2004 Self Learning Assessment (October 01, 2004)

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 37

Preoperative prescriptions of ibuprofen will reduce post-operative pain.

Combining analgesic drugs with different times of onset improves the range of analgesia.

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

New strategies in pain management allow varied options of treatment. For example, preoperative prescribing of some analgesics such as ibuprofen will reduce postoperative pain reaction. Combining analgesics with action at both peripheral and central sites provides comparable analgesia at lower and more tolerable doses of the component drugs. Additionally, combining drugs with different times of onset improves the range of analgesia. Side effects and recovery times are reduced. Studies with opioid/acetaminophen combinations and NSAID/opioid combinations have proved very effective in control of acute dental pain.

Opioids such as codeine 15mg, 30mg, and 60mg can be combined with aspirin, acetaminophen or ibuprofen and produce a much more effective control of pain than with either alone. Ibuprofen 400mg and oxycodone 10mg provides a faster relief of dental pain than ibuprofen 400mg alone. NSAIDs also allow for a significant reduction of opioids and thus opioid side effects are minimized.

REFERENCE

Melisch, D.R., Efficacy of combination analgesic therapy in relieving dental pain. JADA 133:860-871, 2002.

QUESTION 38

Following extraction of a maxillary central incisor to be later replaced by an implant, which of the following would provide the best aesthetic result in the long term?

1. An alveolar bone crest 6mm from the free gingival margin.

2. A provisional fixed bridge with the pontic extending into the socket.

3. A removable stay-plate with tooth replacement.

4. A thick gingival biotype.

A. 1, 2, 3D. 4 only

B. 1 and 3E. All of the above

C. 2 and 4

Rationale

A diagnostic evaluation of the failing tooth in its surrounding tissue is essential. This starts with radiographic assessment. The tooth should be free of periapical and interradicular pathosis. Normal interproximal bone height should be 1-2mm apical to the cemento-enamel junction of the adjacent teeth. Soft tissue evaluation is also important for aesthetics. This involves examination of the gingival scallop and the gingival biotype. The scallop is defined as the distance between the mid-facial and interproximal tissue height, the normal being 4-5mm. Gingival biotype is either thick or thin, and thick provides for better aesthetics since thin is prone to recession and interproximal tissue loss. Also in soft tissue assessment is the interdental papilla, the height of which is determined by the position of the underlying osseous crest. Normal measurement is 4.5 mm from the bone crest-the greater the distance the greater the risk of tissue loss after extraction. Hard tissue assessment is also necessary. Studies have shown a relationship between the gingiva and underlying bone, which applies to both the natural dentition and implants. Normal relationship between the free gingival margin and the bone crest is 3mm on the facial aspect and interproximally 4.5mm. Use of an immediate provisional pontic after extraction preserves the surrounding tissues and thus improves post-implant aesthetics. The pontic should be ovate, extend into the socket, attached to a provisional “fixed bridge,” and made non-functional. Although a stay-plate can be used instead of a “fixed bridge,” the movement of the plate tends to impinge and irritate the soft tissues.

REFERENCES

1.Conte, G.J., Rhodes, P., Richards, D. et al. Considerations for anterior implant aesthetics. CDA Journal. 30:528-534. 2002

2.Kao, R.T. and Pasquinelli, K. Thick vs. thin gingival tissue: a key determinant in tissue response to disease and restorative treatment. CDA Journal. 30:521-528. 2002.

QUESTION 39

Type I hypersensitivity to latex is an immediate or anaphylactic reaction.

Type IV hypersensitivity to latex is delayed and localized to the area of contact.

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

Type I hypersensitivity manifests as an immediate or anaphylactic reaction. Type IV reactions involve delayed hypersensitivity and are usually localized to the area of contact. Contact dermatitis, e.g., eczema (Type IV) is the most common expression of latex allergy. In the dental office, immediate hypersensitivity reactions (Type I) have also been elicited by exposure to rubber gloves, rubber dams and dental prophylaxis cups. Various textbooks and articles have suggested that cartridges for dental anaesthetics can induce allergy and should be avoided because of the latex in the diaphragm and the stopper. A literature search for the period 1966-2001 provided some evidence that latex allergen can be released into pharmaceutical solutions contained within vials by either penetration or through a direct contact with natural latex stoppers. However, there were no reports of studies or cases in which a documented allergy was due to the latex component of dental local anaesthetic cartridges.

Since numerous items used daily in dentistry have the potential to induce an allergic reaction in a patient with latex hypersensitivity, high-risk patients (Type I) should be treated in a hospital setting.

REFERENCE

Shojaei, A.R., Haas, D.A. Local anaesthetic cartridges and latex allergy: A literature review. J Can Dent Assoc. 10:622-626. 2002.

QUESTION 40

The principal effect(s) of obstructive sleep apnea which occur(s) during apneic periods is/are

1. increased cardiac output

2. arrhythmias

3. decreased blood pressure

4. decreased oxyhaemoglobin saturation

A. 1, 2, 3D. 4 only

B. 1 and 3E. All of the above

C. 2 and 4

Rationale

Obstructive sleep apnea (OSA) is characterized by repetitive episodes of upper airway obstruction that occur during sleep, usually associated with a reduction in oxygen saturation, daytime sleepiness, and snoring. The obstructive episodes are of two types-apnea and hypopnea. Apneas are periods of total airway obstruction, which last for more than 10 seconds. Hypopneas are partial airway obstructions. The principal cardiovascular effects of OSA, which occur during apneic periods are reduction in cardiac output, arrhythmias and nocturnal hypertension, with a decreased oxyhaemoglobin saturation. If not treated, OSA will increase the mortality rate. Deaths are most commonly attributed to myocardial infarction or cerebrovascular accident. Death may also be associated with pulmonary oedema, pulmonary hypertension and obstructive airway disease. Daytime sleepiness is also a significant factor in acute death from OSA because of falling asleep while driving or operating machinery. Obesity and OSA are inextricably linked. Obese patients find it difficult to exercise and have increased cardiovascular mortality. Fat becomes deposited in the soft palate, larynx and neck and this increases the degree of airway obstruction.

Diagnosis of OSA requires extensive investigation, including a sleep study. Treatment may vary from the simple such as a change in sleeping position to more extensive procedures. Oral appliances to reposition the mandible and soft tissues for increased oropharyngeal space, or CPAP (positive air pressure directed down the airway by a machine via the nose with the mouth closed) can be used. Other modalities are hard and soft tissue surgical procedures.

REFERENCE

Sherring, D., Vowles, N. Antic, R. et al. Obstructive sleep apnea: A review of the Orofacial Implications. Oral Health. Oct. 71-94. 2002. Re
printed from Australian Dental Journal. 46:3. 2001.

Answers to September 2004 SLSA Quiz

33. A

34. E

35. D

36. B

The 2004 15-question Quiz for CE points appears in the November issue along with instructions and reply card. Answers must be received by December 31st to be eligible.

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