The relationship between first presentation and subsequent observations in heavy calculus formers

There are few studies that provide information on the natural history of calculus formation. The purpose of this study is to evaluate the relationship between pre-scaling baseline calculus scores, the time since the last prophylaxis before baseline, and scores 8 weeks after scaling in a group of presumed heavy calculus formers. Scaling and polishing were completed on 203 subjects with Volpe-Manhold Index (VMI) calculus scores of 7 or higher, and the date of the last prophylaxis was noted. All were re-examined after 3 weeks. The group included 45.8% males and 54.2% females; the mean age was 41.74 (range = 24 to 72). Racial mix was 57.6% African-American, 39.9% white, and 2.5% other. The mean baseline VMI score was 24.07 (SD = 15.38, range = 7-97). The VMI scores were directly related (P = < .001) to the date of the last scaling and were highest in subjects whose last scaling was more than 2 years earlier (33.67) and least in subjects whose last scaling was less than 6 months previous (15.12). At 8 weeks the mean VMI score was 9.96 (SD = 7.30; range = 0-41). The VMI scores at this time were inversely related (P = < .05) to the date of the last scaling before baseline and were lowest in subjects whose last scaling was more than 2 years earlier (9.07) and highest in subjects with the last scaling less than 6 months previous to baseline (13.07).(ABSTRACT TRUNCATED AT 250 WORDS)