What causes gum recession?

Gum recession is common and increases with age: around 50% of adults aged 18-64 and roughly 88% of people 65 and older have at least one site of recession (Kassab & Cohen, JADA).¹ In most people it reflects several causes acting together rather than a single one.

The five main contributors

Most clinical recession reflects a combination of the following factors, working over years to decades:

1. Thin periodontal phenotype (previously called thin biotype)

Some people are born with thin gum and thin overlying bone on the cheek-facing side of their teeth — a thin periodontal/gingival phenotype, the term the 2017/2018 World Workshop adopted in place of "biotype". The bone over the root may be less than 1 mm thick, sometimes with small natural windows where there is no bone at all (fenestrations). Once the thin tissue is challenged by brushing, inflammation, or orthodontic movement, it has very little to recover from.

Patients with prominent canines, narrow gum tissue between teeth, and visibility of root contour through the gum often have a thin phenotype. It is not a disease — it is an anatomical variation — but it is the substrate on which other factors act.

2. Brushing technique and brush firmness

Aggressive brushing with a hard brush and a horizontal scrubbing motion is widely regarded as a contributing factor, but the best available evidence — systematic reviews cited by the 2018 World Workshop consensus — finds the direct evidence that brushing alone causes recession to be inconclusive (Heasman et al.).³ It is best understood as one mechanical stressor acting on thin, susceptible tissue rather than a proven sole cause. Where it is involved, the pattern is typically symmetrical (the same teeth on both sides of the mouth) and concentrated on the canines and premolars in right-handed patients (or the opposite side in left-handed patients).²

The fix is technique change rather than stopping brushing — brushing is still essential. A soft brush, light pressure, and a small-circular or gentle-vibratory motion (or an oscillating powered brush) achieve plaque removal without traumatising the gum margin.

3. Periodontal disease

Severe periodontitis can present with recession as bone is lost. The pattern is often different from mechanical recession — it tends to be associated with bleeding, deeper pockets, and other signs of active gum disease. Addressing the periodontal disease must precede or accompany any surgical attempt to cover the recession.

The 2018 World Workshop consensus on mucogingival deformities discusses the interaction between periodontal disease and recession in detail.⁴

4. Orthodontic movement

Moving a tooth outside the bony envelope of the jaw — particularly moving a tooth labially (towards the lip) when the available bone is thin — predisposes the site to recession. This is one reason orthodontic planning increasingly includes assessment of gum and bone biotype, and why some cases benefit from gum augmentation before orthodontic treatment starts.

Recession that develops during or shortly after orthodontic treatment is sometimes a sign that the planned tooth movement exceeded what the underlying anatomy supported.

5. Habits and anatomical pulls

• Tongue thrust — pushing the tongue against the back of the front teeth during swallowing can contribute, especially in patients who do this frequently.
• Lip / cheek piercings — the constant mechanical contact between the metal stud and the gum is a well-recognised cause of localised recession in patients with oral piercings.
• Strong frenum attachments — the small bands of tissue connecting the lip or cheek to the gum can pull on the gum margin in some anatomical configurations.

Less common but worth knowing

A few less common causes:

• Self-induced — fingernails, pens, or other objects repeatedly inserted between gum and tooth.
• Smokeless tobacco placed habitually in the cheek pocket.
• Some medications can cause gum problems though usually as overgrowth rather than recession.
• Methamphetamine use — "meth mouth" is associated mainly with rampant tooth decay, dry mouth and periodontal breakdown, which can include gum recession.

How a specialist works out what caused yours

At the consultation, the periodontist asks about:

• Brushing technique and brush type (and may ask you to demonstrate).
• Any history of orthodontic treatment.
• Smoking and tobacco habits.
• Oral piercings (current or past).
• Family history of recession.
• Any history of gum disease.

And examines:

• The recession pattern (symmetrical? localised? generalised?).
• The thickness and quality of the existing gum tissue (biotype).
• The position of the muscle attachments.
• The bite and occlusion (some bite patterns load specific teeth and contribute to recession).
• Whether the recession is currently progressing or has been stable.

The causes drive the treatment plan. If you brush hard and the gum tissue is thin, brushing-technique change is part of the plan whether or not surgery is performed. If the recession is caused by periodontitis, the gum surgery must wait until the periodontitis is under control. If an orthodontic plan moved a tooth out of the bony envelope, the orthodontic plan needs revisiting.

What you can do today

Three things to start now if you have recession:

1. Switch to a soft-bristled brush. A soft brush, used with the right technique, removes plaque better than a hard brush used with poor technique — and it does not traumatise the tissue.
2. Use a gentle, small-circular brushing motion (or get a powered brush and let it do the work). Never a horizontal scrub.
3. Book a check-up. A periodontist or your general dentist can tell you whether your recession is stable or progressing, and which causes are active.

This article is general educational content. The combination of causes acting on your specific recession can only be established by examination.