<<Prev Common Indications Next>> This screen outlines some common indications for oral radiographs. Trauma and Exodontia Radiography is invaluable for diagnosing and planning the treatment of fractured teeth or bones and the surrounding tissues Radiographs can be used to distinguish between complicated crown fractures (with the pulp exposed) and uncomplicated crown fractures (pulp not exposed) For true representation of root fractures, radiographs should be taken with the primary beam parallel to the angle of fracture. This will allow visualisation of the beginning and end of the fracture line Pre extraction radiographs ensure that a procedure can be properly planned and that no developmental abnormalities, resorptive lesions or ankylosis will surprise the operator Post extraction radiographs ensure that all root fragments are removed and that no collateral damage has been caused. "Favourable" fracture of mid body of mandible with fracture running from caudo-dorsal to rostro-ventral     Lateral view of dog with fractured mandible caudal to symphysis including root tip of canine tooth DV view of cat with fractures to right mandible Intra-oral VD view of rostral mandible. Crowns of premolars had been snapped off using sloppy technique when extracting   Periodontal Disease Radiograph of 408 with advanced attachment loss of caudal root. This four walled pocket or "cup lesion" carries a poor prognosis Intra-oral parallel view showing suprabony pocket interproximally between mandibular molar 1 and premolar 4. The caudal root of PM4 also shows internal root resorption Intra-oral DV skull view showing apical lucency affecting the 102 Extra-oral oblique view of mandible showing apical lucency affecting the mesial root of molar 1. This lesion is tracking externally through the cortical bone of ventral mandible   Loss of attachment is crucial in the treatment planning of periodontal disease. Significant features to look for are: Receding bone height relative to the cemento-enamel junction (CEJ) Loss of bone at interproximal space or at furcation Widening of the periodontal space (this is highly significant) Loss of integrity of lamina dura. The lamina dura is a thin white line around the root. It represents dense cortical bone and is not a structure in its own right. A complete lamina dura is suggestive of good periodontal health. The lamina dura is separated from the tooth by the periodontal ligament (PL), which is relatively radiolucent. The jawbone is trabecular in pattern and varies in density, with age and location. A lack of visible space in the area of the PL may indicate ankylosis of the root Apical rarefaction or "halo". Apical rarefaction, halo or lucency is strongly suggestive of endodontic and/or periodontal pathology. These lesions can be combined and are classified as: class 1 (primarily endodontic pathology leading to periodontal pathology) class 2 (primarily periodontal pathology leading to endodontic pathology) class 3 (combined lesion with endodontic and periodontal lesion occurring independently). Defects and Variations in Tooth Density Caries usually affect the molar teeth of dogs. Loss of normal contour and density will only be visible on a radiograph if pathology is advanced. Therefore, assess grossly and radiographically whether the pulp canal is affected by loss of dentine. Look for apical root pathology or other signs of endodontic disease   Class 1 carie (filled) affecting caudal occlusal pit of mandibular molar 1       Feline Odontoclastic Resorptive Lesions. Treatment planning of these lesions must involve radiography   Feline odontoclastic resorptive lesions (Forl's) class 4 affecting mandibular molar 1 and premolar 3       Internal or external root resorption. This is often secondary to periodontal or endodontic disease   Root resorption (external) affecting multiple mandibular premolars in the dog Endodontic Treatment of Teeth Good quality radiographs from more than one angle are required for a true representation of pulp canal length, width and lack of long axis fracture Intra operative and postoperative radiographs are required to demonstrate the file or gutta percha point position within the canal and adequate filling of the apical third Pulpitis will not show on a radiograph but internal root resorption will be seen as an irregular widening of the pulp chamber Apical rarefaction or "halo". Apical rarefaction, halo or lucency is strongly suggestive of endodontic and/or periodontal pathology. These lesions can be combined and are classified as: class 1 (primarily endodontic pathology leading to periodontal pathology) class 2 (primarily periodontal pathology leading to endodontic pathology) class 3 (combined lesion with endodontic and periodontal lesion occurring independently   Lower canine post-operative root canal treatment Upper canine post-op as oblique lateral and lateral bisecting angles Upper canine post-op as oblique lateral and lateral bisecting angles Developmental Defects and Anomalies Rostral mandibles showing both temporary and permanent dentition   Retained root tip of upper canine in the cat Impacted right lower canine tooth   Detection of missing permanent teeth Detection and treatment planning of mixed dentition including retained deciduous teeth Supernumerary teeth - these can cause crowding problems and are often associated with developmental defects of the crown and/or the root Teeth with developmental problems Teeth with impacted or delayed eruption. Swellings, Cysts and Neoplasms Bilateral follicular dentigerous cysts located around unerupted PM1's   Unilateral dentigerous cyst in a sheep mandible   Osteosarcoma in rostral mandible of a sheep   Cysts present as well demarcated and expansive lytic lesions Neoplasms may present as increased or decreased densities. They are often irregular and poorly demarcated, with lysis of bone. Close examination of the periphery of the lesion will help, as this is often the most active zone in a pathological process Craniomandibular osteopathy (CMO) is usually a lesion of the mandibular body, occasionally the base of the cranium or TMJ's, and produces a proliferative periosteal reaction Osteomyelitis will often present with a proliferative reaction at the periphery, with decreased density at the centre of the lesion   Acanthomatous epulis located buccomesial to 304 Metabolic Diseases Diseases that affect calcium metabolism, such as hyperparathyroidism, present as reduced bone density. Teeth are often quoted as "floating" when the condition is advanced.   <<Prev © 2002 eMedia Unit RVC v1.0 Next>>

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