1. Odontogenic cysts and tumors

2. น่ารู้ Gorlin’s syndrome and OKC : basal cell nevus syndrome
Solid ameloblastoma without cortical bone perforation : excision with bony margin 1 cm
Radiographic feature of benign odontogenic cyst and tumor
Multiple osteoma maybe Gardner syndrome
: familial adenomatous polyposis (FAP) with the extracolonic manifestations of intestinal polyposis, desmoids, osteomas, and epidermoid cysts (ie, Gardner syndrome).

3. Odontogeneis Primitive oral cavity : stomodeum Tooth bud 3 parts
develop from breakthrough of buccopharyngeal membrane , lined with ectoderm
: ectomesenchyme = tissue of tooth develop
Tooth bud 3 parts
Enamel organ : tooth enamel
Dental papilla : tooth pulp + dentin
Dental sac : cementum + periodontal ligament

4. Odontogenesis * Bud,Cap,Bell,Crown Tooth development : 4 stages
Dental lamina stage
Bud stage
Cap stage
Bell stage
* Bud,Cap,Bell,Crown
Interruptions in this sequence may lead to the formation of odontogenic tumors.

5. Dental lamina stage About 6 weeks old
Ridge of basal cell along oral ectoderm
proliferation
Form band of epithelium : dental lamina
( future = dental arch )

6. appearance of a tooth bud without a clear arrangement of cells
Bud stage
Epithelial downgrowth and proliferation
invagination into ectomesenchyme
Represent the beginning of tooth development
appearance of a tooth bud without a clear arrangement of cells

7. A: Epithelial downgrowth along the dental lamina in the upper and lower jaws.
B: A magnified view of the bud stage of development.

8. Cap stage
The first signs of an arrangement of cells in the tooth bud occur
The peripheral cells are cuboidal  the outer enamel epithelium (OEE)
The cells in the concavity are tall columnar cells  inner dental epithelium.

9. Bell stage
The histodifferentiation and morphodifferentiation takes place
A = enamel
B = dental papilla
C = dental follicle

10. Crown stage Maturation stage Hard tissue formation Forming Enamel
Dentin
Cementum
Forming
Odontoblast
ameloblast

12. Definition : Odontogenic
Derived from tooth forming structure

13. Formation of odontogenic cyst and tumor
Derived from :
(1) the reduced enamel epithelium of the tooth crown
(2) epithelial rests of Malassez, which are remnants of the Hertwig root sheath
(3) epithelial rests of Serres, which are remnants of the dental lamina
(4) the tooth germ itself, which includes the enamel organ, dental papilla, and dental sac

14. Diagnosis Complete history
pain, loose teeth, recent occlusal problems, delayed tooth eruption, swellings, dysthesias or intraoral bleeding
onset and course of the growth rate of a mass
parasthesias, trismus, and significant malocclusion
Don’t forget : many of these lesions are associated with
impacted or congenitally missing teeth

15. physical examination
careful inspection, palpation, percussion and auscultation of the affected part of the jaw and overlying dentition
buccal expansion resulting from growth of an odontogenic tumor in the body of the mandible (arrows).

16. A panorex radiograph will often confirm clinical suspicions
well-demarcated lesions outlined by sclerotic borders suggest benign growth
ill-defined lytic lesions with possible root resorption : malignancy

17. DDX By radiographic presentation ( จาก clinical มักไม่แตกต่างกัน )
Radiolucent lesions
Radiopaque lesions
Mixed radiopaque/radiolucent

18. B. Lesions in the midline of the maxilla 1. Median palatine cyst 2
B.    Lesions in the midline of the maxilla   1.    Median palatine cyst   2.    Nasopalatine duct cyst (incisive canal)   C.    Lesion around the crown of an impacted tooth
  1.    Follicular cyst   2.    Ameloblastoma   3.    Ameloblastic fibroma   4.    Odontogenic adenomatoid tumor   5.    Odontogenic myxoma   6.    Odontogenic keratocyst
I.    Radiolucent lesion of the jaws
 A.    Lesions at the apex of the tooth   1.    Dental granuloma   2.    Periapical cyst (inflammatory)   3.    Residual cyst   4.    Periapical (dental) abscess   5.    Cementoma (first stage)   6.    Odontogenic keratocyst

