odontogenic keratocyst or keratocystic odontogengic tumor. it is always in dicussion due to its high recurrunce rate and presence of daughter cyst.

1. CASE PRESENTATION
ODONTOGENIC
KERTOCYST
Presented by- Dr. Sujay Patil
Dept of maxillofacial surgery

2. PATIENT DETAILS
• 35 year old Female reported
to BVP OPD with C/C/O
swelling in lower right back
tooth region since 6
months.
• Swelling was gradually
increased in last 3 months.
• It was not associated with
pain.

3. ON EXAMINATION
• Swelling with 42 to 46.
• It was firm.
• Intra oral bulge on buccal side
was present.
• Missing 45.
• No loss of sensation.

4. INVESTIGATIONS
• Complete heamogram
• Routine urine
• Blood glucose level- Random
• Serum electrolyte
• Serum creatinine
• HIV/ HBsAg antigen test
• PT-INR
• OPG
• CBCT

5. RADIOGRAPHIC EXAMINATION

10. HISTOLOGIC EXAMINATION

12. PROVISIONAL DIAGNOSIS
On the basis of the patient’s history and the clinical
radiographic and histological findings, a provisional
diagnosis of Benign cyst was made.

13. Treatment Plan
• RCT 43, 44 and 46.
• Placement of an lower arch bar.
• Enucleation with open dressing.

15. INTRA OPERATIVE

16. •Painting and draping done in usual manner
•LA infiltrated in lower right vestibule.

17. •Vestibular degloving incision
•Dissection done
•Corticotomy done
•Cyst exposed

20. MICROSCOPIC EXAMINATION

22. DIAGNOSIS

23. • Odontogenic Kerato-Cyst.

24. POST OPERATIVE

26. POSTOPERATIVE OBSERVATION

27. • Postoperative recovery was uneventful.
• Healing progressed satisfactorily.
• 2 months after we removed arch bar as bone healing
appears satisfactory.
• In view of these satisfactory findings no further
surgical intervention was considered necessary, and
it was decided to examine the patient periodically.

28. DISCUSSION

29. INTRODUCTION
• Kramer (1974) has defined a cyst as ‘a pathological
cavity having fluid, semifluid or gaseous contents and
which is not created by the accumulation of pus’.
Most cysts, but not all, are lined by epithelium.
• Odontogenic keratocyst is a distinctive form of
developmental odontogenic cyst.
• Odontogenic keratocysts (OKCs) are known for their
propensity to recur.

30. Various terminologies
• cholesteatoma (Hauer, 1926; Kostecka, 1929)
• ‘odontogenic keratocyst’ was introduced by Philipsen (1956).
• ‘primordial cyst’ (Shear, 1960a; Shear and Altini, 1976; Pindborg et al.,
1971)
• ‘keratocystoma’ (2003, Shear)
• ‘keratinising cystic odontogenic tumour’ (Reichart and Philipsen, 2004)
• ‘keratocystic odontogenic tumour’ (Philipsen, 2005)
• “keratocystic odontogenic tumor.”(latest WHO classification of odontogenic
tumors)

31. Etiology and Pathogenesis
• The etiology is probably closely related to the development of the
dental lamina and in particular remnants of it after this organ has
served its purpose.
• OKCs that occur in the dentate areas of both the maxilla and
mandible probably derive from those remnants.
• Epithelial islands that are derived from the dental lamina are mainly
found in the gingiva and periodontal ligament.
• It is not known why it develop from such epithelial residues or
epithelial island.
• The result of increased osmotic pressure within the lumen of the
cyst. This mechanism does not appear to hold true for odontogenic
keratocysts, and their growth may be related to unknown factors
inherent in the epithelium itself or enzymatic activity in the fibrous
wall.

32. • There is plenty of evidence that the majority of epithelial
islands, as found in the wall of OKCs, are in fact located in the
mucosa that is overlying the OKC and attached to it.
• This is the reason why it is thought that offshoots of the basal
layer of the epithelium of the oral mucosa may also be
involved in the etiology of OKCs.
• Epithelial islands and/or microcysts are found in
approximately 50% of the cases in the overlying, attached
mucosa.
• If one removes such an OKC some of these epithelial residues
may be left behind which may later give rise to a new
keratocyst.

33. odontogenic keratocysts make up 3% to 11% of all odontogenic cysts.

34. Clinical presentation
• Age between 10 and 40 years.
• Slight male predilection.
• The mandible is involved in 60% to 80% of cases, with a
marked tendency to involve the posterior body and ascending
ramus.
clinical types
small
unilocular cyst in the
dentate area that often
presents as a lateral
periodontal or lateral
follicular cyst
large
often multilobular or
multilocular cyst in the
posterior maxilla or
angle and ascending
ramus of the mandible

35. • Tend to grow in an anteroposterior direction within the medullary
cavity of the bone without causing obvious bone expansion.
• Multiple odontogenic keratocysts may be present - the nevoid
basal cell carcinoma (Gorlin) syndrome.
• It demonstrates a well-defined radiolucent area with smooth and
often corticated margins.
• An unerupted tooth is involved in the lesion in 25% to 40% of cases
- the cyst has presumably arisen from dental lamina rests near an
unerupted tooth and has grown to envelop the unerupted tooth.
• Resorption of the roots of erupted teeth adjacent to it is less
common.

