Forensic age diagnostics of living individuals in criminal proceedings

Age estimations of living individuals are increasingly important in criminal matters. If doubts arise regarding the age of a person suspected of a criminal offense, forensic age estimation is prompted by the need to ascertain whether the person concerned has reached the age of criminal responsibility and whether general criminal law in force for older juveniles or adults is to be applied. According to the recommendations of the Arbeitsgemeinschaft für Forensische Altersdiagnostik (study group for forensic age diagnostics), age estimates in criminal proceedings should be based on the general physical examination, the X-ray examination of the hand and the odontological examination by a dentist, including dental status and orthopantomogram. In order to improve diagnostic reliability, these methods should always be used in combination, ensuring that each part is performed by forensically trained and experienced experts of the relevant disciplines. In order to demonstrate that the proband has reached the age of 21, an additional X-ray examination or CT scan of the clavicles is recommended. Future research projects should assess the variation for a combination of the above methods, quantify the impact of socio-economic status and ethnicity on the examined development systems and review the suitability of non-ionizing imaging methods of age estimation.     

Tooth eruption in Reeves' muntjac (Muntiacus reevesi) and its use as a method of age estimation (Mammalia: Cervidae)

The sequence of tooth eruption and replacement in Reeves' muntjac was determined from captive animals of known age. Pronounced sexual dimorphism is shown by the permanent upper canine which in the male is large, tusk-like and is used as a weapon. The upper canine was the first deciduous tooth to be replaced in males, at approximately 21 weeks of age, compared with 53–57 weeks in the female. The permanent mandibular teeth erupted in the order: molars, first and second incisors, premolars, third incisor and canine. The maxillary teeth erupted in the order: first molar, canine (in male), second and third molars, canine (in female), premolars. The full complement of 34 functional permanent teeth was attained by 83–92 weeks of age.     

Studies on the progress of third-molar mineralisation in a Black African population.

The forensic determination of the age of living people has become increasingly important in recent years. With regard to the relevant age group, the radiographic assessment of third-molar mineralisation is of particular importance. So far, the influence of geographic origin on the mineralisation rate has been insufficiently analysed. The paper is based on a total of 595 conventional orthopantomograms of 474 male and 121 female Black Africans aged between 10 and 26 years for whom dates of birth were known. The mineralisation status of third molars was evaluated based on Demirjian's classification of stages [Demirjian et al., 1973. A new system of dental age assessment. Hum. Biol. 45, 221-227]. This study presents the means and standard deviations, median values and the lower and upper quartiles separately for both sexes for the mineralisation stages D-H. Statistically significant differences between the upper and lower jaws were observed in males examined with regard to their attaining the stage F. Mandibular teeth developed 0.8 years earlier than maxillary teeth. Significant sex-specific differences were found with regard to the age at which tooth 38 reached the stage G. In females, tooth 38 reached stage G 1.5 years earlier than in males. In comparison to White probands, the Black African sample showed a tendency to achieve the mineralisation stages earlier. We would recommend using population-specific standards for age determination purposes.     

Dental reductions and dental caries

Although first permanent molar hypoconulid absence, third molar agenesis, and small tooth size are all part of the evolutionary trend of dental reduction, each bears a different relationship to dental caries. Caries prevalence in the maxillary and mandibular permanent first molars of the Burlington Research Centre serial experimental group at age 16 years was less in the children whose first molars were missing the hypoconulid. Conversely, caries prevalence in mandibular first molars was greater in the children who had agenesis of third molars. The extraction of first molars due to caries was more frequent in children with agenesis of third molars, less frequent in those with absence of hypoconulids of the first molars and unrelated to tooth size. Caries prevalence was less in small teeth, and occurred least in the small mandibular first molars with four cusps. Whereas this is in harmony with the hypothesis that evolutionary dental reductions resulted from the pressure of caries, the increased prevalence of caries and extractions coinciding with third molar agenesis does not support this view. In addition, agenesis of hypoconulids and agenesis of third molars were related to changes in structures unrelated to caries.     

