Chemical and Mechanical Plaque control

 All the questions have been directly picked from Carranza 11th edition and Lindhe 5th edition

 

 1.      In  healthy subjects the plaque formation begins on the

a.       Interdental surfaces

b.      Facial surface

c.       Lingual surface

d.      Facial surface on maxilla and lingual surface on mandible

 

Ans: A

 

2.      To achieve caries reduction process, the concentration of fluoride in dentrifices should be

a.       0.7-1.2 ppm

b.      10-100 ppm

c.       500-800 ppm

d.      1000-1100 ppm

 

Ans: D

  Hint✅🔑 

·         Patients at high risk for caries, including those with a history of root lesions or who have active lesions, should use higher-concentration fluoride toothpaste or gels, 5000 ppm, daily until the risk for caries is controlled, then maintain with the lower concentration toothpastes and mouthrinses.

 

3.      “Calculus control toothpastes,” also referred to as “tartar control toothpastes,” contain

a.       Diphosphates

b.      Pyrophosphates

c.       Triple phosphates

d.      Zinc phosphates

 

Ans: B

   Hint✅🔑

·         “Calculus control toothpastes,” also referred to as “tartar control toothpastes,” contain pyrophosphates and have been shown to reduce the deposition of new calculus on teeth.

·         Dentifrice with pyrophosphates has been shown to reduce the formation of new supragingival calculus by 30% or more.

·         Pyrophosphate-containing toothpastes do not affect subgingival calculus formation or gingival inflammation.

 

4.      Themost widely recommended tool for removing plaque from proximal tooth surface is

a.       Dental floss

b.      Wooden tips

c.       Plastic tips

d.      Interdentalbrushes

 

Ans: A

 

 

5.      Recommended length of dental floss for flossing technique is

a.       5-10 inch

b.      6-12 inch

c.       12-18 inch

d.      30-45 inch

Ans: C

 

6.      Type II gingival embrasures

a.       embrasures with no gingival recession

b.      adequately cleaned using dental floss

c.       larger spaces with exposed root surfaces

d.      single-tufted brushes clean efficiently

 

ans: C

  Hint✅🔑 

Types of embrasures and choice of interdental cleaning aids

·         Type I , embrasures with no gingival recession are adequately cleaned using dental floss;

·         TypeII, larger spaces with exposed root surfaces require the use of an interproximal brush; and

·         TypeIII, single-tufted brushes clean efficiently in interproximal spaces with no papillae.

 

 

7.      Not an essential oil mouth rinses

a.       Thymol

b.      Eucalyptol

c.       Chlorhexidine

d.      Menthol

 

Ans: C

  Hint✅🔑 

·         Chlorhexidine digluconate oral rinse is a prescription solutions.

·         Essential oil mouthrinses contain thymol, eucalyptol, menthol, and methyl salicylate

 

8.      Not a side effect of chlorhexidine

a.       Brown discoloration of the teeth

b.      Taste perturbation where the salt taste appears to be preferentially affected

c.       Enhanced supragingival calculus formation

d.      Oral cancer

 

Ans: D

  Hint✅🔑 

In oral use as a mouth rinse, chlorhexidine has been reported to have a number of local side effects (Flotra et al. 1971). These side effects are:

·         Brown discoloration of the teeth and some restorative materials and the dorsum of the tongue.

·         Taste perturbation where the salt taste appears to be preferentially affected (Lang et al. 1988) to leave food and drinks with a rather bland taste.

·         Oral mucosal erosion. This appears to be an idiosyncratic reaction

·         Unilateral or bilateral parotid swelling. This is an extremely rare occurrence and an explanation is not available.

·         Enhanced supragingival calculus formation.

 

9.      Supragingival plaque control reduces

a.      Pocket depth

b.      Gingival inflammation

c.       Loss of attachment

d.      All of the above

 

Ans: B

  Hint✅🔑 

·         Pocket depth and loss of attachment are associated with sub gingival plaque.

 

10.  Chlorhexidine digluconate is

a.       Soluble in water

b.      Sparingly soluble in water

c.       Insoluble in water

d.      Partially insoluble in water

 

Ans: A (lindhe page 748)

  Hint✅🔑 

·         Chlorhexidine is available in three forms, the digluconate, acetate, and hydrochloride salts.

·         Digluconate and acetate salts are water soluble but hydrochloride is very sparingly soluble in water.

 

11.  Most oral formulations and products have used the chlorhexidinedigluconate salt, which is manufactured as a

a.      2%  V/V concentrate.

b.      0.2 %  V/V concentrate.

c.       20%  V/V concentrate.

d.      1%  V/V concentrate.

 

Ans: C (lindhe 748)

  Hint✅🔑 

·         0.2% concentration is W/V not v/v.

 

12.  Chlorhexidine is

a.       a strong acid and dicationic at pH levels below 3.5

b.      a strong base and dicationic at pH levels below 3.5

c.       a strong base and dicationic at pH levels above 3.5

d.      a strong acid and dicationic at pH levels above 3.5

 

  Hint✅🔑

ans:C (lindhe 748)

·         The compound is a strong base and dicationic at pH levels above 3.5, with two positive charges on either side of a hexamethylene bridge.

