Self Learning, Self Assessment 2010 (September 01, 2010)

Question 33

A thin biotype gingiva often displays recession and poor aesthetics.

For an aesthetic smile the apices of the gingivae of the maxillary central incisors should be at the same level.

A. The first statement is true, the second is false.

B. The first statement is false, the second is true.

C. Both statements are true.

D. Both statements are false.

Rationale

Two biotypes of the gingivae are recognized – thick and flat, and thin and scalloped. The former resists recession whereas thin biotype tends towards poor aesthetics by recession, particularly after any treatment involving the periodontium. For maximum aesthetics gingival tissue should be pink, stippled and the papillae pointed and tight to the cervical margin of the teeth. In terms of height a line between the apices of the gingiva of both central incisors should be at the same level. An extension of this line back to the molars should lie in a continuum. Excessive gingival display beyond this causes a non aesthetic “gummy smile”.

References

1. Leblebicioglu, B., Rawal, S. and Mariotti, A. A review of the functional and esthetic requirements for dental implants. JADA 138 : 321 – 329, 2007.

2. Secrets of cosmetic dentistry (3) Perio aesthetics. Canadian Journal of Cosmetic Dentistry 22 – 24.

Question 34

Cluster headache

1. peaks at 20 – 30 years of age.

2. has major periods of remission.

3. affects the maxillary teeth.

4. is located around the orbit.

A. 1, 2, 3

B. 1 and 3

C. 2 and 4

D. 4 only

E. All of the above.

Rationale

Cluster headache (CH) is characterized by severe, strictly unilateral pain attacks and occurs more frequently in men than women. Its peak age of onset is between 20 and 31 years. The pain is localized deep in and around the orbit and temporal region and may radiate to the maxilla, nostril, upper teeth, gingiva, palate and jaw. It is accompanied by ipsilateral conjunctival injection, lacrimation, nasal congestion, rhinorrhea, forehead and facial sweating, miosis, ptosis and eyelid oedema. The pain lasts on average from 15 minutes to 3 hours, and the headache occurs at least once every other day for a period of weeks or months, followed by a remission of weeks or years.

Reference

Balasubramanian, R. and Klasser, G.P. Trigeminal autonomic cephalalgias. Part1: cluster headache. 0000E 104 : 345 – 354, 2007.

Question 35

Oral malodour is caused by volatile sulfur compounds found in dental plaques.

A dentifrice with triclosan and copolymer gives control of poor breath odour for 12 hours after brushing.

A. The first statement is true, the second is false.

B. The first statement is false, the second is true.

C. Both statements are true.

D. Both statements are false.

Rationale

The pathogenesis of oral malodor is associated with the degradation of sulfur-containing bacteria into volatile sulfur compounds. Some of these bacteria are located in plaque, the gingival sulcus and dorsum of the tongue. A double blind clinical study was undertaken to investigate the effectiveness of a dentifrice containing triclosan and a copolymer for controlling breath odor 12 hours after brushing the teeth compared to a placebo dentifrice which did not contain triclosan or a copolymer. The results of the study showed that after 12 hours a mean breath odor score for the test group was within the range of values for pleasant breath. The control group presented a mean breath odor score above the threshold corresponding to unpleasant breath which was statistically significant. A dentifrice containing triclosan with copolymer provides effective control of breath odor 12 hours after brushing the teeth.

Reference

Sharma, N.C., Galustians, H.J., Qaqish, J. et al. Clinical effectiveness of a dentifrice containing triclosan and a copolymer for controlling breath odor. American Journal of Dentistry. 20: 79 – 81, 2007.

Question 36

Which of the following ions, released by glass ionomers, can promote remineralization?

1. Fluoride.

2. Aluminum.

3. Calcium.

4. Magnesium.

A. 1, 2, 3

B. 1 and 3

C. 2 and 4

D. 4 only

E. All of the above.

Rationale

Glass ionomer has many advantages. Of clinical importance is its hydrophilic nature and its ability to set rapidly. Glass ionomers release fluoride, which allows remineralization of enamel. Fluoride ions are taken up by the enamel, which renders the tooth structure less susceptible to acid challenge. The ability of glass ionomer to release other ions, notably calcium and aluminum, has been studied and there is evidence to show that these ions also promote remineralization.

Reference

Lindemeyer, R.G., The use of glass ionomer sealants on newly erupting permanent molars. JCDA 73 : 131 – 134, 2007.

Answers to the August 2010 SLSA questions:

29. C

30. E

31. E

32. C

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