Newborn vs. Adult Skull: Key Differences in Size, Shape, and Structure

1. Size

• Newborn: Skull is about ¼ of total body length.
• Adult: Skull is about ⅛ of body length.

2. Shape

• Newborn: Rounder, larger cranium relative to face; prominent forehead; underdeveloped facial bones.
• Adult: More elongated and angular; smaller cranium relative to face; fully developed facial bones.

3. Fontanelles (Soft Spots)

• Newborn: Several fontanelles allow brain growth.
• Adult: Fontanelles closed; skull bones fused.

4. Sutures

• Newborn: Fibrous joints permit flexibility and growth.
• Adult: Mostly fused; a few remain slightly mobile.

5. Teeth

• Newborn: Typically no teeth.
• Adult: Full set of permanent teeth, including molars.

6. Sinuses

• Newborn: Not fully developed.
• Adult: Well-developed; contribute to voice resonance and facial structure.

These differences reflect developmental changes as the brain grows and the skull adapts.