Introduction

Have you ever noticed a crease that runs from the lower part of your nose to the corner of your mouth when you look at the mirror? The crease is called the nasolabial fold. The article below provides every information you need about nasolabial folds and how to manage it.

Nasolabial fold is a natural line or crease that runs from the side of the nose to the corner of the mouth. ‘Naso’ from nasal refers to the nose and ‘labia’ meaning lip, a fold between the nose and lip or the corner of the mouth. The crease appears on both sides of the face. They are also called smile or laugh lines because they become prominent when you smile or laugh. Although they are common to all people, the prominence of this line or crease comes with age due to depleting collagen and elastin levels, fat distribution, exposure to sun rays, smoking, repetitive facial movement and skin changes due to weight loss or gain. Nasolabial folds are more of a natural or common feature of the face rather than an abnormality. However, some people get uncomfortable when these creases or wrinkles become prominent as concavities or deepenings, as aging sets in. Nasolabial folds play a role in showing emotions, communication and also serve as one of the earliest signs of aging. 

Types of Nasolabial fold

The nasolabial fold shows significant variations among individuals, and it can be categorized into three primary groups.

• Concave type: the internal angle of the line is greater than 180°;
• Straight line type: the internal angle of the line is 180°;
• Convex type: the internal angle of the line is less than 180¹

Classification of nasolabial fold

Another way of classifying nasolabial fold is considering underlying structures which imparts the profundity of these folds. 

Bone retrusion class of nasolabial fold

Bone retrusion class of nasolabial fold, also called static nasolabial fold, is characterised by the retrusion of the upper jaw and cheek bones, which are the underlying bones of the nasolabial region of the face. The retrusion of these facial bones causes the overlying skin to wrinkle and sag, resulting in it caving in and the appearance of a profound fold. This class of nasolabial fold can manifest in anyone but it is common in people with receding upper jaw and cheek bones, which could be a result of reduction in bone density caused by aging or a number of other conditions.

Skin-quality class of nasolabial fold

Skin-quality class of nasolabial fold is a class of nasolabial fold which is subject to the quality of the skin of an individual. People with dry skin are susceptible to this class of nasolabial fold because dry skin is less elastic and cracks. Dry skin caves in due to lack of lubrication and moisturising effect of sebum (an oily and waxy substance produced bythe skin). Sensitive skins are also prone to developing prominent nasolabial folds owing to their prompt response to external stimuli such as particles or a change in temperature. Sensitive skins are easily irritated and inflamed causing the thinning of the skin and eventual damage. On the other hand, people with oily skin are advantaged due to the production of enough sebum for the lubrication and moisturising of their skin, reducing the cracking of skin and giving the skin a suppleness that allows it to maintain its integrity. 

Muscle-induced class of nasolabial fold

This class of nasolabial fold is also referred to as dynamic nasolabial fold. The frequent movement of underlying muscles during different facial expressions like laughing, smiling, frowning, chewing and others result in this type of nasolabial fold. The repetitive contraction of muscles in the nasolabial region of the face causes the appearance of wrinkles or creases. The repetitive movements or contractions of muscles that are involved in big facial expressions like scowling, smiling, eye-rolling and frowning are major contributors in the formation of profound nasolabial folds or specifically, muscle-induced class of nasolabial fold.

Fat-pad class of nasolabial fold

In this class of nasolabial fold, cheek fat distribution is responsible for the formation of nasolabial fold. As an individual ages, cheek fat thins out losing its volume resulting in the deepening of the creases and making the nasolabial fold more noticeable. This class of nasolabial fold is primarily influenced by the volume or thickness of the underlying cheek fat.  

Hybrid class of nasolabial fold

Hybrid class of nasolabial fold as its name implies is the combination of bone reclusion class of nasolabial fold (static nasolabial fold) and muscle-induced nasolabial fold (dynamic nasolabial fold). Reduction in facial fat volume, especially cheek fat thickness, is also a feature of this class of nasolabial fold. 

Causes of Nasolabial fold

Major causes of nasolabial fold include sun damage, aging and smoking. 

• Aging: as individuals age, skin’s collagen (a substance in the body which keeps your skin from sagging, giving you that plump, youthful look) and elastin, responsible for the skin’s elasticity and strength, degrade, making the nasolabial fold prominent. The different fat distribution in the face that occurs when you age causes the absence of fat in some regions of the face making nasolabial fold prominent. 
• Sun damage: exposure to ultraviolet rays from sunlight causes the degradation of the skin’s collagen and elastin, making the nasolabial fold more prominent because of the looseness or sagging of the skin.
• Smoking: leads to increased production of enzymes responsible for breaking down collagen resulting in reduction of the skin’s elasticity.
• Genetics: some individuals may have skin with depleted collagen levels resulting in skin with reduced elasticity because of genetics.

Other causes include:

• Repetitive facial expression 
• Sleeping positions
• Radiation from electronic devices and air pollution

How to reduce the risks of having nasolabial fold?

