on root filling quality in general dental practice...european journal of dental education 19 (2015):...

Onroot-fillingqualityingeneraldentalpractice

LisbethDahlström

DepartmentofEndodontologyInstituteofOdontology

SahlgrenskaAcademyatUniversityofGothenburg

Gothenburg2016

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Onroot-fillingqualityingeneraldentalpractice©LisbethDahlströ[email protected](printed)ISBN978-91-628-9681-2(e-publ)http://hdl.handle.net/2077/41240PrintedinGothenburg,Sweden2016PrintedbyIneko,AB,Gothenburg

“A moment’s insight is sometimes worth a lifetime’s experience”

Oliver Wendell Holmes, Sr

Tomyfamily

On root-filling quality in general dental practice LisbethDahlström

DepartmentofEndodontology,InstituteofOdontologySahlgrenskaAcademyatUniversityofGothenburg,Göteborg,Sweden

ABSTRACT

In Sweden, 250,000 root fillings are performed every year. The outcome of root canaltreatment (RCT) is strongly correlated to the technical quality of the root filling.Epidemiological studies show high frequencies of suboptimal technical quality.Withinthe Swedish population, there are about 2,500,000 root-filled teeth with persistentperiapical infections. There is therefore a discrepancy between the results that can beachieved and what is actually achieved in general dentistry. RCT is technicallycomplicated, but new technology for instrumentation appears to have facilitated theprocedure, as well as the technical results. Study I is a long-term follow-up of animplementation programme in the Gothenburg Public Dental Health Service (DHS),whereallthedentistswereeducatedinthenewtechnology.Theinitialimprovementinroot-filling quality as seen in the radiographs remained. However, poor quality rootfillings were still performed. In Study II, a different educational approach wasinvestigatedamongallthedentistsintheSödraÄlvsborgDHS.Theaimsweretoactivatelocal networks at the clinics and enable the hands-on training to be performed by aneducated dentist from each clinic. The results corresponded to the results in theGothenburgstudy.Mostdentistsadoptedthenewtechniqueandthefrequencyofgoodquality root fillings improved, albeitwithout any concomitantdecrease inpoorqualitycases.Itseemsobviousthatdentistsfairlyfrequentlyacceptinadequatetechnicalresults.With a view to understanding the reasons and decision-making related to suboptimaltreatment, Studies III and IV used focus-group discussions with dentists within theGothenburgDHS.Beforetheinterviews,thedentistsassessedtheroot-fillingqualityinanumberofcases.The threecasescausing themostdivergentopinionswerechosen forfurtherdiscussionsinthefocusgroups.Seveninterviewswerevideotaped,transcribedand analysed using qualitative content analysis. In Study III, the attitude to RCT washighlighted.Thetreatmentwasoftenassociatedwithnegativefeelings,suchasstressandfrustration. The treatments were perceived as complex and technically difficult, oftenperformedwithafeelingoflossofcontrol.Mostdentistsstatedthattheywerenotabletocompleteacasewithintheallottedtime.Often“goodenough”wasseenasarealisticgoalinsteadofoptimalquality.Theideaof“goodenough”wasfurtherexploredinStudyIV.Theanalysisshowedthattheradiographicimagewasnotasufficientbasisforwhetherornottoacceptapoorrootfilling.Instead,itwasalwaysthespecificsituationinwhichthe root fillingwasmade thatwasdecisive. These situationswere related topulpal orperiapicalhealth,riskassessmentsorpersonaloreconomicresources.

Keywords:root-filling,nickel-titaniumrotaryinstrumentation,implementation,hands-on,socialnetwork,focusgroups,qualitativecontentanalysis,generaldentalpractitioners,stress

ISBN:978-91-628-9680-5(printed)ISBN:978-91-628-9681-2(e-publ)http://hdl.handle.net/2077/41240

SAMMANFATTNING PÅ SVENSKA ISverigerotfyllsungefär250000tänderårligen.Behandlingsutfalletärstarktkorrelerattill den tekniska kvaliteten på rotfyllningen. Epidemiologiska röntgenologiska studier isvenskaoch internationellapopulationerpekarsamfälltpåenhög frekvensav teknisktbristfälliga rotfyllningar.Det beräknas finnas2500000 rotfyllda tänder i Sverigemedtecken på apikal inflammation. Rotfyllningar utförda av specialister visar en betydligthögreandelavgodkvalitetochinvändningsfriaapikalaförhållanden.Detföreliggeralltsåenstordifferensmellandenkvalitetsomärmöjligattnåochdensomfaktisktuppnåsavtandläkare i allmänpraktik. Rotbehandlingar är tekniskt komplicerade men nyateknologiskahjälpmedelattinstrumenterakanalertyckskunnaförenklaprocedurenochgemöjlighetertillförbättradrotfyllningskvalitet.StudieIärenlångtidsuppföljningaveninsats där alla allmäntandläkare i Göteborgs Folktandvård utbildades i ett nyttinstrumenteringssystem.Man fann att den initialt allmänt förbättrade röntgenologiskarotfyllningskvalitetenstodsigövertid.Emellertidproduceradesfortfaranderotfyllningarav bristande kvalitet. Ett annorlunda pedagogiskt upplägg prövades i en utbildning avsamtliga tandläkare i Södra Älvsborgs Folktandvård (Studie II). Syftet var att aktiverakliniken som ett lokalt nätverk och utbildningens praktiska del drevs av en lokaltandläkare. Man fick motsvarande resultat som i Göteborgsstudien. En stor del avtandläkarna gick över till ny teknik och rotfyllningskvaliteten förbättrades i stort.Återigen kvarstod dock noterbart många rotfyllningar av bristande kvalitet. Det tycksalltså uppenbart att tandläkare relativt frekvent accepterar ett suboptimaltbehandlingsresultat. I syfte att kunna fånga detaljer i resonemang och beslutsfattandebakom ett sådant accepterande planerades studie III och IV som fokusgruppintervjuermed tandläkare i Folktandvården i Göteborg. Före varje intervju fick tandläkarnabedöma rotfyllningskvaliteten på ett antal utskickade fall. Tre av dessa tjänade sedansomutgångspunktfördiskussionerna.Sju intervjuervideofilmadesochtranskriberadesochtextmaterialetanalyseradesmedhjälpavkvalitativinnehållsanalys.Totaltdeltog33tandläkare i fokusgrupperna. I studie III lyfts tandläkarnas allmänna inställning tillrotbehandling. Analysen visade att behandlingarna ofta var förknippade med en radnegativakänslorsomstress,frustrationochmentalutmattning.Deupplevdesocksåoftasomkomplexaochteknisktsvåra,mångagångergenomfördamedenuppenbarkänslaavatt sakna kontroll. Ofta antyddes att ”bra nog” var ett mer realistiskt mål än optimalkvalitet. Idén om ”bra nog” analyserades vidare i studie IV. Analysen visade atttandläkarnainteenbarttoghänsyntillrotfyllningenstekniskakvalitet,utandettycktesalltid vara specifika situationer i det enskilda fallet som avgjorde om en rotfyllningaccepteradesellerinte.Typiskasådanasituationerbefannsvararelateradeantingentilldetsjukdomstillståndsombehandlades,deriskersomvarvärdaatttaellerderesursersomvarrimligaattförbruka.

Konklusion: Nya teknologiska innovationer ger möjligheter att förbättrarotfyllningskvaliteten i allmänpraktik. Problemetmed suboptimal behandling kandockinte förväntas att försvinna. Att dålig teknisk kvalitet accepteras av tandläkare berordelvis på att rotbehandlingar ofta genomförs under hög stressnivå och upplevs somkomplexa och tekniskt svåra. För att hantera den kliniska situationen måste enuppfattningom”branog”utvecklas.Ensådanuppfattningtycksintefinnassomenfärdigmatris, applicerbar på enskilda fall. Snarare tycks specifika kontextuella drag i detenskilda fallet vara det som avgör om kvaliteten på en rotfyllning ska betraktas somacceptabelellerinte.

