An odontogenic keratocyst is a noncancerous growth hidden inside the jawbone, usually found by chance on a dental X-ray. It is removed with surgery, and most people keep their jaw and face as they were. But it behaves more stubbornly than an ordinary cyst, which is why treatment aims as much at stopping it returning as at removing it.
Where It Comes From and Where It Grows
The growth forms from tiny leftover cells of the tissue that shaped your teeth before birth.1Journal of Oral & Dental Health. Odontogenic Keratocyst in Anterior Mandible: A Case Report That makes it a developmental growth, not something caused by infection or anything you did.2Journal of Oral & Dental Health. Odontogenic Keratocyst in Anterior Mandible: A Case Report In many keratocysts the cells also carry a change in a growth-control gene that leaves a “grow” signal switched on.3Journal of Dentomaxillofacial Science. Molecular pathways of odontogenic keratocysts: A systematic review That signal helps explain why it tends to return.4PubMed. PTCH1 mutations in odontogenic keratocysts: are they related to epithelial cell proliferation?
The name comes from the lining, which makes keratin, the same tough protein found in skin and nails. Instead of clear fluid, the cyst fills with a soft, cheesy material made of it. The lining is also the part surgeons must remove completely.
It is not cancer, and it does not spread to other organs. Left untreated, though, it can keep enlarging and hollow out the bone. Turning cancerous is very rare, but it is one reason doctors examine the removed tissue.
It occurs about twice as often in the lower jaw as the upper.5PubMed Central. Odontogenic keratocyst: imaging features of a benign lesion with an aggressive behaviour In the lower jaw it favours the back, near the angle and the upright part behind the last molars.6PubMed Central. Odontogenic keratocyst: imaging features of a benign lesion with an aggressive behaviour In the upper jaw it more often appears near the canine or the wisdom-tooth area.7PubMed Central. Odontogenic keratocyst: imaging features of a benign lesion with an aggressive behaviour
How It Is Found and Confirmed
On an X-ray it looks like a dark, well-outlined hollow in the bone.8PubMed Central. Imaging Characteristic of 11 Lesions of Odontogenic Keratocyst in the Indian Subpopulation: A Cone-Beam Computed Tomography Experience It can be a small single pocket or a large one with several chambers.9PubMed Central. Imaging Characteristic of 11 Lesions of Odontogenic Keratocyst in the Indian Subpopulation: A Cone-Beam Computed Tomography Experience Many people have no symptoms at all until an X-ray happens to find it. Larger ones can swell the jaw or cheek, loosen or shift a tooth, or cause drainage and a bad taste if infected. If the cyst presses on a nerve, the lip can go numb.
The picture looks similar to other jaw cysts and tumours, so the X-ray alone cannot name it.10PubMed Central. Imaging Characteristic of 11 Lesions of Odontogenic Keratocyst in the Indian Subpopulation: A Cone-Beam Computed Tomography Experience One clue is that, compared with ameloblastoma, its closest look-alike, it pushes on tooth roots less often, about 1 in 7 cases versus half.11PubMed Central. Three-Dimensional Radiographic and Morphological Features of Ameloblastoma and Odontogenic Keratocyst: A Comparative Cone Beam Computed Tomography Study Using Automatic Segmentation A 3D dental scan, called a cone-beam CT, shows the cyst’s shape and how close it lies to nerves.
The diagnosis is made by examining a small tissue sample under a microscope.12PubMed Central. Odontogenic keratocysts: A retrospective histopathological study Pathologists recognise the lining by its typical thin, wavy, keratin-making layer.13PubMed Central. Odontogenic keratocysts: A retrospective histopathological study
The biopsy is done under local anaesthetic in the surgeon’s chair. The surgeon opens a small window in the gum and takes a piece of the lining. Results usually take about a week or so.
Surgery to Remove the Cyst
The standard operation scoops out the whole cyst lining in one piece. Surgeons often also burr away a thin rim of the surrounding bone to catch leftover cells.14PubMed Central. Recurrence rate of odontogenic keratocyst treated by enucleation and peripheral ostectomy: Retrospective case series with up to 12 years of follow-up With this approach about 1 in 7 cysts came back over a typical 5 years of follow-up.15PubMed Central. Recurrence rate of odontogenic keratocyst treated by enucleation and peripheral ostectomy: Retrospective case series with up to 12 years of follow-up In the upper jaw, about 1 in 10 recurred, some as late as 14 years after surgery.16PubMed Central. Comparison of Recurrence Rates of Odontogenic Keratocyst and Ameloblastoma following surgical excision and peripheral ostectomy in the Maxilla
Getting the lining out whole is harder than it sounds. A keratocyst lining is unusually thin and fragile, so it can tear into fragments as it is lifted from the bone, and any fragment left behind can regrow into a new cyst. It is also less firmly attached than in some other cysts, so the surgeon works slowly with small instruments to separate it from the bone and from nearby nerves.
