Anatomy and development of the teeth
- J Tim Wright, DDS, MS
J Tim Wright, DDS, MS
- Professor of Pediatric Dentistry
- The University of North Carolina
The close relationship among oral, systemic, and psychologic health requires that oral health be evaluated thoroughly as part of health maintenance supervision. An understanding of the normal sequence and patterns of tooth eruption is the foundation for identifying and treating children with abnormal dental development and optimizing their oral health.
The normal anatomy and development of human dentition are reviewed here. Problems in dental development and syndromes associated with abnormal dental development are discussed separately. (See "Developmental defects of the teeth".)
Dental development proceeds from approximately the sixth week in utero through late adolescence. It involves the formation, eruption, and shedding of the 20 primary (deciduous or shedding) teeth, as well as the formation and eruption of the 32 permanent teeth. Throughout this prolonged span of development, the teeth are subject to both genetic and environmental influence. The timing, location, morphology, structure, and composition of teeth primarily are genetically controlled and are regulated by thousands of genes [1,2].
In addition to their role in speech and facial aesthetics, the teeth provide an efficient system of mastication with incising, tearing, and grinding capabilities. The unique composition and structure of teeth allow them to survive the forces and wear of mastication; alteration of the composition or structure of the teeth affects their durability, resistance to fracture, and retention in the oral cavity.
Each tooth has a visible crown that projects above the gingiva (gum), with one or more roots extending into the alveolar bone of the maxilla or mandible (figure 1). The crown and root meet at the neck of the tooth. The tooth forms a peg and socket joint with the alveolar bone and is held in place by the periodontal membrane that allows slight movement of the tooth.
- Maas R, Bei M. The genetic control of early tooth development. Crit Rev Oral Biol Med 1997; 8:4.
- Hu S, Parker J, Wright JT. Towards unraveling the human tooth transcriptome: the dentome. PLoS One 2015; 10:e0124801.
- Simmer JP, Fincham AG. Molecular mechanisms of dental enamel formation. Crit Rev Oral Biol Med 1995; 6:84.
- Robinson C, Weatherell JA, Hallsworth AS. Variatoon in composition of dental enamel within thin ground tooth sections. Caries Res 1971; 5:44.
- Robinson C, Fuchs P, Deutsch D, Weatherell JA. Four chemically distinct stages in developing enamel from bovine incisor teeth. Caries Res 1978; 12:1.
- Weatherell JA, Deutsch D, Robinson C, Hallsworth AS. Fluoride concentrations in developing enamel. Nature 1975; 256:230.
- Tziafas D. Basic mechanisms of cytodifferentiation and dentinogenesis during dental pulp repair. Int J Dev Biol 1995; 39:281.
- Linde A, Goldberg M. Dentinogenesis. Crit Rev Oral Biol Med 1993; 4:679.
- Butler WT, Ritchie HH, Bronckers AL. Extracellular matrix proteins of dentine. In: Dental enamel, John Wiley & Sons, Chichester, UK 1997. p.107.
- Pashley DH. Dynamics of the pulpo-dentin complex. Crit Rev Oral Biol Med 1996; 7:104.
- Solheim T. Amount of secondary dentin as an indicator of age. Scand J Dent Res 1992; 100:193.
- Jung IY, Lee SJ, Hargreaves KM. Biologically based treatment of immature permanent teeth with pulpal necrosis: a case series. J Endod 2008; 34:876.
- Yamamoto T, Hinrichsen KV. The development of cellular cementum in rat molars, with special reference to the fiber arrangement. Anat Embryol (Berl) 1993; 188:537.
- Ripamonti U, Reddi AH. Tissue engineering, morphogenesis, and regeneration of the periodontal tissues by bone morphogenetic proteins. Crit Rev Oral Biol Med 1997; 8:154.
- Thesleff I, Aberg T. Tooth morphogenesis and differentiation of ameloblasts. In: Dental enamel, John Wiley & Sons, Chichester, UK 1997. p.3.
- Thesleff I. Homeobox genes and growth factors in regulation of craniofacial and tooth morphogenesis. Acta Odontol Scand 1995; 53:129.
- Thesleff I, Nieminen P. Tooth morphogenesis and cell differentiation. Curr Opin Cell Biol 1996; 8:844.
- Sharpe PT. Homeobox genes and orofacial development. Connect Tissue Res 1995; 32:17.
- Marks SC Jr. The basic and applied biology of tooth eruption. Connect Tissue Res 1995; 32:149.
- Wise GE. Cell and molecular biology of tooth eruption. In: The biological mechanisms of tooth eruption, resorption and replacement by dental implant, Davidovitch Z (Ed), EBSCO Media, Birmingham, AL 1998.
- Lunt RC, Law DB. A review of the chronology of eruption of deciduous teeth. J Am Dent Assoc 1974; 89:872.
- Demirjian A, Levesque GY. Sexual differences in dental development and prediction of emergence. J Dent Res 1980; 59:1110.
- Dixon GH, Stewart RE. Genetic aspects of anomalous tooth development. In: Oral Facial Genetics, Stewart RE, Prescott GE (Eds), CV Mosby Company, St. Louis 1976. p.124.