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CONTENTS ........................................................................................... II

ABBREVIATIONS ............................................................................................. IIITHE LAYOUT OF THE THESIS ........................................................................... IV1 INTRODUCTION ........................................................................................... 12 AIMS ........................................................................................................... 5

3.1 Studies I and II ...................................................................................... 73.2 Studies III and IV ................................................................................ 133.3 Main findings ...................................................................................... 223.4 Ethical considerations .......................................................................... 23 4.1 Studies I and II: Quantitative methods ................................................ 244.2 Studies III and IV: Qualitative methods .............................................. 26

5 GENERAL DISCUSSION .............................................................................. 295.1 Root-filling quality and apical periodontitis ........................................ 295.2 Adoption pattern and poor performance .............................................. 315.3 Factors that might obstruct professional development ........................ 325.4 Success in endodontics ........................................................................ 35

6 CONCLUSIONS .......................................................................................... 377 FUTURE PERSPECTIVES ............................................................................. 38ACKNOWLEDGEMENTS .................................................................................. 40REFERENCES .................................................................................................. 42APPENDIX ....................................................................................................... 53

LIST OF PAPERS .....

3 ....................................... 6PARTICIPANTS METHODS AND RESULTS, ............

4 METHODOLOGICAL CONSIDERATIONS ...................................................... 24

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LIST OF PAPERS This thesis is based on the following studies, referred to in the text by theirRomannumerals.

I. DahlströmL,MolanderA,ReitCIntroducingnickel-titaniumrotaryinstrumentationinapublicdentalservice:Thelong-termeffectonrootfillingqualityOralSurgOralMedOralPatholOralRadiolEndod(2011);112:814-819

II. DahlströmL,MolanderA,ReitCTheimpactofacontinuingeducationprogrammeonadoptionofnickel-titaniumrotaryinstrumentationandroot-fillingqualityamongstagroupofSwedishgeneraldentalpractitionersEuropeanJournalofDentalEducation19(2015):23-30

III. DahlströmL,LindwallO,RystedtH,ReitC“Workinginthedark”:SwedishgeneraldentalpractitionersonthecomplexityofrootcanaltreatmentInmanuscript

IV. DahlströmL,LindwallO,RystedtH,ReitC“It´sgoodenough”:Swedishgeneralpractitionersonreasonsforacceptingsub-standardroot-fillingqualityInmanuscript

PapersIandIIareprintedwiththepermissionofthepublishers.

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ABBREVIATIONS

AP ApicalPeriodontitis

DHS DentalHealthService

GDP GeneralDentalPractitioner

NiTi

NTRI

RCT

Nickel-Titanium

Nickel-TitaniumRotaryInstrumentation

RootCanalTreatment

iv

THE LAYOUT OF THE THESIS

Lisbeth Dahlström

1

1 INTRODUCTION

Root canal treatment (RCT) can be regarded as a set of procedures designedeither to prevent or to cure apical periodontitis (Ørstavik & Pitt Ford 2008).The technical quality of the treatment as reflected in the radiographicappearance of the root filling has been found strongly to correlate to thetreatment outcome in terms of the presence or absence of signs of apicalperiodontitis. Radiographic epidemiological surveys unanimously report highrates of substandard treatments and accordingly find high rates of apicalperiodontitis inroot-filled teeth. InSweden,asmallcountrywitheightmillioninhabitantsovertheageof15years,approximately250,000teetharerootfilledonanannualbasis,correspondingroughlytoaneconomiccostof1billionSEK(Försäkringskassan 2013, Statistics Sweden 2014). The number of root-filledteeth with signs of apical periodontitis in the Swedish population can beestimatedtoamounttoatleast2,500,000.

Apicalperiodontitis

Whenthepulpisdeprivedofitsvitality,itsdefensivecapabilityislostand,ifleftun-negotiated,thepulpalspacewillbeinvaded,overtime,bymicro-organisms(Bergenholtz 1974, Sundqvist 1976). Bacteria, bacterial products andinflammatorymediators accumulate in the root canal system andmay spreadbeyondtheapicalforaminaandelicitaninflammatoryreactionintheperiapicaltissues:apicalperiodontitis(AP).Apicalperiodontitisfunctionsasanimportantprotectivebarriertopreventthespreadofbacteriaandbacterialcomponentstootherbodycompartments(Metzgeretal.2010).Inspiteofitsbarrierfunction,AP may occasionally be associated with local clinical symptoms such astenderness, pain and swelling and, albeit rarely, it may be a life-threateningcondition if it spreads throughanatomicalpathwaysor the circulatory system(Skaug&Bakken2010).

ReasonsforperformingRCT

ThereareseveralpossiblewaysforthepulptobecomecompromisedandriskdevelopingpulpitisandsubsequentpulpalnecrosisandAP.Injuriestothepulpmaybearesultofcaries, trauma,dentinalcracksorrestorativeprocedures. Inothercases,APmaybeiatrogenicallyinduced,forexample,ifasepticconditionsarenotmaintainedduringtreatmentorifinfectedmaterialisextrudedthrough

On root-filling quality in general dental practice

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the apical foramen during endodontic treatment (Yusuf 1982, Happonen &Bergenholtz2003).Sometimes,clinicallyhealthypulpsaretreated.Mostoften,the purpose of this treatment is to enable the anchoring of a prostheticabutmentwhenthemajorpartofatoothcrownislost.

Caries is regarded as the main reason for pulpal injury. During the last fewdecades, a substantial decline in caries prevalence has been documented inmanyindustrialisedcountries(Marthaler2004).However,despitethefactthatgeneraldentalhealthhasimproved,thefrequencyofperformedrootfillingshasnotdecreased.Instead,reportsbasedondatacoveringaperiodof20-30yearsshow an increase in the numbers of root fillings (Bjørndal & Reit 2004,Eckerbom2007).Thiscanbeexplainedinpartbyareductioninthefrequencyof extracted teeth, exposing more anatomically complicated teeth such asmolarstotheriskofpulpaldisease(Bjørndal&Reit2004).

Root-fillingquality

NumerousstudieshavedemonstratedanassociationbetweenthequalityoftherootfillingandAP,inthatinadequaterootfillings(tooshortortoolongand/ordefectiveseal)increasethefrequencyofAP(Bergenholtzetal.1973,Peterssonet al. 1986, Eckerbom etal. 1989, De Cleen et al. 1993, Saunders et al. 1997,Kirkevang et al. 2000, Segura-Egea et al. 2004, Ridell et al. 2006, Frisk et al.2008). In relation to the length of the root filling, the best outcome has beenreported when the obturation ends within the apical 2 mm from theradiographicapex(Bergenholtzetal.1973,Sjögrenetal.1990,Frisketal.2008,Ngetal.2011,Ricuccietal.2011).Iftherootfillingistooshort,thereisariskthatinfectedpulpremnantsandinfecteddentinechipswillbeleftintheapicalpart of the canal. Over-instrumentation may induce displacement of infecteddentinchipsintotheperiapicaltissues(Yusuf1982).Over-instrumentationwillalsoresultinthewideningoftheconstrictionandtheapicalforamen,whichinturnmakesitmoredifficulttocreateadensesealinthatarea.Adefectiveseal,especially in the apical part of the canal, provides space for survivingmicro-organismsandallowstissuefluidintothecanalfortheirnutritionandgrowth.

Technicaldevelopment

Traditionally, stainless steel files have been used to negotiate the root canal.However, in curved canals, these files have been shown to create variousproceduralerrors.Thegenesisoftheseerrorsisfoundinthecharacteristicsofthe stainless steel alloy. It is a stiff alloy and there is a substantial increase ininstrument stiffness with increasing instrument size. In order to reduce theprocedural errors, manufacturers have tried to alleviate the problems by

Lisbeth Dahlström

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altering the tip design of the files, changing the cutting surface and makingalterations to the composition of the material. However, one of the mostsignificant advances in order to overcome the difficulties caused by curvedcanalswastheintroductionofnickel-titaniumalloytofabricaterootcanalhandfiles. For this, Walia et al. (1988) used Nitinol, a nickel-titanium (NiTi)orthodonticwire thatwasmachineddirectly on the starting blanks. The alloyhas super-elastic capacity,meaning that the alloy returns to its original shapeuponheavyloading.Laboratorystudies(Esposito&Cunningham1995,Bishop&Dummer1997),aswellasaclinicalprospectivecross-overstudy(Pettietteetal.1999),havedemonstratedthatNiTihandfilesmaintaintheoriginalshapeofthecanalmoreeffectivelythanstainlesssteelhandfiles.

