Surgical Management of Oral Pathological Lesions

1. Surgical Management of Oral Pathological Lesions

2. Overview Odontogenic cysts & tumors arise from the odontogenic apparatus. The odontogenic apparatus consists of: Epithelium: Remnants of dental lamina Reduced enamel epithelium Odontogenic rests Lining of odontogenic cysts Basal cell layer of oral mucosa Ectomesenchyme: Dental papilla

3. What is a cyst? Definition: A cyst is a pathological cavity with fluid, semi-fluid or gaseous contents, which is not created by accumulation of pus. It is frequently lined by epithelium. Typical features:a) Cysts grow slowly and expansivelyb) Form sharply-defined radiolucencies with smooth bordersc) Frequently they are found as an incidental radiographic finding.

4. Classification Odontogenic cysts: Inflammatory: Periapical (radicular) cyst Residual periapical (radicular) cyst Developmental: Dentigerous cyst Odontogenic keratocyst (OKC) Gingival (alveolar) cyst of the newborn Gingival cyst of the adult Lateral periodontal cyst Calcifying odontogenic (Gorlin) cyst Eruption cyst Non Odontogenic cysts that are not really cysts: Nasopalatine duct cyst, Nasolabial cyst, Dermoid cyst, Cysts without epithelial lining: Simple bone cyst Aneurysmal bone cyst

5. Diagnostic modalities Panoramic Radiograph, CBCT are most valuable diagnostic tools for detection Histopathology Confirms diagnosis.

6. Clinical Features Noticeable swelling: Initially smooth bony hard swelling with normal overlying mucosa As bone thins through resorption, cyst may show through as bluish fluctuant swelling (may be compressible in nature) Discharge into mouth Pain due to secondary infection Fluid may be aspirated Thin-walled cysts may be trans illuminated

7. Basic Goals Eradication of Pathological condition Functional rehabilitation Broad Classification Cysts Cystlike lesions of the jaws Benign tumors of the jaws Benign tumors of the soft tissues Malignant tumors

8. Cysts Surgical Management Four methods Enucleation Marsupialization A staged combination of two procedures Enucleation with curettage

9. Enucleation Definition : Shelling out of the entire lesion without rupture Indications Any cyst that can be removed without sacrificing any adjacent vital structures. Advantages Cyst is removed entirely Complete Histopathology Disadvantages Devitalization of teeth Jaw fracture w/o curettage OKC may be left behind

11. Marsupialization Definition Decompression Referred to as Partsch procedure Surgical window is created and contents of the cyst are evacuated Continuity b/w cyst and OC, or Maxillary Sinus is maintained

12. Marsupialization - Indications Amount of tissue injury Proximity to vital structures ( OA Fistula, Damage to IAN, devitalization of teeth) Surgical access Difficulty in accessing the areas Assistance in eruption of teeth Unerupted tooth in the arch Extent of surgery Patients Medical status Size Large cyst (Jaw#)

13. Marsupialization • Advantages • Simple • Spares vital structures • Disadvantages • Pathologic tissue left in situ • Recurrence • Post operative maintainence • Longer time to heal

14. Marsupialization - Technique Initial Incision circular, extending into cystic cavity Osseous window-Bur, Rongeurs Removal of window of cyst lining Evacuate contents Irrigation Perimeter of the cystic lining is sutured to oral mucosa/ Pack the cavity with strip of gauze

15. Post operative care Pack-Changed after 10-14 days ( prevents the mucosa from healing over the window) Frequent irrigation Enucleation is performed after marsupialization Residual cavity may not obliterate

16. Enucleation after Marsupialization • Combined approach reduces morbidity • Accelerates healing pocess • Indications: Same as marsupialization • Advantages/Disadvantages • Rationale : • Osseous healing is allowed to practice • Once cyst has reduced in size, enucleation is more amenable

17. Technique • Marsupialization • Wait for cyst to decrease in size • Check if sufficient bone has formed over the vital structure • Enucleation

18. Intravenous tubingfashioned into a drain by heatingand flattening the ends.

21. Enucleation with curettage • 1-2mm of bone is removed around the entire cystic cavity • Indications • OKC ( recurrence is between 20% to 60%) • Recurrence of cyst • Advantages/Disadvantages • Technique

22. Ameloblastoma • Epithelial Origin • Pathogenesis • Originates from epithelium involved in formation of teeth • Trigger for neoplastic transformation of theses epithelial residues are unknown • Clinical Features • Benign aggressive tumor • Invasive and persistent • Age- mean age 40 years • Mandibular ramus area • Radiolucent • Unilocular/multilocular • Slow growing

23. Technique- Marginal or Partial Resection • Indication: • Aggressive lesion (confirmed by histopathology) • Removal by curettage/enucleation difficult • General Rule : • Resected specimen should include LESION + 1 cm of bony margins around radiographic boundaries

24. Overview of treatment • Benign/Malignant • Aggressiveness of the lesion • Anatomic location of lesion • Proximity to adjacent vital structures • Size of the tumor • Intraosseous versus extra osseous location

25. Overview of treatment • Duration of the lesion • Reconstructive efforts • Treatment method • Treated with Curettage, enucleation or both • Treated with Marginal or Partial resection

26. Jaw tumors treated with Enucleation, curettage or both • Indications: • Tumors with low recurrence rate • Technique • Similar to procedure described with cysts • Additional sectioning might be necessary for sectioning large osseous masses

27. Technique- Marginal or Partial Resection • Indication: • Aggressive lesion (confirmed by histopathology) • Removal by curettage/enucleation difficult • General Rule : • Resected specimen should include LESION + 1 cm of bony margins around radiographic boundaries

28. Malignant Tumors of the Oral cavity • Origin • Most common tumor • Treatment • Surgical • Radiotherapy • Chemotherapy • Combination of any one of the above • Factors affecting treatment planning

29. Staging- TNM System • T = the size of the primary Tumor • N = the status of the cervical lymph Nodes • M = the presence or absence cancer in sites other than the primary tumor (Metastasis) • Staging is defined through physical examination, diagnostic tests, and biopsies.

