Radix paraentomolaris - A rarest of rare structural entity

The mandibular first molars ( primary and permanent) usually have 2 roots located mesially and distally, but occasionally they have an additional root located distolingually requiring special attention when root canal treatment is being considered . The additional root is regarded as a normal racial and morphological variation rather than as an abnormality. It appears to be more common in races of Mongoloid origin, including Malay, Chinese, Japanese, Eskimo, and American and Canadian Indian populations.To study about the rarest root and root canal anatomy using spiral ct and r.v.g. Computed tomography and radio visiography has long been used as a diagnostic aid in dentistry .With the advent of new diagnostic aids like spiral computed tomography it has become very easy for the dentist to diagnose different root and root canal anatomy and accordingly plan the treatment.