In the early-1990s, nickel-titanium rotary instrumentation systems (NTRI),hand-piece driven instruments at low speed, were developed. The NTRItechnique was reported to facilitate root canal treatment and generate goodroot canal geometry in laboratory tests (Esposito & Cunningham 1995,Baumann&Roth1999,Gluskinetal.2001,Schäfer2001,Hülsmannetal.2003,Schäfer&Florek2003,Guelzowetal.2005). Inaretrospectivestudyofcasestreatedbyundergraduateandpostgraduatestudents,lowerratesofproceduralerrorssuchasledgesandperforationswerereportedforNTRIincomparisontostainless steel hand files (Cheung& Liu 2009). In order to compare the root-canal-shaping ability of manual NiTi files and NTRI, Sonntag et al. (2003)performed a laboratory study among undergraduate dental students. Theresults indicated that NTRI exhibits advantages over themanual technique inthe hands of novice users. Procedural errors occurred less frequently, theworkinglengthwasmoreoftenachievedandlesstimewasrequiredtopreparethe canals. However, in the hands of two experienced dentists, no suchdifferenceswereregistered(Petersetal.2001).

Clinicalvs.epidemiologicalstudiesrelatedtooutcome

High quality RCT requires meticulous accuracy. In order to optimise thedisinfection of the canal andminimise the risk of bacterial contamination, allconditionshavetobecontrolledduringtheentiretreatment.Sundqvist&Figdor(1998)summarisedtherequirementsasfollows.

“It is important thateachphaseof theendodontic treatment isperformedaccording to accepted clinical standards: aseptic working conditions,adequate disinfection, precise canal length measurement, adequate canalpreparation, irrigation, complete root canal obturation and a seal-tightcoronalrestoration.“


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These idealconditionsmaybepresent inclinicallycontrolledstudies inwhichstrict protocols are followed and “success rates” of 85% to 95% have beenreported (Strindberg 1956, Kerekes & Tronstad 1979, Sjögren et al. 1990,Ørstavik1996,Molvenetal.2002,Gesietal.2006).However,bothScandinavianand international epidemiological population studies, representing treatmentsperformedby general dentists, provide a different picture. They reveal a highfrequency of inadequate root fillings and it is not possible to determine theextent to which treatment protocols have been followed. Since the quality ofRCTlargelydeterminestheperiapicalstatus,aconsiderablyhigherfrequencyofAP is tobeexpected.Consequently,at teethroot filledbygeneraldentists, thelevelofapicalconditionstowhichnoobjectionscouldberaised,isreportedtoreach only 35-75% (Ödesjö et al. 1990, Weiger et al. 1997, Kirkevang et al.2001a; Lupi-Pegurier et al. 2002, Jimenez-Pinzon et al. 2004, Kabak&Abbott2005,Siqueiraetal.2005,Sunayetal.2007,Frisketal.2008,Georgopoulouetal.2008).Inanepidemiologicalstudy,theradiographicevidenceofarootfillinghas been shown to be the most important risk indicator for having AP(Kirkevang&Wenzel2003).

Lisbeth Dahlström

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2 AIMS

The starting point of this thesis is the clear distinction between what it ispossible to achieve (as reflected in clinically controlled studies) and what isactuallyachieved(asreflectedinepidemiologicalstudies)withRCTintermsoftreatment outcome. Since treatment outcome is strongly correlated to thetechnical quality of the root filling and poor quality seals are prevalent ingeneral dentistry, possiblemeans of improvementwere the focal point in thepresented studies. Two research strategies were chosen: one action oriented(effects of implementing new instrumentation technology) and one exploringreasoning and understanding related to RCT among general dentalpractitioners.

Thespecificaimswereto:

I. Studythelong-termeffectonroot-fillingqualityofaneducationprogrammeintroducingNTRIinapublicdentalhealthorganisation

II. Testthehypothesisthatamodifiededucationprogrammeaimingattheactivationofsocial/professionalnetworkswouldincreasetheadoptionrateofNTRIandimproveroot-fillingquality

III. ExploreelementsofreasoningandunderstandingthatmightobstructtheperformanceofgoodqualityRCTandmakegeneraldentalpractitionersproduceandacceptrootfillingsofsubstandardquality

IV. Exploretheconceptof”goodenough”treatmentresultsbyanalysingreasonsandargumentsinfavouroftheacceptanceorrejectionofsubstandardroot-fillingqualityasreportedbygeneraldentalpractitioners


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3 PARTICIPANTS, METHODS AND RESULTS

STUDY I II III IV

Method Quantitative Quantitative Qualitative Qualitative

Design Follow-up Educationalintervention

Descriptive,exploratory

Descriptive,exploratory

Data QuestionnaireRadiographs

QuestionnaireRadiographs

Focus-groupinterviews

Focus-groupinterviews

Sample Publicdentalhealth

practitionersinGothenburg

Publicdentalhealth

practitionersinSödraÄlvsborg

Publicdentalhealth


Publicdentalhealth


Analysis Radiographic&statisticalanalyses

Radiographic&statisticalanalyses

Qualitativecontentanalysis

Qualitativecontentanalysis

Included(n)

AllPDHdentists

120(2001)174(2005)

AllPDHdentists

90

33

33

Gender,female(%)

69

70

70

70

Meanyearsofage

Unknown

Unknown

44

44

Meanyearsofpractice

19

17

15

15

Lisbeth Dahlström

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3.1 Studies I and II

Background

ThereplacementofstainlesssteelinstrumentswithmoreflexibleNiTifileswasshown in laboratory tests to facilitate canal preparation and result in anincreasedfrequencyofgoodqualityrootfillings(Esposito&Cunningham1995,Bishop&Dummer1997).FurtherimprovementwasreportedfollowingtheuseofNTRI inresinblocksandextractedteeth(Baumann&Roth1999,Gluskinetal.2001).ThepotentialclinicaladvantagesofusingNTRIwereinvestigatedbyMolander et al. (2007) and Reit et al. (2007), who implemented acomprehensive education programme in the Gothenburg Public DentalHealthService (DHS) starting in June2000.All the clinics in theDHS (25 clinics/148dentists)wereenrolledinthestudy.Theclinicswererandomisedtooneoftwoeducationprogrammes.

One of the education programmes included a four-hour lecture in root canalinstrumentation and the concept of the NTRI technology (L Group). Thepractitionersintheothereducationprogrammeparticipatedinthesamelecturecourse but attended an additional six-hour hands-on practical training course(HOGroup).Inthefirstpartofthestudy,thedentistsatsevenclinicsattendedthelectureprogrammeandsixclinicsparticipatedinthehands-oneducation.Inthispart, theGDPsat the remaining12 clinics servedas controls.The controlclinicswereeducatedinoneofthetwoprogrammeslaterinthestudyperiod.

At baseline, 4% of the dentists used NTRI. After a six-month clinical trainingperiod, the adoption rate of NTRI increased to 73%. However, a lecture incombinationwithhands-ontrainingresultedinahigherrateofadopters(94%)thanalecturewithouthands-on(53%)(Reitetal.2007).Thefrequencyofgoodqualityrootfillingsincreasedfrom31%to51%intheLGroupandfrom27%to47% in the HO Group. However, no statistically significant decrease wasregisteredinthefrequencyofpoorqualityrootfillings.

Afterthestudyperiod,all thedentistsweregraduallygivenhands-ontraining,thoseintheLGroupsaswellasallnewemployees.Toinvestigatethelong-termadoptionrateintheorganisation,afollow-upwasconductedfouryearsaftertheimplementation. The utilisation rate was still high, reaching 88% (Reit et al.2007).