·         Indeed, it is the dicationic nature of chlorhexidine, making it extremely interactive with anions, which is relevant to its efficacy, safety, local side effects, and difficulties with formulation in products.

 

13.  Which of the following is not the mechanisms proposed for chlorhexidine staining

a.       Degradation of the chlorhexidine molecule to release parachloraniline

b.      Catalysis of Maillard reactions

c.       Protein denaturation with metal sulfide formation

d.      Precipitation of cationic dietary chromogens.

 

Ans: D (lindhe page 749)

  Hint✅🔑 

·         Non-enzymatic browning reactions (Maillard reactions) are catalyzed by chlorhexidine.

·         Precipitation of anionic dietary chromogens is also caused by chx.

 

14.   Chlorhexidine is a useful mouthwash as [2072/12/1]

a.       It prevents plaque accumulation.

b.      It prevents bacterial proliferation

c.       It breaks down plaque matrix

d.      It causes haemostasis

 

Ans: A[lindhe page 750]

15.  Not true about chlorhexidine

a.       At low concentration this binds to bacterial cell membrane and results in increased permeability with leakage of intracellular components including potassium.

b.      Plaque inhibition is derived only from the chlorhexidine adsorbed to the tooth surface.

c.       If chlorhexidine does not stain the tooth, it does not work.

d.      The molecule attaches to pellicle by both cation making the attachment stronger.

 

Ans: D [lindhe page 750]

  Hint✅🔑

Chlorhexidine mechanism

·         The antiseptic binds strongly to bacterial cell membranes.

·         At low concentration this results in increased permeability with leakage of intracellular components including potassium. (bacteriostatic)

·         At high concentration, chlorhexidine causes precipitation of bacterial cytoplasm and cell death.

·         In the mouth chlorhexidine readily adsorbs to surfaces including pellicle-coated teeth and shows a substantivity of 12-16 hours

·         Plaque  inhibition is derived only from the chlorhexidine adsorbed to the tooth surface.

·         the molecule attaches to pellicle by one cation leaving the other free to interact with bacteria attempting to colonize the tooth surface.(PIN-CUSHION EFFECT)

 

 

16.  PIN-CUSHION EFFECTis responsible for

a.       Inhibiting bacteria to colonize the tooth surface.

b.      Staining of the tooth by chlorhexidine

c.       Reduction in the plaque inhibition of chlorhexidine by toothpaste if used shortly after rinses with the antiseptic.

d.      All of the above

 

Ans: D [lindhe page 750]

  Hint✅🔑 

·         This mechanism would, therefore, be similar to that associated with tooth staining.

·         It would also explain why anionic substances, such as sodium lauryl sulfate based toothpastes, reduce the plaque inhibition of chlorhexidine if used shortly after rinses with the antiseptic (Barkvoll et al. 1989). Indeed, a more recent study has demonstrated that plaque inhibition by chlorhexidine mouth rinses is reduced if toothpaste is used immediately before or immediately after the rinse (Owens et al. 1997b).

 

 

17.  First modern tooth brush was invented by

a.       Chinese

b.      English

c.       American

d.      Japanese

Ans: B

  Hint✅🔑 

·         First toothbrush was invented in china.

·         But the first tooth brush of modern design was made by William Addis in England around 1780.

 

18.  Chlorhexidine was introduced by

a.      Glickman

b.      Russell

c.       Socransky

d.      Loe

 

Ans: d Loe [lindhe page 738]

  Hint✅🔑

Plaque inhibition by chlorhexidine was first investigated by Schroeder but the definitive study was done by Loe and Schiott.

 

19.  Father of oral hygiene is

a.      Clark

b.      Fauchard

c.       Rhein

d.      Fones

 

Ans: d Fones

 

20.  Disclosing agents stain

a.      food debris

b.      Plaque

c.       Materia alba

d.      Calculus

Correct answer: b. Plaque

  Hint✅🔑 

·         Disclosing solution helps in checking the efficacy of oral prophylaxis for young patients

·         Erythrosine is the most widely used disclosing agent and stains plaque red n colour

·         In 2 tone solution, new plaque stains red whereas old plaque stains blue.

 

21.  Which of the following wax coating is present in dental floss

a.      Bees wax

b.      Spermaceti wax

c.       japan wax

d.      Carnauba wax

 

Ans: b. Spermaceti wax

 

22.  Which brushing technique is used in severe gingival recession and loss of gingival contour

a.      Bass

b.      Stillman

c.       Charter

d.      Fones

 

Ans: b Stillman

 

23.  For periodontal patients, the recommended method of brushing is

a.      Scrub technique

b.      Roll technique

c.       Sulcular

d.      Fones

 

Ans: c Sulcular technique

  Hint✅🔑 

Tooth Brushing techniques

·         Recommended technique for children- Fone’s technique

·         Least effective technique-Roll technique

·         Most common method-Scrub technique

·         In cases of healing wounds after surgery- Charter’s method

·         Severe gingival recession and loss of gingival contour: Stillman

·         Orthodontic patient or FPD: Charters method