Radiographic and clinical signs of periodontitis and associated bacterial species in a Swedish adolescent population.

BACKGROUND: Periodontitis in adolescents has historically been rare in the Nordic countries but could be expected to increase due to changing demographics. The primary aim was to cross-sectionally examine the presence of radiographic bone loss in adolescents in Västerbotten County, Sweden. The secondary aim was to compare periodontal and microbial parameters, as well as demographic patterns, between controls without bone loss and cases with bone loss. METHODS: Adolescents born in 2001 who had a dental examination in 2016 (n = 1656) were screened for proximal bone loss using bitewing radiographs taken during dental examinations (2014-2016). Individuals exhibiting proximal bone loss (>2 mm) were invited to participate in a complete periodontal examination. Subgingival plaque and saliva were also sampled. For each adolescent with bone loss, two healthy individuals as controls were examined. Selected bacterial species in saliva and subgingival plaque were examined by quantitative PCR. The subgingival plaque samples were also analyzed via cultivation technique. RESULTS: Proximal bone loss was identified in 24 individuals (1.45%) based on the radiographs. Thirteen of these cases were periodontally examined and matched with 26 controls. Most cases were diagnosed with periodontitis (12/13 [92%]), whereas none of the controls had periodontitis. Higher concentrations and higher prevalence of the bacteria Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and Filifactor alocis were generally found in the cases. CONCLUSION: The results suggest that periodontitis is increasing among adolescents in Sweden because of demographic differences (an increasingly heterogenous population), and emphasize the importance of radiographs for early detection of this disease.

Characterization of Aggregatibacter actinomycetemcomitans Serotype b Strains with Five Different, Including Two Novel, Leukotoxin Promoter Structures.

The JP2 genotype of A. actinomycetemcomitans, serotype b has attracted much interest during the past three decades due to its close association with periodontitis in young individuals and the enhanced expression of a leukotoxin (LtxA). A typical feature of this genotype is a 530-base pair (bp) deletion in the ltxCABD promoter region controlling leukotoxin expression. In the present work, we have characterized serotype b strains with four additional promoter types. Two novel types have been recognized, that is, one with a 230-bp deletion and one with a 172-bp duplication. Moreover, a strain with a 640-bp deletion and three strains with a full-length promoter, including the type strain Y4, were included in the present study. The seven strains were characterized by multi locus sequence typing (MLST) and arbitrarily primed polymerase chain reaction (PCR) and assessed for LtxA production. MLST showed that the strains with the non-JP2-like deletions represented distinct monophyletic groups, whereas the JP2 strain, HK1651, represented a separate branch. LtxA production was high in all three strains with a promoter deletion, whereas the other four strains showed significantly lower levels. It can be concluded that the genetic characterization and determination of LtxA production of A. actinomycetemcomitans isolates from individuals with periodontitis can contribute to the identification of novel virulent genotypes of this bacterium.

Caries as experienced by adult caries active patients: a qualitative study.

Objective: In the western world, increased oral health has resulted in a skewed occurrence of caries disease where relatively few individuals now account for most caries disease. This study examines how adults with recurrent caries activity experience caries disease and treatment.Materials and methods: The study is based on qualitative data from individual interviews, which were subjected to qualitative content analysis. The interviews were semi-structured and thematic and an interview guide was used that consisted of two main areas with open ended questions. Meaning units were condensed and labelled with a code which preserved the core content of the reduced text. Codes were assigned to different subcategories according to their similarities or differences. Subcategories formed categories which describe the manifest content of the text.Results: The domain "experience with caries" consisted of four subcategories that formed the main category Caries - an unwelcomed acquaintance. The domain "experience with caries treatment" consisted of three subcategories that formed the category Caries treatment - pain for gain.Conclusion: Comprehensive non-operative treatment and close follow-ups should precede restorations; this would probably gain insight in how to avoid new cavities to a greater extent. If to be supportive, information and advice about self-care given to individuals with recurrent cavities should be delivered with respect to the patient's feelings about their experience of dental caries.