Formation of the permanent dentition in Arikara Indians: timing differences that affect dental age assessments

This report concerns one problem encountered with application of American white dental formation standards to age assessment of sub-adults of archaeological context. Dental ages for eight mandibular permanent teeth and maxillary central and lateral incisors of Arikara Indian immature skeletons were determined according to degree of crown or root mineralization. Ages assigned to the various teeth of the same individual were compared. They showed similarities as well as patterned differences. First premolar, second premolar, and mandibular incisor ages closely approximated one another. In relation to this complex, dental ages for maxillary incisors and mandibular second molars were older by 0.5 to 1.1 years. Developmental ages assigned to individuals on the basis of third molars showed relative advancement by more than 2 years. The systematic occurrence of these observations reflects more than just individual variability; it shows the presence of population differences in tooth-formation timing. Timing differences complicate assessment of dental ages needed for growth or demographic studies.     

Oral health related to demographic features in Bosnian children aged six

The main aim of this paper is to present epidemiological indicators of oral health among six-year olds in Bosnia and Herzegovina (BH) and to analyze values of dmft index and dental treatment needs in order to identify differences in parts of the country. Another aim is to identify the needs from the public oral health care system in Bosnia and Herzegovina related to early permanent dentition by analyzing the condition of first permanent molars (FPM) as an indicator of oral health of permanent dentition. Survey was carried out in 2004 in 8 cantons of the Federation of BH (FBH) and in the Republic of Srpska (RS). Final sample included 560 participants aged six (mean 6.2, SD +/- 0.87). One dental team clinically examined all participants according to WHO methodology and criteria. The parameters used were: dmft index, DMFT index of first permanent molars (FPM), presence of sealants and treatment needs. A questionnaire about oral health habits had been administered. Dmft was 6.71 in that the d-component constituted the major part of the index. DMFT index of FPM was 0.61 (SD +/- 1.08). Percentage of caries free participants aged 6 was 6.8%. Average number of FPM with fissure sealants in BH was 0.25 (SD +/- 0.78). Significant demographic differences in dmft index, DMFT FPM and treatment needs were identified. Most participants (48.5%) had their first dental visit between the ages of five and seven. National oral health goal for Bosnia and Herzegovina should be to develop and implement disease prevention programs based on education of both parents and dental practitioners. It is necessary to improve access to dental care and shift focus from curative to preventive procedures. It is also necessary to set real goals for improvement of oral health which can be achieved within a desired time frame, as well as to precisely define measures to be taken.     

Relationships between age and dental attrition in Australian aboriginals

Tooth wear scores (ratios of exposed dentin to total crown area) were calculated from dental casts of Australian Aboriginal subjects of known age from three populations. Linear regression equations relating attrition scores to age were derived. The slope of the regression line reflects the rate of tooth wear, and the intercept is related to the timing of first exposure of dentin. Differences in morphology between anterior and posterior teeth are reflected in a linear relationship between attrition scores and age for anterior teeth but a logarithmic relationship for posterior teeth. Correlations between age and attrition range from less than 0.40 for third molars (where differences in the eruption and occlusion of the teeth resulted in different patterns of wear) to greater than 0.80 for the premolars and first molars. Because of the generally high correlations between age and attrition, it is possible to estimate age from the extent of tooth wear with confidence limits of the order of +/- 10 years.     

Dental caries in disabled children

The aim of the study was to evaluate oral health conditions and dental caries status in disabled and healthy children. Two groups of randomly selected children 3-17 years old were examined. The first group comprised 80 children with disabilities (cerebral palsy, mental retardation, Down syndrome, autism and hearing-speaking disorders) and the second (control) group included 80 healthy children. Examined children were selected from several institutions which take care of disabled persons, kindergardens and four elementary schools. Clinical examination was performed by using a mirror and a probe and revealed the presence of dental caries, missing (extracted) and filled teeth. All clinically detected cavitations were registered as dental caries. The degree of oral hygiene was evaluated according to the OHI-S index values, which was determined by marking the plaque with 1% eozine solution. The values of OHI-S index ranged from 3.8-4.53 in disabled children and 2.73-2.84 in healthy children. In disabled children, the average dft values were 3.42 in deciduous teeth and 5.24 in mixed dentition. In healthy children, the average dft values were 1.43 in deciduous teeth and 5.1 in mixed dentition. The average DMFT index in disabled children was 1.41 for mixed and 6.39 for permanent dentitions. In healthy children, the average DMFT values were 1.23 in mixed and 4.76 in permanent dentitions. In general, the results revealed significantly poor level of oral hygiene and quite high level of caries prevalence in both disabled and healthy children, accentuating the need to reorganize preventive care measurements and improve dental care, particularly in disabled children in Croatia.     

