A Statistical Analysis of Surgical and Nonsurgical Endodontic Retreatment Cases

By Allen R, Newton C, Brown C.

Date: 10/1990
Journal: JOE

Purpose: quantify the outcome of root canal retreatment and effect of various factors on success.

•N = 1300 patients , al least 6 month RG should be present


•Charts of patients were reviewed: age, sex, tooth #, if it was symptomatic at retreatment, if PA lesion was present, type of filling, perforation, separated instruments:

•Retreatment cases was divided according to time of original treatment: 1.Treated before or on 1970 (silver points)

2.Between 1971-1975 (gutta percha and standard preparation)

3.Between 1976-1980 (tapering preparation, fewer appointment ,heated gutta perch )

•Type of original treatment was recorded

Success: cases with complete regression or no formation of PA lesion, no widening of PDL, intact lamina dura.

Uncertain: cases with reduced PA lesion

Most highlighted Results:

•Distribution of retreatment according to teeth type (table2). 59% had symptoms, 88% had PA lesion.

•Histological examination of surgery cases showed: granuloma (66%), cysts (28%).

•Teeth which were permanently restored after retreatment exhibited significantly more success(69%) than those which were not( 51%). •Retreatment of past fillings had significantly lower success rate %,