- Wake M, Hesketh K, Allen M. Parent beliefs about infant teething: a survey of Australian parents. J Paediatr Child Health 1999; 35:446.
- King DL. Teething revisited. Pediatr Dent 1994; 16:179.
- Wake M, Hesketh K, Lucas J. Teething and tooth eruption in infants: A cohort study. Pediatrics 2000; 106:1374.
- Wake M, Hesketh K. Teething symptoms: cross sectional survey of five groups of child health professionals. BMJ 2002; 325:814.
- Macknin ML, Piedmonte M, Jacobs J, Skibinski C. Symptoms associated with infant teething: a prospective study. Pediatrics 2000; 105:747.
- Massignan C, Cardoso M, Porporatti AL, et al. Signs and Symptoms of Primary Tooth Eruption: A Meta-analysis. Pediatrics 2016; 137:e20153501.
- Ramos-Jorge J, Pordeus IA, Ramos-Jorge ML, Paiva SM. Prospective longitudinal study of signs and symptoms associated with primary tooth eruption. Pediatrics 2011; 128:471.
- Swann IL. Teething complications, a persisting misconception. Postgrad Med J 1979; 55:24.
- Jaber L, Cohen IJ, Mor A. Fever associated with teething. Arch Dis Child 1992; 67:233.
- Tighe M, Roe MF. Does a teething child need serious illness excluding? Arch Dis Child 2007; 92:266.
- Saint Louis C. 10 Infant Deaths May Be Related to Teething Remedies, F.D.A. Says. New York Times, October 18, 2016. www.nytimes.com/2016/10/19/health/teething-remedies-infant-deaths.html?_r=0 (Accessed on October 20, 2016).
- US Food & Drug Administration. Certain homeopathic teething products: FDA warning - Confirmed elevated levels of belladonna. http://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/ucm538687.htm (Accessed on January 30, 2017).
- US Food and Drug Administration. Homeopathic teething tablets and gels: FDA warning -- risk to infants and children. http://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/ucm523435.htm (Accessed on October 03, 2016).
- US Food and Drug Administration. Lidocaine Viscous: Drug Safety Communication- Boxed Warning Required - Should Not Be Used to Treat Teething Pain. www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/ucm402790.htm (Accessed on June 26, 2014).
- Questions & Answers: Reports of a rare, but serious and potentially fatal adverse effect with the use of over-the-counter (OTC) benzocaine gels and liquids applied to the gums or mouth www.fda.gov/Drugs/DrugSafety/ucm250029.htm (Accessed on August 03, 2012).
- FDA Consumer Updates. Benzocaine and Babies: Not a Good Mix. Available at: www.fda.gov/ForConsumers/ConsumerUpdates/ucm306062.htm (Accessed on August 03, 2012).
- Frazier-Bowers SA, Hendricks HM, Wright JT, et al. Novel mutations in PTH1R associated with primary failure of eruption and osteoarthritis. J Dent Res 2014; 93:134.
- COHEN MM, WINER RA. DENTAL AND FACIAL CHARACTERISTICS IN DOWN'S SYNDROME (MONGOLISM). J Dent Res 1965; 44:SUPPL:197.
- Wright JT. Challenges managing individuals with hereditary defects of the teeth. Seminars Orthodont 2016; 22:211.
- Bedoya MM, Park JH. A review of the diagnosis and management of impacted maxillary canines. J Am Dent Assoc 2009; 140:1485.
- Rasmussen P, Kotsaki A. Inherited primary failure of eruption in the primary dentition: report of five cases. ASDC J Dent Child 1997; 64:43.
- Jones KL. Appendix I: Pattern of malformation differential diagnosis by anomalies. In: Smith's Recognizable patterns of Human Malformation, 6th ed, Saunders, Philadelphia 2006. p.894.
- Harila-Kaera V, Heikkinen T, Alvesalo L. The eruption of permanent incisors and first molars in prematurely born children. Eur J Orthod 2003; 25:293.
- Pinheiro M, Snel AL, Freire-Maia N. Odontomicronychial ectodermal dysplasia. J Med Genet 1996; 33:230.
- Aldred MJ, Crawford PJ, Chadwick BL, et al. Precocious tooth eruption and loss in Letterer-Siwe disease. Br Dent J 1988; 165:367.
- Hilgers KK, Akridge M, Scheetz JP, Kinane DE. Childhood obesity and dental development. Pediatr Dent 2006; 28:18.
- Leroy R, Bogaerts K, Lesaffre E, Declerck D. The effect of fluorides and caries in primary teeth on permanent tooth emergence. Community Dent Oral Epidemiol 2003; 31:463.
- Lal S, Cheng B, Kaplan S, et al. Accelerated tooth eruption in children with diabetes mellitus. Pediatrics 2008; 121:e1139.
- Bohátka L, Wegner H, Adler P. Parameters of the mixed dentition in diabetic children. J Dent Res 1973; 52:131.
- Midtbø M, Halse A. Skeletal maturity, dental maturity, and eruption in young patients with Turner syndrome. Acta Odontol Scand 1992; 50:303.