Orthodontic Treatment: Real Risk for Dental Age Estimation in Adults?

Dental age estimation becomes a challenge once the root formation is concluded. In living adults, one dental age indicator is the formation of secondary dentine, also associated with orthodontic treatment as well as root shortening. The aim of this study was to establish whether these secondary effects of orthodontic treatment could generate a statistically significant difference in dental age estimations when using Kvaal's method. The study sample included 34 pairs of pre‐ and postorthodontic panoramic radiographs, from different individuals with exactly the same age and sex distribution. Females 65%, median age 17.5 years, and males 35%, median age 22.5 years, were included. After data collection, dental age was estimated per tooth using formulae previously published. The risk of obtaining over‐estimation of age was calculated. (RR = 1.007). The changes caused by orthodontic treatment do not have any significant effect on age estimation when Kvaal et al.'s method is applied on panoramic radiographs.     

Pneumatic spaces of the zygomatic arch (zygomatic air cell defect) on pantomograms--an aid for age determination and identification

The analysis of panoramic radiographs of the jaws for forensic purposes is well established. The dental findings on the radiographs give valuable information concerning the identity and possible age. Panoramic radiographs also depict the zygomatic arches. Pneumatized spaces of the temporal bone's zygomatic arch process are asymptomatic variations, entitled "zygomatic air cell defect" (ZACD). Data on ZACD prevalence might support the current forensic-odontologic practice in the fields of identification and age assessment. The authors analyzed 6 studies subjected to evaluate ZACD on panoramic radiographs. The out-patients were subjected to systematic radiography prior to treatment planning in specialized dental or maxillofacial surgery clinics. The age of the 7870 patients varied between 6 and 97 years. ZACD was found in 169 patients (prevalence: 2.32%; female: 56.12%, male: 43.9%). Most ZACD were unilateral (70%). In these studies no ZACD occurred in children younger than 7 years of age. There was no statistically significant difference concerning ZACD prevalence in the sub-groups of children aged 9 to 13 vs. 14 to 17 years. This review demonstrates the prevalence of ZACD on orthopantomograms. The prevalence of this finding in the investigated children does not differ from the prevalences reported for adults, and is low in general. The presence of ZACD in persons might be valuable for the identification of humans or human remains and for age estimation in addition to other physical and dental findings.     

Radiopaque Images Resembling Obturated Root Canals,

The practice of endodontics, while not as common as today, was performed during the WWII era. Some of the materials used to fill canals during this time period include gutta‐percha, calcium hydroxide, gold foil, and silver points. In this case study, fissures and fractures were present on the exposed root surfaces of the dental remains. Radiographs of the dental remains revealed canal systems similar to those obturated with a paste or semi‐solid material. The root surface defects appear to be the access point for the radiopaque material. As demonstrated in the case presentation, the radiographic image suggestive of a treated canal may easily mislead the analyst. The analyst should be suspicious of a radiopaque artifact if no evidence of access is apparent and fissures/fractures are present on the root surfaces. The defects in the tooth structure may possibly be explained by the exposure to a wet or damp environment.     

Medical devices; performance standard for diagnostic x-ray systems; amendment. Department of Health and Human Services (HHS), Public Health Service (PHS), Food and Drug Administration (FDA). Final rule

The Food and Drug Administration (FDA) is issuing a final rule that amends the diagnostic x-ray systems performance standard for dental panoramic systems and mammography systems. This rule exempts panoramic dental x-ray units from the requirement that they be manufactured with exposure timers that automatically reset to zero upon premature termination of an exposure. Removing the automatic timer reset requirement will not compromise the quality of the radiographic image and will protect patients from being subject to unnecessary radiation due to repeat radiographs. This action also is intended to align the performance standard for mammography systems with the equipment requirements issued under the Mammography Quality Standards Act of 1992 (the MQSA).     

