Sex- and Age-related Differences in Primary and Secondary Dentin Formation

Abstract

Clinical studies carried out on dentin thickness in adults, as well as experimental studies carried out on ovariectomized animals, indicate that odontoblast activity, like that of osteoblastic cells, differs in the two sexes. To examine the evidence for differences in odontoblast activity before puberty, we have measured dentin thickness and other crown dimensions from bite-wing radiographs of the lower first molars in 240 children aged 4-16 years. The radiographs were obtained from pedodontic clinics throughout Israel. Only teeth without caries or fillings were used, and the study population had minimal attrition. The results showed that dentin thickness, measured on the roof of the pulp chamber, was significantly greater in boys than in girls at all ages, and that the differences increased during puberty. The differences remained highly significant even when standardized for crown size. They demonstrate that dimorphism in dentin thickness is present even in the earliest stages of odontogenesis and increase with puberty.

Keywords

Dentin teeth dimorphism odontogenesis odontoblasts.

Get full access to this article

View all access options for this article.

References

Alvesalo L. (1997). Sex chromosome and human growth. A dental approach . Hum Genet 101:1-5.

Drusini AG , Toso O. , Ranzato C. (1997). The coronal pulp cavity index: a biomarker for age determination in human adults. Am J Phys Anthropol 103:353-363.

Franquin JC , Remusat M. , Abou Hashiech I. , Dejou J. (1998). Immunocytochemical detection of apoptosis in human odontoblasts. Eur J Oral Sci 106 (Suppl 1):384-387.

Gustafson G. (1950). Age determinations on teeth. J Am Dent Soc 41:45-54.

Harris EF , Hicks JD (1998). A radiographic assessment of enamel thickness in human maxillary incisors. Arch Oral Biol 43:825-831.

Hietala EL , Larmas M. (1992). The effect of ovariectomy on dentin formation and caries in adult rats. Acta Odontol Scand 50:337-343.

Hietala EL , Larmas M. , Salo T. ( 1998). Localization of estrogen-receptor-related antigen in human odontoblasts. J Dent Res 67:1384-1387.

Mjor IA ( 1986). Age changes in the teeth. In: Geriatric dentistry: a textbook of oral gerontology. Holm-Pedersen P , Loe H , editors. St. Louis: C.V. Mosby Co., pp. 94-101.

Moorrees CFA , Fanning EA , Hunt EE Jr (1963). Age variation of formation stages for ten permanent teeth. J Dent Res 42:1490-1502.

10.

Philippas GG (1961). Influence of occlusal wear and age on formation of dentin and size of pulp chamber. J Dent Res 40:1186-1198.

11.

Philippas GG , Applebaum E. (1966). Age factor in secondary dentin formation. J Dent Res 45:778-789.

12.

Solheim T. (1992). Amount of secondary dentin as an indicator of age. Scand J Dent Res 100:193-199.

13.

Stroud JL , Buschang PH , Goaz PW ( 1994). Sexual dimorphism in mesiodistal dentin and enamel thickness . Dentomaxillofac Radiol 23:169-171.

14.

Svanberg M. , Hietala EL , Knuuttila M. (1994). The effect of dietary xylitol on dentin formation in ovariectomized rats. Acta Odontol Scand 52:82-85.

15.

Ten Cate AR (1998). Oral histology: developmental structure and function . 5th rev. ed. St. Louis: The C.V. Mosby Co.

16.

Woods MA , Robinson QC , Harris EF (1990). Age progressive changes in pulp widths and root lengths during adulthood: a study of American blacks and whites. Gerodontology 9:41-50.

17.

Zilberman U. , Smith P. (1994). Sex discrimination using tooth components measured from bite-wing radiographs (abstract). Am J Phys Anthropol (Suppl 18):214.

18.

Zilberman U. , Skinner M. , Smith P. (1992). Tooth components of mandibular deciduous molars of Homo sapiens sapiens and Homo sapiens neanderthalensis. Am J Phys Anthropol 87:255-262.

19.

Zilberman U. , Smith P. , Alvesalo L. (2000). Crown components of mandibular molar teeth in 45,X females (Turner Syndrome). Arch Oral Biol 45:217-225.