Research projects within Cariology, Endodontics, Periododontology, Prevention, Oral Microbiology and Oral Immunology. We specifically focus on the inflammatory pathogenesis of periodontal diseases, microbial etiology of common oral diseases (periodontitis, caries, root canal infections, and peri-implantitis), exploration of the oral microbiome, inter-connection between oral and general health, as well as new methods for the prophylaxis, diagnosis and treatment of oral infectious diseases.
Our goal is to perform cutting-edge research and education in oral health, to optimize prevention, diagnosis and treatment of common oral diseases, and contribute to the overall well-being.
Microbiome dynamics in oral health and disease
The aim of this research theme is to characterize the structural and functional composition of the oral microbiome. The specific aims include a) the identification of distinctive microbial patterns in oral health and oral infectious disease, such as dental caries, endodontic infections and periodontal and peri-implant disease, and b) the effect of the various treatment strategies on the dynamics changes of the site microbiome, towards the restoration of oral health. These studies involve analysis of biological samples obtained from clinical cohorts by conventional molecular and high-throughput technologies, such as next generation sequencing.
Georgios N. Belibasakis, Professor of Clinical Oral Infection Biology and Head of Division of Oral Diseases.
Oral biofilm ecology and interactions
This research theme aims at providing deeper insights to the ecology of oral biofilms and their intrinsic and extrinsic interactions. It is taken to understand the interaction between the individual microbial species with poly-microbial communities, the micro-environmental factors that drive their behavior, and their interaction with the oral cells/tissues in inducing a protective or destructive host response. These studies involve multi-species bacterial biofilm models grown in the laboratory. Among the scopes of this research is to test various antimicrobial modalities on the biofilms, as a preamble for validating candidate therapeutic interventions for future clinical application.
Georgios N. Belibasakis, Professor of Clinical Oral Infection Biology and Head of Division of Oral Diseases.
Chairside diagnostics for oral diseases
This research line has direct implication on patient diagnostics for oral infectious diseases. It aims at developing chair-side diagnostic tests for their implementation in clinical dental practice. It is based on developing saliva-based microfluidic assays for nucleic-acid detection of selected cariogenic and periodontopathogenic species, as well as protein bioassays for periodontal diseases. The back-bone of this research line is the Horizon2020 EU project DIAGORAS (www.diagoras.eu), in which Karolinska Institutet is a partner.
Georgios N. Belibasakis, Professor of Clinical Oral Infection Biology and Head of Division of Oral Diseases.
Inflammation and periodontal pathogenesis
Periodontology, periodontal Inflammation, periodontal microbiome, host-pathogen interactions, molecular microbial ecology, metaproteomics, systems biology, development of new antimicrobials, oral biofluid biomarkers.
Prof Bostanci´s group focuses on in vitro and in vivo analysis of host-pathogen interactions in the context of periodontal diseases. This research line involves a range of complementary disciplines and approaches, including clinical periodontology, immunology, microbiology, bioengineering, proteomics, metaproteomics and systems biology. The group aims to better understand periodontal homeostasis and the underlying mechanisms of inflammatory periodontal pathogenesis. The ultimate goal is to improve the quality of periodontal care delivered through early and accurate diagnosis, and development of innovative targeted therapeutic approaches.
Her laboratory has three main research directions in periodontology including:
- discovery of biomarkers of periodontal and systemic inflammation, in conjunction with multi- high-throughput “omic” technologies and systems biology approaches
- understanding potential links between periodontal disease and women's health
- deciphering how periodontal bacteria compete against each other by means of their specific virulence factors, and how the periodontal tissues are affected during such complex interactions
Nagihan Bostanci, Professor
Angelika Silbereisen, Postdoc
Kai Bao, Postdoc
- Discovery of biomarkers of periodontal and systemic inflammation
- Women’s health and periodontal disease
- Development of novel in vitro model systems for studying periodontal infections
Swedish Research Council
Periodontology and oral immunology
Periodontal Medicine – periodontal disease investigated pari passu with diabetes mellitus and/or rheumatoid arthritis.