19. E.   
D.    Soap-bubble-like radiolucencies   1.    Multilocular cyst   2.    Aneurysmal bone cyst   3.    Ameloblastoma   4.    Odontogenic myxoma   5.    Central giant-cell granuloma   6.    Odontogenic keratocyst
F.    Miscellaneous radiolucent lesions   1.    Lateral periodontal cyst   2.    Idiopathic bone marrow cavity   3.    Hematopoietic marrow   4.    Gingival cyst   5.    Hemangioma (central)   6.    Osteoporosis   7.    Stafne's bone cavity
E.    Lesions that destroy the cortical plate   1.    Metastatic tumor   2.    Primary malignant tumor   3.    Osteomyelitis

20. II. Radiopaque lesions of the jaws 1. Cementoma (third stage) 2
II.  Radiopaque lesions of the jaws   1.    Cementoma (third stage)   2.    Compound or complex odontoma   3.    Ossifying fibroma   4.    Osteoma   5.    Torus   6.    Root fragment or foreign body   7.    Focal sclerosing osteomyelitis   8.    Osteogenic sarcoma   9.    Chondrosarcoma   10.  Metastatic tumor   11.  Paget's disease

21. III. Mixed radiolucent/radiopaque lesions of the jaws 1
III.  Mixed radiolucent/radiopaque lesions of the jaws   1.    Cementoma (second stage)   2.    Cystic odontoma   3.    Ossifying fibroma   4.    Adenomatoid odontogenic tumor   5.    Calcifying epithelial odontogenic tumor (Pindborg)   6.    Calcifying odontogenic cyst (Gorlin)   7.    Ameloblastic fibroodontoma   8.    Ameloblastic odontoma   9.    Osteogenic sarcoma   10.  Chondrosarcoma

23. Aspiration Biopsy
straw-colored fluid : most likely to be a cystic lesion
pus : an inflammatory or infectious process
White keratin-containing fluid : odontogenic keratocyst
Air may indicate a traumatic bone cavity
Blood represent several lesions : the most important is vascular malformation
inability to aspirate (vacuum within the syringe) is usually indicative of a solid process such as a neoplasm.

24. Indications for excisional biopsy
small
radiographically benign lesions
accessible and can be removed without encroachment on adjacent structures.

25. Odontogenic cysts Inflammatory Developmental
Radicular (periapical) Cyst
Paradental Cyst
Developmental
Dentigerous (follicular) Cyst
Developmental Lateral Periodontal Cyst
Odontogenic Keratocyst (OKC
Glandular Odontogenic Cyst (GOC
True cyst : epithelium lining a collagenous cyst wall

26. Histologically
a fibrous connective tissue stroma with multiple cavernous and sinusoidal spaces with multinucleated giant cells within the stroma
Enucleation is the treatment of choice

27. CLASSIFICATION OF JAW CYSTS
A.    Developmental
  1.    Odontongenic   a.    Follicular cyst   b.    Odontogenic keratocyst   c.    Eruption cyst   d.    Alveolar cyst of infants   e.    Gingival cyst of adults   f.     Developmental lateral periodontal cyst
  2.    Nonodontogenic   a.    Nasopalatine duct cust   b.    Midpalatal cyst of infants   c.    Nasolabial cyst   d.    Globulomaxillary cyst, median mandibular cyst, and median alveolar cyst *

28. B. Inflammatory a. Radicular cyst 1. Periapical cyst 2
B.    Inflammatory   a.    Radicular cyst   1.    Periapical cyst   2.    Inflammatory lateral periodontal cyst
 C.    Nonepithelial   a.    Idiopathic bone cavity (traumatic, solitary, hemorrhagic bone cyst)   b.    Aneurysmal bone cyst   c.    Stafne's mandibular lingual cortical defect

