Oral diseases

Oral microbiology and infection

Principal investigator: Georgios Belibasakis

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.

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.

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, in which Karolinska Institutet is a partner.

Mapping of the oral resistome

This theme aims to investigate the presence of antibiotic resistances among microorganisms involved in oral infections that may imperil the outcome of antibiotic treatment. The project is founded on a cooperation with clinical and laboratory hubs at the Karolinska University Hospital and Karolinska University Laboratory, respectively. It is based on complementary retrospective and prospective approaches that screen for antibiotic resistances in the available registry data and in newly collected oral infection samples, respectively. In the latter approach, both conventional susceptibility testing and molecular detection of resistance genes are performed. Deeper molecular characterization of known and unknown resistance genes is acquired by whole genome sequencing. This continuous data collection will deliver a dynamic mapping of the ‘oral resistome’ to assist in the development of strategies and guidelines for antibiotic stewardship programs.

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

Group members

Angelika Silbereisen, Postdoc

Kai Bao, Postdoc

Projects

• 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

Research support

• Swedish Research Council
• Karolinska Institutet
• SOF

Oral health in patients with memory disorders

Principal Investigator

Kåre Buhlin, Associate Professor, Division of Oral Diseases

The main objective is to investigate if periodontal disease and memory-related diseases, particularly Alzheimer´s disease (AD), are associated. If a causal relation is found between dental infections and memory-related diseases it could have important clinical implications in the prevention of AD. The overall objective is to clarify whether oral inflammatory diseases can be related to the brain's memory capacity.

Methods: Three groups of patients with distinctive dementia diagnoses and matched controls will undergo a dental examination, including saliva and bacterial samples and radiological examination. Patients and controls will fill out a questionnaire that highlights their attitude to dental care, dental health, public health and socio-economic parameters. The controls will undergo Mini Mental State Examination. Analysis of plasma, saliva and cerebrospinal fluid (CSF) will be performed and the results will be correlated with dental status.

If a causal relationship between periodontal disease and memory-related diseases can be identified, it will open new possibilities for preventing disease in this vulnerable and frail patient group.

Project: Clinical, microbiological and immunological efficacy of antiseptics in the management of chronic periodontitis

To investigate polyhexamethylene guanidine phosphate antimicrobial activity and evaluate it in comparison to chlorhexidine and water. Evaluate it as a chair side rinse

Group members

• Anton Vitt, PhD student, Division of Periodontology and Implant Dentistry
• Jacob Holmer, PhD student, Division of Periodontology and Implant Dentistry

Collaborations

• The Geriatric Clinic, Karolinska University Hospital, Huddinge, Sweden
• Belarusian State Medical University, Minsk, Belarus

Financing

The Swedish Dental Society, CSTP grant, KI, SOF grant, Stockholm County Council, KIRT grant, KI

Systemic use of antibiotics in dentistry

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.

Group Members

• Dalia Khalil, assistant professor associated to Karolinska Institutet, Saudi Arabia
• Caroline Grundström, PhD student, Karolinska Institutet, Uppsala läns landsting - Folktandvården

Collaborators

• 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,
• Eastman
• Niko Vähäsarja, PhD student, Karolinska Institutet Stockholms läns landsting/Folktandvården
• Frida Lundgren, Socialstyrelsen
• Morten Enersen, Associate professor, University of Oslo
• STRAMA
• Folkhälsomyndigheten

Projects

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.

Research support

Karolinska Institutet - SOF

Articles

• 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.

Oral Health

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.

Group members

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 and Jonas Erdenborg RDH (KI)

Collaborations

Anders Liljeborg, Associate Professor, Royal Institute of Technology (KTA).

Projects

Peri-implantits

The project compare treatment of peri-implantitis with either 970 nm laser or conventional mucosal flap surgery, to measure clinical parameters, inflammatory and microbial response. 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. We will also compare the immune cell profile in peri-implantitis with the immune cell profile in periodontitis and health lesions.