Tooth loss and tooth retention in a multitribal group of Bantu-speaking South African blacks: A study on 500 dry mandibles

Tooth loss and tooth retention in adult South African Bantu-speaking Negroes were studied from data derived from 500 dry mandibles. The tribe, sex, and stated age of the specimens were available. Mandibles were equally distributed over the third to seventh decade of life. The presence of dental units was recorded and analysed within and between decade age groups. The mandibles carried a total of 5,459 dental units. Between the third and fourth decades of life and between the sixth and seventh decades, the reduction of the frequency of dental units was mild and statistically not significant. It was, however, severe and significant between the fourth and fifth, and the fifth and sixth decades. In the third-decade group, most teeth were found in the anterior region with a tendency to diminish in number posteriorly. After the third decade there was a definite persistence of first premolars and canines with significant tendency toward loss of teeth anterior and posterior to them. Only the incisors and third molars showed significant reduction in number from the third to the fourth decade. The reduction of all teeth was statistically significant later, until the sixth decade of life. Although there was loss of teeth from the sixth to the seventh decade, it was not significant for any of the homologous dental units. There is a possibility that some dietary differences existed between the older subjects (50–70 years old) and the younger ones (20–49 years old) which may have had some influence on the results.     

Increasing human tooth length between birth and 5.4 years

Most previous studies of tooth development have used fractional stages of tooth formation to construct growth standards suitable for aging juvenile skeletal material. A simple alternative for determining dental age is to measure tooth length throughout development. In this study, data on tooth length development are presented from 63 individuals of known age at death, between birth and 5.4 years, from an archeological population recovered from the crypt of Christ Church, Spitalfields, London. Isolated developing teeth (304 deciduous, 269 permanent) were measured in millimeters and plotted against individual age. Regression equations to estimate age from a given tooth length, are presented for each deciduous maxillary and mandibular tooth type and for permanent maxillary and mandibular incisors, canines, and first permanent molars. Data on the earliest age of root completion of deciduous teeth and initial mineralization and crown completion of some permanent teeth in this sample are given, as well as the average crown height and total tooth length from a small number of unworn teeth. This method provides an easy, quantitative and objective measure of dental formation appropriate for use by archeologists and anthropologists. © 1993 Wiley-Liss, Inc.     

Oral health among institutionalised elderly in Zagreb, Croatia

Objective: A survey of dental health status was conducted in the institutionalised elderly in Zagreb, Croatia in order to assess the dental and oral health of the elderly population. Participants: In 139 institutionalised elderly from a single nursing home in Zagreb, dental and oral status was registered according to World Health Organization criteria. There were 108 (77.7%) female and 31 (22.3%) male subjects aged 58–99 years. Results: The results showed that 45.3% of the interviewed persons were totally edentulous in both jaws. A significant increase in prevalence of edentulousness with the increasing age was recorded. The mean decayed, missing and filled teeth number was 27. The average number of teeth with caries was 1.03 per person, the number of the teeth extracted was 6.9 per person and teeth with fillings 0.74 per person. The average number of teeth with root caries was 0.17. Approximately 9 teeth per person were in need of treatment. Filled teeth were found 25.9% of subjects and decayed teeth in 30.9%. The mean number of remaining sound teeth, decayed teeth and residual roots in the elderly decreased with increasing age. Complete periodontal treatment was required in 5.8% of the participants and no significant differences between genders in periodontal status could be noticed. Conclusion: The results of this study suggest poor dental health in this group of the institutionalised elderly and the necessity of improving and implementing some special features in the dental health services programs for the institutionalised elderly.     

Measurements of tooth wear among Australian Aborigines: I. Serial loss of the enamel crown

The dental casts made from Aboriginal children during the course of a longitudinal growth study in Central Australia provided material for analyzing tooth wear under known environmental conditions. The wear facets produced on the occlusal surfaces were clearly preserved on the dental stone casts and recorded the progress of enamel attrition from ages 6 to 18. These casts were photographed and traced by electronic planimetric methods that automatically recorded the location and size of wear facets on the first and second permanent molars. These areas of worn tooth surface were compared to the total tooth surface. The worn surface was regressed on age to calculate wear rates of each tooth. Discriminant analyses were also performed to determine the significance of dental attrition differences between the sexes at each age group. The total wear on each tooth was highly correlated with age as expected but females wore their teeth at a significantly higher rate than males. The mandibular molars wore more rapidly than maxillary teeth in both sexes. The discriminant analysis successfully grouped 91% of the cases according to age and sex. Pattern of wear, the location, and size of wear facets also differed between age groups and sex. The questions of why there is a difference between male and female wear or why there is greater wear on one arch or arch region have no ready answers. The differing rates and pattern of dental wear do suggest that arch shape and growth rates may be the answer though it has yet to be tested. However, the occlusal surface wear is useful for age estimation in a population and provides a record of shifting masticatory forces during growth.     

