2003 Self Learning Assessment (April 01, 2003)

The SLSA program is based on current, referenced literature and consists of 40 questions, answers, rationales and references. Answers appear at the end of each quiz.

Dentists who complete the 15 question quiz in the November, 2003 issue of Oral Health may be eligible to receive continuing education points. The names and license numbers of all who complete the quiz will be forwarded to their respective provincial licensing authorities.

QUESTION 13

Control of tooth mobility by splinting in the initial phase of treatment of periodontal disease enhances the prognosis of hypermobile teeth.

Increased mobility is not always found in teeth showing severe periodontal breakdown.

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 review by Giargia and Lindhe dispels many myths regarding tooth mobility and periodontal disease. Their study, using a splitmouth technique where one half of the mouth was splinted and the other not, failed to show any difference in the mobility ratings of teeth after the initial phase of treatment was completed and the splints removed. Although increased tooth mobility is a risk factor in progressive periodontitis, increased tooth mobility is not always found in teeth with severe periodontal breakdown.

A further point is that tooth mobility, which remains the same, has no obvious effect on the inflammatory lesions associated with periodontal disease. However, increasing mobility in a progressive manner over time can be regarded as a contributing factor in progressive periodontitis.

Provided the inflammatory process is controlled with adequate oral hygiene, teeth with stable hypermobility may be in adequate function for a long time.Control of tooth mobility during the initial phase of healing following treatment does not enhance the outcome therapy.

REFERENCE

1. Giargia, M., Lindhe, J. Tooth mobility and periodontal disease. J Clin Periodontol 24:785-795. 1997.

QUESTION 14

When planning an anterior crown, which of the following is/are essential for maximum aesthetics and periodontal health?

1. The labial preparation edge should be placed no more than 0.5 mm into the crevice.

2. The gingiva must be free of inflammation.

3. The embrasure space must be appropriately contoured.

4. The restoration margin must be no more than 2 mm from the alveolar crest.

A.1, 2, 3D. 4 only

B.1 and 3E.All of the above

C.2 and 4

Rationale

In some instances where there is extensive caries or crown fracture, placement of a crown margin on solid tooth structure can result in violation of the biological width needed for health and stability of the periodontium. The distance from a restoration margin to the alveolar crest should be at least 3 mm. This is made up of 1 mm connective tissue attachment, 1 mm of junctional epithelium and 1 mm of gingival sulcus. In an anterior crown, the labial edge of the preparation can invade the crevice up to 0.5 mm, but no more, and this for aesthetics only. Where the gingival margin of the tooth to be restored would violate the biological width, crown lengthening should be considered. Frequently, a combination of orthodontic extrusion and surgical crown lengthening can be planned; this will minimize the need for resective therapy of adjacent teeth. In addition, orthodontic extrusion allows for a regaining of the lost height of the interdental papillae.

Donovan argues that the essential requirement for crown aesthetics is immediate control of soft tissue inflammation, whether it be plaque or trauma induced. This argument is made for soft tissue care during tooth preparation, for provision of temporary restorations of high quality, elimination of excess temporary cement and use of a waiting period to allow the soft tissue to heal after therapy.

The shape of the embrasure space must be designed with a contour to provide aesthetics and to promote continued periodontal health.

REFERENCES

1.Jordensen, M. and Nowzari, H. Aesthetic crown lengthening. Periodontology 2000. 27:45-58. 2001.

2.Donovan, T.E., and Cho, G.C. Predictable aesthetics with metal-ceramic and all-ceramic crowns: the critical importance of soft tissue management. Periodontology 2000. 27:121-130. 2001.

QUESTION 15

Which of the following could be harmful to a pregnant woman or her foetus?

1.Use of Aspirin (acetylsalicylic acid).

2.Periodontal infection.

3.Use of Valium (diazepam).

4.Fluoride supplements

A.1, 2, 3D.4 only

B.1 and 3E.All of the above

C.2 and 4

Rationale

There would appear to be an association between periodontal infection in the mother and preterm birth and low birth weight. Studies are underway to develop additional data. In the meantime, it would be appropriate to advise expectant mothers on the needs of oral hygiene for control of both gingivitis and periodontitis. Diazepam (Valium) has been associated with birth defects such as cleft lip and palate and it should therefore be avoided in a pregnant patient. For the same reason, barbiturates should not be administered.

Non-steroidal anti-inflammatory drugs (NSAIDs) such as acetylsalicylic acid and ibuprofen are contraindicated in the pregnant patient. They increase the length of pregnancy, impair platelet function, and prolong bleeding time, which at the end of pregnancy can introduce risk of antepartum and postpartum haemorrhage.

The value of prenatal fluoride supplements for the developing foetal dentition is questionable, since no research has shown any benefits. Therefore, the major pediatric societies do not recommend their use.

REFERENCES

1.Miller, M.C. The pregnant dental patient. Oral Health. March 9-13. 2001.

2.Jeffcoat, M.K., Genrs, N.C., Reddy, M.S., et al. Periodontal infection and pre-term birth. Results of a prospective study. JADA 132:875-880. 2001.

QUESTION 16

Triclosan is

1.a broad-spectrum antibacterial agent.

2.used in toothpastes and mouthwashes.

3.able to reduce plaque accumulation.

4.not effective against gram positive microorganisms.

A.1, 2, 3D.4 only

B.1 and 3E.All of the above

C.2 and 4

Rationale

Triclosan is a recognized broad-spectrum antibacterial agent which is effective against both gram positive and gram negative organisms. The primary site of action is the bacterial cytoplasmic membrane. In bacteriostatic concentrations, Triclosan causes cytoplasmic disorganization of the bacterial cell membrane and leakage of the cell contents.

Over the last decade, Triclosan has been incorporated into both mouthwashes and toothpastes. Many clinical studies have shown its effectiveness in reducing plaque accumulation, gingivitis and calculus formation.

Colgate Total toothpaste contains 0.3% Triclosan, 2% polyvinylmethyl ether maleic acid (PVM/MA) copolymer and 0.243% of sodium fluoride in a silica base. The combination of PVM/MA with the Triclosan causes a greater uptake of the antibacterial agent to enamel and buccal epithelial cells, thus prolonging the action.

Additional to the benefits mentioned, Colgate Total Plus Whitening toothpaste was found to be effective not only in stain removal but also in management of halitosis. For stain removal, it was compared with two dentifrices, Crest Multi-Care Advanced Cleaning Toothpaste and Colgate Winterfresh Gel Fluoride toothpaste. Colgate Total Plus Whitening toothpaste exhibited statistically significant reductions in stain removal compared to the others.

Recently, a liquid dentifrice containing Triclosan copolymer and sodium fluoride was tested according to ADA guidelines for clinical evaluation of antiplaque/ antigingivitis products. Results confirmed the efficacy of such a dentifrice in reducing both plaque and gingivitis.

REFERENCES

1.Volpe, A.R., Petronei, M.E., Prencipe, M., et al. The efficacy of a dentifrice with caries, plaque, gingivitis, tooth whitening and oral malodor benefits. J Clin Dent 13:55-58. 2002.

2.Petrone, M.E., DeVizio, W., Chaknis, P., et al. A six-
week clinical study to compare the stain removal efficacy of three dentifrices. J Clin Dent 13:91-94. 2002.

3.Triratana, T., Rustogi, K.N., Volpe, A.R., et al. Clinical effect of a new liquid dentifrice containing Triclosan/copolymer on existing plaque and gingivitis. JADA 33:219-225, 2002.

Answers to March 2003 SLSA Quiz

9. A

10. E

11. E

12. C

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