Theory-based behavioural interventions – A pedagogic and patient centered project

Comprehensive dental care should include effective, evidence-based behavioural methods (such as qualified counselling and/or theory-based counselling) for the patient education, intended to achieve long-term lifestyle changes and behaviours or importance to oral health. The overall aim is to explore the existing teaching regarding the use of behavioural intervention methods, identify and obstacles and design a separate syllabus within this topic, to achieve better oral health and quality of life among the patients. To identify prerequisites and limitations for using theory-based behavioural interventions among the dental hygienist by questionnaires and in-depth interviews. And explore the patients’ perspectives regarding these methods to see if it can affect oral health and quality of life.

Collaborations

Nikolaos Christidis, DDS, Associate professor, Division of Oral Rehabilitation, Karolinska Institutet, Terese Stenfors, Professor, Department of Learning, Informatics, Management and Ethics, Karolinska Institutet, Henrique Luis, Professor, University of Lisbon.

Systematic reviews

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.

Research support

• SOF/SLL
• EU/Erasmus+ Project
• The Swedish Research Council

Articles

Effects of Adjunctive Daily Blue Light Toothbrushing on Dental Plaque and Gingival Inflammation - A Randomized Controlled Study. (2018)
Bjurshammar, N, Malmqvist, S, Johannsen, G, Bostrom, E, Fyrestam, J, Ostman, C. and Johannsen, A. 
Open Journal of Stomatology, 8, 287-303 DOI: 10.4236/ojst.2018.810027.

Dental patients' perceptions and motivation in smoking cessation activities. DOI: 10.4236/ojst.2018.810027.
Andersson P, Johannsen A
Acta Odontol. Scand. 2016 ;74(4):285-90

Consumption of dental treatment in patients with inflammatory bowel disease, a register study.
Johannsen A, Fored MC, Håkansson J, Ekbom A, Gustafsson A
PLoS ONE 2015 ;10(8):e0134001

Smoking and inflammation: evidence for a synergistic role in chronic disease.
Johannsen A, Susin C, Gustafsson A
Periodontol. 2000 2014 Feb;64(1):111-26

The importance of measuring toothpaste abrasivity in both a quantitative and qualitative way.
Johannsen G, Tellefsen G, Johannsen A, Liljeborg A
Acta Odontol. Scand. ;71(3-4):508-17

Dental hygienist students´learning about motivational interviewing. Dental hygienist students´ learning about motivational interviewing
Johansson A, Johannsen, G, Uhlin, K. Johannsen A
Dental. Journal 2014, 2(2), 65-77. DOI: 10.3390/dj2020065

Dental implants from the patients perspective: transition from tooth loss, through amputation to implants - negative and positive trajectories.
Johannsen A, Westergren A, Johannsen G
J. Clin. Periodontol. 2012 Jul;39(7):681-7

Gingival inflammation, increased periodontal pocket depth and elevated interleukin-6 in gingival crevicular fluid of depressed women on long-term sick leave.
Johannsen A, Rydmark I, Söder B, Asberg M
J. Periodont. Res. 2007 Dec;42(6):546-52

Perception of the Professional Role, and Competence of Swedish Dental Hygienists: A Questionnaire and Interview Study.
Erdenborg J, Malmqvist S, Bjurshammar N, Johannsen G, Hultin M, Johannsen A. Stakeholder J
Int Soc Prev Community Dent. 2020 Jan 24;10(1):54-61.

The Dental Hygienists in Sweden and Portugal: A Comparative Study.
Johannsen A, Malmqvist S, Graça S, Assunção V, Albuquerque T, Luis H.J
Int Soc Prev Community Dent. 2019 May-Jun;9(3):296-302.

Effects of stabilized stannous fluoride dentifrice on dental calculus, dental plaque, gingivitis, halitosis and stain: A systematic review.
Johannsen A, Emilson CG, Johannsen G, Konradsson K, Lingström P, Ramberg P.
Heliyon. 2019 Dec 9;5(12):e02850.

A pilot study on the effectiveness of a 2-year school-based oral health educational programme using experiential learning among adolescents.
Sfeatcu R, Dumitrache MA, Cărămidă M, Johannsen A, Perlea P.
Int J Dent Hyg. 2019 Aug;17(3):221-228.