Root canal filling evaluation using optical coherence tomography Meda L.Negrutiu a , Cosmin Sinescu a , Michael Hughes b , Adrian Bradu b , Carmen Todea c , Cosmin I.Balabuc c , Laura M.Filip c and Adrian Gh. Podoleanu b a Department of Prostheses Technology and Dental Materials, Faculty of Dental Medicine, University of Medicine and Pharmacy "Victor Babeş" Timişoara, Romania b Applied Optics Group, School of Physical Sciences, University of Kent, Canterbury, UK c Department of Oral Rehabilitation, Faculty of Dental Medicine, University of Medicine and Pharmacy "Victor Babeş" Timişoara, Romania ABSTRACT The root canal fillings are destined to seal the root canal especially in the apical areea. Invasive techniques are known which are used to assess the quality of the seal. These lead to the destruction of the probes and often no conclusion could be drawn in respect to the existence of any microleakage in the investigated areas of interest. Optical coherence tomography (OCT) is a relatively novel non-invasive imaging technique which presents potential in assessing the microleakage of the apical area in the root canal fillings with micron depth resolution. 3D reconstruction allows a complete view with obvious display of gaps in the apical root canal filling. For this study, 30 monoradicular teeth were prepared by conventional and rotative methods. Afterwards, root canal fillings were produced in each tooth. The images obtained show some microleakage in all the investigated root canal fillings. The advantages of the OCT method consist in non-invasiveness and high resolution. Keywords: root canal filling evaluation, microleakage, root apical level, optical coherence tomography 1. INTRODUCTION Successful root canal treatment is based on diagnosis, treatment planning, knowledge of tooth anatomy, and traditional concepts of debridement, sterilization, and obturation. Adequate access and a straight-line path to the canal system allow complete irrigation, shaping, cleaning and quality obturation. Root canal treatment can be predictably successful with careful cleaning and shaping of the canal system, three- dimensional obturation, and a well-fitting coronal restoration. Regardless of the obturation method, emphasis has to be placed on the process of cleaning and shaping of the root canal, without which obturation cannot be effective. Endodontic therapy consists in cleaning and shaping the root canal system, removing organic debris and sealing the intra-canal space with permanent filling materials. During the cleaning and shaping process, organic and inorganic debris accumulate on the canal wall, producing an amorphous, irregular smear layer, which may interfere with the adhesion and penetration into dentinal tubules of intra- canal medicament or root canal sealer during obturation. Prior to obturation, the smear layer has to be removed to allow good adhesion of the sealer, as well as the dentin interface has to be thoroughly dried. The obturation must seal the pulp space both apically and laterally, thus preventing further apical irritation from either incomplete elimination of bacteria and their products or communication between apical tissues and oral cavity. Biophotonics: Photonic Solutions for Better Health Care, edited by Jürgen Popp, Wolfgang Drexler, Valery V. Tuchin, Dennis L. Matthews, Proc. of SPIE Vol. 6991, 69911T, (2008) · 1605-7422/08/$18 · doi: 10.1117/12.780901 Proc. of SPIE Vol. 6991 69911T-1 2008 SPIE Digital Library -- Subscriber Archive Copy