Jeneen Panezai (PhD), Murad Altamash (PhD), Fawad Javed (PhD)
- Professor Anders Larsson, Department of Medical Sciences, Uppsala University, Sweden
- Professor Karl-Gösta Sundqvist, Division of Clinical Immunology, Huddinge, Karolinska Institutet, Sweden
- Professor Björn Klinge, Section of Periodontology, Karolinska Institutet and Department of Periodontology, Malmo University, Sweden
- Professor Mohammad Altamash, AIDM, Karachi, Pakistan
Presence of inflammatory biomarkers in serum in subjects with rheumatoid arthritis, diabetes mellitus and periodontal disease to detect similarities in immune patterns for the three diseases.
Probing pocket depth total index, a disease measurement index that estimate periodontal disease status used in different conditions of systemic diseases.
Periodontal disease influences osteoclastogenic bone markers in subjects with and without rheumatoid arthritis.
Panezai J, Ghaffar A, Altamash M, Engström PE, Larsson A
PLoS ONE 2018 ;13(6):e0197235
Correlation of serum cytokines, chemokines, growth factors and enzymes with periodontal disease parameters.
Panezai J, Ghaffar A, Altamash M, Sundqvist KG, Engström PE, Larsson A
PLoS ONE 2017 ;12(11):e0188945
Periodontal treatment and HbA1c levels in subjects with diabetes mellitus.
Altamash M, Klinge B, Engström PE
J Oral Rehabil 2016 Jan;43(1):31-8
Pre-diabetes and diabetes: Medical risk factors and periodontal conditions.
Altamash M, Arledal S, Klinge B, Engström PE
Acta Odontol. Scand. 2013 Nov;71(6):1625-31
Periodontal conditions, oral Candida albicans and salivary proteins in type 2 diabetic subjects with emphasis on gender.
Javed F, Klingspor L, Sundin U, Altamash M, Klinge B, Engström PE
BMC Oral Health 2009 May;9():12
Self-perceived oral health and salivary proteins in children with type 1 diabetes.
Javed F, Sundin U, Altamash M, Klinge B, Engström PE
J Oral Rehabil 2009 Jan;36(1):39-44
Systemic use of antibiotics in dentistry and its microbiological and clinical effect
Our research focuses mainly on questions on how systemic antibiotics is used in dentistry and its microbiological and clinical effect. (For example the effect of the use of antibiotics in implant dentistry). Our projects are also aimed at gaining knowledge on attitudes and prescription patterns of systemic antibiotics among dentists. Our general hypothesis is that there is a great potential for improvement of antibiotic utilization in odontology although there has been a reduction in antibiotic prescription in dentistry during the last decade. Our projects are designed to attain and develop antimicrobial stewardship in odontology. The project is driven by a large translational group collaborating to cover the identified knowledge gaps within antibiotic utilization in dentistry by combining epidemiological studies and methodology with clinical and basic science. Implementation of the results in the dental society will be aided by active participation in the strategic work to reduce antibiotic usage in dentistry by collaboration with Swedish Public Dental Service (Folktandvården), Institution of dental medicine, Karolinska Institutet, Strama - the Swedish strategic program against antibiotic resistance, The Public Health Agency of Sweden, Swedish Medical Product Agency and other health authorities regarding guidelines and educational efforts.
- Dalia Khalil, assistant professor associated to Karolinska Institutet, Saudi Arabia
- Caroline Grundström, PhD student, Karolinska Institutet, Uppsala läns landsting - Folktandvården
- Bodil Lund, professor, Karolinska Institutet and University of Bergen
- Aron Naimi-Akbar, Karolinska Institutet - Stockholms läns landsting and Karolinska University Hospital
- Björn Klinge, Senior professor Karolinska Institutet
- Sofia Tranaeus, division head, SBU
- George Belibasakis, professor, Karolinska Institutet
- Nagihan Bostanci, professor, Karolinska Institutet
- Andreas Cederlund, assistant professor Stockholms läns landsting - Folktandvården,
- Niko Vähäsarja, PhD student, Karolinska Institutet Stockholms läns landsting/Folktandvården
- Frida Lundgren, Socialstyrelsen
- Morten Enersen, Associate professor, University of Oslo
Prescription of antibiotics in dentistry – a patient register study
Hypothesis: There is a potential for improvement of the utilization of antibiotics in dentistry supported by the unexplained large differences seen between different geographical areas, between private and public dentistry and gender.
Aim: Identify potential areas improvement potential regarding the prescription behavior of antibiotics in dentistry.
