8/12/2019 Cugini Plaque 2indices

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ABSTRACT 3540

M.A. CUGINI1*,M.C.THOMPSON1, P.R.WARREN1, M. HAZELWOOD2, D.GOODMAN2, D. KING2

1Oral-B Laboratories, Boston, MA; 2STATKING Consulting Inc,Fairfield, OH

OBJ ECTIVE

To assess possible correlations using data from a single use brushing study of an established toothbrush.

METHODS

Oral-B CrossAction manual toothbrush was used by 40 subjects in a supervised single use design.Disclosed plaque was scored pre and

post-brushing using both the RMNPI and the TQHPI. Subjects had to qualify with an initial mean RMNPI score of 0.6 or greater, no

minimum score was required for TQHPI.After the initial scoring,the order for each index was randomized,so that each subject was scored

differently, RMNPI followed by TQHPI or vice versa. One examiner performed all clinical measurements. Pearson Correlations were

performed on whole mouth,buccal and lingual plaque scores.

RESULTS

Correlations between whole mouth RMNPI and TQHPI scores overall (pre/post-brushing scores combined) were positive and approached

perfect correlation,R= 0.99952 (Fig.1).This near perfect correlation was also seen in overall pre-brushing scores,R=0.9755 and overall

post-brushing scores R=0.9912. When pre-brushing scores between the two indices were correlated, the minimum qualifying mean

score for RMNPI of 0.6 or greater corresponded to TQHPI of 2.2 or greater, common plaque entry criteria.When whole mouth change from

pre-brushing scores were correlated with pre-brushing scores the strong positive correlation did not hold and no correlation was found

for either index, R= 0.0453 (TQHPI) and 0.239 (RMNPI) indicating that higher pre-brushing scores do not necessarily predict larger

changes from baseline.Similar results were obtained when overall buccal and lingual means scores were assessed,with correlations of

R=0.9846,0.9942 for RMNPI and TQPI respectively.

PLAQUE INDICES

RMNPI: disclosed plaque on each tooth is evaluated as present or absent (1 or 0).The buccal and lingual tooth surfaces are divided into

9 areas.Whole mouth plaque scores include all areas (A-I), marginal areas are represented by sites A-C and approximal areas as sites D

and F. TQHP involves a modification of the sites using Quigley-Hein Plaque Index. Disclosed plaque is scored at the following six sites:

Mesial, distal and mid surfaces on the facial/buccal and lingual aspect of each tooth.At each site, plaque is scored using the following

0-5 point scale:

CONCLUSIONS

Correlations between RMNPI and TQHPI scores overall (pre/post-brushing scores combined) were positive and approached perfect

correlation.

Correlation between pre-brushing scores for the two indices confirmed that the minimum qualifying mean score for RMNPI of 0.6 or

greater corresponded to TQHPI of 2.2 or greater, a common plaque entry criteria.

Whole mouth change from pre-brushing scores was not correlated with pre-brushing scores for either index, indicating that higher

pre-brushing scores do not necessarily predict larger changes from baseline.

P la q u e a s s es s ed w i t h t w o p l a q u e i n d i c e s - p o s s ib l e

c o r r e l a t i o n s

0 = No plaque / debris

1 = Separate flecks of plaque at the cervical margin of the tooth.

2 = A thin continuous band of plaque (up to 1mm) at the cervical margin

of the tooth.

3 = A band of plaque wider than 1mm but covering less than 1/3 of the

crown of the tooth.

4 = Plaque covering at least 1/3 but less than 2/3 of the crown of the tooth.

5 = Plaque covering 2/3 or more of the crown of the tooth

3.4

3.25

3.1

2.95

2.8

2.65

2.5

2.35

2.2

0.58 0.6 0.62 0.64 0.66 0.68 0.7 0.72 0.74

TQHPI

RMNPI

Fig. 1 Correlation Of Whole Mouth Prebrushing Plaque Scores