. The mean time for retrieval of the plastic carrier was significantly less for the System B technique (1.8 min) than for the solvent technique (3.6 min) (p < 0.001). The difference between the two groups in the amount of filling material (carrier, gutta-percha, and sealer) removed was not significant (p > 0.05).
Asunto(s)
Preparación del Conducto Radicular/métodos , Diente Premolar , Remoción de Dispositivos/métodos , Gutapercha , Calor , Humanos , Procesamiento de Imagen Asistido por Computador , Distribución Aleatoria , Retratamiento , SolventesRESUMEN
The purpose of this study was to evaluate the effectiveness of three pigmented glass ionomer cements used as intraorifice barriers to prevent coronal microleakage. One hundred ten extracted mandibular human premolars were divided into four experimental groups of 25 teeth each and two control groups of 5 teeth each. The experimental teeth were instrumented and obturated using thermoplasticized gutta-percha and AH26 sealer. Group 1 teeth received no further treatment. Teeth in groups 2 through 4 had 1 of 3 pigmented glass ionomers (Vitrebond, GC America, and Ketac-Bond) placed as an intraorifice barrier. Positive control teeth were instrumented but not obturated. The negative control teeth were instrumented, obturated, and externally sealed with epoxy resin. The coronal 3 mm of each root was sealed into the lumen of an 18-mm segment of latex surgical tubing. After the apparatus was sterilized, 2.0 ml of a 24 h growth of Proteus vulgaris in trypticase soy broth (TSB) was placed in the coronal reservoir of the tooth. The inoculated apparatus was placed into a presterilized test tube containing 1.5 ml of TSB and incubated for 90 days at 37 degrees C. The TSB in the lower reservoir was observed daily for turbidity, which would indicate leakage along the full length of the obturated root canal. To determine if differences in microbial leakage occurred among the four experimental groups, Pearson's chi 2 and Fisher's exact tests were performed. The confidence level was set at 95%. The positive and negative controls validated the microbial testing method. The teeth without an intraorifice barrier leaked significantly more than teeth with Vitrebond intraorifice barriers (p < 0.05). The difference in leakage among the experimental glass ionomer barriers was not significant (p > 0.05).
Asunto(s)
Filtración Dental/prevención & control , Cementos de Ionómero Vítreo , Materiales de Obturación del Conducto Radicular , Obturación del Conducto Radicular/métodos , Diente no Vital , Distribución de Chi-Cuadrado , Humanos , Estadísticas no ParamétricasRESUMEN
The purpose of this study was to determine the incidence of vertical root fractures in the mesial roots of extracted human mandibular molars that were endodontically prepared by hand or ultrasonic instrumentation and obturated with laterally condensed gutta-percha and sealer using finger and hand spreaders. One-hundred twenty mesiofacial canals were prepared by hand or ultrasonic instrumentation. After placing the teeth in a simulated alveolus, they were obturated by laterally condensing gutta-percha and sealer with B-finger or D11T hand spreaders. Teeth were obturated using forces in the range of 1 to 3 kg or 4.5 to 7.5 kg. Three teeth obturated with the D11T hand spreader using 7.0 to 7.3 kg of force demonstrated vertical root fractures. The results suggest that in vitro the range of forces reported as most commonly used by endodontists to laterally condense gutta-percha (1.0 to 3.0 kg) and those of a higher magnitude up to 4.9 kg are safe and will not result in vertical root fractures of mesial roots of mandibular molars.