29. CLASSIFICATION OF ODONTOGENIC TUMORS
A.    Benign epithelial odontogenic tumors   1.    Tumors producing minimal inductive change in the connective tissue   a.    Ameloblastoma   b.    Calcifying epithelial odontogenic tumor (Pindborg tumor)   c.    Odontogenic adenomatoid tumor (adenoameloblastoma, adenomatoidodontogenic tumor)   d.    Calcifying odontogenic cyst (Gorlin's cyst)   2.    Tumors producing extensive inductive change in the connective tissue   a.    Ameloblastic fibroma   b.    Ameloblastic fibroodontoma   c.    Ameloblastic odontoma (odontoameloblastoma)   d.    Odontoma   1.    Compound-composite odontoma   2.    Complex odontoma

30. B. Mesenchymal odontogenic tumors 1. Odontogenic fibroma 2
B.    Mesenchymal odontogenic tumors   1.    Odontogenic fibroma   2.    Odontogenic myxoma   3.    Cementoma    a.    Periapical cemental dysplasia   b.    Cementifying fibroma    c.    Benign cementoblastoma   4.    Dentinoma

31. C. Tumors of unknown origin 1
C.    Tumors of unknown origin   1.    Melanotic neuroectodermal tumor of infancy
D.    Malignant odontogenic tumors   1.    Primary intraosseous carcinoma   2.    Ameloblastic fibrosarcoma   3.    Ameloblastic dentinosarcoma   4.    Ameloblastic odontosarcoma

32. Dentigerous (follicular) Cyst
Definition: assosiated with crown of unerupted tooth
accumulation of fluid between reduced enamel epithelium and a completed tooth crown
most common developmental cyst (24%)

33. Dentigerous (follicular) Cyst
Teenage, early childhood
mandibular 3rd molars, maxillary canines, and maxillary third molars
asymptomatic , impacted tooth , bony expansion
Treatment :
enucleation
decompression followed by enucleation if large.

34. Radiographic Features
Unilocular radiolucency
well defined sclerotic margins encircling the crown of an unerrupted tooth
Mandibular cyst can displace into ramus/inferior border of mandible
Maxillary cyst can displace tooth into maxillary sinus

35. Radiographic Features

37. Histologically:
a cyst composed of thin connective tissue walls lined by stratified non-keratinizing squamous epithelium over a fibrocollagenous cyst wall

38. Neoplastic potential Turn to true neoplasm
SCCA
Mucoepidermoid CA
17% of Ameloblastoma from dentigerous cyst

39. Odontogenic keratocyst (OKC)
Parakeratinizing Odontogenic Keratocyst
Keratocystic Odontogenic Tumor (WHO)
WHO  classify as tumor
Soft tissue extension, extension to adjacent bone, bony destruction
Thought to develop from remnants of dental lamina(rests of Seres) , may no tooth associated

40. Odontogenic keratocyst (OKC)
Clinical :
any age, peak incidence 2nd- 3rd decades
75% at mandible
mostly 3rd molar and ramus
Symptomatic  Swelling, pain, trismus, sensory deficit, infection (most common)

41. Odontogenic keratocyst (OKC)
Diagnosis : histologic
High recurrence rate :
Only enucleation : 62.5%
Enucleation + careful curettage: < 10%

42. Why high recurrence ? **Daughter/ Satellate cyst formation**
Collagenase activity of the cyst
Remnant of dental lamina rest at the cyst wall
PG- induced bone resorption
Increase mitotic activity
** OKC need aggressive treatment **

43. Radiographic Features
unilocular/ multilocular
radiolucency
well circumscribed with sclerotic border
teeth may displaced
may seen cortical perforation

44. Radiographic Features
CT scan
Assess large lesion
Assess maxillary lesion
Gorlin syndrome  metachronous, synchronous cyst

45. Histologic : specific criteria Thin,stratified squamous epithelium
Prominent columnar or cuboidal basal cell layer with dense nuclear staining with palisading
“tombstone appearance”
Corrugated surface
Parakeratinizing stratified squamous epithelium
Not pathognomonic
Luminal material : straw-colored clear to creamy white keratin –filled material

46. Treatment Careful enucleation + partial bone removal
Curretage
Peripheral ostectomy with rotary blur
Excision
Bone penetration  remove periosteum
Remove cyst lining, satellite cyst, dental lamina rest

47. Treatment > 1 cyst  Family history (Gorlin syndrome)
Recurrent: within 5 years
Close radiographic F/U
Early detection
Decrease complication of recurrent
> 1 cyst  Family history (Gorlin syndrome)
Carnoy’s solution
Controversial
Chemical cauterization

