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• Mandibular torus thickness is correlated with age. • The correlation is modified by occlusal status. • Mandibular torus thickness and occlusal status can help identify human corpses. Age estimation is an essential step in identifying human corpses. Several mandibular landmarks have been highlighted as skeletal sites for age estimation since aging causes morphological changes. Reports suggest that mandibular torus size may be associated with aging; however, thorough investigation has not been performed owing to the difficulty in measuring it. Therefore, this study aimed to determine the association between age and mandibular torus thickness using postmortem computed tomography data from Japanese corpses. This study included 2,792 corpses with mean (standard deviation) age of 58.0 (22.4) years (range, 0–101 years) and 67.6 % males. Further, 2,662 (95.3 %), 14 (0.5 %), 59 (2.1 %), and 57 (2.0 %) corpses were in the permanent, mixed, primary, and predental dentition periods, respectively. Multivariable analysis was performed to quantify the impact of age on mandibular torus thickness, adjusting for sex, height, weight, and occlusal contact status. The model also included an interaction term between age and occlusal status because of the potential effect modification by occlusion. Results of the multivariable regression analysis showed that mandibular torus thickness increased with age (the regression coefficients (95 % confidence interval) were 0.6 (0.2–1.0), 0.7 (0.3–1.0), 1.0 (0.6–1.4), 1.3 (0.9–1.7), 1.3 (0.8–1.8), and 1.1 (0.4–1.7) for age groups 30–39, 40–49, 50–59, 60–69, 70–79, and 80–89 years, respectively), especially in males with occlusal contact. A significant association between mandibular torus thickness and age, modified by occlusal status and sex, was identified. Therefore, data regarding the thickness of the mandibular torus and occlusal status may be useful for age estimation in human corpses. [ABSTRACT FROM AUTHOR]

• We applied different surface modifications on-demand to injectable NF-Ms. • Bio-inspired hydrophilic modification by PDA supported the cellular behavior. • Hep-Dopa conjugation improved performance of NF-Ms in loading and delivering rhBMP-2. • SHED engraftment contributes to angiogenesis in ectopic and orthotopic sites. • Conjunctive use of SHED and rhBMP-2 led to vascularized bone tissue regeneration. To provide a suitable 3D microenvironment for bone regeneration, we selected the injectable poly (l-lactic acid) nanofibrous microspheres (PLLA NF-Ms) with different surface modifications to serve as cell micro-carriers or protein vehicles on-demand. Results showed that polydopamine (PDA) modified NF-Ms (PDA-NF-Ms) exhibited good affinity for stem cells from human exfoliated deciduous teeth (SHED), and Heparin-Dopamine (Hep-Dopa) conjugated with NF-Ms (Hep-Dopa NF-Ms) are able to immobilize and slowly release recombinant human bone morphogenic protein-2 (rhBMP-2) efficiently. In vivo evaluations were carried out in both ectopic subcutaneous implantation and orthotopic cranial bone defect nude mouse models (φ = 4 mm). The results suggested that PDA-NF-Ms could support SHED survival over 4 weeks. All experimental groups with SHED/PDA-NF-Ms engraftment showed angiogenesis activity. But, no effect of SHED/PDA-NF-Ms on osteogenesis was found in ectopic implantation, which is different from the result in cranial defect. The rhBMP-2 released from Hep-Dopa NF-Ms could significantly guide bone tissue regeneration in both ectopic and orthotopic site. At 8 weeks, both BMP-2 group and dual group showed large amounts of bone formation in situ, despite the fact that quantitative results of micro-CT did not demonstrate significant difference between them. More blood vessels were observed in SHED and Dual groups, which verifies the quality improvement of regenerated osseous tissues. Regeneration of vascularized bone tissue was, thus, highly expected upon implanting SHED/PDA-NF-Ms and rhBMP-2-loaded Hep-Dopa NF-Ms together. The strategy developed in this study represents a promising method for satisfactorily promoting bone regeneration. [ABSTRACT FROM AUTHOR]