The application of Kvaal's dental age calculation technique on panoramic dental radiographs

INTRODUCTION: Literature reports on a method for dental age calculation which is based only on radiological measurements on periapical dental radiographs: the relationship between chronological age and the two-dimensional dental pulpal size was analysed by means of multiple regression analyses. The purpose of the present study was to evaluate whether this approach could be feasible and could lead to statistically sound results with adequate repeatability when applied on panoramic radiographs. MATERIALS AND METHODS: One hundred and ninety seven panoramic radiographs were collected at random from patients of whom the age ranged from 19 to 75 years. According to the reported technique, six teeth were selected on the panoramic radiograph: in the maxilla the central and lateral incisor and second bicuspid, and in the mandibula the lateral incisor, cuspid and first bicuspid. The same exclusion criteria as in the original paper were respected. Statistical analysis was carried out in order to spot significant differences between the chronological age and the calculated age. RESULTS: When the age was calculated based on measurements of all six teeth or of all three mandibular teeth, no significant differences were found between the real age and the calculated one. In all other instances using the individual teeth separately or using all three maxillary teeth statistical analysis revealed significant differences. CONCLUSION: There appears to be no significant difference between applying the original technique on standard long-cone periapical radiographs or on orthopantomograms, especially when carrying out measurements on all six selected teeth.     

Application of Kvaal et al.'s age estimation method to panoramic radiographs from Turkish individuals

Age estimation of living adult individuals can be accomplished with limited methods. Radiographic dental methods based on the pulpal narrowing with secondary dentin formation have been presented. In the present study, Kvaal et al.'s method, one of the radiographic dental age estimation methods, was applied to panoramic radiographs from Turkish individuals. The correlation between chronological and estimated ages was examined and the feasibility of length and width measurements of pulp cavity was evaluated for age estimation. The study population consisted of 123 patients with ages ranging from 14 to 57 years. The measurements of the length and width of six types of teeth on digitized panoramic radiographs were performed, and the ratios between tooth and pulp cavity measurements were calculated. Age was estimated using the linear regression models presented by Kvaal et al. and Paewinsky et al. High differences were observed between chronological and estimated ages. Measurement ratios showed no significant or weak correlation with age. The linear regression models were derived using variables that were significantly correlated with age. The determination coefficients of the models varied from 0.035 to 0.345. In conclusion, a difference of more than 12 years in the chronological and estimated ages derived using regression models in literature was found on panoramic radiographs in Turkish individuals. The length and width of the pulp cavity, measured according to the method of Kvaal et al. using panoramic radiographs, were insufficient to precisely estimate the age of Turkish individuals.     

Comparison of dental maturity in children of different ethnic origins: international maturity curves for clinicians

Dental maturity was studied with 9577 dental panoramic tomograms of healthy subjects from 8 countries, aged between 2 and 25 years of age. Demirjian's method based on 7 teeth was used for determining dental maturity scores, establishing gender-specific tables of maturity scores and development graphs. The aim of this study was to give dental maturity standards when the ethnic origin is unknown and to compare the efficiency and applicability of this method to forensic sciences and dental clinicians. The second aim was to compare the dental maturity of these different populations. We noted an high efficiency for International Demirjian's method at 99% CI (0.85% of misclassified and a mean accuracy between 2 to 18 years +/- 2.15 years), which makes it useful for forensic purposes. Nevertheless, this international method is less accurate than Demirjian's method developed for a specific country, because of the inter-ethnic variability obtained by the addition of 8 countries in the dental database. There are inter-ethnic differences classified in three major groups. Australians have the fastest dental maturation and Koreans have the slowest.     

Clinically Detectable Dental Identifiers Observed in Intra‐oral Photographs and Extra‐oral Radiographs,Validated for Human Identification Purposes

Screening the prevalence and pattern of dental identifiers contributes toward the process of human identification. This research investigated the uniqueness of clinical dental identifiers in photographs and radiographs. Panoramic and lateral cephalometric radiographs and five intra‐oral photographs of 1727 subjects were used. In a target set, two observers examined different subjects. In a subset, both observers examined the same subjects (source set). The distance between source and target subjects was quantified for each identifier. The percentage of subjects in the target set being at least as close as the correct subject was assessed. The number of molars (34.6%), missing teeth (42%), and displaced teeth (59.9%) were the most unique identifiers in photographs and panoramic and lateral cephalometric radiographs, respectively. The pattern of rotated teeth (14.9%) was the most unique in photographs, while displaced teeth was in panoramic (37.6%) and lateral cephalometric (54.8%) radiographs. Morphological identifiers were the most unique, highlighting their importance for human identifications.     