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Lisbeth Dahlström

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Background

While treating patients, dentists most frequently work alone with a nurse intheir surgery. Although there are many practitioners working together in aclinic, they generally have only limited insight intowhat others do, how theyreasonandhowtheyperform.Socialintegrationamongcolleaguesisnotagivenataworkplaceanditisnotunusualfordentiststoworkatsingle-handedclinics.Interaction between people has been described as an important factor forstayinguptodateandforwhatpeopleaccomplishatwork.Inastudyofdoctors,Coleman et al. (1966) described the way different patterns of interpersonalcommunicationinfluencedthediffusionofaninnovationwithinanetwork.Thetimetakenfordiffusionandadoptionwassubstantiallyshorteramongdoctorswithmanyindividualnetworks(discussions, friendshiporadvice)thanamongthose who were socially isolated with few interpersonal relationships.Furthermore, ithasalsobeensuggestedthatsocial isolation isassociatedwiththe performance of professionals. Studies among practitioners in theUKhaveshownthatpoorlyperformingdoctorsareoftenisolatedandnotawareoftheirgaps in knowledge and skills (Bahrami & Evans 2001, Ashworth et al. 2011,Holdenetal.2012).Interactinginnetworksprovidestheopportunitytodiscusscases and new techniques. Study II was performed on the hypothesis thateducationandtheconcomitantactivationoflocalnetworkswouldincreasetheadoptionrateofNTRIandimproveroot-fillingquality.Inaddition,therewasanidea that the rate of poor root fillingswoulddecrease. In the programme, thepracticaltrainingwasrelocatedtotheindividualclinicsusingatrainedGDPasthe instructor (coach). The idea was that this would open the door todiscussionsandtheexchangeofexperience.

Participants

Thestudywasperformedatorganisationlevel.AllactiveGDPsatthe25clinicsintheSödraÄlvsborgDHSinJanuary2004(n=90)wereincluded.Initially,thepractitionersateachclinicchoseacolleagueamongthemselvestobetrainedasacoach.

Education

Atthestartofthestudy,thecoacheswereeducatedbyaspecialistaccordingtotheGothenburghands-onprotocol;afour-hourlectureandsixhoursofhands-ontraininginNTRI.Afterasix-monthtrainingperiod,thecoachesreunitedfora“kick-off” before the upcoming education at the clinics. At this time, theremaining GDPs attended a lecture given by the same specialist. The coaches

Lisbeth Dahlström

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thenconductedthepracticaleducationattheirclinic.Itwasarequirementthatthiseducationshouldincludecollectivehands-ontrainingaswellasdiscussions.

Datacollectionandassessment

Questionnaires identical to those in the Gothenburg studies were used atbaselineandaftersixmonths’training.

The coach at each clinic collected and coded the radiographs of the twomostrecently root-filledmolars from each dentist, just before and sixmonths afterthe training. Only radiographs from practitioners contributing cases pre- andpost-educationwere included in the study. The radiographswere assessed asdescribedinStudyI.

ResultsStudyII

Adoption

At the start of the study, 21% used rotary instrumentation. At the end of thestudy,79of the initial90dentistswerestillactive in theSödraÄlvsborgDHS.Theresponseratetothequestionnairewas97%(77/79).Eighty-eightpercentoftherespondersreportedusingNTRI.At75%oftheclinics,alltheGDPsusedrotaryinstrumentation.Atthethreelargestclinics(6-9dentists/clinic),95%ofthe practitioners used NTRI. At ten smaller clinics (3-5 dentists/clinic), theadoptionratereached88%,while,atthesmallestclinicswithoneortwoGDPs,thenewtechniquewasacceptedby85%.Inonlyoneclinichadaminority(twooffivepractitioners)adoptedNTRI.

Root-fillingquality

Radiographs before and after the education were submitted by 84% of thedentists(66/79).Twohundredandsixtyrootsin128teethbeforetheeducationand260rootsin110teethaftertheeducationwereevaluated.Theproportionofgoodroot fillings (score1) increased from45%to59%(P=0.003),butnosignificant decrease in verypoorquality (score5)was registered.Thequalityscore (score 1/score 5) increased from 5.36 (118/22) to 9.5 (133/14). If thedecreaseinscore5hadbeenduetoanincreasedfrequencyofscore4,noactualpositiveeffectwouldhavebeenachieved,asscore4stillrepresentedadefectiveseal.Forthisreason,wealsoincludedscore4inthequalityscore(score1/score4+score5),resultingin2.87(118/19+22)beforeand4.9(133/13+14)after


12

theeducation.Theresultfor“educationalbenefitratio”wasfoundtobesimilar(9.5/5.4=1.8 and 4.9/2.87=1.7), irrespective of whether or not score 4 wasincluded.

Aminority(11/66)oftheGDPswerefoundtoproducehalfthepoorqualityrootfillings, Seventy-three of the poorly performing practitioners reported usingNTRI.

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3.2 Studies III and IV

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Bender&Ewbank1994,Kitzinger1994).Itisthedynamicsingroupprocessesthatarethoughttohelppeopleexploreandclarifytheirviews(Krueger1994).Moreover, the interaction contributes to a high level of validity, becausewhatthe interviewees say can be contradicted, reinforced or confirmedwithin thegroup(Kitzinger1994,Krueger1994,Morgan1996).

Focus-groupinterviewsaresemi-structured.Inordertostayfocusedduringtheinterviews, a set of predetermined open-ended questions focusing on thesubject(aquestionroute)isdeveloped.Normally,focusgroupsconsistofsixto12 people. The participants are selected due to their relationship to the topicthat is intended for discussion (Krueger 1994,Morgan 1996). Smaller groups(three to five interviewees) are suitable for topics that generatehigh levelsofinvolvement, such as when participants have specialised knowledge and/orexperience to discuss. Larger groups work well on neutral topics generatinglower levels of involvement (Krueger1994,Morgan1996).Todetectpatternsandtrendsacrossgroups,multiplefocus-groupinterviewsareneeded(Krueger1994,Morgan1996).Itisrecommendedthatfocusgroupsshouldbecontinueduntilthedatabecomes“theoreticallysaturated”,meaningnonewinformationiselicited. Most often, this kind of saturation is reached after three to fourinterviewsandprojectsgenerallyconsistof threetosix focusgroups(Krueger1994,Morgan1996).

Qualitativecontentanalysisingeneral

Content analysis is a method for analysing text material in various steps.Initially,themethodwasusedinresearchonmassmediaandwarpropaganda.Themethod isasystematic,replicabletechniqueforcompressingmanywordsoftextintofewercontentcategoriesbasedonrulesofcoding.Thepurposeistoprovideknowledgeandnewinsight,aswellasbeingapracticalguidetoaction(Krippendoff2004).

Currently, two principal approaches are used, quantitative content analysis,often used in media research, and qualitative content analysis, used, forexample,innursing.Innursingresearch,avarietyofdatacanbeused;printedinterviewandvideorecordings,journalsandobservationprotocols.

Qualitativecontentanalysishasbeendescribedasasuitablemethodwhenthefocal point is identifying consensus and diversity among the participants(Graneheim&Lundman2008).Ifastudyisperformedonthebasisofpreviousknowledge and the purpose is theory testing, a deductive content analysis isused. However, if there is limited former knowledge of a phenomenon, aninductive approach is chosen (Elo & Kyngäs 2008). An approach based oninductive data moves from the specific to the general, so that patterns andregularitiesaredetectedbyspecificobservationsandthencombinedintolarger