Diacodexeidae are the first representatives of Artiodactyla in the fossil record. Their first occurrence is at the very base of the Ypresian (earliest Eocene, 56.0 Ma) with Diacodexis , a genus well diversified during the early Eocene in Europe, especially during the MP7–MP8 + 9 interval. However, most of European species are documented by scarce material, retrieved from single localities. In this work, we describe new Diacodexis material from ∼MP7 and ∼MP8 + 9 localities of Southern Europe, including material of D. antunesi from Silveirinha, considered as the most primitive European Diacodexis species, and material from three localities from Southern France (Fordones, Palette, and La Borie). The new material documents Diacodexis premolar morphology and deciduous dentition which bear potentially important phylogenetic information, as well as astragali, including a specimen from Silveirinha that constitutes the earliest occurrence of an astragalus of the genus Diacodexis in the European fossil record. Investigation of the enamel microstructure reveals that early European species had a simple enamel pattern with one-layered Schmelzmuster composed of ‘basic’ radial enamel only, instead of the two-layered Schmelzmuster (thin radial enamel + thick layer of Hunter-Schreger bands) observed on North American species and so far considered to represent the primitive condition within Artiodactyla. In accordance with previous studies, our observations highlight that Diacodexis gigasei from Belgium is morphologically closer to the North American species D. ilicis than to D. antunesi from Portugal. The latter species, together with D . aff. antunesi from Fordones, appears to be morphologically closer to the Asiatic taxa D. indicus and D. pakistanensis . Finally, we found numerous similarities between D. cf. gigasei from Palette and D. gigasei , a result that challenges the intra-European provincialism that characterizes the earliest Ypresian. Diacodexis gigasei could be one of the rare species shared by the northwestern and southwestern European bioprovinces. [ABSTRACT FROM AUTHOR]

Objectives The aim of this study was to associate weight and height with the timing of deciduous tooth emergence. Methods 1756 children, aged from 1 to 33 months (755 females and 1001 males) had been previously examined for the timing of deciduous tooth emergence and their weights and heights measured. Children were categorized into weight and height groups (underweight, normal, overweight, short stature, normal and tall stature). Probit regression analysis was used to calculate the ages at emergence of each deciduous tooth. Tooth emergence ages were compared pairwise across the weight and height groups. Results The deciduous dentition emerged between 7.9–31.5, 7.8–29.6 and 6.3–26.5 months in the underweight, normal and overweight children, respectively. In the height groups, the ranges were 9.0–31.3, 7.4–27.0 and 6.7–24.3 in the short, normal and tall children, respectively. The extremes of weight and height were related to the times at deciduous tooth emergence where a substantial increase in weight or height was associated with earlier emergence, and vice versa. However, only canines, lateral incisors and upper central incisor showed statistically significant association with weight and none of the teeth exhibited statistically significant association with height. Moreover, no emergence sequence change was associated with weight and height. Conclusions The present study provides the first weight and height– specific data on the timing of deciduous tooth emergence. Although both weight and height are generally associated with the timing of deciduous tooth emergence, weight shows a stronger association for canines, lateral incisors and upper central incisor. The findings will aid assessing normal emergence timing in children with variant weights and heights. [ABSTRACT FROM AUTHOR]

• Little dental radiographic data are available for tooth development in newborns. • We studied the radiological and autopsy findings of five term babies. • Deciduous teeth were calcified at birth (day 0 of life) • The first permanent molar was calcified at 1 month. • The mandibular symphysis was incompletely ossified in the first month. Although dental radiography is a valuable tool for age estimation in forensic anthropology and odontology, very limited radiological data are available regarding tooth development in healthy newborn babies during the first month of life. This study aimed to describe the radiological findings of tooth development in babies aged 0 days to 1 month. We analyzed the postmortem findings of five newborn babies with no known natural cause of death who had undergone autopsy, computed tomography (CT), and dental radiography. We estimated the gestational age for the babies aged 0 days and analyzed the condition of mandibular symphysis, existence of tooth germs, and presence or absence of calcification of the first permanent molars of all the babies. The calcified form of 20 deciduous teeth, tooth germs of the permanent upper and lower first molars, and non-calcified mandibular symphysis were observed in each case. However, calcification of the first permanent molar was observed in only two 1-month-old babies. The dental radiographic findings and anthropometric measurements of non-skeletonized, non-mummified term babies confirmed calcification of all the deciduous teeth and the first permanent molar at the age of 0 days and 1 month, respectively. [ABSTRACT FROM AUTHOR]

