Stakeholder Perception of the Professional Role and Competence of Swedish Dental Hygienists: A Questionnaire and Interview Study.

OBJECTIVES: This study investigated stakeholder opinions on the competence and role of dental hygienists in Sweden. MATERIALS AND METHODS: A questionnaire was sent by e-mail to 94 stakeholders in eight Swedish counties. The survey queried the competence of recently graduated dental hygienists in skills in collaboration, communication, and problem-solving, and in clinical skills. In addition, 10 stakeholders from different Swedish dental organizations agreed to one-on-one deep interviews. Open-ended questions focused on dental hygienist competence to perform dental hygienist skills and tasks and to collaborate with other dental professionals and health-care professionals. Further topics concerning the dental hygienist included their future role and working in other European countries. The interviews were transcribed and then coded using qualitative conventional content analysis methods. RESULTS: The stakeholder consensus in both the questionnaires and the interviews was that the dental hygienist profession is essential to modern dental care. The professional knowledge possessed by dental hygienists is unique and their role has developed and broadened over the years. Furthermore, the qualitative content analysis of the deep interviews identified a core category: The dental hygienist is an important profession for good oral health. CONCLUSION: Dental hygienists, responsible for prevention and oral health promotion, are an important members of the modern dental team. The need for dental hygienists to collaborate with other dental and general health-care professionals to meet the future demands of society will increase.

Influence of culture conditions on porphyrin production in Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis.

BACKGROUND: Increasing antibiotic resistance among pathogens has raised the demands for new treatment methods such as antimicrobial photodynamic therapy (aPDT) and phototherapy (PT). Experiments for investigating the effects of these methods are often performed in vitro, but the procedures for cultivation of microbes vary between different studies. The aim of this study has been to elucidate how the profile of endogenously produced porphyrins differs by changing the variables of bacteria culturing conditions. METHODS: Two oral pathogens, Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis, were selected as model organisms. The contents of porphyrins and heme in the bacteria were analysed with liquid chromatography-tandem mass spectrometry when bacteria was cultivated for different lengths of time (3-9 days), upon passaging as well as when growth medium were supplemented with or without horse blood. RESULTS: Both porphyrin and heme content in A. actinomycetemcomitans are highly affected by the age of the culture, and that the porphyrin profiles changes during cultivation. When cultivated colonies of A. actinomycetemcomitans were passaged onto a new, fresh growth medium a large change in porphyrin content occurred. Additional porphyrins were detected; uroporphyrin and 7-carboxylporphyrin, and the total porphyrin content increased up to 28 times. When P. gingivalis was grown on blood containing medium higher concentrations of protoporphyrin IX (2.5 times) and heme (5.4 times) were quantified compared to bacteria grown without blood. CONCLUSIONS: This study demonstrate that there is a need for more standardized culturing protocols when performing aPDT and PT experiments in vitro to avoid large variations in porphyrin profiles and concentrations, the aPDT/PT target compounds, depending on the culturing conditions.

Determination of porphyrins in oral bacteria by liquid chromatography electrospray ionization tandem mass spectrometry.

Biofilms in the oral cavity can be visualized by fluorescence and a common assumption is that the endogenously produced porphyrins in certain bacteria give rise to this fluorescence. Porphyrin content in oral bacteria has been sparingly investigated, and non-selective detection techniques such as utilizing the Soret fluorescence band of porphyrins are often used. In the present study, a quantitative and selective method for the determination of porphyrins in oral bacteria has been developed and validated using high performance liquid chromatography-tandem mass spectrometry. Lysis of bacteria using Tris-EDTA buffer together with ultrasonication showed high microbial killing efficiency ≥99.98%, and sample clean-up using C18-solid phase extraction resulted in low matrix effects ≤14% for all analytes. Using this method, the porphyrin content was determined in the two oral pathogens Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis, as well as for baker's yeast, Saccharomyces cerevisiae. Uroporphyrin, 7-carboxylporphyrin, 6-carboxylporphyrin, coproporphyrin, and protoporphyrin IX were identified in the investigated microorganisms, and it was shown that the porphyrin profile differs between the two bacteria, as well as for S. cerevisiae. To our knowledge, this is the first time the porphyrin profile has been determined for the bacterium A. actinomycetemcomitans.