Self Learning, Self Assessment 2006 (October 01, 2006)

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

Dentists who complete the 15 question quiz in the November, 2006 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 37

In indirect pulp treatment of primary molars, a successful outcome is influenced by the

A. gender of patient.

B. age of patient.

C. caries risk.

D. operator skill and experience.

E. None of the above.

Rationale

Indirect pulp capping (IPC) was advocated more than 200 years ago by Fauchard, who recommended retention of some caries because, if caries were removed completely, a pulp exposure would occur. The term IPC was recently replaced by the term Indirect Pulp Treatment (IPT). One hundred thirty-two patients were selected to test the value of IPT; 187 primary posterior teeth were so treated. The patients were followed clinically and radiographically for a time ranging from two weeks to six years. The overall success rate was 95%. The use of a base over a calcium hydroxide liner significantly increased the success rate. A stainless steel crown as a restoration was significantly better in registering a successful outcome than amalgam. Primary first molars failed more frequently than second molars, but there was no significant difference between maxillary and mandibular teeth. Gender, age of patient, caries risk and operator’s skill and experience had no significant effect on the success rate. Indirect pulp treatment should therefore be considered as an alternative to pulpotomy in the management of deep dental caries in primary molars without signs of pulpal degeneration.

REFERENCE

Al-Zayer, M.A., Straffon, L.H., Feigal, R.J., et al. Indirect pulp treatment of primary posterior teeth: a retrospective study. Pediatric Dentistry. 25:29-36, 2003.

QUESTION 38

If accidental wound exposure to HIV-contaminated material should occur, which of the following should be your first line of action?

A. Seek immediate advice from a hospital department of infectious diseases.

B. Record date, time and description of exposure and then seek advice from a hospital department of infectious diseases.

C. Promote bleeding at site of wound, wash and disinfect.

D. Disinfect area, record the date, time, and description of exposure, and seek advice from a hospital department of infectious diseases.

Rationale

When universal precautions are followed, routine dental treatment of HIV-infected patients presents little risk to either patient or dentist but if a cut or puncture wound occurs, the guidelines to follow are:

* Press area to increase bleeding.

* Wash wounds thoroughly with soap and water.

* Disinfect.

* Record date, time, and description of exposure.

* Seek advice from a hospital department of infectious diseases (within 24 to 48 hours) to evaluate the need for postexposure prophylaxis (PEP):

* With appreciable risk, PEP is recommended.

* With low risk, PEP should be considered.

* With minimal risk, PEP is not recommended.

The risks faced by dental staff are extremely low, and refusal of treatment to these patients is not justified.

REFERENCE

Campo-Trapero, J., Cano-Sanchez, J., del Romero-Guerrero, J., et al. Dental management of patients with immunodeficiency virus. Quintessence Int. 34:515-525, 2003.

QUESTION 39

Accurate location of an unerupted mandibular third molar root apex to the mandibular canal is best determined by

A. panoramic radiography.

B. periapical radiography.

C. lateral view radiography.

D. CT scan.

Rationale

The panoramic radiograph (PR) allows an initial evaluation of possible problems associated with an impacted tooth. A recent study assessed the accuracy of five radiographic markers on the PR in predicting contact between the mandibular canal and the third molar. These markers were:

* superimposition of the tooth on the canal

* increased radiolucency at the tooth apex

* interruption of the radiopaque border of the canal

* diversion of the canal

* narrowing of the canal.

Three of these had a high predictive value for relationship between the tooth and the canal, viz. narrowing of the canal, increased radiolucency and interruption of the radiopaque border of the canal. Increased radiolucency around the tooth apex was the best predictor and practitioners should be aware of this.

Where two or more markers were identified, contact between the mandibular canal and the tooth was found. The number of cases that showed a true relationship between the tooth and the canal tended to involve teeth in a horizontal position, but when no increased radiolucency was seen, the risk of a true relationship decreased. The number of cases with diversion of the canal was too small to draw any conclusion. When superimposition is noted on the PR, a periapical film is usually sufficient to determine position, but when markers are found that carry a high predictive value for a true relationship between tooth and canal, consultation is advised and a CT scan may be required as this is the most accurate method.

REFERENCE

Monaco, G., Montevecchi, M., Alessandri, G., et al. Reliability of panoramic radiography in evaluating the topographic relationship between the mandibular canal and third molars. JADA. 135:312-318, 2004.

QUESTION 40

Which of the following antibiotic regimes is/are recommended for patients with recurrent periodontitis who are not responding to mechanical treatment?

1. Ciprofloxin250mg bid for 8 days

2. Doxycycline200mg q.d. for 21 days

3. Clindamycin300mg tid for 5 days

4. Metronidazole500mg tid for 8 days

A. 1, 2, 3

B. 1 and 3

C. 2 and 4

D. 4 only

E. All of the above

Rationale

A recent report examined the practice of use of antibiotics in treatment of periodontitis. Although microbial etiology provides a rationale for use of antibiotics, arguments are made against indiscriminate therapy. Prime candidates for such care are those patients who continue to show loss of periodontal attachment despite careful mechanical treatment. Recurrent or refractory periodontitis with resistant subgingival pathogens or impaired host resistance can benefit from systemic antibiotics. Patients with acute periodontal infections, such as periodontal abscess or necrotizing gingivitis/periodontitis, are also candidates for systemic antibiotic therapy.

The report suggests that if using antibiotics, the dentist should try to determine the pathogenic microbia of the subgingival pocket. These samples are to be collected by sterile paper point or curette.

Common antibiotic therapies are shown in the table below and selection should be made according to sensitivity testing:

Antibiotic	Adult Dosage
Metronidazole	500 mg/tid/8 days
Clindamycin	300 mg/tid/8 days
Doxycycline or minocycline	100-200 mg/qd/21 days
Ciprofloxin	500 mg/bid/8 days
Azithromycin	500 mg/qd/4-7 days
Metronidazole amoxicillin	250 mg/tid/8 days of each drug
Metronidazole and ciprofloxacin	500 mg/bid/8 days of each drug