Despite new discoveries of human fossil remains, some aspects of paleoanthropological research are biased by the poor sample size, which limits our understanding of intra-species variability among the different hominin species. In this context, continuous assessment and reassessment of human fossil remains discovered decades ago, and often unknown to the scientific community, represent an opportunity to address this issue. Moreover, deciduous teeth are less studied than permanent dentitions, an aspect which contributes to limit our understanding. In the present study, we provide a detailed description of Tagliente 3 (upper right second deciduous molar) and Tagliente 4 (lower left deciduous canine), two deciduous teeth from Riparo Tagliente (Stallavena di Grezzana, Verona) attributed to Homo neanderthalensis . In terms of morphology and size, Tagliente 3 presents typical Neandertal derived features (e.g., likely large hypocone and complex topography of the enamel-dentine junction). Although deciduous canines usually do not provide substantial morphologically diagnostic information, Tagliente 4 falls in the upper range of the Neandertal variability for its bucco-lingual diameter. In terms of tissue proportions both teeth fall within the Neandertal range of variation: Tagliente 3 for the enamel thickness distribution and Tagliente 4 for the volume of the crown dentine. This work contributes to increase our knowledge on the variability of Neandertal deciduous dentition. [ABSTRACT FROM AUTHOR]

The skull and some mandibular fragments with deciduous dentition of a chalicothere are studied in the present article. The studied material is described and compared with the known material from other localities of Greece and neighboring areas. The comparisons indicate that the studied material shares morphological and metrical similarities with the well-known ancylothere of Greece, Ancylotherium pentelicum (Gaudry and Lartet, 1856). The geographic and stratigraphic distribution of the genus and species are also discussed. Ancylotherium shows a wide expansion covering much of the Old World. The species Ancylotherium pentelicum is well distributed in the Greco-Iranian Province but its main occurrence involves the Balkans and Asia Minor; although it was recognized in Central Asia, its occurrence appears unusual based on current knowledge, but ongoing research in this area will possibly unveil more A. pentelicum -bearing sites in the future. Despite its great expansion, the known material of A. pentelicum is scarce in comparison to the other large members of the associated fauna. In Eurasia, A. pentelicum is known mainly from the Turolian, while recently Ancylotherium was recognized in the Vallesian of the Eastern Mediterranean region as a new species: A. hellenicum . In addition there are some limited evidences for its presence in the Vallesian of Spain. [ABSTRACT FROM AUTHOR]

In this article, we present the proboscidean assemblage from the upper Miocene vertebrate locality Nikiti 2 (Chalkidiki Peninsula, Macedonia, Greece). Based on the dental remains, the material belongs exclusively to the genus Choerolophodon . The morphology of the dp3/DP3 and the dimensions of the deciduous dentition clearly distinguish the Nikiti 2 choerolophodont from the early Vallesian Choerolophodon anatolicus and permit its assignment to C. pentelici . C. pentelici is represented in SE Europe–SW Asia by a primitive morph, known from the late Vallesian–earliest Turolian, and an advanced morph Turolian in age. The morphometric features of the Nikiti 2 specimens and their comparison with the choerolophodont material from upper Miocene localities of the wider region indicate that the Nikiti 2 C. pentelici belongs to the advanced morph of the species, suggestive for a Turolian age for the locality. These results agree with the rest of the fauna, which is correlated to the early Turolian (MN 11). [ABSTRACT FROM AUTHOR]

Objectives The aim of the study was to map the dental health status in non-adult individuals and to verify whether and how the existence of caries in the non-adult age group is associated with the different socio-economic status of early medieval populations. Material and methods We studied the dental remains from the acropolis of the Mikulčice settlement agglomeration, where members of the higher social classes were buried, and from the Mikulčice hinterland. Overall, we evaluated 2544 teeth/3714 alveoli of deciduous dentition and 1938 teeth/2128 alveoli of permanent dentition. We determined the number of individuals with dental caries (i.e., caries frequency index, F-CE) and the proportion of teeth/alveoli with caries/ante-mortem tooth loss (i.e., caries intensity index, I-CE). Results We found no statistical significant difference in the F-CE values between the Mikulčice hinterland and the acropolis. In addition, we found no statistically significant difference in the proportion of teeth with carious lesions (I-CE) either in the case of deciduous dentition or in the case of permanent dentition between the hinterland and the acropolis. In the case of permanent dentition, the statistically significant highest proportion of carious lesions (I-CE) was found in Mikulčice I ( p ≤ 0.05). We confirmed an increase in the rate of caries with age. Conclusions The level of caries at all of the studied medieval locations was very low. We presume that lifestyle and the associated dietary habits and hygienic practices of the individuals or population groups had a greater influence on dental caries than did the socio-economic status of these individuals. [ABSTRACT FROM AUTHOR]