Dental age assessment: the applicability of Demirjian method in eastern Turkish children

In the literature, little is known about the applicability of this method in Turkish children. The aim of this study was, therefore, to evaluate the reliability of Demirjian method of age estimation when used for eastern Turkish children. A retrospective study was performed on a sample of panoramic radiographs taken from 807 healthy eastern Turkish children. The stages of dental maturity of the mandibular left seven permanent teeth for each subject using the eight radiographic dental maturity stages demonstrated by Demirjian were evaluated. A paired t-test was used for statistical analysis. The mean difference between the chronological and dental ages ranged from 0.2 to 1.9 years in girls and from 0.4 to 1.3 years in boys. The differences between the chronological and dental ages were statistically significant in all age groups. The applicability of Demirjian method is not suitable for eastern Turkish population.     

Dental CT imaging as a screening tool for dental profiling: advantages and limitations

The use of dental processing software for computed tomography (CT) data (Dentascan) is described on postmortem (pm) CT data for the purpose of pm identification. The software allows reconstructing reformatted images comparable to conventional panoramic dental radiographs by defining a curved reconstruction line along the teeth on oblique images. Three corpses that have been scanned within the virtopsy project were used to test the software for the purpose of dental identification. In every case, dental panoramic images could be reconstructed and compared to antemortem radiographs. The images showed the basic component of teeth (enamel, dentin, and pulp), the anatomic structure of the alveolar bone, missing or unerupted teeth as well as restorations of the teeth that could be used for identification. When streak artifacts due to metal-containing dental work reduced image quality, it was still necessary to perform pm conventional radiographs for comparison of the detailed shape of the restoration. Dental identification or a dental profiling seems to become possible in a noninvasive manner using the Dentascan software.     

The applications of MicroCT in studying age-related tooth morphological change and dental age estimation: A scoping review

Conventional dental age estimation relies on destructive methods such as sectioning and staining, which are unpreferable when the tooth is required for evidential or archeological preservation. MicroCT is a non-destructive, high-resolution imaging technique that allows for accurate morphometrical measurement. Although microCT technology has been applied in a variety of dental studies, studies focusing on dental age-related change and dental age estimation based on microCT imaging remain lacking. Based on the question: “How has microCT technology been applied in studying human age-related tooth morphological change and dental age estimation studies?”, the authors conducted a scoping review in accordance with the Arksey and O'Malley (2005) and the PRISMA-ScR guidelines. A literature search using five major scientific databases identified 452 articles, with 11 full-text articles being eligible to be included in the scoping review. Furthermore, 6 out of the 11 studies performed dental age estimation modeling. An overview of the parameters used in the selected articles revealed a variety of tooth characteristics, such as pulp cavity to whole tooth volume ratio, secondary dentin, as well as the diameter of root canal orifice. The findings of this scoping review highlight the extent microCT is used in studying dental age-related changes, as well as the effectiveness of microCT in dental age estimation studies. This review serves as a guide for future forensic odontology age estimation studies.     

Postmortem dental radiography

Comparison of postmortem and antemortem dental radiographic films or digital images is a common procedure for establishing identity of human remains. This article describes some problems with producing postmortem dental radiographs in a medical examiner setting and gives methods for circumventing these difficulties. Resection of the jaws, when permitted, significantly simplifies the postmortem radiographic technique. When producing an actual postmortem panoramic dental radiograph (orthopantomogram) from a dry skull, stabilization of the specimen for exposure by the moving beam source may be accomplished simply by placing the specimen upside down on an anthropologist's skull ring. Image "burnout" in the anterior segment, which results from absence of the tissues of the neck, may be avoided by appropriate placement of radiodense objects such as "zippered" plastic bags filled with water or other fluid material, freezer gel packs, or a block of self-polymerizing acrylic. These methods may increase future postmortem dental radiography efficiency.     