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W(2,&) 2-) 6&1&-+,) $'+'&/&1'$H)v9+,#'+'#@&) >21'&1') +1+,7$#$)/+7) 32>9$) 21) &#'(&-)'(&)/+1#3&$') 2-) '(&) ,+'&1') >21'&1'H)J2'()/+1#3&$') +15) ,+'&1') >21'&1')5&+,)W#'()#1'&-0-&'+'#21V)%9') '(&-&) #$) +)5#33&-&1>&) #1) '(&)5&0'()23) '(&) #1'&-0-&'+'#21H)X(&)/+1#3&$') >21'&1') -&3&-$) '2) W(+') '(&) '&`') a$+7$bV) '(&) @#$#%,&) 2-) 2%@#29$)>2/021&1'$V)+,$2)&`0-&$$&5)+$)a$'+7#16)>,2$&)'2)'(&)'&`'bH)81)>21'-+$'V)'(&),+'&1')>21'&1') 5&+,$) W#'() W(+') '(&) '&`') +>'9+,,7) /&+1$V) +$0&>'$) #1@2,@#16) '(&)#1'&-0-&'+'#21) 23) '(&) 915&-,7#16) >21'&1'V) W(+') #$) $+#5) %&'W&&1) '(&) ,#1&$)PA-+1&(&#/)m)"915/+1)BCCTQH)81);'95#&$)888)+15)8_V)'(&)+00-2+>()5&$>-#%&5)%7)A-+1&(&#/)m)"915/+1)PBCCTQ)W+$)+00,#&5)+15)#$)5&$>-#%&5)%&,2WH)

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16

ParticipantsinStudiesIIIandIV

ThegeneraldentalpractitionersusedinStudiesIIIandIVhadpreviouslybeeninvolved in the implementation ofNTRI inGothenburg (Molander et al. 2007,Reit et al. 2007), as well as in Study I. In order to include different socio-economic areas, located both centrally and peripherally, seven public dentalhealthclinicswereselected(withaminimumoffouractivedentists,theheadofthe clinic excluded). Each clinic formed one group. Initially, a set of seveninterviews,eachconsistingoffourtosixdentists,wasplanned.

All the heads of the public dental health clinics in the Gothenburg area wereinformed about the study by the management of the organisation. Theorganisationalsoguaranteedremunerationtotheclinicsbasedonthenumberof dentists participating and the duration of the interview. The heads of thechosenclinicswerecontactedbyphoneandtheyallagreedtoparticipate.Theysubsequentlyreceivedwritteninformationinordertoinformthestaffabouttheproject. They then provided the research group with a list of the dentistsavailableatthesettime(headsoftheclinicswereexcluded).Thedentistsonthelistswerecontactedbye-mailonemonthbefore thescheduled interview(oneclinic was excluded due to too few dentists being available). They wereinformed about the study and asked if theywanted to participate. Theywerealsoinformedthatthesessionwouldbevideorecordedandthattheycouldendtheirparticipationwhenevertheywanted.Inall,33GDPswerecontacted.Threedentists declined to participate: one for unknown reasons and two who hadrecentlygraduatedandthoughtthattheyweretooinexperienced.OneGDPhadacceptedbutfailedtoappearduetoillness.Inall,33dentistswereinterviewed(fourGDPsinapilottestwereincluded).

DatacollectionStudiesIIIandIV–thefocus-groupinterviews

The question route used in Studies III and IV was constructed by the fourauthors in collaboration (Appendix 1). To increase validity and reliability, anexternalassessor,anendodontistexperiencedinqualitativeresearch,reviewedthequestions.

In everyday clinical practice, dentists base the assessment of the technicalqualityofarootfillingalmostexclusivelyonitsappearanceintheradiographicimage.With the aimofmimicking a situationof this kind, the firstpart of thefocus-group discussion was based on radiographs shown on a video screen.(ThispartofthediscussionwasonlyusedforanalysisinStudyIV.)Inordertoselect appropriatematerial for the focus groups, 17 radiographs (37 roots) ofmixed root-filling quality from Studies I and II were selected and sent to theparticipants one week before each interview. On a premade form, they wereasked to evaluate the 37 roots according to the technical quality of the root

Lisbeth Dahlström

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filling (goodorpoor)andsuggest furthermonitoringof thecase if thequalitywasassessedaspoor(acceptornotaccept).Tostimulatethediscussioninthefocusgroups,thethreecaseswiththemostdivergentopinionsaccordingtothequestionnaire were selected. No contextual information about the cases wasadded. The practitioners were encouraged (with an option to point at thescreen) to describe the root filing as precisely as possible. The dentists werealsourgedtodiscusstherootfillingandcometoadecisiononhowtomonitorthe case.Moreover, theywereaskedaccurately toaccount for their choice forhandlingthecase.Tomakethedataricher,questionslike“Couldyoudescribe?”,“Would you explain further?”, “What do youmean?”, “Is there anything else?”wereaddedduringtheinterviews.

As recommended by Krueger (1998b) and Malterud (1998), all the sessionswere conducted as teamwork between the moderator and an assistantmoderator. The moderator (LD) conducted the interviews and the assistantmoderator (OL) was responsible for video recording and assisted at a shortpost-meetinganalysisof thesession.All the interviewswereperformedat theclinics.ThedatacollectionstartedinJune2012andendedinMay2013.

DataanalysisStudiesIIIandIV–qualitativecontentanalysis

The data consisted of the transcribed text from the seven focus-groupinterviews.Afterverbatimtranscriptionof the interviews,byLD(four)andanassistant, the material was analysed using qualitative content analysis(Graneheim&Lundman2004). Toreducethelargetextmaterial,thetextwassectioned into smaller units;meaning units,meaning sentences or paragraphscontainingaspects related toeachother, or coherent,distinctmeanings in thedocument. The meaning units preserved the integrity of the idea that wasexpressed.Afterthis,themeaningunitswereshortened.Thisstepisdescribedascondensation,referringtoaprocessofshorteningbutstillpreservingthecoremeaning.Thecondensedtextwasthenabstractedtoa“higherlogicallevel”.Theabstraction in Studies III and IV is represented by the creation of codes andcategories.Creatingcodesisalsoreferredtoaslabellingthecondensedmeaningunits.Codeswithsimilarcontentwerethenarrangedintocategories.Acategoryanswers the question “what” (Krippendorff 2004) and refers, according toGraneheim&Lundman(2004),toadescriptivelevelofthecontentorprovidesameansofdescribingthephenomenon.Inthisway,StudiesIIIandIVdescribethemanifestcontentofthedatausedinthestudy.


18

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Lisbeth Dahlström

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Table1.DescriptionofthecategoriesfoundinStudyIII

Thecategories Shortdescriptionofthefindingscontributingtotheexperiencedcomplexity

ofRCTandthenegativeemotions

Clinicalprocedure • Novisualcontrol• AllstepsinRCTaredifficult• Unpredictableroot-fillingqualityat

completion• Illogicaloutcome

Equipment/materials • Awkwardinstruments• Complicatedequipment• Difficulttoadjustroot-fillingmaterial

Competenceofthedentist • QuestioningtheirownabilitytoperformRCT

• Strivingtodotheirbestbutsometimeshadtocompromiseontheroot-fillingquality(“goodenough”)

• AfeelingofnotbeingupdatedTooth • Posteriorteethdifficulttoreach

• Anatomicalcomplicationsdifficulttohandle

Patient • Complicatedpersonalityorbehaviour

Organisation • Restrictedfreedom• Minimumincomeperhour/often

unabletocompleteacasewithintheremunerationlimits

• Limitedinfluenceoverpurchaseofequipment/materials

• Limitedresourcesforcontinuingeducationinendodontics


20

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Lisbeth Dahlström

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21


22

3.3 Main findings

StudyI

o TheincreasedrateofgoodqualityrootfillingsaftertheimplementationofNTRIwasmaintainedatthelong-termfollow-up.

o Therateofpoorqualityrootfillingshadnotdecreased.Everysixthrootfillinghadapoorseal.

StudyII

o EducationinNTRIincreasedtheadoptionrate,althoughthehands-onpartwasperformedbyatrainedGDP.

o EducationinNTRIincreasedthefrequencyofgoodqualityrootfillings,althoughthehands-onpartwasperformedbyatrainedGDP.

o EducationinNTRIandtheconcomitantactivationofprofessionalnetworksdidnotreducethefrequencyofpoorqualityrootfillings.

StudyIII

o RCTwasassociatedwithhighemotionalstresslevels.o RCTwasregardedascomplexanddifficult,oftenperformedwith

uncertainty.o Sixcategoriesofissueswerefoundastheoriginoftheproblems:theclinical

procedure,theequipment/materials,thecompetenceofthedentist,thetooth,thepatientandtheorganisation.

o TheGDPshintedthatoptimalqualityshouldnotbeexpectedingeneraldentistryandproposedtheconceptof“goodenough”treatment.

