Research Article Discoloration of Roots Caused by Residual ... of Roots Caused by Residual...

download Research Article Discoloration of Roots Caused by Residual ... of Roots Caused by Residual Endodontic Intracanal Medicaments ... used as short- and medium-term intracanal ... ese irrigants

of 8

  • date post

  • Category


  • view

  • download


Embed Size (px)

Transcript of Research Article Discoloration of Roots Caused by Residual ... of Roots Caused by Residual...

  • Research ArticleDiscoloration of Roots Caused by Residual EndodonticIntracanal Medicaments

    Belinda Kuan-Jung Chen,1 Roy George,1 and Laurence James Walsh2

    1 School of Dentistry and Oral Health, Griffith University, Gold Coast Campus, Southport 4215, Australia2The School of Dentistry, University of Queensland, Brisbane, QLD 4000, Australia

    Correspondence should be addressed to Roy George;

    Received 31 August 2013; Accepted 26 November 2013; Published 9 February 2014

    Academic Editors: S. R. Fidel and G. Plotino

    Copyright 2014 Belinda Kuan-Jung Chen et al. This is an open access article distributed under the Creative CommonsAttribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work isproperly cited.

    Aims. This study examined the extent to which intervisit corticosteroid-based antibiotic pastes (CAP) medicaments contribute tostaining of tooth structure after attempted removal by irrigation techniques. Methods. A total of 140 roots were prepared and thecanalswere filledwith Ledermix paste (demeclocycline),Odontopaste (clindamycin), andDoxypaste (doxycycline).Thepasteswereremoved after 2 or 4 weeks of storage in the dark using EDTA andNaOCl with either a 27-gauge-slotted needle or an EndoActivator(Dentsply).The roots were then exposed to an intense light source for 30minutes eachweek and photographed after a further 1, 3, or6months. Digital images were standardized and data for changes in luminosity were analysed using repeatedmeasures ANOVAanda post hoc test.Results. Removal of themedicament did not prevent later discolouration.Therewas no significant difference betweenthe paste removal methods. Ledermix paste caused the greatest darkening compared to the untreated controls, for both applicationperiods and bothmethods of removal. Doxypaste andOdontopaste caused less darkening than Ledermix.Conclusion.Medicamentsthat stain teethmay continue to discolour teeth despite best attempts to remove them.This study stresses the importance ofmaterialselection and minimising contact of Ledermix within the coronal aspects of teeth.

    1. Introduction

    Corticosteroid-based antibiotic-containing pastes (CAP) areused as short- and medium-term intracanal medicamentsbecause they exert both anti-inflammatory and antibioticactions [111], which are useful in managing periapicalinflammation and root resorption [1, 2, 10, 1218]. Diffusionof triamcinolone and demeclocycline from the CAP productLedermix (Lederle Pharmaceuticals, Wolfratshausen, Ger-many), which contains 1% triamcinolone acetonide and3.21% demeclocycline HCl, through radicular dentine occursreadily, reaching a peak after only two hours [19]. The rate ofrelease of demeclocycline falls to less than one-tenth of theinitial release rate by the 7th day [1, 3, 6, 19, 20].

    Binding of demeclocycline from CAP to dentine and itssubsequent photooxidation when exposed to light can causeintense staining [7, 19, 21]. To address this potential problem,other CAP have been developed, including Odontopaste(Australian Dental Manufacturing, Brisbane, Australia) with

    1% triamcinolone acetonide and 5% clindamycin HCl andDoxypaste (Ozdent, Castle Hill, Australia) with 1% triam-cinolone acetonide and 3% doxycycline hyclate. All threepastes contain the same underlying vehicle of polyethyleneglycol to which various excipients and fillers are added,which do not exert antimicrobial activities. Compared withdemeclocycline, doxycycline is more active as an antibiotic[22, 23] and poses less risk of staining [24]. Past laboratorystudies of root discolouration from use of Ledermix CAPdemonstrated an effect of ambient sunlight [9, 10], but theirradiation parameters could not be controlled rigidly interms of irradiance and fluence. Clinical studies likewisedemonstrate discolouration of replanted avulsed teeth over 12months from Ledermix CAP placed into the root for 6090days [15].

    Recommendations for use of CAP range from two weeksto two months [25]. It is unknown whether existing methodsof removingCAP, such as flushing the root canal systemusing

    Hindawi Publishing Corporatione Scientific World JournalVolume 2014, Article ID 404676, 7 pages

  • 2 The Scientific World Journal

    various irrigants using conventional open-ended needles, areeffective in removing all the material, thereby preventingsubsequent staining of roots. The EndoActivator (DentsplyMaillefer, Ballaigues, Switzerland) is a sonic agitation devicewhich according to supplier has been designed to safely andvigorously energize intracanal irrigants during endodontictreatment. The device employs plastic tips to agitate irrigantsolutions at between 2,000 and 10,000 cycles per second toenhance their cleaning actions [26, 27]. This approach usingmechanical agitation may be preferable to irrigation froma syringe in terms of removing remnants of paste from thecanal.