36. Histopathological features
• Cystic lumen may contain a clear liquid that is similar to a
transudate of serum, or it may be filled with a cheesy
material, consists of keratinaceous debris.
• Thin fibrous wall is devoid of any inflammatory infiltrate.
• Epithelial lining is composed of a uniform layer of stratified
squamous epithelium, usually six to eight cells in thickness.
• Epithelium and connective tissue interface is usually flat, and
rete ridge formation is inconspicuous.
• Detachment of portions of the cyst-lining epithelium from the
fibrous wall is commonly observed.

37. • The luminal surface shows
flattened parakeratotic epithelial
cells, which exhibit a wavy or
corrugated appearance.
• Small satellite cysts, cords, or
islands of odontogenic epithelium
may be seen within the fibrous
wall(7% to 26% of cases in various
reported series).
• Orthokeratinizing cysts - Some
investigators recognize as a
microscopic variant and include this
lesion as a subtype.
• KCA – Kunnas et al 1986

38. Recurrence
• Recurrence rate of approximately 30%.
• More often in mandibular odontogenic keratocysts,
particularly those in the posterior body and ascending ramus.
• Recur within 5 years of the original surgery
• Many surgeons recommend
1. peripheral ostectomy of the bony cavity with a bone bur to
reduce the frequency of recurrence.
2. chemical cauterization of the bony cavity with Carnoy’s
solution after cyst removal.

39. Reasones???
• Tendency to multiplicity.
• Occurrence of satellite cysts which may be retained during an
enucleation procedure.
• Linings are very thin and fragile, particularly when the cysts
are large.
• Innate tendency to develop such cysts, then any remnants of
dental lamina may form the target for new OKC
formation.{Soskolne and Shear (1967)}
• OKCs may also arise from proliferations of the basal cells of
the oral mucosa, particularly in the third molar region and
ascending ramus of the mandible.{Stoelinga (1971a, 2001,
2003a) and Stoelinga and Peters (1973)}

40. TREATMENT

41. • It is important to keep in mind the possible reasons of
recurrence.
• Treatment should aim at elimination of possible vital cells left
behind in the defect - from the original lining or derived from
microcysts in the wall.
• The choice of treatment approach should be based on the size
of the cyst, recurrence status, and radiographic evidence of
cortical perforation.

42. • Enucleation followed by open packing.
• The resulting cavity was irrigated with mixture of normal
saline + chlorhexidine gluconate for a full-of glass.
• Packed with iodoform gauze impregnated with bacitracin
ointment to minimize the risk of recurrence in each recall
visits.
• The benefit of this protocol lies in the minimal surgical
morbidity, associated structures such as the inferior alveolar
nerve and developing teeth are less vulnerable to the
damage.

43. • Marsupialisation with open dressing.
• Continuous irrigation and packing with iodoform gauze
dressing.
• After 10 months enucleation.

44. • Brondum and Jensen(1992)
and Marker et al(1997).
• After cystotomy and incisional
biopsy, some surgeons have
treated it by insertion of a
polyethylene drainage tube to
allow decompression and
subsequent reduction in size of
the cystic cavity.
• It results in thickening of the
cyst lining, allowing easier
removal with an apparently
lower recurrence rate.
• Disadvantages - it requires two
surgical procedures and the
treatment time necessary is
comparatively long.

45. • Instead of the use of Carnoy’s solution, liquid nitrogen
1. Used to freeze the defect.
2. Much more complicated.
3. Indicated in selected patients.
• Block resection, with or without preservation of the continuity
of the jaw.
1. Drastic method - considerable morbidity
2. Reconstructive measures are necessary to restore jaw
function and esthetics.
3. Provide adequate results when it includes the overlying
attached oral mucosa.

46. Follow Up
• The literature suggests that most recurrences will present the
first 5 years after primary treatment.
• The recommended follow-up for OKCs is once a year the first
5 years postoperatively.
• Because recurrences or newly developed OKCs may also
present late, a follow-up once every 2 years thereafter seems
a reasonable policy.

47. Prognosis
• Other than the tendency for recurrences, the overall
prognosis is good.
• In extremely rare instances, extend up into the skull base
region.
• A few examples of carcinoma arising in it have been reported,
but the propensity for an odontogenic keratocyst to undergo
malignant alteration is no greater and is possibly less than
that for other types of odontogenic cysts.
• Should be evaluated for manifestations of the nevoid basal
cell carcinoma syndrome particularly if the patient is in the
first or second decade of life.