H M Liversidge1, K Peariasamy2, M O Folayan3, A O Adeniyi4, P I Ngom5, Y Mikami6, Y Shimada7, K Kuroe8, I F Tvete9, S I Kvaal10. 1. Institute of Dentistry, Queen Mary University of London, Barts and The London School of Medicine and Dentistry, London, United Kingdom. 2. Department of Paediatric Dentistry, Sungai Buloh Hospital, Selangor, Malaysia. 3. Department of Child Dental Health, Obafemi Awolowo University, Osogbo, Nigeria. 4. Department of Preventive Dentistry, Lagos State University Teaching Hospital, Lagos, Nigeria. 5. Department of Dentistry, University Cheikh Anta Diop, Dakar, Senegal. 6. Community and Global Health, Graduate School of Medicine, University of Tokyo, Japan. 7. Department of Pediatric Dentistry, Showa University, School of Dentistry, Tokyo, Japan. 8. Kuroe Orthodontic Practice, Kagoshima, Japan. 9. Norwegian Computing Center, Oslo, Norway. 10. Institute of Clinical Dentistry, University of Oslo, Oslo, Norway.
Abstract
BACKGROUND: The nature of differences in the timing of tooth formation between ethnic groups is important when estimating age. AIM: To calculate age of transition of the mandibular third (M3) molar tooth stages from archived dental radiographs from sub-Saharan Africa, Malaysia, Japan and two groups from London UK (Whites and Bangladeshi). MATERIALS AND METHODS: The number of radiographs was 4555 (2028 males, 2527 females) with an age range 10-25 years. The left M3 was staged into Moorrees stages. A probit model was fitted to calculate mean ages for transitions between stages for males and females and each ethnic group separately. The estimated age distributions given each M3 stage was calculated. To assess differences in timing of M3 between ethnic groups, three models were proposed: a separate model for each ethnic group, a joint model and a third model combining some aspects across groups. The best model fit was tested using Bayesian and Akaikes information criteria (BIC and AIC) and log likelihood ratio test. RESULTS: Differences in mean ages of M3 root stages were found between ethnic groups, however all groups showed large standard deviation values. The AIC and log likelihood ratio test indicated that a separate model for each ethnic group was best. Small differences were also noted between timing of M3 between males and females, with the exception of the Malaysian group. These findings suggests that features of a reference data set (wide age range and uniform age distribution) and a Bayesian statistical approach are more important than population specific convenience samples to estimate age of an individual using M3. CONCLUSION: Some group differences were evident in M3 timing, however, this has some impact on the confidence interval of estimated age in females and little impact in males because of the large variation in age.
BACKGROUND: The nature of differences in the timing of tooth formation between ethnic groups is important when estimating age. AIM: To calculate age of transition of the mandibular third (M3) molar tooth stages from archived dental radiographs from sub-Saharan Africa, Malaysia, Japan and two groups from London UK (Whites and Bangladeshi). MATERIALS AND METHODS: The number of radiographs was 4555 (2028 males, 2527 females) with an age range 10-25 years. The left M3 was staged into Moorrees stages. A probit model was fitted to calculate mean ages for transitions between stages for males and females and each ethnic group separately. The estimated age distributions given each M3 stage was calculated. To assess differences in timing of M3 between ethnic groups, three models were proposed: a separate model for each ethnic group, a joint model and a third model combining some aspects across groups. The best model fit was tested using Bayesian and Akaikes information criteria (BIC and AIC) and log likelihood ratio test. RESULTS: Differences in mean ages of M3 root stages were found between ethnic groups, however all groups showed large standard deviation values. The AIC and log likelihood ratio test indicated that a separate model for each ethnic group was best. Small differences were also noted between timing of M3 between males and females, with the exception of the Malaysian group. These findings suggests that features of a reference data set (wide age range and uniform age distribution) and a Bayesian statistical approach are more important than population specific convenience samples to estimate age of an individual using M3. CONCLUSION: Some group differences were evident in M3 timing, however, this has some impact on the confidence interval of estimated age in females and little impact in males because of the large variation in age.
Authors: P W Thevissen; A Alqerban; J Asaumi; F Kahveci; J Kaur; Y K Kim; P Pittayapat; M Van Vlierberghe; Y Zhang; S Fieuws; G Willems Journal: Forensic Sci Int Date: 2010-05-18 Impact factor: 2.395
Authors: A Schmeling; C Grundmann; A Fuhrmann; H-J Kaatsch; B Knell; F Ramsthaler; W Reisinger; T Riepert; S Ritz-Timme; F W Rösing; K Rötzscher; G Geserick Journal: Int J Legal Med Date: 2008-06-12 Impact factor: 2.686
Authors: M-D Marrero-Ramos; L López-Urquía; A Suárez-Soto; A Sánchez-Villegas; M Vicente-Barrero Journal: Med Oral Patol Oral Cir Bucal Date: 2020-05-01