48. Basal cell nevus syndrome (Gorlin syndrome)
Autosomal dominant
Large variation in expression
Mutation of PTCH tumor supp gene
Multiple OKC of jaw
multiple basal cell CA
Frontal bossing, mandibular prognathism
Palmar,plantar pitting, bifid ribs
Calcification of falx cerebri

49. Basal cell nevus syndrome (Gorlin syndrome)
Recurrence  new occurrence
Large lesion  decompression
Teeth should be saved
Canine, incisor, 1st molar

50. Radicular cyst Periapical cyst, periradicular cyst Clinical
the most common odontogenic cyst (65%)
Arise from the epithelial cell rests of Malassez in response to inflammation
Clinical
Asymptomatic
Associated with Nonvital tooth

51. Radiographic findings
a pulpless, nonvital tooth that has a small well-defined periapical radiolucency at its apex
Microscopically
cyst with a connective tissue wall that may vary in thickness, a stratified squamous epithelium lining, and foci of chronic inflammatory cells within the lumen
Treatment is extraction of the affected tooth and its periapical soft tissue or root canal if the tooth can be preserved.

52. (1,2)Periapical cyst in 60-year-old woman
(1,2)Periapical cyst in 60-year-old woman. CT scan demonstrate radiolucent lesion (arrows) surrounding the apex of molar. defect with den-
filling (arrowhead) is present within the crown of the tooth.
(3) Periapical cyst in 40-year-old man. Panorex im-
demonstrates circular radiolucent lesion (arrow) at the apex of molar. Note the dental filling (arrowhead)

53. Odontogenic tumor

54. Ameloblastoma
Unicystic
Interosseous
Peripheral

55. Ameloblastoma Interosseous type
Solid, not peripheral
Arised from lining odontogenic cyst, reduced enamel epithelium, odotogenic rest

56. Ameloblastoma Interosseous type
80% mandible
Maxilla  may involve sinonasal region
Location of tumor are important for long term prognosis
Anterior maxilla/ body of mandible   
Posterior ramus of mandible   

57. Ameloblastoma Interosseous type
Radiographic findings
Small unilocular radiolucency, well dermacrate
Large  “Soap bubble”, honeycomb appearance
May resorp root in long-standing lesion
Desmoplastic type
Mixed radiolucent radiopaque lesion
Maxilla and anterior portion of jaws

58. Histopathology : 6 patterns
Follicular
Plexiform
Basal cell
Acanthomatous
Granular cell
Desmoplastic
The two most frequent patterns are the follicular and plexiform
Histologic subtypes are not of therapeutic and prognosis important

59. Vickers & Gorlin criteria
Columinar basilar cells
Palisading of basillar cells
Polarization of basillar cells
Hyperchromatism of basal cell nuclei in the epithelial lining
Subnuclear vacuolization of cytoplsam in basillar cells

60. (c) High-power photomicrograph
hematoxylin-eosin [H-E] stain) reveals numerous well-defined islands of odontogenic epithelium with palisading and polarizing nuclei (arrows)

61. Natural history
Ability to infiltrate medullary bone and relative inability to infiltrate compact bone
Dense compact bone
Inferior border of mandible, ramus
Outer periosteum is barrier
The location of tumor
Posterior maxilla, involve orbit

62. Treatment High recurrance Mandibular ameloblastoma
Tumor infiltrate trabeculae of cancellous bone
Mandibular ameloblastoma
1cm of medullary margin
Proximal &distal
Lingual & buccal cortical bone sacrificed
Not include soft tissue outside periosteum

63. Ameloblastoma Interosseous type
Maxillary Ameloblastoma
Margin is more important
Fossen section for soft tissue margin
Margin 1-2 cm
Spare vision, vital structure
F/U  extremely important

64. Ameloblastoma Unicystic type
Intraluminal
Mural
Intramural

65. Ameloblastoma Unicystic type
Definition
Unilocular
Unicystic
Patho lining of ameloblastoma
Vickers & Gorlin criteria
* not invade connective tissue *
Therapeutic planning & clinical behaviors

