HARD TISSUE LESIONS

1. HARD TISSUE LESIONS DrNorzalinaGhazali BDentSc, BA (Ire), MClinDent (Child Dental Health) (Mal) Lecturer Faculty of Dentistry UniversitiSains Islam Malaysia (USIM) 20/12/2013

2. HARD TISSUE OF THE BODY • Bone, cementum, dentin and enamel • Bone, cementum and dentin – similar in their composition & formation • They are specialized connective tissues and collagen (principally Type I)

3. HARD TISSUE LESIONS • Most diseases arising in the jaws are of odontogenic origin, but both non-odontogenic and systemic disorders may affect the jaws Can be:- • Developmental • Inflammatory • Infection • Tumours/ malignancies • Genetic • Metabolic

4. CYSTS OF THE JAWS • Cysts – is a pathological cavity having fluid or semi-fluid contents which has not been created by the accumulation of pus, and the majority are lined wholly or in part by epithelium • Symptoms: • Swelling, displacement or loosening of teeth, pain (if infected) • Expansion of bone – may result in an ‘eggshell cracking’

5. Classification (WHO 1992)

6. WHO Classification of Tumours (2005) • OKC is currently designated as a keratocysticodontogenictumor (KCOT) and is defined as a benign uni-or multicystic, intraosseoustumor of odontogenic origin, with a characteristic lining of parakeratinized stratified squamous epithelium with the potential for aggressive, infiltrative behavior • Although they are benign, KCOTs are locally aggressive and have a tendency to recur after treatment; reported recurrence rates range from 3% to 60%

7. Gorlin-goltz syndrome

8. Cysts in children In children: • The most common cysts were DC (44%), followed by EC (21%), TBC (18%), and RC (17%) • The mean ages were 11, 4.3, 14, and 8 years for DC, EC, TBC, and RC, respectively In adult: • The most common cysts were RC (63%), followed by DC (18%), OKCT (10%), and non-odontogenic cyst (9%) • The mean age groups were 42, 50, and 46 years for RC, DC, and OKCT, respectively Manor E. et al., IntJ Med Sci 2012; 9(1):20-26

9. Radiographic findings • Margins – well-defined with peripheral cortication (radio-opaque margin) • Shape – round/ ovoid radiolucencies because most cysts grow by hydrostatic mechanisms • Locularity – unilocular or multilocular appearance because of ridges in the bony wall • Effects on adjacent structures – displacements of a tooth or the inferior dental canal, roots resorption (rare), bony expansion • Effect on unerupted teeth – may become enveloped by any cyst

10. ODONTOGENIC TUMOURS • Are lesions derived from the epithelial and/ or mesenchymal remnants of the tooth-forming apparatus • Asymptomatic, may cause jaw expansion, movement of teeth, root resorption, and bone loss Biologic classification Benign – no recurrence potential • Adenomatoidodontogenictumour, squamous odontogenictumour, cementoblastoma, periapicalcemento-osseous dysplasia, odontoma

11. Benign – some recurrence potential • Cystic ameloblastoma, calcifying epithelial odontogenictumour, central odontogenic fibroma Benign aggressive • Ameloblastoma, odontogenicmyxoma, odontogenic ghost cell tumour Malignant • Malignant ameloblastoma, ameloblastic carcinoma, primary intra-osseous carcinoma, ameloblasticfibrosarcoma

12. Odontoma • Are mixed odontogenictumours – composed of both epithelial and mesenchymal dental hard tissues • Compound – appear as separate, small, tooth-like structures, probably produced by localised, multiple budding-off from the dental lamina, found in anterior region, painless swelling • Complex – appear as amorphous accumulations/ masses of hard tissue (cauliflower-like mass), common in posterior regions Clinical signs: • Retained deciduous tooth, an impacted tooth, alveolar swelling, generally no symptoms

13. Radiographically: • Compound – appear as numerous tiny teeth in a single focus, typically in a tooth-bearing area • Complex – appear as amorphous opaque masses Treatment: • Enucleation • No potential of recurrence