StudyIV

o Theradiographsdidnotprovideasufficientbasisforthedecisiononwhetherornottoacceptapoorqualityroot-filling,“ad–hoc”considerationswerealwaystakenintoaccount.

o Theconsiderationswererelatedtoearlierclinicalexperiences,orputinacontextualperspective.Threecontextualcategorieswereidentified:pulpalandperiapicaldisease,evaluationofrisksandconsumedresources.

o Awell-thought-out“goodenough”treatmentconceptdidnotexist.Itwasalwaysthespecificsituationsthathadadecisiveimpactonthedecision.

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3.4 Ethical considerations

Ethical approval forStudy Iwas givenby theboardof theGothenburgPublicDentalHealthServiceandforStudyIIbytheboardoftheSödraÄlvsborgPublicDentalHealthService.Althoughparticipation intheeducationprogrammeandthestudywasmandatory,itisunlikelythatharmwasinflictedduetothestudysituation.Radiographsandquestionnaireswerecodedattheclinicsbeforetheywere sent to the study group.However, although anonymitywas sought, dataobtained from single participantsmight unintentionally have been possible toidentify.

EthicalapprovalforStudiesIIIandIVwasgivenbytheboardoftheRegionalEthical Review Board in Gothenburg (No 238-13). Prior to the focus-groupinterviews, all theparticipantshadbeencontactedbye-mailwith informationabout the study and the fact that participation was optional. Before theinterview,theyalsohadtosignaninformedconsentform,includinginformationabouttheproject,theopportunitytoterminateparticipationatanytimeandtorespecttheconfidentialityofthediscussionstakingplaceduringtheinterviews.Inordertoenablethedentiststofeelfreetotalk,theheadsoftheclinicswerenot allowed to participate in the interviews. Codes were used in thetranscriptioninsteadoftheparticipants’names.Quotationswerefurthercodedinordertoensureconfidentialityaccordingtoclinicsandindividuals.


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4 METHODOLOGICAL CONSIDERATIONS

4.1 Studies I and II: Quantitative methods

Assessmentofradiographs

The assessment of radiographs always involves the risk of misinterpretation.Inter-observer variations have been reported and individual observers maychange their assessments over time. For example, Reit & Hollender (1983)observed difficulties in defining and maintaining criteria in radiographicevaluationsof the conditionsof theperiapical tissues aswell as thequalityofthe seal of the root canal. Eckerbom&Magnusson (1997) reported statisticaldifferences between the authors for the recordings of an adequate orinadequateseal.

Theassessmentof theroot-fillingquality inStudies IandIIwasmadeononlyone intra-oral orthoradial projection.Due to the limited reproducibility of thelateralseal(Kerstenetal.1987,Eckerbom&Magnusson1997),therateofgoodqualityrootfillingsmayhavebeenoverestimatedand,consequently,therateofpoorqualityrootfillingsunderestimated.However,theestimationofthelengthmay have been more reproducible, as one radiographic projection has beenshowntobereliablewhenestimatingthelengthoftherootfilling(Eckerbom&Magnusson1997).Moreover,inrootswithtwoormorecanalsoverlappingeachother, good root-filling quality may have been overestimated. In order tominimiseerrorsat theassessments,all caseswereblindedto theobservers intermsofpre-orpost-educationsamplesandtheradiographswerepresentedinrandomorder.Further,twoobservers(LDandAM)madetheassessmentsandstrictcriteriaweresetbeforethestartoftheexamination(Goldmanetal.1972,Eckerbometal.1986).Totesttheintra-observeragreement,50rootswerere-examinedafteronemonth.Thekappavaluereached0.85,whichisregardedasverygood(Landis&Koch1977).

Thescores

The quality score constructed by Molander et al. (2007) was used forradiographic evaluation. The length was evaluated as correct if it terminatedwithin2.5mmfromtheradiographicrootapex.Caseswithasurplusofsealermaterialwerejudgedascorrect if theapicalpreparationendedwithin2.5mm

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oftheapex.Thequalityofthesealwasassessedintheapicaltwo-thirdsofthecanal.

Score1

Score2 Score3 Score4Score5

Good Verypoor

Length x x - x -

Seal x x x - -

Taper x Atleast

Notevaluated

Notevaluated

Notevaluated

Transport - onedefective

Notevaluated

Notevaluated

Notevaluated

Thescalethatwasusedhasobviouslimitations.Thedifferentscoresrepresentordinaldatarepresentedbyqualitativevariables(fromscore1,goodquality,toscore5,verypoor).Forexample,score2(correctlength,goodseal,taperlackingand/or transportation) should represent a better score than score 4 (correctlength, poor seal). However, if there is an extreme transportation (score 2),therearepartsofthecanalthatwillnotbeinstrumentedandcleanedandthiswouldthereforenotrepresenthigherqualitythanscore4.Intheresults,score2wasrepresentedbyasmallquantity (0.4-5.7%)andwasnot furtheranalysed.Score3includesrootfillingsthatarebothtooshortandtoolong.Moststudiesreportat tooth level,but, inastudyusingtherootasaunit,shortroot fillings(>2 from the radiographic apex) have been reportedwith a higher rate of AP(25%)thaniftheyendwithin2mmfromtheapex(17%),whilethehighestrateofAPwasfoundinoverextendedroot fillings(37%)(Bergenholtzetal.1973).Due to toothanatomy, it isnot alwayspossible to reachan ideal lengthandashort (but adequately sealed) root filling may therefore be the best possibleresult. However, a root filling ending beyond the radiographic apex in a fullydeveloped tooth is due in most cases to over-instrumentation. In the scoresystem,shortandlongfillingswerenotseparated.

InStudiesIandII,theemphasisisplacedontheendpointsofthescaleandaso-called quality ratio was calculated (score 1/score 5) (Molander et al. 2007).However,thequalityratiodidnotaccountforapotentialmovementfromscore5 to score 4, which would have barely any effect on quality as related totreatment outcome. So, in Study II, the quality ratio was modified, (score1/score 4+5). Calculations between the two quality ratios showed that theeducational benefit was similar, regardless of whether or not score 4 wasincluded.


26

Differentstudiesofroot-fillingqualityaredifficult tocompare,as therearenostandardisedevaluationcriteriaandtheradiographictechniquemayvary.

Control

Sincetheindividualcoachwasfreetoorganisethehands-ontraininginStudyII,thedesignmayhavevariedbetweentheclinics.Thesevariationswerenottakenintoaccount.Thismirrors theeffectofanon-controlleddelegatededucationalintervention within an organisation. In order to study the full effect of theinterventionatorganisationallevel,thecoacheswereincludedinthestudy.

4.2 Studies III and IV: Qualitative methods

Thestrengthsofthequalitativeresearchmethodologyused

Interaction within a focus group will stimulate new thoughts and theparticipants have the opportunity to question each other and to explainthemselvestoeachother.Thisinteractionoffersvaluabledataontheextentofconsensus and diversity among the participants (Morgan & Krueger 1993,Kitzinger1994,Graneheim&Lundman2008).

Since the conditions that influence root-filling quality are a somewhatunexploredfield,thefocusgroupsenabledabroad,open-endedapproachtotheproblem. In the discussions, the interviewees appeared to be engaged in thediscussions and comfortable sharing their opinions and experiences. Richmaterialwasthereforeobtained.TherewerenomajordifferencesregardingtheperspectiveonRCTbetweentheclinicsandsothedataweresaturatedafterthefirstfewinterviews.

Theweaknessesofthequalitativeresearchmethodologyused

One challenge when planning a focus group is the development of adequatequestions. The questions must focus on obtaining information that directlyrelatestothestudyobjectivesandthequestionsneedtobeconversationalandeasy for the participants to understand (Krueger 1998a). Emphasis was

Lisbeth Dahlström

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therefore placed on the planning of the “question route” and all four authors,representingawidevarietyof research traditionsandareas,were involved inthe planning. Further, an external assessor, an endodontist experienced inqualitative research methodology, reviewed the questions and the questionswerefinallytestedinapilotinterview.

