RESUMEN
OBJECTIVE: The aim of the present study was to assess the diagnostic value of a laser scanner developed to determine the coordinates of clinical bracket points and to compare with the results of a coordinate measuring machine (CMM). METHODS: This diagnostic experimental study was conducted on maxillary and mandibular orthodontic study casts of 18 adults with normal Class I occlusion. First, the coordinates of the bracket points were measured on all casts by a CMM. Then, the three-dimensional coordinates (X, Y, Z) of the bracket points were measured on the same casts by a 3D laser scanner designed at Shahid Beheshti University, Tehran, Iran. The validity and reliability of each system were assessed by means of intraclass correlation coefficient (ICC) and Dahlberg's formula. RESULTS: The difference between the mean dimension and the actual value for the CMM was 0.0066 mm. (95% CI: 69.98340, 69.99140). The mean difference for the laser scanner was 0.107 ± 0.133 mm (95% CI: -0.002, 0.24). In each method, differences were not significant. The ICC comparing the two methods was 0.998 for the X coordinate, and 0.996 for the Y coordinate; the mean difference for coordinates recorded in the entire arch and for each tooth was 0.616 mm. CONCLUSION: The accuracy of clinical bracket point coordinates measured by the laser scanner was equal to that of CMM. The mean difference in measurements was within the range of operator errors.
Asunto(s)
Arco Dental/anatomía & histología , Imagenología Tridimensional/métodos , Rayos Láser , Imagen Óptica/métodos , Soportes Ortodóncicos , Adulto , Puntos Anatómicos de Referencia/anatomía & histología , Diente Premolar/anatomía & histología , Diente Canino/anatomía & histología , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Procesamiento de Imagen Asistido por Computador/estadística & datos numéricos , Imagenología Tridimensional/estadística & datos numéricos , Incisivo/anatomía & histología , Modelos Dentales/estadística & datos numéricos , Diente Molar/anatomía & histología , Imagen Óptica/estadística & datos numéricos , Soportes Ortodóncicos/estadística & datos numéricos , Reproducibilidad de los Resultados , Corona del Diente/anatomía & histologíaRESUMEN
OBJECTIVE: The aim of the present study was to assess the diagnostic value of a laser scanner developed to determine the coordinates of clinical bracket points and to compare with the results of a coordinate measuring machine (CMM). METHODS: This diagnostic experimental study was conducted on maxillary and mandibular orthodontic study casts of 18 adults with normal Class I occlusion. First, the coordinates of the bracket points were measured on all casts by a CMM. Then, the three-dimensional coordinates (X, Y, Z) of the bracket points were measured on the same casts by a 3D laser scanner designed at Shahid Beheshti University, Tehran, Iran. The validity and reliability of each system were assessed by means of intraclass correlation coefficient (ICC) and Dahlberg's formula. RESULTS: The difference between the mean dimension and the actual value for the CMM was 0.0066 mm. (95% CI: 69.98340, 69.99140). The mean difference for the laser scanner was 0.107 ± 0.133 mm (95% CI: -0.002, 0.24). In each method, differences were not significant. The ICC comparing the two methods was 0.998 for the X coordinate, and 0.996 for the Y coordinate; the mean difference for coordinates recorded in the entire arch and for each tooth was 0.616 mm. CONCLUSION: The accuracy of clinical bracket point coordinates measured by the laser scanner was equal to that of CMM. The mean difference in measurements was within the range of operator errors. .
OBJETIVO: o objetivo do presente estudo foi avaliar o valor diagnóstico de um scanner a laser desenvolvido para determinar as coordenadas dos pontos de colagem de braquetes, comparando seus resultados aos resultados obtidos com uma máquina de medição coordenada (MMC). MÉTODOS: esse estudo experimental diagnóstico foi conduzido com modelos ortodônticos obtidos a partir da arcada superior de 18 pacientes adultos, com oclusão normal de Classe I. Inicialmente, as coordenadas dos pontos de colagem de braquetes de todos os modelos foram mensuradas por uma MMC. Em seguida, as coordenadas tridimensionais (X, Y, Z) dos pontos foram mensuradas nos mesmos modelos por um scanner a laser 3D, desenvolvido na Universidade de Shahid Beheshti. A eficácia e confiabilidade dos dois sistemas foram avaliadas pelo Coeficiente de Correlação Intraclasse (CCI) e pela fórmula de Dahlberg. RESULTADOS: a diferença entre a média da dimensão mensurada pela MMC e o valor real obtido foi de 0,0066mm (IC 95%: 69,98340 - 69,99140). A diferença média para o scanner a laser foi de 0,107 ± 0,133 (95% IC: -0,002 - 0,24). Em cada método, as diferenças não foram significativas. Ao comparar os dois métodos, o CCI gerou um valor de 0,998 para a coordenada X e de 0,996 para a coordenada Y. A diferença média para as coordenadas registradas em cada dente da arcada foi de 0,616mm. CONCLUSÃO: a precisão das coordenadas do ponto de colagem dos braquetes foi a mesma no scanner a laser e na MMC. A diferença média entre as medições manteve-se dentro dos limites de erros operacionais. .