PATTERNS OF ATTACHMENT LOSS IN ADVANCED PERIODONTITIS PATIENTS MONITORED FOLLOWING INITIAL PERIODONTAL TREATMENT

2 main concepts seem to exist for the progression of periodontitis: (1 ) a slow continuous process of attachment loss; (2) periodic bursts of activity followed by quiescence or remission. This study addresses th is problem and presents data for 69 sites having experienced a net los s of probing attachment amounting to greater than or equal to 3.0 mm o ver 42 months. The sites originated from 16 adult patients monitored a fter nonsurgical treatment of advanced chronic periodontitis. Probing attachment level recordings were obtained every 3rd month. The sequent ial probing attachment level data for each site were smoothed using cu bic splines. Subjective evaluation of the raw and the smoothed data fr om the study sites suggested that the majority of the sites seemed to lose probing attachment in a continuous fashion, and over periods of 1 2 months or more. The smoothed curves were subjected to principal comp onents analysis, which allowed the 69 sites to be ordered according to curve similarity. Nonparametric runs test failed to show that the sha pe of the curves for the sites was significantly associated with any o f the following characteristics: patient, tooth type, tooth surface, i nitial probing depth, bleeding frequency, occurrence of suppuration, o r a combination of inflammatory characteristics of sites.