Original study - ZZI 01/2009

Essential oils: antimicrobial effects and potential treatment options in dental implantology

The possibility that the physical lipophilic characteristics of the oils might be the reason for the inhibition of bacterial growth can be ruled out since the lipophilic controls, olive oil and liquid paraffin, did not demonstrate an inhibition zone in any case.

A possible disadvantage is the bitter taste of some concentrated pure oils, though the individual assessment differs. In the literature there are reports of systemic toxicity [16]. There have been isolated reports of contact dermatitis, which can occur with excessive use of undiluted tea tree oil [7] or eucalyptus oil [23]. So far, we have not encountered this in our patients. The proportion of photo-oxidants, which are held responsible for allergizing through the formation of degradation products in the oils, has been reduced in the oils we use by the manufacturer through plant cultivation and the manufacturing process [12, 14]. The situation may be different with synthetic oils or aromatherapy oils and allergizing would be possible. In any case, allergies to classic antiseptics such as povidone iodine are well-known.

The pharmacological composition of natural products varies depending on their origin and conditions of manufacture. This means that different varieties of tea tree oil or eucalyptus oil can have different activities because of different concentrations of active substance. In further studies we found marked differences in antimicrobial effectiveness in the oils from different manufacturers and different countries of origin (results of these studies not shown). We then selected the most effective oils for our applications and mixture. Thus, the results presented here apply primarily for the substances used by us.

We are currently conducting further studies to optimize the form of application of the essential oils for the treatment of peri-implant infections. In initial clinical tests, we have already carried out pocket irrigation. Application in gel form, possibly providing prolonged adhesion to the implant surface, is our current aim.



The tested essential oils exhibit clear antimicrobial effects against staphylococci, streptococci and candida. In particular, the effect on multi-resistant strains should be stressed. The anti-inflammatory properties of essential oils represent an advantage compared to classic antiseptics such as povidone iodine and chlorhexidine. The tested oils are produced naturally and cheaply. If the suspected antimicrobial effects against the dominant strains in peri-implant infections can be confirmed, essential oils may offer an alternative in the local treatment of these infections. This indication will be investigated in further studies.


This study is part of a series conducted in collaboration with Prof. Eugene Sherry, Faculty of Health Sciences and Medicine, Bond University, QLD, AUS, Dr. Sureshan Sivananthan, Dept. of Orthopaedic Surgery, University College of London, UK, and Dr. Paul AJ Russo, Dept. of Immunology, Australian National University, Canberra, AUS. We acknowledge the research grant from the Medical Faculty of Christian Albrecht University in Kiel.


Privatdozent Dr. Dr. Patrick H. Warnke

Klinik für Mund-, Kiefer- und Gesichtschirurgie

Christian-Albrechts-Universität zu Kiel

Arnold-Heller-Str. 16

24105 Kiel

E-Mail: warnke@mkg.uni-kiel.de


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