Small cysts may be removed in the office, while large ones need general anaesthesia. Expect swelling and soreness for several days, eased by cold packs and painkillers. Plan on soft food and careful rinsing for the first week or two. The hollow refills with new bone gradually over months.
Teeth sitting inside the cyst may need to come out, because keeping them can leave cells behind and raise the chance of return. Ask your surgeon before the operation which teeth are at risk.
Removing a section of jawbone is reserved for aggressive cases.17PubMed Central. Clinical indications for radical resection of odontogenic keratocyst: A systematic review These include cysts larger than 5 cm in the back of the lower jaw with several chambers, cysts that have come back several times despite gentler surgery, and ones that have broken through into the sinus or surrounding tissues.18PubMed Central. Clinical indications for radical resection of odontogenic keratocyst: A systematic review Most people will not need this.
Shrinking a Large Cyst First
Decompression means placing a small tube or opening so the cyst drains and pressure drops. The bone around it can then refill and the cyst gets smaller. You rinse the tube daily with saline or water using a syringe, and checkups every few weeks track the shrinkage on X-ray. During this time the lining also becomes thicker and tougher.19PubMed. Decompression of keratocystic odontogenic tumors leading to increased fibrosis, but without any change in epithelial proliferation In one group, after about 7 to 9 months most linings no longer looked like keratocyst tissue.20PubMed. Dedifferentiation of odontogenic keratocyst epithelium after cyst decompression
Even so, the lining’s growth activity does not drop with the shrinking step,21PubMed Central. Decompression induces inflammation but do not modify cell proliferation and apoptosis in odontogenic keratocyst and small extra pocket cysts can even become more common afterwards.22PubMed. Decompression of keratocystic odontogenic tumors leading to increased fibrosis, but without any change in epithelial proliferation So surgeons usually remove the shrunken cyst in a second operation.
Some people choose this route over one big operation because it can save nearby teeth and nerves and lowers the risk of breaking a thinned jaw. The trade-off is months of care and two procedures.
Chemical Treatments That Lower the Chance of Return
Carnoy’s solution is a strong chemical briefly applied to the bone cavity after removal.23PubMed Central. Carnoy’s solution in the mangement of odontogenic keratocyst It kills a thin surface layer of cells that may have been left behind.24PubMed Central. Carnoy’s solution in the mangement of odontogenic keratocyst The surgeon first scoops out the cyst, then paints or packs the solution into the empty cavity for a short, timed period before rinsing it out. The gum is protected, because the chemical damages any living tissue it touches. It soaks into bone only a very short depth, so it is meant to catch stray cells on the surface, not to treat a cyst left in place.
The original and a modified version work about equally, with recurrence near 1 in 10 for both.25PubMed Central. Modified Carnoy’s Versus Carnoy’s Solution in the Management of Odontogenic Keratocysts—A Single Center Experience One study, however, found no clear benefit over simple removal.26Journal of Oral Medicine and Oral Surgery. Factors influencing the recurrence of keratocysts: monocentric study
Another option packs the cavity with 5-fluorouracil (5-FU), a cancer-treatment cream, after surgery.27PubMed Central. The Role of 5-Fluorouracil in Preventing Recurrence After Enucleation of Odontogenic Keratocyst: A Case Report One method uses soaked gauze removed after 24 hours,28PubMed Central. The Role of 5-Fluorouracil in Preventing Recurrence After Enucleation of Odontogenic Keratocyst: A Case Report and a newer one uses a dissolving sponge, so nothing needs removing.29PubMed. Refined Topical 5-Fluorouracil Technique for the Targeted Treatment of Odontogenic Keratocysts In pooled results from a limited number of studies, no recurrences occurred with 5-FU, compared with about 1 in 4 with modified Carnoy’s.30PubMed. Comparing 5-Fluorouracil Versus Modified Carnoy’s Solution for the Treatment of Odontogenic Keratocysts: A Systematic Review and Meta-Analysis Permanent numbness from nerve injury was about 7% with 5-FU versus 18% with modified Carnoy’s.31PubMed. Comparing 5-Fluorouracil Versus Modified Carnoy’s Solution for the Treatment of Odontogenic Keratocysts: A Systematic Review and Meta-Analysis Since 5-FU is newer, long-term results are still building.