14. Ameloblastoma • Is defined as a benign, locally invasive epithelial odontogenic neoplasm of putative enamel organ origin WHO, 2005 • Is a lesion of adults, rare in children • In children – usually cystic and appear as odontogenic cysts • Most common – mandibular molar-ramus area Biologic subtypes: • Solid ameloblastoma • Unicysticameloblastoma • Peripheral ameloblastoma • Malignant ameloblastoma • Ameloblatic carcinoma

15. Clinical signs: • As a slow-growing, painless swelling, and causing expansion of the cortical bone, perforation of the lingual and/or buccal plates and infiltration of soft tissue • There is often delay in the diagnosis because of its slow-growing nature Radiographically: • A multilocularradiolucency was the most frequently encountered. It also presented with root resorption and was associated with uneruptedteeth • May be unilocular • Well-defined and sclerotic margins due to slow growing

16. Treatment: • Is primarily surgical – range from enucleation, enucleation followed by application of Carnoy’s solution, marsupialization followed by surgery, and resection • There was lack of consensus over the most appropriate treatment for ameloblastomas especially in children • A recurrence rate of 80% for unicysticameloblastoma treated conservatively Ghandhi et al. (2006) • Enucleationof unicysticameloblastoma resulted in the highest recurrence rate; and the lowest recurrence rate was associated with resection of the tumour Lau and Samman (2006)

17. The conservative management is usually performed due to the benign nature of the ameloblastomas despite reported recurrence rates • Several factors are taken in to consideration in the treatment of ameloblastoma in children; these include size, location, duration, mural component, psychological impact, control of possible recurrence and scope for follow-up • A conservative surgical enucleation of unicysticameloblastoma with careful follow-up rather than partial or complete jaw resection appears to constitute appropriate therapy • This is to prevent any interruption in growth and development

20. NON-ODONTOGENIC TUMOURS Primary – benign • Osteoma • Osteochondroma • Cemento-ossifying fibroma • Central giant cell granuloma • Hemangioma Primary – malignant • Osteosarcoma • Chondrosarcoma • Langerhans’ cell histiocytosis Metaststic • Carcinoma Rare in children

21. Giant cell granuloma • Commonly seen in young people • Mandible, anterior to the 1st molars • Frequently only a painless swelling, produce a purplish soft tissue swelling • Radiographically: rounded cyst-like radiolucent area, often loculated or with a soap-bubble appearance, teeth displacement or occasionally root resorption

22. Hemangioma of bone • Rare tumours of bone, commonly in the mandible • Clinically, cause progressive painless swelling which when the overlying bone is resorbed may become pulsatile • Teeth may be loosened • Bleeding from the gingival margins involved by the tumour • Radiographically, there is a rounded or pseudoloculated radiolucent area with ill-defined margind or a soap-bubble apperance

24. Osteosarcoma • Highly malignant, the most common primary neoplasm of bone but overall is rare especially in the jaws • Body of the mandible is a common site, as firm swelling which grows noticeably in a few months and becomes painful • Teeth may be loosened, may be paraesthesia or loss of sensation in the mental nerve area • Radiographically, irregular bone destruction noted

25. Langerhans’ cell histiocytosis • Is a disorder characterized by a proliferation of cells exhibiting phenotypic characteristics of Langerhans cells • 3 forms are recognised: • Eosinophilic granuloma (chronic localized): Solitary or multiple bone lesions • Hand-Schuller-Christian (chronic disseminated): Bone lesions, exophthalmos, diabetes insipidus • Letterer-Siwe (acute disseminated): Bone, skin, internal organs affected

26. Skull, mandible, ribs, vertebrae, and long bones are often involved • Oral changes – initial presentation • Tenderness, pain & swelling, loosening of teeth, gingival tissues are often inflamed, hyperplastic & ulcerated • Radiographically, exhibit solitary or multiple radiolucent lesions which often affect the alveolar bone causing the teeth to appear as if they were floating in space