ABSTRACT
Objective To examine the method of least-square fitting for calibrating the palatal rugae boundary. Methods According to the distribution of the teeth, the feature points were selected; when they were fit, the boundary of the palatal rugae area was created, thereby constructing a mask. The mask was used to remove the part located outside the boundary and filter out the interference. Three samples were utilized for the ex-periments and analyses to come. Results To evaluate the quantitative results of the fitting curves, the correla-tion coefficients(r)of the samples and the relationship between the actual mean value and ideal mean value was obtained through six fitting processes. The differences between the actual mean and ideal mean were found to be significantly small (from 0.2857 to 2.5000) in the six fitting processes, with the range of r close to 1(from 0.9896 to 0.9995). Conclusion The effect of the cubic polynomial fitting method adopted in this study was stable.The proposed boundary calibration method can effectively locate the palatal rugae boundary and remove the interference area, further promoting the practice of forensic identification.
ABSTRACT
Age estimation plays a very important role in individual recognition in forensic dentistry. Morphological data of 3D pulp cavity of maxillary canines were acquired by oral and craniofacial CT scans. In accordance with inclusion criteria, CT data of 103 patients (51 males and 52 females) were collected at the Department of Radiology, Stomatological Hospital, Shanxi Medical University, China from September 2015 to August 2016. Mimics 17.0 software was used to measure pulp volume of maxillary canines and tooth volume, and to calculate the ratio of pulp volume/tooth volume. SPSS 16.0 software was utilized to analyze and establish database. Linear regression analysis was applied to process data and to establish a linear regression equation for individual age: Y=69.137-621.200 (pulp volume/tooth volume), R=0.544. Subjects were grouped according to gender, deriving the inferred function of male age: Y=64.333-468.811 (pulp volume/tooth volume), R=0.435; the inferred function of female age: Y=76.445-843.186 (pulp volume/tooth volume), R=0.691. The ratio of pulp volume to tooth volume can be used to infer individual age, and can provide a new method and pathway for individual recognition in forensic dentistry.
La estimación de la edad juega un papel importante en el reconocimiento individual en la odontología forense. Los datos morfológicos de la cavidad pulpar tridimensional de los caninos maxilares fueron adquiridos por tomografía computarizada oral y craneofacial. De acuerdo con los criterios de inclusión, se recolectaron datos de 103 pacientes (51 hombres y 52 mujeres) en el Departamento de Radiología del Hospital de Estomatología de la Universidad de Medicina de Shanxi, desde septiembre de 2015 hasta agosto de 2016. Se utilizó el software Mimics 17.0 para medir el volumen de pulpa de los caninos maxilares y el volumen del diente, además, se calculó la relación entre el volumen de la pulpa y el volumen del diente. Se utilizó el software SPSS 16.0 para analizar y establecer las bases de datos. El análisis de regresión lineal se aplicó a los datos del proceso y para establecer la edad individual se aplicó una ecuación de regresión lineal: Y = 69.137-621.200 (volumen de la pulpa / volumen del diente), R = 0.544. Los sujetos se agruparon según el sexo, derivando la función inferida de la edad masculina: Y = 64.333-468.811 (volumen de la pulpa / volumen del diente), R = 0.435; La función inferida de la edad de la mujer: Y = 76.445-843.186 (volumen de la pulpa / volumen del diente), R = 0.691. La relación entre el volumen de la pulpa y el volumen del diente puede usarse para inferir la edad individual y puede proporcionar un nuevo método y forma para el reconocimiento individual en la odontología forense.
Subject(s)
Humans , Male , Female , Age Determination by Skeleton , Cuspid/anatomy & histology , Dental Pulp Cavity/anatomy & histology , Forensic Dentistry , Tomography, X-Ray Computed , Linear Models , Cuspid/diagnostic imaging , Dental Pulp Cavity/diagnostic imagingABSTRACT
Objective To explore the clinical application value of three-dimensional reconstruction of maxillary canine pulp volume /tooth volume (PV/TV)in individual gender determination.Methods There were 103 patients (51 males and 52 females) with CBCT imaging data from September 2015 to August 2016, Shanxi Medical University, department of radiology, Mimics 17.0 software was used to measure pulp volume of maxillary canines and tooth volume, and to calculate the ratio of pulp volume/tooth volume.The data were processed by SPSS16.0 statistical software and Fisher discriminant method. The gender determination function was obtained and Cross -Validated method for performance evaluation. Results When gender determination was determined by tooth volume (TV) and pulp volume/tooth volume (PV / TV) as the study index, the gender discriminant function was Y=0.009(TV)+28.896(PV/TV) - 6.962, Cross-validated method for the effect of evaluation, to determine the compliance rate: 51 males, the correct rate of 64.7%;52 female, the correct rate of 78.8%. Conclusion The tooth volume (TV) and pulp volume/tooth volume (PV/TV)can be used as a research indicator of gender inference, it provides a new method and avenue for the gender determination in forensic medicine.