Material and methods: Data regarding provided dental care during the period 2009-2017 for adult patients (≥20 years) of age will be collected from the Social Welfare Dental Health Register. Data regarding antibiotic prescriptions from dentistry retrieved at a pharmacy during the same study period will be extracted from the Swedish Drug Register. Prescriptions in close temporal connection to dental treatment will be regarded as associated with the treatment in question. Comparison between time-period before and after publication of recommendations, different geographical regions, gender, type of treatment, private or public care and remaining teeth will be done.
Peri-implantitis – Surgical treatment and risk factors
Dental implant therapy is used worldwide for the rehabilitation of partially and completely edentulous jaws and has shown successful results in a number of studies with survival rates of 90-95% for up to 20 years. However, complications do occur where peri-implantitis is shown to develop in approximately 20% of individuals and 10% of inserted implants. Considering the large number of patients receiving implants, the population developing peri-implantitis is significant.
The general aim of these studies is to assess the surgical treatment and risk factors for treatment of peri-implantitis and to determine clinical and microbiological changes in the oral and intestinal microflora after the use of adjunctive, systemic antibiotics. Within this PhD project, a series of studies are designed.
Prevalence of peri-implantitis in previously bone augmented partially or edentulous areas with special focus on the prevalence of peri-implantitis and the importance of implant maintenance treatment. The aim is also to investigate patients oral health-related quality of life after dental implant treatment with and without autogenous bone grafts.
To evaluate if the use of systemically, adjunctive antibiotics during peri-implant surgery will affect the clinical outcome. The use of two different combinations of antibiotic substances will be evaluated and compared to placebo (A= amoxicillin & metronidazole, B= penicillin V & metronidazole, C= placebo).
To determine the changes in antibiotic susceptibility of oral and intestinal microflora following a 7-day course of systemic antibiotics and to determine the long-term quantitative and qualitative changes in the oral and intestinal microflora following a 7-day course of systemic antibiotics.
To evaluate if the use of systemically, adjunctive antibiotics during peri-implant surgery will affect the long-term clinical outcome (2-3 years of follow up).
Antibiotic utilization in emergency dental care
The aim is to study the use of antibiotic in treatment of patients seeking for emergency dental care, and to determine the most common treatment measures during the emergency visit. A secondary aim is to investigate attitudes and routines towards antibiotic prescription among dentists providing emergency care. This observational questionnaire survey will be conducted at two emergency dental clinics (one public and one private), in Stockholm, Sweden.
Karolinska Institutet - SOF
- Hultin M, Boström L, Gustafsson A. Neutrophil response and microbiological findings around teeth and dental implants. J Periodontol. 1998 Dec;69(12):1413-8.
- Hultin M, Fischer J, Gustafsson A, Kallus T, Klinge B. Factors affecting late fixture loss and marginal bone loss around teeth and dental implants. Clin Implant Dent Relat Res. 2000;2(4):203-8.
- Hultin M, Gustafsson A, Klinge B. Long-term evaluation of osseointegrated dental implants in the treatment of partly edentulous patients. J Clin Periodontol. 2000 Feb;27(2):128-33.
- Hultin M, Gustafsson A, Hallström H, Johansson LA, Ekfeldt A, Klinge B. Microbiological findings and host response in patients with peri-implantitis. Clin Oral Implants Res. 2002 Aug;13(4):349-58.
- Khalil D, Hultin M, Andersson Fred L, Parkbring Olsson N, Lund B. Antibiotic prescription patterns among Swedish dentists working with dental implant surgery:adherence to recommendations. Clin Oral Implants Res. 2014 Apr 15. 10.1111/clr.12402.
- Khalil D, Hultin M, Fredriksson EH, Sjögren E, Lundholm P, Lund B, The use of intra oral radiographic sensors, a possible source of bacterial transmission in the dental office, Journal of Hospital Infection 2016, doi: 10.1016/j.jhin.2016.09.003.
- Khalil D, Hultin M, Rashid MU, Lund B. Oral microflora and selection of resistance after a single dose of amoxicillin. Clin Microbiol Infect. 2016 Aug 26. pii: S1198-743X(16)30328-7. doi:10.1016/j.cmi.2016.08.008.
- Klinge B, Flemming T, Cosyn J, De Bruyn H, Eisner BM, Hultin M, Isidor F, Lang NP, Lund B, Meyle J, Mombelli A, Navarro JM, Pjetursson B, Renvert S, Schliephake H. The patient undergoing implant therapy. Summary and consensus statements. The 4th EAO Consensus Conference 2015. Clin Oral Implants Res. 2015 Sep;26 Suppl 11:64-7. doi: 10.1111/clr.12675.