Oral health of the elderly living in residential homes in Slovenia

doi: 10.1111/j.1741‐2358.2011.00497.x
Oral health of the elderly living in residential homes in Slovenia Objectives:  To evaluate oral health status of the elderly, living in eight randomly selected residential homes for senior citizens across the country. Background: The percentage of the elderly is growing worldwide. With ageing, risks of various oral diseases, including dental caries and periodontal disease, are growing. Methods: Altogether 296 elderly people (88 men, 208 women) of average age 79.89 ± 7.4 years were questioned about their medical condition and oral health practice and examined orally. Evaluation of clinical examination was carried out by DMFT, plaque index ( 10 ) and Community Periodontal Index of Treatment Need (CPITN). Results: Of 296 participants, 106 (35.8%) were edentulous, 95 (32.1%) had one to nine teeth and 95 persons (32.1%) had 10 or more teeth. The average number of teeth in an individual was small: 6.76 ± 7.47. The average number of teeth with caries lesions was 3.59 ± 4.70, filled teeth 1.94 ± 3.63 and teeth without caries or fillings 1.19 ± 2.41. The average DMFT value was 30.75. In 69.5% of participants, dental plaque was visible with the naked eye. Of 171 subjects, in whom CPITN index was appraised, 81.9% would need oral hygiene education, 56.7% would need scaling and root planning and 21.6% would need periodontal surgical treatment. Conclusions: The results of this study indicate poor oral health of the elderly living in residential homes situated in different towns in Slovenia. It is of utmost importance to highlight the necessity of improving oral health care of this population.     

Twins and the paradox of dental-age estimations: A caution for researchers and clinicians

The biological age difference among twins is frequently an issue in studies of genetic influence on various dental features, particularly dental development. The timing of dental development is a crucial issue also for many clinicians and researchers. The aim of this study was therefore to verify within groups of twins how dental development differs, by applying Demirjian's method, Mincer's charts of development of third molars and two of Cameriere's methods for dental age estimation, which are among the most popular methods both in the clinical and the forensic scenario. The sample consisted of 64 twin pairs: 21 monozygotic, 30 dizygotic same-sex and 13 dizygotic opposite-sex with an age range between 5.8 and 22.6 years. Dental age was determined from radiographs using the mentioned methods. Results showed that dental age of monozygotic twins is not identical even if they share all their genes. The mean intra-pair difference of monozygotic pairs was low and similar to the difference in dizygotic same-sex twins; the maximum difference between monozygotic twins, however, was surprisingly large (nearly two years). This should lead to some circumspection in the interpretation of systematic estimations of dental age both in the clinical and forensic scenario.     

Prenatal dental development in the black howler monkey (Alouatta caraya)

Prenatal dental development was investigated in 19 black howler monkey fetuses that ranged in crown-rump length from 84 mm to 170.5 mm. During this period of fetal development, all of the deciduous teeth and the first permanent molars were found to pass through various stages of crown and root formation. The deciduous incisors, canines, and first molars each calcified from a single calcification center. The second deciduous molars each calcified from two separate calcification centers. And, the third deciduous and first permanent molars each calcified from four separate calcification centers. The morphogenetic events involved in the establishment of the molar crown patterns were found to differ markedly from those of their counterparts among catarrhine primates. In all cases, however, the calcification sequence was found to be directly related to the morphology of the developing crown.     

Developmental stage of the dentition and speech sound production in a series of first-grade schoolchildren.