66. Ameloblastoma Unicystic type
15% of Ameloblastoma
Posterior mandible
Asymtomatic
Radiographic feature
Radiolucent, unilocular
Well dermacrate

67. Treatment Enucleation
Histo  Vickers & Gorlin criteria for Dx Ameloblastoma
Histo: characteristic of luminal or intaluminal involvement
Radiograph singular unilocular radiolucency
No septate
Intra-op confirm of unilocular
No multilocular, multicystic, cortical perforation, soft tissue involvement
Size < 2 cm

68. Peripheral Ameloblastoma
Mucosal mass from gingiva/ alveolar mucosa
From dental lamina rests/ basal cells of mucosa
** Not infiltrate underlying bone**
Bone involvement  intaosseous ameloblastoma

69. Peripheral Ameloblastoma
Diagnosis
CT / MRI
Excision, patho comfirm margin

70. Malignant ameloblastoma
Classic benign histopatho feature
Metastasis to distant location
Lung ( most common)
Cervical LN
Treatment
Depend on degree and site of involvement
Excision
RT (option)

71. Radiographics a unilocular or multilocular radiolucency
with ill-defined borders,
(making it difficult to determine the exact size of the lesion)
Buccal and lingual cortical expansion is common, even progressing to cortical perforation
Root resorption occurs infrequently.

72. “ an infiltrative growth pattern into surrounding tissues ”
Histopathology
The ameloblastoma is unencapsulated,
so it typically exhibits
“ an infiltrative growth pattern into surrounding tissues ”
The basal cells in the epithelium are columnar and hyperchromatic and demonstrate reverse polarity,
( in which the nuclei move from the basement membrane pole of the cell to the opposite pole)
The two most frequent patterns are the follicular and plexiform

73. Odontoma 50% associated with an im- most common
odontogenic tumor of the mandible
approximately 67% of all cases
consists of various tooth components, including dentin and enamel
50% associated with an im-
pacted tooth
Forming between the roots of teeth, the tumor
is initially radiolucent but evolves to contain small
calcifications.orms radioopaque mass with alucent rim

74. Malignant Odontogenic Tumors
Primary Intraosseous Carcinoma
extremely rare tumor
may be of three different types :
  1.    Arising from an odontogenic cyst   2.    Developing from an ameloblastoma   Well differentiated (malignant ameloblastoma)   Poorly differentiated (ameloblastic carcinoma)   3.    Arising from odontogenic epithelium

75. SURGICAL MANAGEMENT OF ODONTOGENIC CYSTS AND TUMORS
goals of management of benign odontogenic cysts
and tumors :
remove all abnormal tissue
conserve healthy bone and dental structures
preserve adjacent structures such as the inferior alveolar nerve
restore the surgical defect to its presurgical state of anatomic form and function
prevent recurrence of the lesion.

76. Enucleation of a lesion
: involves local removal of the lesion by instrumentation
in direct contact with the lesion
Resection
: involves incision or osteotomy through uninvolved
tissue adjacent to the lesion without disruption
of the lesion
Composite resection
: involves removal of tumor, adjacent bone, soft tissue,
and contiguous lymph node channels

77. Enucleation and curettage
  Odontogenic cysts:    Virtually all unless recurrent   
Odontogenic tumors:    Odontoma    Ameloblastic fibroma    Ameloblastic fibroodontoma    Adenomatoid odontogenic tumor    Calcifying odontogenic cyst    Cementoblastoma    Central cementifying fibroma    Unicystic ameloblastoma (except mural type)

78. Marginal or partial resection
 Odontogenic cysts:   Recurrent odontogenic keratocyst  
 Odontogenic tumors:   Ameloblastoma (solid and mural type unicystic)   Calcifying epithelial odontogenic tumor (Pindborg tumor)   Odontogenic myxoma   Ameloblastic odontoma   Squamous odontogenic tumor

79. Composite resection *   
Odontogenic tumors:    Malignant ameloblastoma    Ameloblastic fibrosarcoma    Ameloblastic odontosarcoma    Primary intraosseous carcinoma
These lesions are malignancies and may be treated variably and with additional modalities such as radiation or chemotherapy.

80. management of odontogenic lesion of mandible