How Does the Shape of the Head Change with Age? An Analysis of Cranial Remodeling

While the common belief is that the skull stops changing after puberty, recent research using 3D imaging reveals that significant, subtle remodeling occurs throughout life. Understanding how does the shape of the head change with age involves examining both the dramatic growth of infancy and the gradual bone resorption and thickening that alters the adult facial and cranial structure.

Quick Summary

The human skull undergoes continuous remodeling from infancy into adulthood, driven by brain growth and later, by bone resorption and deposition. Key changes include rapid cranial growth in childhood, the flattening and widening of eye sockets, midface recession, and changes to the mandible, which collectively alter facial proportions over time.

Key Points

• Two Phases of Change: The skull undergoes rapid growth in infancy and childhood, driven by brain expansion, before entering a slower phase of remodeling in adulthood.

• Bone Resorption is Key: In adults, age-related changes are primarily caused by selective bone resorption (loss) in the facial skeleton, particularly around the eye sockets, midface, and jaw.

• Eye Sockets Widen: The orbits (eye sockets) enlarge and widen with age due to bone resorption, contributing to a deep-set eye appearance and affecting eyelid position.

• Midface Recedes: The maxilla (upper jaw/mid-cheek area) recedes and loses projection, causing a loss of support for soft tissues and contributing to deeper nasolabial folds.

• Mandible Changes with Tooth Loss: The jawbone is significantly affected by tooth loss, leading to a reduction in its vertical height and a potential increase in the angle of the jaw.

• Thickening of the Cranial Vault: In contrast to facial bone loss, the inner table of the skull (cranial vault) can thicken with age, a condition that occurs more prominently in older women.

• Subtle Changes: While the skull doesn't visibly swell, the accumulation of these subtle bone remodeling processes creates noticeable shifts in overall facial proportions and appearance over a lifetime.

From Infancy to Adulthood: The Foundation of Skull Shape

In newborns, the skull is soft and flexible, with several separate bony plates connected by fibrous sutures and fontanelles. This structure accommodates brain growth and molds during birth. By around age two, the skull reaches about 80% of its adult size, and the fontanelles close.

Childhood skull development is primarily driven by brain expansion. The cranial sutures facilitate this growth by adding bone in response to pressure. This rapid growth phase slows around age 7, as the skull approaches adult size. However, the skull continues to change through a slower process of bone resorption and deposition that persists throughout adulthood.

Adult Cranial and Facial Remodeling

After the cranial sutures fuse in early adulthood, bone remodeling continues in a more targeted manner. This involves specific areas of bone loss (resorption) and, in some cases, bone addition.

Changes to the Upper Skull

The cranial vault undergoes less dramatic changes than the face in adulthood. A common alteration is the thickening of the inner frontal bone, particularly in older women, which can reduce intracranial volume. Some studies also suggest lateral widening of the outer cranial vault and compression in frontal and posterior areas.

Resorption and Widening of the Eye Sockets

The orbits are a key area of age-related change in the face. They increase in width and height due to bone resorption along the orbital rims, making the eyes appear more deep-set and contributing to eyelid changes. Resorption is most significant in the upper-inner and lower-outer portions of the rim.

Midface and Jawline Alterations

Midface changes significantly affect the aging facial appearance. The maxilla experiences substantial bone loss, reducing midfacial height and projection and diminishing support for soft tissues.

Key changes include:

• Midface retrusion: The shrinking and rotation of the maxilla can create a sunken midface.
• Deepening nasolabial folds: Bone loss around the nasal area can weaken tissue support, making the nose appear longer and nasolabial folds more prominent.
• Changes to the mandible: The jawbone is strongly influenced by aging, especially tooth loss. Tooth and associated bone loss reduces lower facial height, and the angle of the jaw may become more obtuse.

Comparison of Age-Related Skull Changes

Feature	Infancy & Childhood	Adulthood & Senior Years
Primary Driver	Rapid brain growth and expansion.	Selective bone resorption and deposition.
Sutures	Flexible and open to allow for skull expansion.	Fuse by early adulthood, restricting further expansion.
Facial Bones	Grow and project forward in all dimensions, establishing youthful proportions.	Undergo resorption, particularly in the midface and jaw, causing loss of projection.
Eye Sockets	Proportional to overall skull size.	Widen and enlarge due to orbital rim resorption.
Cranial Vault	Expands in response to brain growth; fontanelles close.	Inner table thickens (especially in females); some lateral expansion and frontal compression may occur.

Gender Differences in Skull Aging

Studies indicate variations in skull aging patterns between males and females.

Females

• Notable shape changes occur in the anterior and middle cranial fossae.
• Inner frontal compression and thickening are often more pronounced, particularly after menopause.
• Facial bone changes, including maxillary resorption, may manifest earlier.

Males

• Show significant changes in multiple cranial vault and cranial fossae areas.
• Inner and outer cranial vault regions exhibit distinct expansion and compression patterns.
• Skull bone density tends to be more consistent throughout life compared to females.

Conclusion: A Constantly Evolving Framework

In summary, the skull's shape changes throughout life through two main phases: rapid growth in childhood and continuous, gradual remodeling in adulthood. This adult remodeling primarily involves bone resorption in facial areas like the orbits and midface, and potential thickening in the cranial vault, leading to noticeable changes in appearance over time. It is a dynamic process that alters the bony framework, with the most visually significant changes occurring in the face due to shifts in underlying structure that affect soft tissue. Understanding this lifelong process provides valuable insight into the anatomy behind age-related changes in appearance.

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Frequently Asked Questions

At what age is your head shape considered fully permanent?

A person's head shape becomes mostly permanent by 18 to 24 months, as the skull bones fuse together. While significant growth ceases, subtle remodeling and facial bone changes continue throughout adulthood.

Do male and female skulls age differently?

Yes, studies show differences in skull aging between sexes. For example, adult females often experience greater thickening of the inner frontal skull table, while males show more significant shape changes across the cranial vault.

Can the skull get larger in adulthood?

True skull enlargement in adults is rare and often points to an underlying medical condition. Perceived changes in head size are more commonly the result of facial bone remodeling, such as widening eye sockets and jaw resorption, combined with soft tissue changes.

Does losing teeth change the shape of your head?

Yes, the loss of teeth, known as edentulism, significantly contributes to changes in facial structure. It leads to the resorption of the maxillary and mandibular vertical bone, reducing the height of the lower face and altering jaw shape.

What parts of the head change most with age?

The most significant age-related changes occur in the facial skeleton, particularly the orbits (eye sockets), midface (maxilla), and mandible (jaw). The cranial vault (upper skull) also undergoes more subtle remodeling, including inner table thickening.

How do facial bones change with age?

With aging, the facial bones, including the maxilla and mandible, lose density and recede. The eye sockets widen and the angle of the jaw can change. This loss of skeletal support causes soft tissues to drape differently, contributing to facial sagging and wrinkles.

Is it normal for a baby's head to be uneven?

Yes, it is common for a newborn's skull to be temporarily uneven or misshapen due to the pressures of birth. This often resolves within a few weeks. In some cases, persistent flattening, known as positional plagiocephaly, can occur but is generally correctable with repositioning or other therapies.