This study was undertaken to investigate the effect of developmental stage of the dentition on speech sound production in children with and without articulatory speech disorders. In the whole sample, there were 281 subjects, mean age 7.5 years (SD 0.4). The stage of the eruption of the permanent incisors was calculated as the percentage height of each tooth of the mean crown height of the corresponding tooth in a group of 252 young adults. Eruptional stage of the first permanent molars was classified into three categories. Articulatory disorders were diagnosed by one experienced speech therapist and phoniatrician using the Remes Articulation Test [Remes, 1975] for the Finnish language. The results showed a wide interindividual variation in developmental stage of the dentition in a group of 7-year-old children with a tendency of the first permanent molars but not the incisors to erupt earlier in girls than in boys. Boys had a higher frequency of misarticulations estimated to need treatment than did girls. The present results indicate that during eruption of permanent teeth it is more important to draw attention to symmetrical eruption and to individual timing pattern rather than to the mean values of tooth eruption in subjects of the same age. The findings also suggest a decreasing risk of faulty speech sound production with advancing eruption of some permanent teeth still present in 7-year-old children.     

Structural Morphology of Molars in Large Mammalian Herbivores: Enamel Content Varies between Tooth Positions

The distribution of dental tissues in mammalian herbivores can be very different from taxon to taxon. While grazers tend to have more elaborated and complexly folded enamel ridges, browsers have less complex enamel ridges which can even be so far reduced that they are completely lost. The gradient in relative enamel content and complexity of structures has so far not been addressed within a single species. However, several studies have noted tooth position specific wear rates in small mammals (rabbits, guinea pigs) which may be related to individual tooth morphology. We investigate whether differentiated enamel content by tooth position is also to be found in large herbivores. We use CT-scanning techniques to quantify relative enamel content in upper and lower molar teeth of 21 large herbivorous mammal species. By using a broad approach and including both perissodactyls and artiodactyls, we address phylogenetic intraspecific differences in relative enamel content. We find that enamel is highly unevenly distributed among molars (upper M1, M2, M3 and lower m1, m2, m3) in most taxa and that relative enamel content is independent of phylogeny. Overall, relative enamel content increases along the molar tooth row and is significantly higher in lower molars compared to upper molars. We relate this differential enamel content to prolonged mineralisation in the posterior tooth positions and suggest a compensatory function of m3 and M3 for functional losses of anterior teeth.     

Association between Dental Caries and Down Syndrome: A Systematic Review and Meta-Analysis

Scientific evidence of susceptibility to dental caries in the population with Down Syndrome (DS) is limited and conflicting, making it difficult to establish firm conclusions. The aim of this systematic review and meta-analysis was to obtain scientific evidence of the possible association between dental caries and individuals with DS, compared to individuals without DS (control). An electronic search of five databases was performed, with no language or publication date restrictions. The studies were selected by two independent reviewers (Kappa = 0.83). The systematic review included 13 studies, while eight studies were included in the meta-analysis. The studies are presumably all at risk of bias given their observational character. Two of these evaluated the presence or absence of caries in permanent and deciduous teeth, and six evaluated the mean DMFT index in permanent teeth. Combined odds ratios (OR), standard difference, standard error and a 95% confidence interval (CI) were obtained. The vast majority of the studies found that individuals from control groups had more carious lesions or caries experience than those with DS. The results were statistically significant in seven studies (p<0.05). Meta-analysis of two studies revealed that individuals with DS had a lower dental caries than those in the control group (OR = 0.36; 95% CI = 0.22–0.57). In six studies, individuals with DS had a significantly lower mean DMFT index than individuals from the control group (Sd = -0.18; SE = 0.09; 95% CI = -0.35–-0.02). The quality of the studies varied and in general had a high risk of bias. Scientific evidence suggests that individuals with DS have fewer dental caries than individuals without DS.     

Dental treatment strategies in a 40-year-old patient with cleidocranial dysplasia

Oral anomalies and dental treatment in a patient with cleidocranial dysplasia (referred to the dental clinic at the age of 40 years) are presented. Five supernumerary teeth were found in the patient: three in the maxilla in the area of molars and two in the mandibula in the area of premolars. Therapy included surgical exposure of impacted teeth in combination with removal of supernumerary teeth.     

昆明市儿童恒牙萌出时间及恒牙萌出与生长发育关系的调查研究

本文报道了昆明市8148例儿童恒牙（第三磨牙除外）萌出时间的横断面调查，对恒牙萌出与年龄、身高、体重和月经初潮的关系进行了探讨。经相关分析，恒牙萌出数与年龄高度相关，与身高和体重低度相关，并建立了由年龄、身高或体重推算萌牙数的回归方程。还发现恒牙萌出与青少年性成熟也有一定的联系。提示恒牙萌出也能反映儿童的生长发育状况，故可作为衡量儿童生长发育的一项指标。