2004 Self Learning Self Assessment

The SLSA Program is based on a series of questions, answers, rationales and references followed by an annual 15-question quiz. All material is from current referenced literature. Completion of the quiz leads to CE points. Names and license numbers of dentists are forwarded to the appropriate licensing authorities.

QUESTION 25

The bi-chambered delivery system of dual phase toothpaste

1. isolates the calcium portion from the phosphate.

2. allows the release of calcium, phosphate and fluoride ions into the saliva.

3. improves remineralization through brushing.

4. has no effect on caries incidence.

A. 1, 2, 3

B. 1 and 3

C. 2 and 4

D. 4 only

E. All of the above

Rationale

Tooth enamel is under cariogenic and demineralization attack constantly. The oral environment is capable of removing mineral substance from the teeth, which, if unchecked, will allow cavitation to develop. Remineralization is a natural phenomenon and, under appropriate conditions, deposition of mineral will occur, reversing the carious process. Factors determining the correct direction of remineralization are pH, the concentration of mineral ions and their availability in the saliva, as well as the severity and frequency of the cariogenic challenges.

Amorphous calcium phosphate, because of its solubility, can enhance the calcium and phosphate ions in saliva. The simultaneous application of fluoride ions with high concentrations of calcium and phosphate ions improves remineralization. This has resulted in the development of a dual phase system toothpaste which isolates the calcium portion of the paste from the phosphate and fluoride portions until the time of application, when the ions of all three are released in the saliva to support remineralization.

A study involving 2,506 children examined the use of this bi-chambered dentifrice in the management of dental caries in 5-17 year-olds. One group of children was given the test dentifrice in which one chamber contained 0.243% sodium fluoride in a silica base and the other chamber dicalcium phosphate dihydrate. The other test group received 0.243% sodium fluoride in the silica base only. Using DMFS scoring, the mean caries increments after the first year failed to show significance between the two groups. However, after two years, the figures were statistically significant and represented a 14.38% decrease in the overall caries score.

REFERENCES

1.Boneta, A.E., Neeswith, A., Mankodi, S. et al. The enhanced anticaries efficacy of a sodium fluoride and dicalcium phosphate dihydrate dentifrice in a dual chambered tube: a two-year caries clinical study on children in the United States of America. Am J Dent 14:13A-16A. 2001.

2.Oral Care Report, Vol 9 No.1 Ed. C.W. Douglass, 1999.

QUESTION 26

In the first year of loading, bone loss around Brnemark implants placed in men is greater than around those placed in women.

Brnemark implants show more bone loss in the maxilla than in the mandible in the first year of loading.

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

A recent Canadian study over a twelve-year period examined the bone level changes seen around implants of the Brnemark system. The implants were used to support fixed partial prostheses and clinical bone measurement was determined by radiography.

Implants placed in men showed greater bone loss in the first year of loading. No difference between the sexes was seen for mean annual loss thereafter. Implants in younger subjects lost more bone over the first year of loading than those placed in older subjects. In part, this may be due to the likelihood of placement in alveolar bone rather than basal bone. Comparing jaws, there was more bone loss around implants in the mandible than the maxilla in the first year of loading.

REFERENCES

1.Wyatt, C.C.L., Zarb, G.A. Bone level changes proximal to oral implants supporting fixed partial prostheses. Clin Oral Impl Res 13:162-168. 2002.

2.DeSmet, E., Jacobs, R., Gijbels, F., et al. The accuracy and reliability of radiographic methods for the assessment of marginal bone level around oral implants. Dentomaxillofacial Radiology 31:176-181. 2002.

QUESTION 27

An avulsed central incisor in a 12-year-old has been out of the mouth for 15 hours. Replantation requires

1. removal of the periodontal ligament.

2. soaking the tooth in fluoride solution.

3. filling the root canal extraorally with gutta percha.

4. splinting the tooth rigidly for six weeks.

A. 1, 2, 3

B. 1 and 3

C. 2 and 4

D. 4 only

E. All of the above

Rationale

The majority of replanted teeth demonstrate resorption within 2-5 years. The degree of resorption is closely related to the length of the extraalveolar time period. In instances of very prolonged extraalveolar dry time as in this case, replantation can be attempted. In such cases, the periodontal ligament should first be removed, the tooth soaked in fluoride, the root filled extraorally with gutta percha, the tooth rinsed in saline for two minutes, the blood clot removed gently from the socket and the replanted tooth splinted rigidly for six weeks to allow for ankylosis.

REFERENCE

Titley, K., Farkouh, D. Avulsed teeth-to replant or not to replant? Oral Health, July 27-29, 2002.

QUESTION 28

Which of the following can be used in the management of a patient with oral lichen planus?

1. Prednisone

2. Clobetasol

3. Methylprednisolone

4. Fluocinamide

A. 1, 2, 3

B. 1 and 3

C. 2 and 4

D. 4 only

E. All of the above

Rationale

Dentists in clinical practice will regularly encounter patients with oral lichen planus (OLP). The oral form of lichen planus occurs more frequently than the cutaneous one and is more persistent and more resistant to treatment. Three different types of lesions of OLP are seen. Reticular OLP is the commonest but least severe form, which presents as a white, striated (lace-like) lesion, usually of the buccal mucosa. Atrophic OLP lesions are red and inflamed. Erosive OLP shows signs of shallow ulcerations, which can range in size. This is the most severe form of the disease, which causes considerable pain and interferes with eating, speech and quality of life.

There is no cure for OLP. Treatment is directed towards symptomatic relief of discomfort by use of topical corticosteroids. Topical agents such as fluocinamide 0.05% or clobetasol can be applied up to four times daily. In severe cases of erosive lesions, which are large, painful and debilitating for the patient and which are unresponsive to topical agents, systemic steroids may be required. In most cases, treatment is effective in reducing symptoms and inflammation and promoting healing of ulcerations.

REFERENCE

1.Chainani-Wu, N., Silverman, S. et al. Oral lichen planus. JADA; 132:901-909. 2001.

2.Edwards, P.C., Kelsch, R. Oral Lichen Planus: Clinical presentation and management. J Can Dent Assoc 68:494-499. 2002.

Answers to June 2004 SLSA Quiz

21. D

22. A

23. B

24. B

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