Self Learning, Self Assessment 2006 (September 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 33

Adjunctive orthodontics by the general practitioner facilitates disease control.

Adjunctive orthodontics by the general practitioner should be completed within six months.

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

In recognizing the greater demand of adult patients for orthodontics, the general practitioner has assumed a very important role. Adult care has been divided into two categories, viz. adjunctive and comprehensive. Adjunctive care to facilitate disease control and restore function is considered the general practitioner’s task. There are suggested restrictions, however. The work should involve less than the full arch and the estimate of time for completion of the tooth movement should be six months or less. Examples of this work include both incisor alignment and single tooth extrusion, the former facilitating plaque control in management of both caries and periodontal disease prevention, the latter performing a better crown/root ratio and a more vertical orientation for occlusion.

Comprehensive treatment performed by the specialist aims at ideal occlusion with appliances covering full arches and treatment time of eight to 36 months. Types of problems here are exemplified in the open bite, deep bite, Class II and Class III malocclusions, and skeletal excess or deficiency. The role of the general practitioner is to identify the adult patients who might benefit from this comprehensive care.

REFERENCE

Buttke, T.M., Proffit, W.R. Referring adult patients for orthodontic treatment. JADA. 130:73-79, 1999.

QUESTION 34

When measuring bone loss on conventional radiographic and digital bitewing images, measurements on digital images are consistently greater.

By using a combination of periapical and bitewing digital images, measurement of bone loss can be as accurate as that measured on conventional periapical and bitewing radiographs.

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

Alveolar bone loss associated with periodontal disease has traditionally been detected on conventional bitewing (BW) and periapical (PA) intraoral radiographs. Newer systems, e.g. digital radiography, offer various advantages over conventional radiography. In a study of 25 patients with periodontal disease, all patients had conventional radiographs with long cone paralleling techniques for PAs and standard BWs with paper sleeve and bite tab. A complete set of direct digital radiographs that matched was also obtained. Measurements of the distance from the CE junction to the interproximal alveolar crest were compared for a total of 857 matched PA sites and 315 matched BW sites.

The average bone loss measured on digital BW images was 0.3mm greater than that of conventional radiographs. Digital radiographs had consistently higher readings. More bone loss was seen on the digital radiograph in the posterior mandibular region; other areas matched with conventional radiographs. The average value obtained with PA radiographs did not differ between the two methods overall, but when looked at by sextant, the measure of maxillary bone loss was less with digital images than conventional. When comparing conventional and digital radiography, overall agreement in measurements from PAs was 84%, from BWs 86%. Analysis revealed that the small increase in bone loss as measured on digital radiographs categorized teeth as diseased in a much larger number of sites.

Thus, conventional and digitalized radiographs are not comparable and digitalized radiographs cannot be recommended for measuring alveolar bone loss since to do so will result in an incorrect diagnosis.

REFERENCE

Khocht, A., Janal, M. Harasty, L., et al. Comparison of direct digital and conventional intraoral radiographs in detecting alveolar bone loss. J Am Dent Assoc. 134:1468-1475. 2003.

QUESTION 35

Contraindications to immediate loading of an implant are

1. metabolic disease.

2. inadequate bone volume.

3. poor bone density.

4. clenching habit.

A. 1, 2, 3

B. 1 and 3

C. 2 and 4

D. 4 only

E. All of the above

Rationale

Immediate loading of dental implants implies that the occlusal surfaces and implants are loaded at the time of surgery with a provisional or definitive restoration. Both the edentulous mandible and the single anterior tooth restoration are candidates for implants with immediate loading.

Edentulous mandibles restored by an overdenture are the least at risk to occlusal overload in the immediate method and four or more implants are recommended. For successful outcome, there should be moderate bone height and width into which screw-type implants at least 10 mm long are inserted between the mental foramina, then splinted.

Contraindications to an immediate loading protocol include severe metabolic diseases, inadequate bone volume, poor bone density, and severe parafunction (e.g., bruxing, clenching).

REFERENCE

Misch, C.E., Hahn, J., Misch, C.M., et al. Workshop guidelines on immediate loading in implant dentistry. J Oral Implantology. 5:283-288, 2004.

QUESTION 36

The first radiographic sign of early periodontitis is fuzziness of the lamina dura at the crest of the septum.

After dental prophylaxis, there is a major alteration in the bacterial composition of the gingival crevice.

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

Periodontal diseases arise from bacterial infection around the teeth, triggering an inflammatory response. Diagnosis of periodontitis is made when there is evidence of attachment loss between the tooth and supporting tissues resulting in a pocket. On probing for pocket depth, bleeding is elicited.

Radiographic evidence initially shows as a fuzziness of the lamina dura at the mesial and distal aspects of the crest of the interdental septum. This is followed by a cratering of the crest as calcium salts are lost from the bone by osteoclastic activity and finally by a loss in the height of the interdental crest.

A recent study examined the microfloral changes in patients after dental prophylaxis. Such regular care provides a measurable reduction in the signs of gingivitis, and this study showed that, of 40 identified bacteria, there was a reduction in total numbers, but little change in the composition. It further suggested that the microbia of periodontitis are more specific and that bacterial samplings will not help the diagnosis of periodontitis.

It would appear, however, that sampling of inflammatory markers such as prostaglandins and cytokines from within the gingival crevicular fluid, help both in diagnosing and identifying people at risk to periodontal disease.

REFERENCES

1.Champagne, C.M., Buchanan, W., Reddy, M.S., et al. Potential for gingival crevice fluid measures as predictors of risk for periodontal diseases. Periodontol 2000. 31:167-180, 2003.

2.Goodson, J.M., Palys, M.D., Carpino, E., et al. Microbial changes associated with dental prophylaxis. JADA. 135:15
59-1564, 2004.

Answers to the August 2006 SLSA Questions

29. B

30. C

31. B

32. E

Funding for the SLSA program has been provided by: Colgate

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