Themoderator has a crucial impact on the result of a focus-groupdiscussion.Themoderatorshouldunderstandthesubjectandmustmaketheintervieweesfeelcomfortableenoughtosharewhattheythinkandfeel.Themoderatormustalsobeable tocontroldominantspeakersandencouragehesitantparticipantstospeak.ThemoderatorusedinStudiesIIIandIV(LD)attemptedtofulfilalltherequirements for being a suitable moderator and the performance wasevaluatedandapprovedintheanalysisofthepilotbeforethefocusgroupstookplace at the clinics. Further, a co-moderator, well experienced in qualitativeresearch (OL), was present at the interviews, conducted the video recordingsandwasalsoavailableforashortpost-meetinganalysisofthesessions.

Qualitativeresearchmethodsoftenproducelargeamountsoftext,asinStudiesIII and IV, and, although the data were re-evaluated several times and theanalysiswasperformed“withanopenmind”,particularissuesmighthavegoneunnoticed. There is also a risk that personal experience and knowledge willinfluence the interpretations and conclusions.However, the four authorswiththeir variety of experience were involved in the interpretation. The risk ofmissing information and obtaining biased results was therefore reduced.Moreover, there is an inherent limitation when evidence is based on self-reported experience. Experience is not observable per se and the data aredependent on the participants’ ability to recollect their experiences and theeffectivenesswithwhichtheycommunicatethroughlanguage.Informationandnuancesmay be lostwhen oral expressions are transcribed intowritten text.Further,thetranslationofsentencesandexpressionsfromonelanguage(inthiscase Swedish) to another (English) entails obvious risks of changing thelinguistic meaning (Polkinghorne 2005). The authenticity of reportedstatements,opinionsandexperiencesmaynotbeconfirmed.However,asclaimswere either questioned and further discussed, or confirmed within the focusgroups, there isgoodreasontobelieve that theopinionsexpressedduring thefocusgroupsmirrortheparticipants’trueexperiences(Kitzinger1994).

Asinmoststudiesbasedoninterviews,thenumberofparticipantswaslimited.However, as the data were saturated, more participants would probably nothaveinfluencedtheresult.Further,onlypublicdentistswithinalargecitywererepresented.It isnotpossibletoascertainwhetheramixofpublicandprivatedentists or urban and rural practitioners would have modified the results.However, itmustberememberedthattheaiminqualitativeresearch isnottogeneralisebuttounderstandaparticularphenomenon.Itisuptothereadertodecide whether or not the results can be transferred to another context(Graneheim&Lundman2004).


28

Trustworthiness

Although some investigators prefer to use the concepts of validity, reliabilityandgeneralisability (primarilyassociatedwithquantitativeresearchmethods)whenevaluatingqualitativeresearch,mostauthorsofqualitativestudiesusetheconceptsofcredibility,dependabilityandtransferabilitytodescribethevariousaspectsoftrustworthiness(Graneheim&Lundman2004).

• Credibility:confidenceinthe“truth”ofthefindingsPrior to the focusgroupsat theclinics, the full implementationprocedurewastested in apilot project among former fellowGDPs.Onlyminor changesweremade (the pilot was included in the study). The participants representeddifferent ages and experience and they worked in different socio-economicareas.Ourchoiceofmethodsmustberegardedassuitable forthetask.All theidentified categories were conceptually and empirically grounded and thecontentofthecategorieswaswelldefined.Further,thefindingswerevalidatedbyexpertsinquantitativeresearchmethodology(HR&OL)andrepresentativequotationswereselectedfromthetranscribedtext.

• Dependability:whetherthefindingsareconsistentandcouldberepeatedTherewasanopendialoguewithin the researchgroup.Using joint reflectionsand discussions, the codes and categories became more stringent during theanalysisprocess.

• Transferability:whetherthefindingshaveapplicabilityinothercontextsThe context, selection and characteristics of participants, as well as datacollection and the analysis process, are described. The findings are wellpresentedandillustratedbyappropriatequotations.Thereshouldbepotentialfortheresultstoberepresentativeforotherdentistsinsimilarcontexts.

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5 GENERAL DISCUSSION

“A doctor’s on-going learning is a journey across a practice lifetime, whichinvolves the doctor as a person, interacting with their patients, other healthprofessionalsandthelargersocietalandcommunityissues”(Handfield-Jonesetal.2002).Unlessperformanceis influencedby“something”,thereisariskthatclinical performance will decline over time. Technology and knowledge areconstantlyadvancingandpractitionersthatarenotableorwillingtochangewillunavoidablybeleftbehind.

The premise for this thesis was the discrepancy in the rate of apicalperiodontitis registered in root-filled teeth in controlled clinical studies andcross-sectional epidemiological studies. The rationale for the thesis was toexploreoptions toreduce thisdiscrepancy.Whatreallydeterminesroot-fillingquality in general practice is a fairly unknown field.However, the reasons forpoor performance must be assumed to be multifaceted, as dental practicecomprises not only individual dentists with their own personalities andqualifications but also the context in which the treatment is performed. Twodifferent approaches were therefore used; one aiming to increase root-fillingqualitybyimplementinganewtechniqueandoneaimingtobetterunderstandthereasonsforpoorqualityrootcanaltreatment.

5.1 Root-filling quality and apical periodontitis

Studies I and II indicate that education inNTRIwill improve the rate of goodquality root fillings and that an improvement of this kind might persist overtime. In accordancewithother studies, approximately50%of the root fillingsshowedgoodqualityaftertheimplementation(Molanderetal.2007,Göranssonetal.2014,Kochetal.2015).

Studies that analyse quality in greater detail reveal that AP is less frequentlyfoundingoodqualityrootfillingsthaninconnectionwithpoorrootfillings.Forexample,usingdatafromaSwedishpopulation,Peterssonetal.(1986)reportedthat,inteethwithcompletelyobturatedcanals(nolateralorapicalcanallumenvisible),only7%wereassociatedwithaperiapicallesion,while,ifthecanalwasincompletelyobturated,anapicallesionwaspresentin45%.Fromanotherset


30

of Swedishmaterial, Frisket al. (2008) reported that the risk of havingAP inteethwith a root filling of the correct length (0.5-2mm from the radiographicapex) was almost three times higher in inadequately sealed teeth comparedwith teethwithadequateroot fillings(30%to10%).ThehighestriskofAP inroot-filled teeth is seen when incompletely sealed root fillings are combinedwithoverfill. In these cases, bone lesionshavebeen reported tobepresent in55-74%(Bergenholtzetal.1973,Peterssonetal.1986,Frisketal.2008).

Despitethefactthatstudiesreport improvingroot-fillingqualityovertime,nocorresponding statistically significant improvement in periapical status hasbeenseen(Petersson1993,Kirkevangetal.2001b,Eckerbometal.2007,Frisketal.2008,Kochetal.2015).However,moreretainedmolarsmaybepartofthiscontradictoryfinding.Forexample,Frisketal.(2008)reportedagreaterlossofmolars in1973 comparedwith2003and root-filled teethwithAPmighthavebeen extracted in the earlier material. Kirkevang et al. (2001a) found thatmolarsweremorefrequentlyassociatedwithAPthanothertoothgroups;moremolarswere endodontically treated (molars8%, other2.5-5.5%) andmoreoftheroot-filledmolarshadAP(molars65%,other38.5-44%).

Although the risk of AP is reduced in good quality root fillings, some studiesindicatethatAPisstillfoundinmorethanonethirdoftheseteeth(Saundersetal. 1997, Kirkevang et al. 2000, Segura-Egea et al. 2004). This indicates thattherearefactorsotherthanjustthetechnicalresultasseenontheradiographthat influence the outcome. Although many potential factors have beensuggestedintheliterature,thereallycrucial factorfortheoutcomeiswhetheror notmicroorganisms are present in the root canal system (Kakehashi et al.1965).

Several clinical studies have shown that the pre-treatment diagnosis is ofimportancefortheprognosis.Thehealingrateisfoundtobelowerinteethwithapre-operativediagnosisofAPthaninteethwithout(Strindberg1956,Kerekes&Tronstad1979,Sjögrenetal.1990,Ngetal.2011).