Why It Comes Back and Who Is at Higher Risk
Cysts with several chambers or extra satellite pockets return more often.32PubMed Central. Recurrence and Prognosticators of Recurrence in Odontogenic Keratocyst of the Jaws So do cysts that broke through the outer bone or into soft tissue.33PubMed Central. Recurrence and Prognosticators of Recurrence in Odontogenic Keratocyst of the Jaws Larger cysts and younger patients also carry higher risk.34PubMed Central. Factors and management techniques in odontogenic keratocysts: a systematic review Gene changes that keep the cells growing are linked to more recurrence-prone cysts too.35PubMed. PTCH1 mutations in odontogenic keratocysts: are they related to epithelial cell proliferation?
Perforation means the cyst has worn through the outer wall of the jawbone and is in contact with the gum or other soft tissue, which makes complete removal harder. A scan before surgery can show whether this has happened, so the surgeon can plan a more thorough removal.
A returning cyst is not cancer and is usually treated again with surgery. It is often found early on routine X-rays, before any symptoms. Ask your surgeon how your cyst’s features rate for risk.
Follow-Up X-Rays for Years Afterwards
A follow-up period of about 10 years is recommended.36PubMed Central. Appropriate follow-up period for odontogenic keratocyst: a retrospective study One suggested plan is a yearly panoramic dental X-ray,37PubMed Central. Protocol for management of odontogenic keratocysts considering recurrence according to treatment methods and the same plan adds an MRI scan every 2 years to catch early returns.38PubMed Central. Protocol for management of odontogenic keratocysts considering recurrence according to treatment methods Anyone who has had a recurrence needs closer checking.39PubMed Central. Appropriate follow-up period for odontogenic keratocyst: a retrospective study
At a visit, the surgeon or dentist reviews a panoramic X-ray, a single wide image of both jaws taken while you stand still for a short scan. They compare it with your earlier images, looking for a new dark area in or near the old surgical site.
Set yearly reminders and keep copies of old X-rays. Report new swelling, loose teeth, or numbness between visits. If you move, ask for your records to be sent to a new surgeon.
Multiple Cysts and Gorlin Syndrome
Gorlin syndrome is an inherited condition causing jaw keratocysts and many skin basal cell cancers.40PubMed Central. Gorlin-Goltz syndrome Keratocysts are often its first sign, in about 78% of cases in one series,41PubMed Central. Gorlin-Goltz syndrome and they can appear before age 10.42PubMed Central. Gorlin-Goltz syndrome In the syndrome they are often multiple and large, sometimes changing the shape of the face.43PubMed Central. Multiple jaw cysts-unveiling the Gorlin-Goltz syndrome
Doctors look for other signs too:
- Basal cell skin cancers, many or one before age 2044PubMed Central. Gorlin-Goltz syndrome
- Three or more small pits on the palms or soles45PubMed Central. Gorlin-Goltz syndrome
- Calcium deposits in a brain membrane seen on scans46PubMed Central. Gorlin-Goltz syndrome
- Forked or fused ribs47PubMed Central. Gorlin-Goltz syndrome
- A parent, sibling, or child with the syndrome48PubMed Central. Gorlin-Goltz syndrome
In Gorlin syndrome, vismodegib, a pill blocking the same overactive growth signal, can help when surgery is not possible.49PubMed Central. Vismodegib hedgehog-signaling inhibition and treatment of basal cell carcinomas as well as keratocystic odontogenic tumors in Gorlin syndrome This applies to a small group, not typical single cysts.
Ask about the syndrome if you have more than one cyst or had one as a child. If it is diagnosed, skin checks with a dermatologist are worthwhile, and sun protection matters because skin cancers are common. Relatives may benefit from screening or genetic counselling.
Chewing, Teeth and Life After Treatment
How well you chew after surgery depends on how many teeth were lost.50PubMed. Effects of mandibular odontogenic keratocyst surgery and removable partial prostheses on masticatory performance Bigger operations remove more teeth, so a removable partial denture can improve chewing when several are lost.51PubMed. Effects of mandibular odontogenic keratocyst surgery and removable partial prostheses on masticatory performance
Dentures can be fitted once the area heals. Implants may be possible once new bone has filled in, and bone grafts are sometimes needed after larger operations. Your surgeon and dentist plan this together.
Lip or chin numbness can follow surgery near the jaw nerve. It often improves over months but can be permanent, so tell your surgeon early about any change.