    This study was undertaken to evaluate and track thedevelopment of root discolouration, after an attemptedremoval of the intervisit corticosteroid-based antibioticpastes (CAP) medicaments using either a conventional irri-gation technique or an EndoActivator.

    2. Materials and Methods

    Extracted single rooted human teeth with finished rootdevelopment and single patent canals and closed apices( = 140) were collected with approval of the institutionalethics committee. The teeth were free of discolouration ortranslucency, fractures, restorations or dental caries affectingthe root surface, or external resorption. After being placedin 1% NaOCl for 20 minutes to degrade external soft tissueremnants, the teeth were rinsed in water and the external rootsurface debrided using an ultrasonic scaler. The majority ofthe crown was removed from each tooth using a diamonddisc to give roots of equal length (12mm). The outer rootsurfaces were treated using aluminium oxide abrasive discsfrom coarse to fine grit to give a standardized matt finish.Roots were then stored in 0.2% thymol solution until used[28]. Working length of teeth was established by passinga size #8K file past the apical foramen and backing offby 1mm. Canals were then prepared to working lengthusing F3 size nickel-titanium rotary ProTaper files (DentsplyInternational), under constant irrigation with alternating 1%NaOCl (Milton) and 15% EDTA/C (Endosure, Dentalife,Croydon, Australia) solutions. A final rinse sequence involv-ing EDTA/C for 2minutes was performed to ensure completeremoval of smear layer. The canals were dried with paperpoints, and the roots stored in sealed containers for 7 days inambient room light. The rationale for storage under ambientlight was to reduce the level of available chlorine from anyremnants of NaOCl without introducing additional reagents[29]. The roots remained moist during this initial one-weekperiod of storage. After recording baseline images, roots wereallocated randomly into 14 subgroups of 10 each (Table 1),and the canals filled completely with the respective CAP(Ledermix, DoxyPaste, Odontopaste) using a 5mL syringewith a small tip placed apically as far as possible undersubdued lighting conditions. Injection of the pastes wascontinued until paste was seen to extrude from the apicalforamen, and then the canal backfilled to the level of the cutsurface. Any excess paste on the cut root surface and at theapical foramen was removed immediately using an alcohol

    wipe. No paste material was allowed to contact the lateralaspects of the roots.The prepared roots containing CAPwerethen kept in complete darkness at 37Cand 100%humidity foreither 2 or 4 weeks. Roots without CAP were run in parallelas negative controls.

    3. Removal of Medicaments

    Canals were rinsed for oneminute each using EDTA and thenNaOCl. These irrigants were delivered in one of two ways.The timing of the interventions was based on manufacturerinstructions for the EndoActivator (Dentsply Maillefer, Bal-laigues, Switzerland) which recommend agitation of fluidsfor 3060 seconds. In both groups, the bulk of the paste wasfirst removed using a hand held ProTaper F3 file introducedin the canal briefly and rotated one-half turn to scrape thewalls lightly. EDTA was then placed into the canal with a27-gauge Monoject open-ended notched needle tip (KendallHealthcare, Mansfield, QLD). In the conventional irrigationgroup, the needle tip was placed 1mm short of the workinglength, and the canal flushed for one minute with EDAduring which time the needle tip was moved manually toobtain gentlemanual agitation and thusmore effectively flushmaterial from the canal.The EDTAwas then flushed out witha syringe and replaced with NaOCl, which was then flushedthrough the canal for a further minute.

    In the secondmethod, after the bulk of the paste had beenremoved using the hand held ProTaper file, EDTAwas placedinto the canal with a syringe, and the solution agitated for oneminute using an EndoActivator (Dentsply Maillefer) fittedwith an ISO 25 size disposable plastic tip.The EDTAwas thenflushed out with a syringe and replaced with NaOCl, whichwas agitated with the EndoActivator for a further minute,using the same tip. After removal of CAP, all canals werethen dried with paper points before proceeding to the lightexposure phase of the study.

    4. Light Exposure

    Roots were subjected to irradiation for 30 minutes once perweek over the following 6 months using a 35 Watt XenonHID spotlight which served as an artificial sunlight sourcereplicating ground level sunlight (colour temperature 6000Kelvin) [30]. This light was used at a 40 cm target distance,giving an intensity of 29.4 million mean spherical candelasand a flux of 3300 lumens. The spectral distribution ofthe light source was analysed with a spectrometer (ModelUSB2000, Ocean Optics, Dunedin, FL, USA). Samples werestored in the dark at 37C and 100% humidity bet