DISEASES OF FACIAL JAW BONES

             Diseases of Facial Jaw Bones

             By Najam us Sahar

Facial Jaw Bones comprises of two parts Upper jaw (maxilla), Lower jaw (mandible) .The maxillae are formed by the fusion of two halves of palate at the intermaxillary suture with the maxillary arch. The lower jaw   (mandible) is a U-shaped bone. It is the only mobile bone of the facial skeleton, and, since it houses the lower teeth, its motion is essential for mastication

Sclerosing Lesions of the Jaws

Sclerosis is the hardening or indurations of tissue usually due to increased calcification appear radiopacity .Bone sclerosis may cause due to Paget’s disease and fibrous dysplasia. Sclerosis in localized areas is more common. Limited mouth opening and decreased tongue mobility is the characteristics feature of Sclerosis

Hypercementosis

Hypercementosis is the excessive growth of secondary cementum over the apex and the body of the root, root become bulbous and expanded. The expanded root is still surrounded by lamina dura periodontal membrane space. Removal of such teeth is difficult

Cementoma

Cementoma is a benign tumor of cementum origin. Cementoma are the dense areas of coarse trabeculation found at the apices of teeth. These are fibrous outgrowth in periodontal ligament space. Initially it appears as multiple radiolucencies in radiograph. Lamina dura is destroyed, fibrous tissue becomes calcified

 Postinflimmatory SclerosingOsteitis

It is Benign Osteosclerosis, has no aetiology characterized by Increase in bone density at apical and interdentally region, Periodontal ligament space widened, lamina dura destroyed due to chronic sepsis. Caries and apical resorption also present .This lesion is followed by Surgery, extraction or a bridge. Sclerosis is seen between the teeth and adjacent to root. This lesion is common and benign and should be left alone .

Odontomes

These are dental hamartomas, benign tumor of odontogenic origin (i.e. linked to tooth development) containing enamel, dentine, cement and connective tissue

Complex Odontoma

Tumor consist of lobulated density surrounded by radiolucent zone .These are  Common in molar region .

Compound Odontoma

These are multiple small united denticles in which individual cusps may be recognized  and common in canine region

Paget’s disease(Osteitis deformans)

Peget’s disease is a localized disorder of bone remodeling, result in enlarge and mis shapen bones. It appears as Irregular dense Sclerotic patches may form on teeth. Infection is relatively common, from a recent socket from a dead tooth. There is  Neuralgic pain in an enlarging alveolar ridge also present. Fracture and neoplasm are rare in peget’s disease. 

Trauma

             Teeth can become chipped, cracked, broken into pieces and                            knocked out completely.

              This usually happens as the result of a minor or major accident (trauma)

                            

         Classification of injuries to the teeth

         Class 1: Traumatized tooth without fracture     

                           a) With loosening b) without loosening

            Class 2 Fracture of the crown

                         a) Involving enamel b) involving dentine

            Class 3 Fracture of the crown, exposing pulp

            Class 4 Fracture of the root

                       a)      Without crown fracture b) with crown fracture

          Class 5 Avulsion of the tooth                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   

Dysplasia 

 
 Localized Fibrous                       dysplasia                                                                                                                                       
 It  occurs as enlargement of one side of maxilla. The lesion is homogenous usually in maxilla and dense than the normal bone. It appears with increased radiolucency

  Cherubism

  The mandible is enlarged by radiolucent area of cystic and fibrous change .

   Agenesis of teeth occurs in affected area, teeth become displaced, separated from each other                  and unerupted.

  Cleidocranial dysplasia

The maxilla under developed, the small jaw thus show the large number of crowded  supernumerary,   primary and secondary teeth.

  Ectodermal dysplasia 

 In ectodermal dysplasia ,there is partial or total absence of teeth , andodintia often only central     teeth are present with conical crown