Objective The aim of this study was to provide the timing and sequence of deciduous tooth emergence in a sample of Jordanian children. Design A total of 1988 (885 female and 1103 male) children aged from 1 to 45 months recruited from nursery schools and child and maternity health centres in the northern, middle and southern regions of Jordan underwent a dental examination for the detection of deciduous tooth emergence. Children were categorized into 15 3-month-apart age groups. Using Probit regression (SPSS version 16), the median age of emergence per tooth was calculated for the total sample and for both genders. Results The period for acquiring deciduous dentition in the total sample ranged from 8.2 to 27.5 months. In either of the maxillary and mandibular arches, deciduous dentition emerged in the following order: central incisor, lateral incisor, first molar, canine and second molar. In addition, there were insignificant differences across side and there was a significant mandibular precedence of the central incisor although the maxillary precedence in the rest of the teeth was insignificant. Moreover, teeth emerged earlier in females although none of the inter-gender differences were significant. Conclusions The first standards of the timing and sequence of deciduous tooth emergence specific to the Jordanian population were provided. These standards will be used along with the previously published standards of permanent tooth emergence to aid managing patients in paediatric dentistry and orthodontics and will find applications in forensic and police sciences and in anthropological research. [ABSTRACT FROM AUTHOR]

Sinomastodon (Proboscidea, Mammalia) is a unique brevirostrine trilophodont gomphotheriid from Eurasia, which mainly occurs in China during the Plio-Pleistocene. Although much is known about adult individuals, the morphology of juveniles of this taxon is still poorly understood due to the scarcity of pertinent fossils. The present contribution represents the first detailed systematic study of the mandible and deciduous dentition of juvenile individuals of Sinomastodon jiangnanensis from the early Early Pleistocene (2.14–2.15 Ma) Renzidong Cave of eastern China. Based on morphological comparisons, the Renzidong juvenile mandible bears, on one hand, the transitional characteristics between the typical long-jawed trilophodont and elephantoid proboscideans, and, on the other hand, more primitive features than adult mandibles of Sinomastodon . This study of juvenile individuals of S. jiangnanensis provides new information to enhance the diagnosis of S. jiangnanensis , and confirms the validity of the species. It also provides evidence to show that the morphological transition of genus Sinomastodon from Neogene to Quaternary is mirrored in adult and juvenile individuals. [ABSTRACT FROM AUTHOR]

The objective of this study of the maturation of deciduous dentition was to offer a novel age-estimation method for Mediterranean populations, using the osteological collection of fetuses, infants, and young children in the Anthropology Laboratory of Granada University (Spain) as study material. After excluding premature newborns and infants with disease, the final study sample comprised 1303 deciduous teeth suitable for analysis from 138 individuals (80 male, 58 female) aged between 24 weeks in utero and 6 years. Eleven mineralization stages were defined for the dental maturation analysis, and the alveolar emergence was also studied. The criteria published by Demirjian et al. (Hum. Biol. 45 (1973) 211), Moorrees et al. (J. Dent. Res. 42 (1963a) 490), and Liversidge et al. (Am. J. Phys. Anthropol. 123 (2004) 172) were combined and modified for this purpose. The reproducibility of the proposed method is supported by the low intra- and inter-observer error in the identification of these development stages. The results provide information on the mean age of attainment of each of 11 mineralization stages and on the average age for each stage in each deciduous tooth type, considering each sex separately and both sexes combined. [ABSTRACT FROM AUTHOR]