- Lund B, Hultin M, Tranaeus S, Naimi-Akbar A, Klinge B. Complex systematic review - Perioperative antibiotics in conjunction with dental implant placement. Clin Oral Implants Res. 2015 Sep;26 Suppl 11:1-14. doi: 10.1111/clr.12637.
- Naimi-Akbar A, Hultin M, Klinge A, Klinge B, Tranæus S, Lund B. Antibiotic prophylaxis in orthognathic surgery: A complex systematic review. PLoS One. 2018 Jan 31;13(1):e0191161. doi: 10.1371/journal.pone.0191161.eCollection 2018.
Periodontitis is a chronic inflammatory disease initiated by oral pathogens that activate host immune response and subsequently the production of inflammatory mediators and proteolytic enzymes, collectively contributing to destruction of tooth-supporting structures. This prevalent disease, affecting 38% of adult population, has also been implicated as a risk factor for various systemic diseases such as cardiovascular diseases, diabetes mellitus, obesity, and rheumatoid arthritis.
Despite extensive research and increased knowledge of the pathogenesis of periodontitis, however, the disease is still diagnosed once connective tissue and bone destruction has occurred. One of the challenges for early detection of periodontal disease is its “silent” nature – the disease does not cause pain and progress unnoticed.
Our research aims are to generate the transcriptomic and taxonomic profiling of periodontitis and to identify new targets and diagnostic biomarkers facilitating early and specific diagnosis of the disease, which could lead to identification of individuals at risk of bone loss as well as early treatment preventive strategies.
In addition, we investigate the potential relationship between periodontitis and RA, including the effect of intensive periodontal intervention therapy on disease activity.
Tülay Yucel-Lindberg (Associate professor), Natalija Gerasimcik (Postdoc), Kaja Eriksson (Postdoc, associated), Anna Lundmark (Postdoc, associated), Anna Kats (Postdoc, affiliated group member), Shigufta Syed (Master student), Carina Fie (KI's summer research school). Graduate students: Caroline Lindström, Caroline Åwall Blom, Chhaya Narang and Shahin Rashid.
Previous members of the group that you also want to mention
Tove Båge (PhD), Haleh Davanian (PhD), Zenebech Wondimu (Postdoc), Lin Kiat Lee (Postdoc), Catalin Koro (Postdoc), Gregory Tour (Postdoc) and Pierre Georgsson (Research Assistant)
- To profile the transcriptomic and taxanomic landscape of periodontitis
This project is supported by research grants from Vetenskapsrådet, Patentmedelsfonden and Stockholm County Council, KI/SLL for Odontological Research.
- To identify predictive and diagnostic biomarkers for periodontitis
- To develop anti-inflammatory agents targeting the enzyme prostaglandin E synthases for chronic inflammation/periodontal bone destruction
- To investigate the relationship between periodontitis/periodontal pathogens and the chronic inflammatory disease rheumatoid arthritis
Stockholm County Council, KI/SLL for Odontological Research and Stockholm County Council, ALF – PI,
- To study the interactions between oral microbiome and carcinogenesis
- Swedish Research Council (Vetenskapsrådet) – PI
- Stockholm County Council, KI/SLL for Odontological Research – PI
- Stockholm County Council, ALF – PI
- Patentmedelsfonden – PI
- KID-funding (KI’s faculty funds) – PI
- Vetenskapsrådet /Karolinska Institutet, research school in odontology – PI
- Swedish Research Council (Vetenskapsrådet) – Co-PI
- Seventh Framework Programme, TRIGGER, FP7-HEALTH-2012 - Co-PI
- Ulla och Gustaf af Ugglas stiftelse – PI
- Gene expression profiling of periodontitis-affected gingival tissue by spatial transcriptomics.
Salivary Colony Stimulating Factor-1 and Interleukin-34 in Periodontal Disease.
Martinez GL, Majster M, Bjurshammar N, Johannsen A, Figueredo CM, Boström EA
J. Periodontol. 2017 08;88(8):e140-e149
- Seropositivity combined with smoking is associated with increased prevalence of periodontitis in patients with rheumatoid arthritis.
