The Gingival Index, the Plaque Index and the Retention Index Systems

The authors have taken the liberty of presenting this manuscript in two parts. The first is a brief primer on microbial ecology, because, although the importance of microbial ecology in periodontal diseases is widely recognized, most of us do not know precisely what is meant by the term. The second section is a rather extensive overview of current studies of oral microbial ecology based almost entirely on recent in vivo studies.

https://laurieximenez.files.wordpress.com/2011/02/ref-2_socransky-2005_p2000.pdf

Periodontal microbial ecology.

Comparison of surface roughness of oral hard materials to the threshold surface roughness for bacterial plaque retention: a review of the literature

Oral diseases: a global public health challenge

T H E C H L O R O M E T H Y L A N A L O G U E of Victamine C,* a cationic surface-active agent, reduces the formation of dental calculus in humans. 1 2 This chemical prevents crystallization of calcium phosphate in calculus smears in vitro, 3 but the mechanism whereby it inhibits calculus formation in vivo is not known. The following study was conducted to determine whether the chloromethyl analogue of Victamine C reduces the formation of dental plaque considered a precursor of calculus. 4 6

Reduced plaque formation by the chloromethyl analogue of victamine C.

Experimental Gingivitis in Man

After 9–21 days without oral hygiene eleven experimental subjects with previously excellent oral hygiene and healthy gingivae developed heavy accumulations of plaque and generalized mild gingivitis. The individual rate of development of gingivitis was closely correlated with the rate of plaque accumulation. Characteristic bacteriological changes were revealed in the plaque along the gingival margin during this experiment. Initially, i.e. when the teeth were clean and the gingiva healthy, the extremely sparse plaque flora consisted almost exclusively of gram-positive cocci and rods. The first phase of plaque development occurred during the first 2 days without oral hygiene and consisted of a proliferation of the gram-positive cocci and rods and an addition of about 30 per cent gram-negative cocci and rods. During the second phase (after 1–4 days) fusobacteria and filaments appeared and increased until they each made up about seven per cent of the flora. During the third phase (after 4–9 days) the flora was supplemented with spirilla and spirochetes, and at the end of the period without oral hygiene each of these two groups of organisms accounted for about two per cent of the plaque flora. In specific areas the gingival condition was correlated with the composition of the plaque and it was found that mild gingivitis could be diagnosed clinically at approximately the same time as the complex flora was established. However, sub-clinical inflammation started much earlier, probably as a reaction to the first phases of plaque development. When oral hygiene was reinstituted, the plaque in most areas disappeared in 1–2 days and after 7–11 days the Plaque Index for each subject was as low as before the experiment. Correspondingly, after 1–2 days most tooth surfaces only harbored the original sparse flora of gram-positive cocci and rods. The gingival inflammation in an area usually disappeared one day after the plaque had been removed.

Experimental gingivitis in man. II. A longitudinal clinical and bacteriological investigation.

Experimental gingivitis in man. 3. Influence of antibiotics on gingival plaque development.

Experimental gingivitis in man. 4. Vancomycin induced changes in bacterial plaque composition as related to development of gingival inflammation.

During a 22 day period without oral hygiene 11 dental students rinsed their mouths, twice a day, with a 0.2 per cent aqueous solution of chlorhexidine gluconate. The anaerobic bacterial flora of the gingiva was studied and between days 5 and 10 the proportion of gram negative rods increased temporarily and many exhibited a gliding movement of translation. Nineteen strains of gliding bacteria were isolated and compared with regard to their colonial and cellular morphology and biochemical characteristics. On the basis of these criteria the strains of gliding bacteria are provisionally classified as Fusobacterium girans. Throughout the experimental period none of the subjects accumulated plaque or developed gingivitis.

S B Jensen

Papers

Experimental Gingivitis in Man

Experimental gingivitis in man. II. A longitudinal clinical and bacteriological investigation.

Experimental gingivitis in man. 3. Influence of antibiotics on gingival plaque development.

Experimental gingivitis in man. 4. Vancomycin induced changes in bacterial plaque composition as related to development of gingival inflammation.

Anaerobic gliding bacteria isolated from the oral cavity.