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

QUESTION 25

The primary objective of splinting subluxed teeth is

1. maintenance of function.

2. protection of soft tissues.

3. healing of alveolar bone.

4. regeneration of the periodontal ligament.

A. 1, 2, 3

B. 1 and 3

C. 2 and 4

D. 4 only

E. All of the above.

Rationale

The primary objective of splinting subluxed teeth is protection and healing of the injured tissues. This includes alveolar bone and soft tissues and especially the periodontal ligament. If treatment is not rapid the periodontal ligament will fail to heal because of poor regenerative capacity. Therefore, a splint is called for immediately, but it should allow for a degree of tooth movement and not interfere with full excursion of the jaw. In this way, regeneration of the periodontal ligament fibres is encouraged. Many splints are available but the two most easily applied are a wire composite splint and a self etching and bonding material splint. Both use a soft wire support with composite resin or bonding material for attachment to the injured and adjacent teeth, the splint to be in place for 10 days to 3-4 weeks. A splint retention for over 4 weeks is contraindicated.

References

1. Kenny, D.J., Barrett, E.J. Emergency trauma: Treating the unexpected. Oral Health 97 – 116, 2006.

2. vonArx, T. Splinting of traumatized teeth with focus on adhesive techniques. Oral Health 85 – 94, 2006.

QUESTION 26

Which of the following is most effective for remineralization of active primary root caries lesions?

A. Chlorhexidine varnish.

B. Ozone exposure.

C. A mouth rinse of amine fluoride and potassium fluoride in combination with a fluoride toothpaste.

D. Meticulous oral hygiene in combination with stannous fluoride toothpaste.

Rationale

Different preventive strategies have been tested to reverse and control Primary Root Caries Lesions (PRCL) such as meticulous oral hygiene in combination with fluoridated toothpaste and fluoride mouth rinses. Antibacterial methods with chlorhexidine varnish and ozone treatment have also been tested.

A clinical trial was conducted to assess the effect on PRCL of a twice daily use of a fluoride mouth rinse containing 250 ppm F as amine fluoride and potassium fluoride (AmF/KF), compared to a placebo mouthrinse solution without fluoride, both in combination with a fluoride toothpaste. Results showed that rinsing with AmF/KF twice daily, in combination with a fluoride toothpaste, significantly remineralized active soft and leathery PRCL, as well as reducing substantially tooth sensitivity.

Reference

1. Petersson, L.G., Hakestam, U., Baigi, A. et. al. Remineralization of primary root caries lesions using an amine fluoride rinse and dentifrice twice a day. American Journal of Dentistry 20 : 93 – 96, 2007.

QUESTION 27

Oral microorganisms are controlled by

1. swallowing.

2. lysozymes in saliva.

3. histatins in saliva.

4. mucin.

A. 1, 2, 3

B. 1 and 3

C. 2 and 4

D. 4 only

E. All of the above

Rationale

Numerous bacteria are present in saliva and they are removed from the mouth mainly by swallowing. When hyposalivation occurs, patients will develop halitosis from reduced bacterial clearance and their subsequent proliferation. Saliva contains several antibacterial factors such as “lysozyme” which can repel transient bacterial invaders and “histatins” which have strong antifungal activity.

Many types of salivary proteins, such as mucin inhibit bacterial and HIV infections. Because saliva is supersaturated with tooth minerals, it is the “store” for the remineralisation process which is constantly occurring between meals.

Reference

1. Dawes, C. Salivary flow patterns and the health of hard and soft oral tissues. JADA 139 : 18S – 24S, 2008.

QUESTION 28

Ingestion and aspiration of avulsed teeth is more frequently seen in

1. young children.

2. mentally challenged patients.

3. physically challenged patients.

4. cases of maxillofacial trauma.

A. 1, 2, 3

B. 1 and 3

C. 2 and 4

D. 4 only

E. All of the above.

Rationale

Ingestion and aspiration of avulsed teeth have been reported in maxillofacial trauma, young children and physically and mentally challenged patients. Dentists should suspect that any avulsed or extracted tooth not found in the oral cavity has been aspirated or ingested. The same pertains to crowns, clamps and other objects. Early diagnosis with neck, chest and abdominal x-rays is essential.

Reference

1. Elgazzar, R.F., Abdelhady, A.I. and Sadakah, A.A. Aspiration of an impacted lower third molar during its surgical removal under local anaesthesia. Int. J. Oral Maxillofac. Surg. 36: 362 – 364, 2007.

Answers to the June 2010 SLSA questions:

21. E

22. C

23. E

24. E

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