• Deciduous tooth calcification could be detected in over 19-week-old fetuses. • Bone calcification bones started earlier than deciduous teeth calcification. • Bone calcification rate was slower compared to that of the deciduous teeth. Fetal age is estimated widely by body length and weight and skeletal or dental development and maturation. Regarding dental development, dental development charts reported by Schour and Massler and Ubelaker are well known. We tried to calculate the calcification rate of the deciduous teeth, mandibular cortical bone, and clavicle in fetuses utilizing postmortem computed tomography (CT) image analysis. The CT values within the circumferential area of the region of interest were automatically calculated using a software, and the calcification rate was calculated by performing single regression analysis. Our results showed that deciduous tooth calcification could be detected in over 19-week-old fetuses using CT images. The calcification of bones (mandibular cortical bone and clavicle) started earlier than the calcification of deciduous teeth. However, the calcification rate of the bones was slower compared to that of the deciduous teeth. The calcification rate of the deciduous teeth in fetuses using CT value may be effective to estimate fetal age and evaluate deciduous teeth development, suggesting that our established method is effective for age estimation in forensic dentistry. [ABSTRACT FROM AUTHOR]

Abstract: Reconstructing segmental mandibular defects in children of deciduous dentition is a challenge. The authors treated a 23-month-old girl with a segmental mandibular defect secondary to tumour resection. Considering the unpredictable negative impacts of the autogenous bone grafting method on the musculoskeletal system of the donor sites, which was growing rapidly at this age, the authors applied transport disc distraction osteogenesis (TDDO) to reconstruct the mandible discontinuity. To the best of the authors’ knowledge, this is the first time TDDO has been used for mandible reconstruction in such a young patient with deciduous dentition. Aesthetics and function were restored satisfactorily at the end of treatment. The facial appearance and occlusion were stable through the 35 month follow-up, possibly due to the growth of the regenerated bone parallel with the rest of the maxillofacial skeleton. The satisfactory reconstruction also contributed to the patient''s physical and psychological development. The success of mandible reconstruction with TDDO in this study casts new light on the management of segmental mandibular defect in children with deciduous dentition. [Copyright &y& Elsevier]

One of the most important yet unresolved tasks facing therapeutic dentistry is the problem of efficient personalised diagnostics of pathological processes in the dentine tissues of human teeth. In this regard, dentine fluid is an ideal screening candidate, which acts as an important factor in the development of dentine caries. However, the serious difficulty and practical impossibility of dentine fluid sampling in vivo is the main obstacle to its use in advancing a new line of diagnostics. Extracting gingival crevicular fluid for diagnosing is a much simpler approach. Therefore, we sought to establish the molecular composition and protein conformation of blood, dentine fluid, and gingival fluid during the development of dentine caries using synchrotron FTIR investigations. Ten participants aged 22–28 participated in the study. Each participant had teeth with lesion foci related to primary and secondary enamel surface caries (tooth decay). Three biological fluid samples were obtained for each participant: dentine fluid, gingival crevicular fluid, and blood. The molecular composition of the samples was investigated using FTIR synchrotron spectroscopy technique. Based on the mathematical simulation of absorption band Amide I in the FTIR spectra of the samples, it was found that the development of pathological processes of the carious type in dentine tissue affects the molecular composition of the biological fluids coming in contact with hard dental tissue. In addition, for the first time, we observed an increased content of thiocyanates and complex esters as well as the presence of anti-inflammatory cytokines, and their interaction with the secondary protein structure in the dentine fluid and gingival crevicular fluid for people with pathological carious processes in the dental tissues. The detected features in the FTIR spectra of biological fluids within the oral cavity in combination with the well-known in literature spectral markers of the development of carious process in dentine prove to be significant, reliable signatures of pathology that can relatively easily detected in the analysis of gingival fluid. [ABSTRACT FROM AUTHOR]

