Evaluation of a Modified Interproximal Technique as a Novel Radiographic View for the Diagnosis and Staging of Periodontal Defects of the Maxillary Fourth Premolar Using an Experimental Model of Induced Bone Loss in Dogs

Diagnosis of canine periodontal disease relies on clinical and radiographic evaluation including the simplified bisecting angle (SBA) technique. However, difficulty in visualizing the alveolar bone margin and misinterpreting its distance from the cemento-enamel junction (CEJ) diminishes its usefulness. The objective of the study was to compare a new radiographic view, the modified interproximal (MIP) technique, to the SBA technique for the detection of bony defects and furcation involvement in a canine experimental model of periodontal disease of the maxillary fourth premolar tooth (PM4). The authors hypothesized that the MIP technique would detect milder bony defects and furcation exposure compared to the SBA technique. Eleven large breed dog cadavers with mesaticephalic or dolichocephalic skull conformation and without periodontal disease were used. Dental radiography with SBA and MIP techniques was acquired prior to and after creating a horizontal pattern of bony defects, centered on PM4 in 12.5% increments, from 0% to 50% bone loss. The level of the bone margin and furcation exposure was evaluated. Inter- and intraobserver agreement was substantial. Observers systematically underestimated the distance between the CEJ and the bone margin with both radiographic techniques. MIP technique performed better overall than SBA technique (accuracy and sensitivity were significantly improved). These results show that MIP technique is more accurate than SBA in the evaluation of mild bony defects and furcation lesions associated with PM4. Adding a MIP view of PM4 to the canine full-mouth survey may improve detection of bone loss and furcation involvement.