30. What Does Each Stage Mean? • T- Tumor • N-Lymph node involvement • M-Metastasis

31. Codes Describing the Tumor (T) • TX primary tumor cannot be assessed • T0 no evidence of primary tumor • Tis carcinoma in situ • T1 tumor less than 2 centimeters (cm) in greatest dimension • T2 tumor more than 2 cm but not more than 4 cm in greatest dimension • T3 tumor more than 4 cm in greatest dimension • T4 tumor invades adjacent structures (mandible, tongue musculature, maxillary sinus, skin)

32. Codes Describing Nodal Involvement (N) • NX regional lymph nodes cannot be assessed • N0 no regional lymph node metastasis • N1 metastasis in a single ipsilateral lymph node, less than 3 cm in greatest dimension • N2a metastasis in a single ipsilateral lymph node, more than 3 cm but not more than 6 cm in greatest dimension • N2b metastasis in multiple ipsilateral lymph nodes, none more than 6 cm in greatest dimension • N2c metastasis in bilateral or contralateral lymph nodes, none more than 6 cm in greatest dimension • N3 metastasis in a lymph node, more than 6 cm in greatest dimension

33. Codes Describing Metastasis (M) • Mx – Metastasis cannot be assessed • M0 - No distant metastasis • M1 - Distant metastasis

34. Stage Grouping Stage Grouping • Stage I- T1N0M0 • Stage II- T2N0M0 • Stage III-T3N0M0 • T1 or T2 or T3N1M0 • Stage IV-T4N0 or N1M0 • Any T, N2, or N3M0 • Any T, any N, M1

35. Oral Cancer – The Patient’s Journey • Cancer Diagnosis • Pre-treatment Dental Management • During Treatment Management • Post Treatment Dental Management

36. Pre Treatment Dental Management • Restorations / Extractions • Oral Hygiene Programme • Debridement • Diet Advice • Use of Fluoride Trays • Smoking Cessation “Prevention is better than cure”

37. Radiotherapy • Mechanism of Action • Actively growing tumor cells are more susceptible to radiation • Interferes with nuclear material • 3 H s • Types- • Low dose brachytherapy • Needles, cesium, irridium wires • External Radiation sources • Fractionation • Multiple beams (portals)

38. How does radiation kill cells? H H• O• High energy particle (b, g) H O H H H• Free radicals O• O2 HOO• Secondary reactions with DNA (and other macromolecules) Mutations

39. Guidelines for management of a patient for a surgical Procedure Before radiotherapy • All mandibular carious teeth in field of radiation (>6000 cGy)should be extracted • Full bony impaction should be left in place • Optimal time of procedure-3weeks prior to radiation • Radical alveolectomy with primary closure • Less optimally- Extractions can be done within 4 months of completion of therapy

40. Guidelines for management of a patient for a surgical Procedure During radiotherapy • Palliative treatment only • Pulpectomy • Pulpotomy • Incision and drainage • Extractions should be avoided or delayed until after radiotherapy

41. Guidelines for management of a patient for a surgical Procedure After radiotherapy • Careful management to prevent ORN • Recall every 3 month for prophylaxis • Daily flouride application • Restorative dentistry procedure may be performed as needed • If mucositis has cleared prosthetic appliances may be fabricated • Avoid invasive procedures • Within 4 months of completion of radiotherapy minor OS procedures

42. Radiotherapy / Chemotherapy Side Effects • Mucositis • Dry Mouth • Radiation Caries • Osteoradionecrosis

43. Mucositis • 83% of HNC patients develop mucositis • 29% developed severe mucositis • Short term effects • Long term effects Vera – Lionch M, et Al Oral mucositis in patients undergoing radiation treatment for head and neck carcinoma Cancer. 2006 Jan 15;106(2):329-36

44. Management of irradiation Mucositis and Xerostomia • Keep the mouth , teeth moist and plaque free • NO Spicy food, carbonated drinks, commercial mouth washes, peroxide rinses, Alcohol,tobacco use • Encourage sugarless candy and gum chewing • Liquid or semisolid diet • Salivary substitutes- • No dentures to be worn on areas with mucositis • Baking soda if toothpaste irritates

45. Trismus - Limited Opening • 5% - 38% prevalence • Site of Cancer • Surgery • Radiation of TMJ or Medial Pterygoid Muscle • Plast Reconstr Surg. 2006 Jul;118(1):102-7

46. Exercise/ Physiotherapy

47. Dry Mouth • Reduced Flow • Thick / Stringy • Loss of taste • Difficulty swallowing • Speech • Recovery depends on site and dose of Rx

48. Use of Fluoride Fluoride / Chlorhexidine Regime each alternate day for 10-15 minutes in dental trays

49. Osteoradionecrosis • Disease of irradiated bone that may lead to marked pain, bone loss and functional or cosmetic disability • Site: Mandible > Maxilla (Why?) • Radiation in excess of 6000 rad causes death of bone cell and in progressive obliterative arteritis

50. Sequence of Events • Radiation----HHH---- Breakdown of tissue -----Non healing wound • Clinical features • Pain • Evidence of exposed bone (gray/yellowish color) • Trismus • Fetid odor • Usually associated with intra/extra oral fistula