Stem cells from human exfoliated deciduous teeth (SHED) are considered the best current source of human stem cells due to their ability to differentiate into multiple cell lineages. Dynamic co-culture systems can improve the culture environment, as they provide cells with signaling factors, extracellular matrixes, and cellular shear force, as well as enable the formation of heterotypic clusters. We seeded SHED in 3D silk fibroin porous scaffolds under static and dynamic cultures for 28 days, using the NIH3T3 cultivated medium as an induction agent. Many hepatospheres formed in these porous scaffolds, and cellular viability was shown to continually increase by MTT assays. Hepatic AFP and ALB gene expression, as well as glycogen storage, albumin secretion, and urea synthesis, were greater in cells in the 3D porous scaffold under a dynamic culture than in those cultured under 3D static culture and petri dish conditions. However, the 3D static culture is still superior to the traditional petri dish culture. The NIH3T3 cultivated medium can significantly induce hepatic differentiation of SHED, while the 3D dynamic culture system significantly enhances hepatic differentiation of SHED. This study provides alternative sources of hepatocytes for liver disease treatment. • Dynamic co-culture systems can improve the culture environment. • NIH3T3 cultivated medium can significantly induce hepatic differentiation of SHED. • Differentiated cells from SHED exhibit special characteristics of hepatocytes. [ABSTRACT FROM AUTHOR]

In the present article, we study the proboscidean remains from three upper Miocene localities of Northern Greece: Thermopigi (Serres), Neokaisareia (Pieria) and Platania (Drama). The material from the Turolian locality of Thermopigi includes only postcranial specimens. The morphological features of the scapula indicate the presence of the deinotheriid Deinotherium sp., whereas the rest of the specimens are morphologically distinct from Deinotherium and can be referred to Elephantimorpha indet. The material from Neokaisareia consists of a partial skeleton of a single individual and is attributed to the mammutid Mammut sp. (M. obliquelophus ?). This taxon is known in Greece from the early–middle Turolian. The Platania proboscidean belongs to the tetralophodont amebelodontid Konobelodon cf. atticus. The genus Konobelodon was already present during the Vallesian of the wider area, but the lower tusk of the Platania shovel-tusker presents some morphological and metrical differences from the Vallesian representative, yet it has also smaller dimensions in its deciduous dentition than the morphologically similar Turolian specimens. The type locality of K. atticus is Pikermi (Attica, Greece), correlated to the middle Turolian, but the known biostratigraphic range of this species covers the entire Turolian. Platania is possibly correlated close to the Vallesian/Turolian boundary and the possible record of this species could document one of its earliest occurrences. [ABSTRACT FROM AUTHOR]

• Many in vitro studies apply polished (human or bovine) enamel. • Highest erosive substance loss was found for natural enamel without pellicle. • Lowest erosive substance loss was found for polished enamel with pellicle. • Natural bovine enamel, therefore, seems less erosion-resistant than polished enamel. • This fact needs to be considered in the design of future erosion studies. Aim of this in vitro study was to investigate erosive tooth loss in dependence of the enamel surface structure and presence of an acquired pellicle. Enamel specimens from 19 bovine incisors (4 specimens/incisor) were allocated to four experimental groups (n = 19). The surfaces of half of the specimens were polished (two groups), while the other half was left native (two groups). Specimens of one polished and one native group were placed in pooled human saliva (30 min) for the formation of an acquired pellicle. Thereafter, all specimens were demineralized by superfusion with hydrochloric acid (17 min, pH 2.3) with collection of the superfluent. Erosive substance loss was determined by measuring the dissolved calcium content using a colorimetric assay with Arsenazo III reagent. Differences in erosive substance loss were statistically analyzed with respect to enamel surface and pellicle. A linear mixed effects model was fitted to the data and pairwise differences between groups were evaluated (significance level α= 0.05). Enamel surface structure (p < 0.001) and presence of pellicle (p = 0.01) had a significant effect on erosive substance loss. Polished surfaces with pellicle showed the lowest cumulative calcium release [nmol Ca/mm2] (means ± standard deviation: 48+/−5), followed by polished specimens without (51+/−9) and native specimens with pellicle (54+/−10). No significant differences were found between these groups. Highest cumulative calcium release was found for native specimens without pellicle (61+/−9; p < 0.05). Both enamel surface structure and the acquired pellicle are important determinants of the susceptibility to erosive tooth loss. [ABSTRACT FROM AUTHOR]