- Increased citrullination and expression of peptidylarginine deiminases independently of P. gingivalis and A. actinomycetemcomitans in gingival tissue of patients with periodontitis.
- Treponema denticola chymotrypsin-like proteinase may contribute to orodigestive carcinogenesis through immunomodulation.
- Mucin 4 and matrix metalloproteinase 7 as novel salivary biomarkers for periodontitis.
- Effects by periodontitis on pristane-induced arthritis in rats.
- Prevalence of Periodontitis in Patients with Established Rheumatoid Arthritis: A Swedish Population Based Case-Control Study.
- Aminothiazoles inhibit RANKL- and LPS-mediated osteoclastogenesis and PGE2 production in RAW 264.7 cells.
- Transcriptome analysis reveals mucin 4 to be highly associated with periodontitis and identifies pleckstrin as a link to systemic diseases.
- Inhibition of microsomal prostaglandin E synthase-1 by aminothiazoles decreases prostaglandin E2 synthesis in vitro and ameliorates experimental periodontitis in vivo.
- Anna Lundmark - Transcriptomic and taxonomic profiling of periodontitis by massively parallel sequencing
- Kaja Eriksson - Studies on the relationship between periodontitis and rheumatoid arthritis
- Haleh Davanian - Gene expression profiling in periodontitis
- Anna Kats - Expression of prostaglandin E synthase-1 in periodontitis : in vivo and in vitro studies
- Tove Båge - Prostaglandin E synthases in periodontitis-affected gingival tissue and in gingival fibroblasts
My research comprise several areas in Oral health:
· Stress and depression in relation to gingival inflammation/periodontitis
· A new treatment method for peri-implantitis
· Smoking and inflammation
· Oral health among persons with Crohns disease
· Toothbrush with incorporated blue LED light on gingival inflammation
· Oral health among adolescents, adults and elderly
· Systematic reviews
· Dental Hygienist profession
To achieve good oral health is one of the most significant tasks in order to maintain a good quality of life and well-being. My line of research emphasizes this goal and therefore it is very important.
My research include both quantitative, qualitative and pedagogical studies.
Annsofi Johannsen, PhD
Sebastian Malmqvist, RDH, PhD- student, Karolinska Institutet (KI), Anders Gustafsson, DDS, Professor, Specialist Periodontology (KI), Elisabeth Almer Boström, DDS, PhD (KI), Gunnar Johannsen, DDS, Associate professor, Specialist Periodontology, KI, Dana Clinic, Stockholm, George Belibasakis, Professor, Oral microbiology (KI), Talat Qadri, DDS, PhD, Kami Dental AB, Enköping, Nadja Bjurshammar, RDH, PhD (KI) and Jonas Erdenborg RDH (KI)
Anders Liljeborg, Associate Professor, Royal Institute of Technology (KTA), Conny Östman, Professor, Stockholms Universitet, Oana Slusanschi, Assistant Professor, UMF Carol Davila, Bucharest, Marian Cuculescu, Professor, UMF Carol Davila, Bucharest, Atena Galuscan, Professor, UMF "Victor Babes" Timisoara, Henrique Luis, Professor, University of Lisbon, Irene Ebert, DDS, PhD, Swedish Agency for Health Technology Assessment and Assessment of Social Services (SBU), Helena Domeij, DDS, PhD, SBU, Margaret Grindefjord, DDS, PhD, Eastmaninstitutet, Stockholm, Alfheidur Astvaldsdottir, DDS, PhD, The National Board of Health and Welfare, Socialstyrelsen), Peter Lingström, Professor, Institute of Odontology, Sahlgrenska Academy, Gothenburg, Per Ramberg, Associate Professor, Institute of Odontology, Sahlgrenska Academy, Gothenburg, Katarina Konradsson, RHD, PhD, Department of Odontology, Umeå University, Christian Eberhard, PhD, Dentsply Sirona, Germany
The project is about evaluating a new method for the treatment of peri-implantitis. We will use a diode laser with the wavelength of 445nm, in combination with non-surgical infection treatment and compare with surgical treatment. The project includes an in-vitro study with the aim to investigate the effects of laser on e.g. the surface structure of dental implants. Deep interviews will clarify the patients' experiences about these different treatment methods. The research group has a collaboration with Karolinska Trial Alliance and Densply Sirona.
