Ins and outs

Cutaneous ageing is caused by two distinct processes - intrinsic and extrinsic factors. Intrinsic, or chronological ageing, is the inevitable genetically determined process that naturally occurs. Intrinsic ageing is determined by our genetic clock and is affected by the degenerative effects 
of free radicals and the body's inability to perfectly repair their damage.

Over time our cells, tissues and vital organs ‘rust' or deteriorate. These internal changes to the muscle, fat and bones are not as visible as the signs of ageing on the external organ - our skin. Our skin shows the wear and tear of extrinsic ageing, which is environmentally induced and manifests in age-associated skin changes including thinning, laxity, fragility and wrinkles. In addition, sun-exposure leads to dyspigmentation, premature wrinkling, telangiectasia 
and actinic elastosis.

Intrinsic ageing is a continuous process that usually begins in our mid-20s but doesn't become evident for decades. In our 20s collagen production begins to slow and elastin has a bit less spring. Dead skin cells do not shed as quickly and turnover of new skin cells decreases.

The apparent signs of intrinsic ageing include the loss and descent of underlying fat leading to hollowed cheeks and eye sockets, as well as loss of firmness and sagging skin as the bones shrink away from the skin due to bone loss.

Genes control how quickly the normal ageing process unfolds. At a cellular level, ageing is thought to be related to the shortening of telomeres (the terminal portions of chromosomes) with each cell cycle, resulting in cell-cycle arrest or apoptosis once a critical length is reached.

The extrinsic, or preventable environmental factors that magnify intrinsic ageing, often act together with the normal ageing process to prematurely age our skin. Most premature ageing is caused by sun exposure, though others are repetitive facial expressions, gravity, sleeping positions and smoking.

Lines and creases form over major and minor joints, as a result of skin contractions that lie perpendicular to the underlying muscular vector force. However, relaxed skin tension lines (RSTL) are formed during relaxation and are created by the natural tension on the skin from the underlying structures.

Structural changes

Recent studies have shown that shrinking of facial bones also plays a role in ageing the face. Evidently, facial bones remodel their three-dimensional shape with age, showing the most pronounced difference measured in the T-zone.

In women, the area between the brows and top of the nose (the glabellar angle) is shown to decrease as the area under the rim of the eyebrows retreats, resulting in sagging brows and deflated eyelid skin. In men, the glabellar angle decreases and the area supporting the cheeks (maxillary angle) is also shown to decrease.

Additionally, the malar fat pad, which is responsible 
for cheek fullness, slides down and forward, pushing against the nasolabial fold and making the maxillary angle appear more pronounced. Bones can also recede in the pyriform angle (the opening of the nose), causing the appearance of an elongated nose and a drooping nasal tip.

Volumetrics

A good way to assess the changing forms of ageing is to divide the face into the upper third (forehead and brows), middle third (mid-face and nose), and lower third (chin, jawline and neck).

The mid-face is important in facial aesthetics because perceptions of beauty are found largely in the synergy between the eyes, nose, lips and cheekbones (central facial triangle). This area should be considered from a three-dimensional rather than two-dimensional perspective when aiming to recreate more youthful contours and fullness.

In recent years there has been a marked increase in the number of surgical and non-surgical procedures aimed at repositioning facial fat and tissue and restoring lost facial volume to create a natural-looking, younger appearance.

Changes of the ageing face explained

Although every face ages differently, there are three common themes noted in all ageing faces.

As we age, facial fat descends and causes the shape of our face to change. The youthful face is typified by full, well-supported fat, and surrounding ligaments serve to fixate this volume of fat to underlying structure.

In middle age, as this ligament support reduces, facial fat volumetrically comes forward and descends in the cheek, producing a squarer facial contour with less distinction between upper cheek volume and mid-facial fat. This lowering of the facial fat means that over time our face appears vertically longer than young faces.
The deflation of facial volume is most apparent in regions with a high density of retaining ligaments, which are typically volumetrically full in youth. Along with facial deflation comes a laxity in soft tissue caused by diminished support.

Facial ageing is not all vertical - the soft tissue that occurs along specific areas of the mid-face also undergoes radial expansion. Over time the expressions we make with our faces cause the skin along the nasolabial line to disrupt the subcutaneous fat, disrupting the attachments between the fat and facial fascia.

Ageing gracefully

While a large part of the ageing process is predetermined by genetics, skin type and lifestyle, the ageing process can be reduced by recognising healthy lifestyle factors such as sun protection, a healthy diet and exercise regime, and effective management of stress. Taking a proactive approach can have you feeling that age is indeed just a number.