B. Frode Hansen

Periodontal health and relative quantity of subgingival Porphyromonas gingivalis during orthodontic treatment

OBJECTIVE To examine periodontal changes and the relative quantity of subgingival Porphyromonas gingivalis during orthodontic treatment. MATERIALS AND METHODS The study subjects were recruited consecutively among malocclusion patients seeking orthodontic treatment. Group A comprised 28 subjects (17.6 ± 5.68 years of age) at the beginning of orthodontic treatment, and group B comprised 20 subjects (17.8 ± 4.49 years of age) at the end of orthodontic treatment. Plaque index (Pl.I), gingival index (GI), and probing pocket depth (PPD) were measured before and after appliance placement in group A and before and after appliance removal in group B. Real-time quantitative polymerase chain reaction was used to quantify P. gingivalis in subgingival plaque at each time point. RESULTS There was a significant increase in Pl.I and GI during the first 3 months of appliance placement but a significant decrease in Pl.I, GI, and PPD during the first 6 months after appliance removal. The carriage and relative quantity of subgingival P. gingivalis were high at the end of orthodontic treatment, and they decreased significantly after appliance removal. The amount of subgingival P. gingivalis after appliance removal (for a period of 6 months) was higher than the amount measured before appliance placement. CONCLUSIONS Fixed orthodontic treatment is conducive to dental plaque accumulation and gingival inflammation. In our study, after removal of orthodontic appliances, periodontal health improved, and the carriage and amount of subgingival P. gingivalis decreased. Nevertheless, the amount of subgingival P. gingivalis remained high for 6 months after appliance removal, and this finding might imply a potential risk to periodontal health in certain patients.

Oral roentgenologic findings in a Norwegian urban population

Orthopantomograms were taken of 111 subjects constituting a random sample of 35-year-old citizens of Oslo. The most frequent pathologic finding was marginal bone loss, which was found in seventy-one persons (64%). Fifty-one impacted and unerupted teeth in twenty-eight persons were seen, the third molars predominating. Ten retained roots were found in nine persons, and apical radiolucent areas were found on forty-four teeth in thirty-three persons. In addition to the pathologic findings, 101 endodontically treated teeth in fifty-five persons were observed.

Factors of importance for changes in dental caries among adults: A follow-up study of Oslo citizens from the age of 35 to 50 years

Eighty-one 35-year-old Oslo citizens examined in 1973 were reexamined after 15 years, to monitor changes in their caries situation expressed as carious surfaces (DS + DFS). Factors considered to be of importance for a change in the number of carious surfaces over this 15-year period were arranged under four items: environment, behavior, human biology, and health care organization. The results showed a slight but not statistically significant increase in the overall caries experience expressed as DMFS. A statistically significant reduction in DS + DFS from the age of 35 to 50 years was demonstrated. Despite this reduction 23% of the 50-year-olds had more carious surfaces than at age 35. The results indicate that the improvement in the number of untreated carious surfaces reported from many Western societies is also valid for adult Norwegians. However, this improvement is not shared by all. Multivariate analyses showed that behavioral factors had the greatest impact on the observed changes in dental health.