ABSTRACT
The purpose of this study was to evaluate the efficiency of ProFile, GT, ProTaper, Race and K3 rotary instruments compared with hand K-files for removal of gutta-percha during retreatment. Sixty mandibular premolars were instrumented with GT rotary files and filled by thermomechanical compaction of gutta-percha and AH Plus sealer. The teeth are randomly divided into 6 groups of 10 specimens each. The roots were split longitudinally, digital images were created using a flatbed scanner, and the areas with remaining filling material were demarcated using Image Tool 1.21 software. The results indicate that GT left significantly less (p<0.05) remaining filling material (1.18 ± 1.47) than hand (3.70 ± 3.16) and Hero instruments (2.99 ± 2.58). There was no statistically significant difference (p<0.05) among the others techniques: ProFile (1.99 ± 2.66), ProTaper (2.00 ± 1.99) and K3 (2.71 ± 2.87) when compared with GT. In conclusion, GT, ProFile, ProTaper and K3 were more effective in removing gutta-percha than manual and Hero instruments.
O propósito deste estudo foi avaliar a eficiência dos instrumentos rotatórios ProFile, GT, ProTaper, Race e K3 comparados com limas K para a remoção do material obturador durante o retratamento. Sessenta pré-molares inferiores foram instrumentados com o sistema rotatório GT e obturados usando a técnica de compactação termomecânica de guta-percha com cimento AH Plus. Os dentes foram divididos aleatoriamente em seis grupos de dez espécimes cada. As raízes foram seccionadas longitudinalmente, imagens digitais foram criadas através de um scanner, e as áreas de remanescentes de material foram medidas usando o programa Image Tool 1.21. Os resultados indicaram que o GT deixou significantemente menos material remanescente (1,18 ± 1,47) do que os instrumentos manuais (3,70 ± 3,16) e os instrumentos Hero (2,99 ± 2,58) (p<0,05). Não houve diferença estatisticamente significante entre as outras técnicas ProFile (1,99 ± 2,66), ProTaper (2,00 ± 1,99) e K3 (2,71 ± 2,87) quando comparadas com o GT. Como conclusão, GT, ProFile, ProTaper e K3 foram revelados como mais efetivos em remover a guta-percha do que os instrumentos manuais e os instrumentos Hero.
Subject(s)
Humans , Dental Alloys/chemistry , Nickel/chemistry , Root Canal Preparation/instrumentation , Titanium/chemistry , Bicuspid/pathology , Calcium Sulfate/chemistry , Dental Cements/chemistry , Dental Pulp Cavity/pathology , Efficiency , Equipment Design , Epoxy Resins/chemistry , Gutta-Percha/chemistry , Image Processing, Computer-Assisted/methods , Polyvinyls/chemistry , Retreatment , Rotation , Root Canal Filling Materials/chemistry , Root Canal Preparation/methods , Software , Surface Properties , Zinc Oxide/chemistryABSTRACT
OBJECTIVES: The aim of this study was to evaluate cases of dental trauma treated at the specialized center of Pontifical Catholic University of Paraná, Curitiba, Brazil, during a period of 2 years. MATERIAL AND METHODS: A total of 647 patients were evaluated and treated between 2003 and 2005. Data obtained from each patient were tabulated and analyzed as to gender, age, etiology, time elapsed after the injury, diagnosis (type of trauma), and affected teeth. RESULTS: The results revealed that male individuals aged 7 to 13 years presented the highest prevalence of injury, and falling was the main causal factor. In most cases, the time elapsed between the accident and the first care ranged from 4 to 24 h. A total of 1,747 teeth were affected, with higher incidence of concussion/subluxation and coronal fracture, followed by lateral luxation and avulsion. The permanent maxillary central incisors were the most commonly affected teeth. CONCLUSION: The frequency and causes of dentoalveolar trauma should be investigated for identification of risk groups, treatment demands and costs in order to allow for the establishment of effective preventive measures that can reduce the treatment duration and costs for both patients and oral health services.