European Training Platform for Continuing Professional Development of Dental Hygienists
The project aim is to harmonize the professional knowledge and skills of dental hygienists in all EU member states, demonstrate the importance of dental hygienists in society, and disseminate knowledge of prevention and treatment of oral diseases. To investigate the oral health among children and adolescents, adults and the elderly through questionnaires in Sweden, Portugal and Romania and also identified the professional skills for dental hygienists in Sweden and in Portugal. Collaboration with the University Carol Davila (Bucharest), Victor Babes (Timisoara) in Romania and University in Lisbon.
The aim is to systematically review and examine the scientific evidence of the efficacy of stabilized stannous fluoride dentifrice in relation to dental calculus, dental plaque, gingivitis, staining, caries, erosions, hypersensitivity and halitosis. Collaboration with the Sahlgrenska Academy and Umeå University
In another ongoing systematic literature dental erosions is studied based on different issues such as diagnosis, treatment and prevention. Collaboration with SBU and Eastman Institute.
Dental Hygienist profession today and a future perspective
The purpose is to identify the stakeholders view of the dental hygienist profession regarding tasks and skills today and from a future perspective. The project will identify important aspects regarding the dental hygienist's competence and the content of dental hygiene education and also the continuing education to be able to meet the future social need. Both a web-based survey and depth interviews with stakeholders will be carried out. Collaboration with co-workers at KI.
- EU/Erasmus+ Project
- The Swedish Research Council
Bjurshammar, N, Malmqvist, S, Johannsen, G, Bostrom, E, Fyrestam, J, Ostman, C. and Johannsen, A. Effects of Adjunctive Daily Blue Light Toothbrushing on Dental Plaque and Gingival Inflammation - A Randomized Controlled Study. (2018) Open Journal of Stomatology, 8, 287-303. DOI: 10.4236/ojst.2018.810027.
Johansson A, Johannsen, G, Uhlin, K. Johannsen A. Dental hygienist students´ learning about motivational interviewing. Dental hygienist students´ learning about motivational interviewing. Dental. Journal 2014, 2(2), 65-77. DOI: 10.3390/dj2020065
This research focus on blue light as an adjunctive method with tooth brushing as a simple way to improve the effect of daily oral care. It is a novel, interdisciplinary approach combining fundamental biomedical research, clinical studies and analytical chemistry. Its overall aim is to investigate the sensitivity of oral microorganisms to phototherapy using blue light, i.e. if these organisms can be eradicated by illumination with visible light without exogenous photosensitizers. The influence on growth/survival of cultivated oral microorganisms is investigated and the impact of irradiation on the chemical porphyrin profile examined by chemical analysis to investigate their role as endogenous photosensitizing agents.
The acquired knowledge is implemented into practical phototherapy treatment in clinical RCT studies where the participating objects themselves use a phototherapy toothbrush for light exposure during ordinary daily oral care. The impact on the study objects oral health status is investigated as well as their perception phototherapy.
The methods used in this research are in-vitro phototherapy treatment of cultivated oral bacteria, chemical analysis of bacterial porphyrins, RCT studies on patients with measurements of oral parameters, and microbiological analysis of bacteria and immunological inflammatory markers. The overall goal is to obtain a scientific basis for the implementation of the concept of phototherapy as a novel tool in everyday oral care. Phototherapy with blue light could be a way to improve oral hygiene by decreasing harmful oral bacteria without the use of antibiotics. In an extension it could decrease the contribution to systemic diseases evolving from infectious diseases in the oral cavity.
Nadja Bjurshammar, RDH, PhD, Lecturer
Annsofi Johannsen, Karolinska Institute
Elisabeth Almer Boström, Karolinska Institute
Gunnar Johannsen, Karolinska Institute
Sebastian Malmqvist, Karolinska Institute
Conny Östman, Professor, Stockholm University, Department of Environmental Science and Analytical Chemistry, Division of Analytical Chemistry and Jonas Fyrestam, PhD, Uppsala University, Department of Chemistry-BMC
Phototherapeutic effects on selected oral bacteria
Aim: To investigate the phototherapeutic effect of illumination by visible blue light on a number of selected bacteria relevant to oral health.