• Wearing sunscreen: wear sunscreen to reduce the exposure of the skin of the face to sunlight.
• Smoking: do not smoke or quit smoking if you smoke, to avoid sagging of skin due to collagen breakdown.
• Healthy diet: eat healthy food to keep your body healthy. The healthier you are, the healthier your skin appears.
• Exercise: exercise increases blood circulation to the skin. This keeps the skin healthy.
• Usage of moisturising skin care products: moisturising skin care products help keep the skin moisturised, maintaining the quality of the skin.
• Sleeping posture: sleeping on your back prevents gravity from pulling down loose skin in your cheekbone area, thereby preventing the prominence of the nasolabial fold. Sleeping on your side or on your chest allows gravity to tug loose skin around your cheekbone making nasolabial fold more pronounced.

What are the treatments available for nasolabial fold?

Nasolabial folds are a part of the human facial anatomy and their conspicuity is inevitable as an individual ages. However, the profundity can be reduced through different methods which includes:

• Use of skin care products: containing minerals and vitamins responsible for skin rejuvenation and enhancement of skin quality can slow down the rate at which nasolabial prominence progresses as an individual ages.
• Use of Botox injections: Botulinum toxin injection, also more commonly known as  Botox, acts by preventing nerve cells from releasing acetylcholine (a chemical substance which causes muscles to contract), resulting in a temporary paralysis of facial muscles. This procedure limits the contraction of facial muscles preventing the manifestation of the dynamic class of nasolabial fold. The effect of the injection wears out between three to six months, after which the injection will be given again. This procedure is carried out by an experienced surgeon with expertise in cosmetic surgery.
• Application of dermal fillers: dermal fillers are liquid substances which fill the skin around the cheek area, add to the volume and lift the area of the cheek. The use of specific fillers depend solely on the severity or profundity of the nasolabial fold. Common dermal fillers include hyaluronic acid, calcium hydroxyapatite and polylactic acid.²
• Use of skin tightening procedure: in cases where skin looseness is the cause of prominent nasolabial fold, skin tightening procedure can be used. The procedure uses ultrasound or fractional laser to destroy the layer of skin just beneath the top layer to allow for the regrowth of collagen for tiger and thicker skins.
• Surgery: this involves a full face-lift or a cheek lift done by a cosmetic surgeon, to help reduce the appearance of the nasolabial fold.

Benefits of nasolabial treatment

• Improved facial appearance: nasolabial treatments like non-invasive dermal fillers, surgery, use of botox improve facial appearance by reducing the prominence of the creases and wrinkles around the nose and mouth giving the face a refreshing and youthful impression.
• Restored facial volume: nasolabial treatment restores cheek or mid-face volume reducing the effect of age-related loss of mid-face or cheek volume.
• Enhanced confidence: treatment boosts self-confidence and self-esteem as individuals are pleased with their facial health and refreshing look.
• Functional benefit: nasolabial treatment may sometimes improve oral function by reducing nasolabial groove and creases, making speaking, smiling and eating easier, improving the overall oral health.

Risks of nasolabial fold treatments

Although nasolabial treatments are generally safe when performed by a trained and qualified medical professional, they do carry certain risks and potential side effects, including:

• Bruising: Bruising at the injection site is a common side effect. It usually resolves within a few days to a week but can be more pronounced in some individuals.
• Swelling: Swelling is another common side effect, especially immediately after the procedure. It typically subsides within a few days, but in some cases, it may last longer.
• Redness: Redness at the injection site can occur but usually resolves within a few days.
• Pain or Discomfort: Some patients may experience mild pain or discomfort at the injection site, which can be managed with pain relievers if necessary.
• Allergic Reactions: While rare, some individuals may be allergic to the ingredients in dermal fillers. It's essential to inform your healthcare provider of any allergies or sensitivities before the procedure.
• Infection: There is a risk of infection associated with any injection-based cosmetic procedure or surgery. It's crucial to choose a qualified and reputable provider who follows proper sterile techniques to minimize this risk.
• Lumps or Bumps: Occasionally, dermal fillers can lead to the formation of lumps or bumps under the skin. These can often be massaged out or may require additional treatment to resolve.
• Asymmetry: Achieving perfect symmetry can be challenging, and there's a risk that the results may not be entirely symmetrical. This risk can be minimized by choosing an experienced injector.
• Vascular Complications: Although extremely rare, injecting dermal fillers in the wrong location can lead to vascular complications, including blockage or narrowing of blood vessels. This can have severe consequences and may require emergency medical attention.

To minimize the risks associated with nasolabial fold treatments, it is essential to consult with a board-certified and experienced healthcare provider who can evaluate your individual needs, discuss potential side effects, and develop a treatment plan tailored to your goals while ensuring safety. Additionally, be sure to provide your medical history, allergies, and any medications you are taking to your provider to reduce the risk of complications.^3,4,5

Summary

In conclusion, the nasolabial fold is a natural part of the facial anatomy, playing a role in expressions and communication while also serving as an early indicator of aging. Understanding its’ types and causes helps individuals make informed choices about treatment options. Various treatments, including dermal fillers, Botox injections, and surgery, offer benefits such as improved facial appearance and boosted confidence. However, these treatments are not without risks, including bruising, swelling, and the possibility of allergic reactions or infections. To minimize these risks, it's crucial to consult with qualified professionals and consider non-invasive options first, ensuring that the chosen treatment aligns with individual goals and concerns regarding nasolabial folds.