Understanding the biological process of teething can help parents better manage their expectations and respond appropriately to their baby's needs.
Tooth Formation: Baby teeth actually begin forming during pregnancy, around the sixth week of gestation. By birth, all 20 primary teeth are already present beneath the gums, waiting to erupt. The crowns (visible parts) of these teeth are fully formed at birth, but the roots continue to develop as the teeth prepare to emerge.
The Eruption Process: When a tooth is ready to emerge, specialized cells called osteoclasts break down the bone tissue above the tooth, creating a path for eruption. Simultaneously, the tooth's root continues growing, pushing the crown upward through the gum tissue. This process causes inflammation and pressure, which is why babies experience discomfort.
Why It Hurts: The pain comes from the pressure of the tooth pushing through the gum tissue and the inflammatory response this triggers. The gums become swollen and tender as they stretch to accommodate the emerging tooth. Molars tend to cause more discomfort than incisors because they have a larger surface area and must break through more gum tissue.
Individual Variation: Genetics play a significant role in teething timing. If parents teethed early or late, their children are more likely to follow a similar pattern. Premature babies may teeth later than full-term babies when calculated from birth date, but typically follow a normal schedule when adjusted for gestational age.