Tannutviklingen

Tannutviklingen, or tooth development, is the biological process by which teeth form, mature, and function. In humans it begins during fetal life and continues into early childhood, with additional remodeling that yields the permanent dentition. The process depends on interactions between the oral epithelium, derived from ectoderm, and the underlying neural crest–derived mesenchyme.

Development proceeds through a sequence of stages starting with the dental lamina forming along the jaws. This gives rise to tooth buds that pass through bud, cap, and bell stages. The enamel organ, derived from epithelium, forms enamel, while the dental papilla, derived from mesenchyme, produces dentin and pulp. The roots form later under the influence of Hertwig’s epithelial root sheath, with mineralization completing the mature tooth.

Eruption follows crown formation: primary teeth typically emerge between about 6 and 30 months of age, while permanent teeth begin development prenatally and continue erupting through adolescence. Timing varies among individuals and populations.

Genetic regulation is central to odontogenesis. Mutations in genes such as PAX9, MSX1, and SHH can cause tooth agenesis or other anomalies; environmental factors and systemic conditions can also affect tooth formation and eruption.

Clinical relevance lies in diagnosing and managing anomalies such as hypodontia, anodontia, enamel defects, or dentinogenesis imperfecta. Understanding tannutviklingen informs pediatric and orthodontic care, helps predict eruption patterns, and guides treatment planning. Across mammals, the basic framework of tooth development is conserved but differs in timing and dentition.