Accuracy and reliability of cone beam computed tomography of the jaws for comparative forensic identification: a preliminary study

Conventional computed tomography is an emerging modality in forensic identification but is not sufficiently accurate for use in dental identification primarily because of problems with metallic dental restoration-induced streak artifact. In this study, the accuracy and reliability of recording forensic information from cone beam computed tomography (CBCT) scans of the jaws when compared to conventional panoramic radiographs has been analyzed under experimental conditions. Information could be recorded with near-perfect repeatability and reproducibility. Information could also be recorded accurately, the sensitivity being 96.6% (95% CI, 95.1-98.1) and specificity being 98.4% (95% CI, 96.2-100). The metal dental restoration-induced streak artifact was at a level that permitted, in most cases, accurate observations. This is considered an important step in validating CBCT as a tool in comparative dental identification of bodies. It may have a role in mass fatalities and in chemical, biological, radiological, and nuclear incidents, but further studies are required to assess the feasibility of this.     

Dental Age Estimation: A Test of the Reliability of Correctly Identifying a Subject Over 18 Years of Age Using the Gold Standard of Chronological Age as the Comparator

This study was designed to test the reliability of using the third molars to demarcate between child and adult status. A total of 2000 dental panoramic tomographs were used for assessment of the calculated age using the 8‐stage system of tooth development and applied to all four third molars. The LL8 was also assessed using this 8‐stage system. For each tooth development stage, the Normal distribution and percentile summary data were estimated. The calculated dental age compared with the chronological age was statistically significantly different (p < 0.001) for both females and males giving underestimates of the true age. Comparison of single tooth dental age and chronological age was only slightly different. The most important finding is that the assignment to above or below the 18‐year threshold, in the age range 17 years to 19 years, could be wrong on up to 50% of occasions.     

Antemortem records of forensic significance among edentulous individuals

The identification of edentulous individuals is problematic due to poor provision of labelled dental prostheses. Dental records may still provide useful information for odontologists in the comparative identification process. The purpose of this study was to determine the level of forensically significant information contained within the dental records of a population of denture wearers attending the University of Manchester School of Dentistry. Two hundred and two dental records were examined and a proforma completed. The mean age of the patients was 72 years. Medical history were absent in 4% of all records and only 67.8% of the written records were rated as good. Thirty-two percent of the records contained one or more panoramic radiographs but 30% of these were over 3 years old rendering their usefulness in identification procedures questionable. In total only 18% of the examined records contained antemortem information that would enable identification. These data suggest that the process of denture marking is an essential in order to ensure that the identification of this population can be undertaken expediently by dental means.     

Dental maturity in South France: A comparison between Demirjian's method and polynomial functions

The dental maturity of 1031 healthy southern French subjects aged between 2 and 18 years was studied with dental panoramic tomograms. Demirjian's method based on seven and eight teeth has been used to determine maturity scores as a function of age and polynomial functions to determine age as a function of score. We give gender-specific tables of maturity scores and development graphs for each method. The goal of these methods is different because of the nature of the predictions. The percentiles give the dental maturity compared to a standard for a specific age, and polynomial functions give an age prediction with a confidence interval for age. The variations in dental maturity are specific to each population. Thus, the aim of this study is to give the dental maturity standards for southern French children and to compare both the efficiency and applicability of each method in several fields such as forensic sciences or dental health for the clinicians. The addition of the third molar increased the reliability and the capacity of prediction up to 18 years. The polynomial functions showed the best reliability (1.3% of misclassified) and the percentile methods the best accuracy (more or less 1.2 years, on average, between 2 and 18 years of age).     

122例鼻部骨折X线和CT诊断的法医学分析

目的　探讨CT在鼻部骨折诊断中的优点。方法　观察 12 2例鼻损伤伤者的鼻部CT和普通X线片 ,对鼻部诸骨骨折进行对比分析。结果　 12 2例鼻部骨折 (鼻骨骨折 3 2例 ,上颌骨额突骨折 3 3例 ,鼻中隔骨折 9例 ,多发性骨折 48例 )均经CT认定。其中 40例因X线片漏诊直接通过高分辨率鼻骨CT薄层扫描认定 ;82例通过鼻骨侧位X线片显示有鼻部骨折 ,因存在骨折类型认定不准确和 /或有漏诊鼻部其它部位骨折可能 ,通过鼻骨CT认定。结论　鼻骨侧位X线片易漏诊、误诊鼻部骨折 ;鼻骨CT能避免鼻部诸骨骨折的漏诊及误诊 ,且骨折认定准确。     

