The frequency and distribution of periapical cysts and granulomas. An evaluation of 800 specimens.

D entists are repeatedly confronted with the problem of diagnosing and treating periapical lesions. Ordinarily, a nonsurgical cndodontic approach is used in treating lesions that are thnnght to be periapicul granulomas, whereas surgical therapy often is used if the lesion is believed to bc cyst,ic. Thus, choice of treatment usually depends on the clinical assessment of the lesion. Accurate diflercntial diagnosis between radicular cysts and periapical granulomas cannot be made from radiographs a1onc.1-6 Nistologic prevalence studies, therefore, assume special importance and may aid the clinician in making ,judgmcnt,s regarding therapy. Unfortunately, however, different investigators,lSY applying histologic criteria to periapical specimens, have reported very different findings ; the incidence of radicular cysts has ranged from 6 to 55 per cent, and of periapical granulomas from 46 t,o 84 per cent. These wicle discrepancies in data, instead of providing a sound basis for therapy, have added to the clinician’s insecurities. The purpose of this study is to attempt to dispel some of the confusion ('iiUSt!d by conflicting clata front t~wrlicr inrcstigations by ;,rcsrliting aclditiona! information on the frequency ant! distribution of various types of periapical lesion. It is hoped that these data may proviclc a foundation for more rational therapy, particularly with regard to the choice of surgical or nonsurgical cndodontic techniques in the trentmcnt of prriapical lesions.