Experimental set-ups are designed for automated LED illumination experiments on agar substrate plates inside a CO2 incubator and Standard Operating Procedures (SOPs) for bacterial cultivation and phototherapy experiments are developed. The methods are applied on Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis. The methods developed in this study will be applied on other important oral bacteria involved in periodontal diseases such as Prevotella intermedia, Fusobacterium nucleatum and Tannerella forsythia. Studies will be performed on human biofilm cultivated in-vitro. The study will give a method for performing in-vitro phototherapy on oral bacteria were the wavelength, light intensity, time of exposure and use of porphyrin precursor are investigated.
Conny Östman, Professor and Jonas Fyrestam, PhD
Stockholm University and Karolinska Institutet.
Killing Escherichia coli with blue light
Aim: To elucidate which of the endogenously produced porphyrins that are most effective in photosensitizing E. coli.
E. coli is cultivated and treated with 405 nm light. Different light doses are applied and the bacterium content of porphyrin is determined. The precursor of porphyrins, 5-aminolaevulinic acid, is used to bypass the negative feedback control of the heme biosynthesis and enhance the porphyrin production in E. coli. The quantum yield of singlet oxygen for three porphyrins commonly detected in E. coli before and after administration of 5-aminolaevulinic acid to the cultivation broth. By adding the porphyrin precursor to E. coli the intracellular concentration of porphyrins increased remarkably and a light dose of 57.6 J/cm2 was sufficient to reduce the number of bacteria with > 5 log10 steps. This shows that E. coli can be killed using their endogenous content of porphyrins, of which the most abundant porphyrin was uroporphyrin. Further studies will be made to elucidate which of the endogenously produced porphyrins are most effective in photosensitizing E. coli.
Conny Östman, Professor and Jonas Fyrestam, PhD
The Swedish Research Council
STHFs stipendium till Professor Sture Nymans minne
McNeil Sweden AB, Tandvårdsstipendium,
TJL Enterprises, Long Beach, CA, USA.
TechLight Systems, Ocala, FL, USA.
- Stella Airila-Månsson, Nadja Bjurshammar, Maha Yakob , Birgitta Söder, Self-reported oral problems, compared with clinical assessment in an epidemiological study, International Journal of Dental Hygiene 5 (2007) 82-86. PMID: 17461959.
- Annsofi Johannsen, Nadja Bjurshammar, Anders Gustafsson, The influence of academic stress on gingival inflammation, International Journal of Dental Hygiene 8 (2010) 22-27. PMID: 20096078.
- Annsofi Johannsen, Klara Bolander-Laksov, Nadja Bjurshammar, Birgitta Nordgren, Cecilia Friden, Maria Hagstromer, Enhancing meaningful learning and self-efficacy through collaboration between dental hygienist and physiotherapist students - a scholarship project, International Journal of Dental Hygiene 10 (2012) 270-276. PMID: 22257302.
- Nadja Bjurshammar, Annsofi Johannsen, Kåre Buhlin, Sofia Tranæus, Conny Östman, On the red fluorescence emission of Aggregatibacter actinomycetemcomitans, Open Journal of Stomatology 2 (2012) 299-306. DOI: 10.4236/ojst.2012.24052
- Jonas Fyrestam, Nadja Bjurshammar, Elin Paulsson, Annsofi Johannsen, Conny Östman, Determination of porphyrins in oral bacteria by liquid chromatography electrospray ionization tandem mass spectrometry, Analytical and Bioanalytical Chemistry 407 (2015) 7013-7023. PMID: 26168965.
- Jonas Fyrestam, Nadja Bjurshammar, Elin Paulsson, Nesrine Mansouri, Annsofi Johannsen, Conny Östman, Influence of culture conditions on porphyrin production in Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis, Photodiagnosis and Photodynamic Therapy 17 (2017) 115–123. PMID: 27825899.
- Gisele Martinez, Mirjam Majster, Nadja Bjurshammar, Annsofi Johannsen, Mrcelo Figueredo, Elisabeth Almer Boström, Salivary Colony Stimulating Factor 1 and Interleukin-34 in Periodontal disease, Journal of Periodontology 88 (2017) 140-149. PMID: 28474967.
- Nadja Bjurshammar, Sebastian Malmqvist, Elisabeth Almer Boström, Jonas Fyrestam, Gunnar Johannsen, Conny Östman, Annsofi Johannsen, The Effects of Adjunctive Daily Blue Light Toothbrushing on Dental Plaque and Gingival Inflammation - A Randomized Controlled Study, Open Journal of Stomatology 8 (2018) 287-303. DOI: 10.4236/ojst.2018.810027