Asunto(s)
Cavidad Pulpar/patología , Tratamiento del Conducto Radicular/métodos , Fracturas de los Dientes/epidemiología , Terapia por Ultrasonido/instrumentación , Humanos , Incidencia , Diente Molar , Tratamiento del Conducto Radicular/instrumentación , Fracturas de los Dientes/etiologíaRESUMEN
This study compared the effectiveness of hand and ultrasonic instrumentation for removing a standardized inoculum of pigmented Serratia marcescens from the root canal system of premolars in dogs. Forty-four premolars from nine beagle dogs were divided into two experimental groups of 20 and 24 teeth, respectively. The experimental teeth were inoculated with approximately 10 colony-forming units of S. marcescens. After the bacterial were allowed to colonize for 1 wk, the experimental teeth were instrumented with either hand instruments or the Cavi-Endo device. The teeth were extracted, crushed, and assayed for recoverable colony-forming units of S. marcescens. Statistical comparisons of the ratio of inoculated to recovered colony-forming untis were made. The results indicated that the difference between the positive controls and the experimental groups was significant. There was no significant difference between the two instrumentation groups.
Asunto(s)
Cavidad Pulpar/microbiología , Tratamiento del Conducto Radicular/métodos , Terapia por Ultrasonido/instrumentación , Animales , Perros , Tratamiento del Conducto Radicular/instrumentaciónRESUMEN
This study compared the apical seal produced by four obturation techniques. Sixty-four extracted human teeth were prepared and obturated using lateral condensation of gutta-percha that was either unmodified or was dipped in chloroform, eucalyptol, or eucapercha paste. After storage in normal saline and 0.02% azide solution at 37 degrees C for 200 days, the teeth were immersed in India ink for 48 h. The most coronal extent of leakage of India ink into the canal was then determined. Significantly more apical leakage occurred in the eucapercha group than in the other three groups. All other comparisons were equivalent. The results suggest that modification of the gutta-percha master cone with solvent does not improve the apical seal in vitro. If modification is desired, then dipping the master cone in either eucalyptol or chloroform produces an apical seal superior to that achieved with eucapercha.
Asunto(s)
Ciclohexanoles , Filtración Dental/prevención & control , Gutapercha , Monoterpenos , Obturación del Conducto Radicular/métodos , Terpenos , Cloroformo , Combinación de Medicamentos , Eucaliptol , Humanos , Mentol/análogos & derivados , Materiales de Obturación del Conducto RadicularRESUMEN
This study compared apical transportation produced in curved (45- to 60-degree) molar canals instrumented with two MM-3000 Sonic Air test files (Rispi-Sonic and Trio-Sonic) with apical transportation from instrumentation with conventional K-type files. Seventy-five extracted human permanent mandibular molars were equally divided into three groups. Results showed that 92 (61%) of 150 measurements demonstrated no transportation, and only 7 (5%) had transportation between 0.25 and 0.5 mm. Most of the transportation was 0.25 mm or less, and no file produced transportation greater than 0.5 mm in a buccolingual or mesiodistal direction. Statistical analysis (chi-square test and analysis of variance) showed no significant difference (p greater than 0.05) in the amount of apical transportation in canals prepared with the Kerr K-type, Rispi-Sonic, or Trio-Sonic files.
Asunto(s)
Tratamiento del Conducto Radicular/instrumentación , Cavidad Pulpar/anatomía & histología , Humanos , Tratamiento del Conducto Radicular/métodosRESUMEN
The purpose of this study was to evaluate new or previously identified solvents for effectiveness in dissolving gutta-percha. The solubility of a standardized weight of gutta-percha was tested in 5-ml quantities of 32 solvents. Ten samples of 30 solvents were tested at both 22 and 37 degrees C for 15 min. If the gutta-percha samples dissolved within 15 min, the times were recorded and statistically analyzed. There was no significant difference (p greater than 0.05, one-way analysis of variance and Scheffe's test) between dissolving times of chloroform and trichloroethylene at 22 and 37 degrees C. At 22 degrees C, three solvents dissolved the gutta-percha sample, whereas at 37 degrees C, nine solvents dissolved the gutta-percha. At 37 degrees C, halothane (Fluothane) was twice as effective as cineole and demonstrated many favorable working qualities. An important finding from the experimentation with halothane was the discovery of a potential obturating material, which was termed "halopercha".