When does the sphenoidal fontanelle close?

When does the sphenoidal fontanelle close?

• A. 2-3 months
• B. 1-3 years
• C. 6 months
• D. 6-8 months

Answer: (C)

The sphenoidal fontanelle closes relatively early as the skull bones ossify. It’s an anterolateral gap where the sphenoid bone meets surrounding bones, and it typically seals by about six months of age. This early closure reflects rapid ossification in that region as the skull matures to protect the growing brain. For context, the posterior fontanelle closes by around 2–3 months, and the anterior fontanelle by about 12–18 months, so six months is the common timeframe for the sphenoidal fontanelle.

The sphenoidal fontanelle closes relatively early as the skull bones ossify. It’s an anterolateral gap where the sphenoid bone meets surrounding bones, and it typically seals by about six months of age. This early closure reflects rapid ossification in that region as the skull matures to protect the growing brain. For context, the posterior fontanelle closes by around 2–3 months, and the anterior fontanelle by about 12–18 months, so six months is the common timeframe for the sphenoidal fontanelle.