Dental age in Central Poland

Precise evaluation of the developmental stage of a child is an integral part of both diagnosis and treatment of pediatric patients; it is also essential in forensic medicine and dentistry. Among radiological methods for dental age estimation in children the Demirjian's method is widely used, however original standards elaborated for the French-Canadian population are mostly not suitable for other populations. The aim of the study was to compare the dental age of children from the region of Mazovia (Central Poland) with the developmental standards presented by Demirjian, to analyse sexual dimorphism of dental age in the studied group and to estimate validity of the Demirjian's standards for the studied Polish population. The material consisted of clinical files and panoramic X-ray images of 994 children aged from 6 to 16 in good general health, without development impairments. Chronological ages of the patients were established. Next dental ages were estimated by means of the Demirjian method based on developmental maturity of seven left mandibular permanent teeth. It was found that the standards were significantly different from the chronological ages in the studied population, which means that dental development was considerably accelerated. The most significant acceleration was observed in girls aged 11 and 12, as well as in 13-year-old boys; in both groups a considerable acceleration of the dental age was seen in 6-year-olds. No statistically significant differences between dental ages of girls and boys were observed in particular age groups. There were devised gender-specific equations allowing for adaptation of original Demirjian's scores for estimation of dental age in the population of Mazovia (Central Poland). In conclusion, the developmental standards used by Demirjian are not suitable in the case of the population of children of Central Poland. Therefore, it is necessary to establish new tables for this population.     

Accuracy of different dental age estimation methods on Turkish children

Tooth development is widely used to estimate age or maturation. Dental age estimation is so important for various research works. Numerous methods have been described to estimate dental age based on the dental maturation. The aims of this study were to decide the best method to estimate dental age on Turkish children by reviewing several methods and to illustrate the differences among the methods and to assist future studies. The records of Turkish children between the ages of 7 and 13 years who visited the Department of Pediatric Dentistry of the Faculty of Dentistry of the Süleyman Demirel University in Isparta, Turkey were reviewed and a total of 425 healthy children with complete records, satisfactory panoramic radiographs, similar socio-economic background and ethnic origin were included. Panoramic radiographs were examined with Nolla's, Haavikko's and Demirjian's methods. Dental age was calculated for each method, and the differences between the estimated dental age and the chronological age were compared with paired t-test and Wilcoxon signed rank test. The accuracy of three methods was obtained with ICC (intraclass correlation coefficient). An under-estimation of the dental age was observed by using Nolla's and Haavikko's methods (boys -0.53±0.95, girls -0.57±0.91, both -0.54±0.93; boys -0.60±0.80, girls -0.56±0.81, both -0.58±0.80, respectively) and an over-estimation of the dental age was observed by using Demirjian's method (boys 0.52±0.86, girls 0.75±0.90, both 0.64±0.89). Haavikko's method was more accurate in the dental age estimation compared to the other methods. All of the three methods are not completely suitable for Turkish children and establishment of the population-specific standards is essential and crucial.     

Dental maturity curves in Finnish children: Demirjian's method revisited and polynomial functions for age estimation

Dental maturity was studied from 2213 dental panoramic radiographs of healthy ethnic Finns from southern Finland, aged between 2 and 19 years. The aim was to provide new Finnish maturity tables and curves and to compare the efficiency of Demirjian's method when differently weighted scores and polynomial regressions are used. The inter-ethnic variations lead us to calculate specific Finnish weighted scores. Demirjian's method gives maturity score as a function of age and seems better adapted for clinicians because, in their case, the maturity score is unknown. Polynomial functions give age as a function of maturity score and are statically adapted for age estimation studies. Finnish dental maturity tables and development curves are given for Demirjian's method and for polynomial functions. Sexual dimorphism is established for the same weighted score for girls and boys, and girls present a greater maturity than boys for all of age groups. Polynomial functions are highly reliable (0.19% of misclassifies) and the percentile method, using Finnish weighted scores, is very accurate (+/- 1.95 years on average, between 2 and 18 years of age). This suggests that polynomial functions are most useful in forensic sciences, while Demirjian's method is most useful for dental health clinicians.