• The rs13115627-GG genotype may be protective against MIH in our population. • The rs1784418-TT genotype and rs1800972-CC genotype related to an increased MIH risk. • The carriers with rs1996315‐AG and rs923911-AC genotypes have a higher MIH risk. The aim of this study was to evaluate whether individual genetic factors involved in amelogenesis, the immune response and water channel proteins may increase the susceptibility to Molar-Incisor Hypomineralization (MIH) in Chinese children. DNA samples were collected from 86 cases with MIH cases and 344 controls. Sixteen single-nucleotide polymorphisms (SNPs) were investigated. Logistic regression analysis was performed to assess association between SNPs and the risk of MIH. Our results showed that the risk of MIH in the rs13115627-AA genotype carriers and the rs1784418-TT genotype carriers were significantly higher than that among those with the rs13115627-GG genotype (OR (95 % CI)) = 4.942 (0.658-37.131) and the rs1784418-CT genotype (OR (95 % CI)) = 2.023 (1.63–3.521). The population with the rs1800972‐CC genotype and the rs1800972‐C allele had a higher risk to develop MIH, OR (95 % CI) = 2.284 (1.267–4.115), OR (95 % CI) = 2.427 (1.493–3.953) respectively. In the Aquaporin 5(AQP5) gene, we individually analyzed two SNPs, rs1996315 and rs923911. We found no significant associations between them and MIH. However, in the analysis of the gene-gene interactions, we discovered a significant two‐locus model (P = 0.023) involving rs1996315 and rs923911. Participants with the rs1996315‐AG and rs923911-AC genotypes had the highest MIH risk, compared to participants with the rs1996315‐GG and rs923911-CC genotypes, OR (95 % CI) = 3.603 (1.147–11.318). This study showed that genetic variants in the AMBN, MMP20 and DEFB1 genes may contribute to MIH in the permanent dentition of children. Moreover, interactions among AQP5 gene may also increase the MIH susceptibility. [ABSTRACT FROM AUTHOR]

Background: Physiological disruptions to early human development have implications for health and disease in later life. Limited research has explored how prenatal factors influence dental development in children of mothers with known pregnancy conditions. Enamel in human deciduous teeth begins forming in utero and is highly susceptible to physiological upsets experienced perinatally. The moment of birth itself is marked in deciduous enamel by the Neonatal Line (NNL) as a baby transitions from the uterine to external environment. This study evaluates the effect of maternal health factors that include stress and alcohol consumption on NNL in teeth from Australian children.Study Design and Subjects: Mothers (n = 53) were interviewed about their health during pregnancy and experience of birth. Sixty-five deciduous teeth (incisors, molars, one canine) from their children were donated for histological examination. Neonatal line thickness was measured from thin sections and evaluated against maternal and neonatal factors using statistical analyses, controlling for tooth type and birth number.Results and Conclusions: The only maternal factor of a statistically significant effect on NNL thickness was alcohol consumption. Children of mothers who drank occasionally during pregnancy had a thicker NNL when compared to children of mothers who abstained. These results suggest that maternal lifestyle factors influence NNL formation possibly due to physiological changes that disrupt calcium homeostasis during enamel deposition. We highlight large intra-specific variation in human NNL expression. The potential of dental sampling in identifying children with prenatal exposure to alcohol is suggested. [ABSTRACT FROM AUTHOR]

Out of all the available methods for estimating age at death from immature human skeletal remains, those based on odontometric variables of deciduous dentition have proved to be one of the most accurate. The development of odontometric methods has been improved through the creation of documented human osteological collections, allowing their validation in different populations. The present study aims to test the regression equations for age estimation proposed by Liversidge et al. 1993, Irurita Olivares et al. 2014, and Cardoso et al. 2019, on the basis of the maximum length of deciduous teeth in an Argentinian sample of 35 infants of known age at death. The results showed that the absolute mean difference between estimated and chronological age was 5.76±6.33 weeks for Liversidge's method, 5.71±6.41 weeks for Irurita Olivares's method, and 6.79±5.80 for Cardoso's method. It was also found that, for Liversidge's method, the canines provided the most accurate and the least biased estimations. For Irurita Olivares's method, mandibular anterior teeth were the most accurate, while the first mandibular molars offered the least biased estimations. For Cardoso's method, the canines presented the most accurate estimations, while the lateral incisors the least biased ones. Finally, 95% confidence intervals of estimated ages were calculated for each method, finding that Irurita Olivares's method provided the most reliable age estimations when using mandibular central incisors and mandibular first molars. [ABSTRACT FROM AUTHOR]