Crown lengthening is a minor surgical procedure that exposes more of the tooth structure by removing a small amount of gum tissue and, in some cases, underlying bone. This gives the dentist more tooth to work with when placing a crown or other restoration.
Despite the name, the tooth itself does not become longer — more of the existing tooth is simply exposed above the gum line.
Why might I need crown lengthening?
Crown lengthening may be recommended for two main reasons:
Restorative (functional):
A tooth is broken off near or below the gum line due to fracture or decay
Not enough tooth structure is visible above the gum to support a crown without it becoming loose over time
The dentist needs to place the edge of a crown below the gum margin to protect a cavity or broken area — and enough space must exist between this margin and the bone
Cosmetic (aesthetic):
A "gummy smile" — too much gum shows when smiling because the teeth are partially covered
Uneven gum levels making the smile appear asymmetrical
What does the procedure involve?
Crown lengthening is carried out under local anaesthetic:
The area is numbed
Small incisions are made in the gum around the tooth or teeth being treated
The gum flap is gently lifted to expose the underlying bone
A small amount of gum tissue (and sometimes bone) is removed to create the required amount of exposed tooth structure
The gum is sutured back in its new position
There is typically a healing period of 6–8 weeks before the crown is fitted, to allow the gum level to stabilise.
Risks and possible complications
Common:
Swelling and soreness for several days after surgery
Teeth may appear longer after healing — this is expected
Tooth sensitivity, particularly to cold
Uncommon:
The final gum level may be slightly different to what was planned
Infection requiring antibiotics
Rare:
Compromised long-term support of the tooth if significant bone was removed
After crown lengthening
Take painkillers as recommended for the first few days
Eat soft foods on the opposite side
Rinse gently with warm salt water from day 2
An antiseptic mouthwash may be prescribed for 1–2 weeks
Sutures are usually removed at a follow-up appointment after 1–2 weeks
Avoid smoking to support healing
Questions to ask your dentist
Why is crown lengthening necessary before my crown can be placed?
How much longer will my tooth look after healing?
How long do I need to wait before the crown is fitted?
Could there be any long-term effects on the tooth or neighbouring teeth?
This leaflet is for general information only and does not replace professional dental advice. It is intended to support — not replace — the discussion with your dentist about your individual options, risks, and treatment plan. Treatment outcomes vary between patients depending on individual circumstances. Your dentist will confirm exact fees and what is suitable for your specific circumstances before you agree to any treatment.
When to Seek Urgent Help
If you develop heavy bleeding that does not settle or spreading swelling after crown lengthening, contact the practice immediately or go to A&E.
References
Aligned with guidance from: BSP (British Society of Periodontology), FGDP(UK), SDCEP.