Microbiology 9th Edition by Laura Black, Jacquelyn Black

Exercise 36

Which of the following is NOT true about dental plaque?
(a) It is an intermittently formed coating of microbes and organic matter on tooth surfaces that serve as the first step in tooth decay and gum disease.
(b) It begins as positively charged salivary proteins adhere to negatively charged enamel surfaces, forming a pellicle (film) over the tooth surface.
(c) Streptococcus mutans attaches to the pellicle where it hydrolyzes sucrose to fructose and glucose, or polymers of glucose that serve as bridges, holding together cells in plaque.
(d) Plaque consists of up tO₃0 different genera of bacteria and their products, such as polymers of glucose (dex tran), saliva proteins, and minerals.
(e) Plaque that is allowed to accumulate in crevices near the gumline can change into anaerobic pockets full of bacte ria that can irritate the gums or destroy underlying bone.