Interglobular dentine in first and third molars: relation to hours of sunshine during growth in two archeological populations from England

Vitamin D status in post-medieval Northern England: Insights from dental histology and enamel peptide analysis at Coach Lane, North Shields (AD 1711-1857)

OBJECTIVES

The post-medieval period in Europe saw a dramatic increase in metabolic bone disease related to vitamin D deficiency (VDD). Recent paleopathological work has utilized interglobular dentin (IGD) as a proxy for poor vitamin D status during development, while enamel peptide analysis allows the identification of chromosomal sex in non-adult remains. Here we explore the relationship between sex, the presence of IGD, and macroscopic markers of VDD in an industrial era assemblage from Northeast England.

MATERIALS AND METHODS

25 individuals (9 females, 9 males, 9 unknown sex) from the cemetery site at Coach Lane, North Shields (1711-1857) were selected for paleopathological analysis, histological assessment of IGD, and enamel peptide determination of chromosomal sex.

RESULTS

Ground tooth sections from 21 individuals were of suitable quality for detection of IGD, and enamel peptide analysis confirmed the chromosomal sex of ten individuals. Sixteen individuals (76.1%) exhibited ≥1 episode of IGD. Nine of these (42.8%) exhibited >1 episode and four (19%) exhibited ≥4 episodes in regular intervals. Male sex was significantly associated with the presence of IGD (p = 0.0351; 100% males vs. 54.5% females). Females were more likely to exhibit macroscopic evidence of VDD (45.5% females vs 30% males) but this was not statistically significant.

DISCUSSION AND CONCLUSIONS

Periods of poor mineral metabolism during childhood appear much more prevalent at Coach Lane than macroscopic evidence suggests. Evidence of seasonal IGD episodes indicates that northern latitude played a major role in poor VD status in the Northeast of England. The significant association of IGD with male sex may be due to sex-related differences in dentinal mineralization or a higher risk of poor VD status in males aged <5 years. More work is needed to establish an evidence-based threshold for pathological levels of IGD before the presence of this feature can confidently be used as a biomarker for poor VD status.

The rachitic tooth: Refining the use of interglobular dentine in diagnosing vitamin D deficiency

PURPOSE

This study provides guidelines on how IGD can be differentiated from other microstructures that naturally occur in dentine. Interglobular dentine (IGD) has recently been linked to disruption in vitamin D, calcium, and phosphorous pathways offering a valuable method to investigate vitamin D deficiency in archaeological individuals, but not all dentine defects are IGD.

METHODS

A detailed review of dental literature and dental histology cases gathered from known living and archaeological individuals were incorporated into interpretations.

RESULTS

Investigation of tooth dentine revealed that there can be instances where IGD is not linked to vitamin D deficiency. Information on how to differentiate different forms of defects in dentine were identified.

CONCLUSIONS

We conclude that caution is required when evaluating low-grade IGD, as it may be misidentified.

CONTRIBUTION TO KNOWLEDGE

Information reviewed and assimilated contributes to refining the role of IGD to act as a biological marker, particularly in less severe cases of vitamin D deficiency through provision of clear guidance.

LIMITATIONS OF THIS STUDY

Information from earlier experimental work is limited and until recently understanding of vitamin D and deficiency of this pro-hormone was restricted.

SUGGESTIONS FOR FURTHER RESEARCH

Further data could be gathered from living individuals with known biological/medical information.

Greater sciatic notch morphology: Sex, age, and population differences

The accuracy of a method for visually scoring sex differences in the greater sciatic notch was tested on 296 skeletons of known age and sex. The proportion of correct sex assignments is 80% when all specimens are classified, and 89% when os coxae assigned the score in which the sexes show the greatest overlap are excluded. Although many os coxae (35%) have this sexually intermediate morphology, excluding them has the advantage of substantially reducing sex biases in sexing errors. For both sexes, there is a strong relationship between age at death and sciatic notch score. People who die at a younger age tend to have wider, more feminine-appearing sciatic notches than people of greater longevity. There are also significant population differences. The 18th-19th century English sample from St. Bride's Church has a more feminine morphology than Americans of European or African ancestry. Environmental influences on skeletal development (vitamin D deficiency) appear to provide the most likely explanation for these population differences.