The radiographs do not say anything about possible microbial contaminationduringthetreatment.Althougharubberdamisregardedasthestandardofcareinmodernendodontics(EuropeanSocietyofEndodontology2006),ithasbeenreported that it is irregularly used in general dentistry. For example, inDenmarkandBelgium,3-6%and, inEngland/Scotland,19-25%ofthedentistsreported using a rubber dam as a standard procedure (Saunders et al. 1999,Jenkinsetal.2001,Slaus&Bottenberg2002,Bjørndal&Reit2005).However,thenumberofusersappearstobehigherinSweden.Kochetal.(2009)reportedthat90%useitonaregularbasis,althoughsomereportoccasionalexceptions.Further, despite the fact that irrigant solutions are recommended to havedisinfectant and organic debris-dissolving properties (European Society ofEndodontology2006),manydentistsprefersolutionswithouttheseproperties,

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whichmaycontribute toan increasedriskofpersistent infection (Saundersetal.1999,Whitworthetal.2000,Jenkinsetal.2001).

Alsothecoronalsealhasbeenfoundtoinfluencethetreatmentoutcome.FromDanish material, Kirkevang et al. (2000) reported that satisfactory coronalrestorations were associated with better periapical status (48%) thanunsatisfactoryrestorations(64%).Whenallthefactors(seal,lengthandcoronalrestoration)werecombinedintheassessment,theprevalenceofAPwaslowerif all the factorswere scored as adequate (31%) comparedwithwhen all thefactorswerescoredasinadequate(78%).

5.2 Adoption pattern and poor performance

In Study II, several dentistswere found to produce a single poor quality rootfillingeitherbeforeorafterthetraining.Thestudyalsoshowedthataminorityofthepractitioners(17%)producedhalfthenumberoftheassessedpoorrootfillings during the study period. Among the poorly performing practitioners,there was a higher degree of non-adopters of the NTRI technique comparedwith the restof the studygroup. InRogers’ (1983) termsof adoptionpattern,thesecanbeclassifiedas“laggards”or“traditionals”,meaningthattheyarethelast to adopt an innovation. These individuals typically have an aversion tochange and have also been shown to have few social contacts. In a classicalstudyof thediffusionofmedical innovations, Colemanet al. (1966)describedthe importance of social contacts in networks. They found that the adoptionpattern was markedly influenced by the personality of the doctor; sociallyintegrated doctors were far more inclined to adopt new innovations thansocially isolated doctors. Further, studies indicate that poorly performingdoctorsareoften isolatedandnotawareof theirgaps inknowledgeandskills(Bahrami & Evans 2001, Ashworth et al. 2011, Holden et al. 2012). SimilarresultshavebeenfoundbyKruger&Dunning(1999),whostatedthat”unskilledindividualssufferadualburden:notonlydotheyperformpoorly,buttheyalsofail to realise it”. So, there appears to be an association between adoptionpattern and performance. This is in linewith the findings of Göransson et al.(2014)whoreportedanincreaseingoodqualityrootfillingsfrom12%to46%amongadoptersofNTRIcomparedwith12%to16%amongnon-adoptersaftereducationinrotaryinstrumentation.

The activation of local/professional networkswas tested in Study II in that atrained GDP from each clinic conducted the NTRI hands-on training withcolleagues at his/her clinic. Although discussionsweremandatory during thetraining, thiswasnotenoughtoestablishprofessionalnetworks foracollegial


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exchangeofexperienceand feedbackwithaview to reducing therateofpoorrootfillings.

5.3 Factors that might obstruct professional development

During the focus-group discussions, the GDPs described their view ofperforming RCT. Root canal therapy was regarded by most of them as morecomplexanddifficultthanotherdentalmanipulations.Severalpractitionerssaidthat theyregardedRCTas illogical, someto theextent that theyperceived thetreatmentasa “mystery”.Therewereseveralsituationsduring the treatmentsthat were described as inducing moods such as frustration and anxiety.Furthermore,manydentists senseda feelingof “lossof control” inassociationwithRCTandhighlevelsofstressandtimepressurewerefrequentlydescribed.InaccordancewithMcColletal.(1999),thetimepressuremostlyarosefromthefact that theallocated timeaccording to theremunerationwas insufficient.Nomatterhowadentisthandledthetimepressure,itwasalwaysrelatedtosomekind of stress. Regardless of whether the dentist chose to please theorganisation by not usingmore time than the fee allowed or if the treatmentwasallowedtoexceedtheallocatedtimeinordertoproducegoodquality,thedentistwouldconsequentlybedisloyaltotheotherparty.

Theoriesofprofessionaldevelopmentinrelationtostatementsduringthefocusgroups

Tobecomea competentpractitioner,Ryle (1949)andSchön (1983) state thattime for reflection is essential in order todetect a lack of knowledge, skills orunderstanding.Onlythroughreflectionwillapractitioneridentifyinadequaciesso that he or she can identify learning needs for improvement. However,considering the many stressful situations and time pressure described at thefocus groups, there appear to be limited opportunities to find the peace andquietneededtoreflectonendodonticperformance.

Further,without time for refection, clinicalprocedureswillbe repeated in thesame way as the time before and these practices will therefore become“routinised” (Eraut 1994). Eraut says that the development of routines is anatural procedure in life and a necessary process to be able to cope witheveryday work. Routines increase efficiency, but, without time for reflection,there is a risk that practice might fail to adjust to new advances and thus

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obstructprofessionaldevelopment.Among the interviewees, therewere thosewhodescribeddifficultieswithnewclinicalproceduresandbelievedthatitwaseasier to stick to routines unless the authorities told them precisely how tomakeachange.

However,formostpeople,reflectionontheirownpracticeandself-assessmentis not enough to obtain an insight into performance and learning needs. As acomplement, an external assessor such as a colleague or a peermay provideuseful feedbackasahelptoobtaining insight.Withoutcontinuous feedbackonperformance, there is a risk that clinical practiceswill be impaired over time(Haysetal.2002,Sargeantetal.2009,Prescott-Clementsetal.2011).However,indentalpractice,anaturalplatformforperformanceassessmentfeedbackdoesnot appear to exist. Although many dentists work in group practices withprofessional colleagues, clinicalpractice isperformed in single rooms, shutofffrom outside assessments. It is therefore possible that fallacies may beperpetuated without either the individual practitioner or his/her colleaguesbeing aware of it. One interesting finding at the focus groups that might beexplained by the lack of verbal criticism of technical results was the use ofvocabulary. When good quality root fillings were described, the GDPs usedtechnical termswithease,but,when it came toshortcomings, theyapparentlyhad difficulty finding words to describe exactly what they saw and insteadpreferredtousemetaphors.TheuseofmetaphorshasbeendescribedbyLakoff&Johnson(1980)asunderstandingandexperiencingsomethingweknowlittleaboutintermsofsomethingelsethatweknowmoreabout.Usingoneideaandlinkingittoanotherhelpsusbettertomakesenseofnewthings.Metaphorsarealso thought to enrich our everyday language and help us to shape ourcommunication.

Although feedback is important for developing insight into professionalperformance,Haysetal.(2002)alsodescribeessentialfactorssuchaswatchingothers practise, engaging in case reviews, motivation and the visibility ofprofessional norms. They also say that acquiring new knowledge and skillsrequiresthecapacitytochange.Thecapacitytochangeisdescribedasacrucialattribute throughout an entire career and implies that an individual has thecorrectinsightintohis/herpersonalstrengthsandweaknesses,butalsothatthemotivation to improve is present. In this context, Hays et al. (2002) defineinsight as a combination of three related constructs: awareness of one’s ownperformance (over time), awareness of the performance of others and thecapacity to reflect onboth thesemeasures andmakea judgement. It couldbeassumed that the lack of inter-professional exchange was the reason for theuncertaintyexpressedabouttheperformanceinRCTthatshouldbeexpectedingeneraldentistry.AshasalsobeenreportedbyMcColletal.(1999),therewasalack of insight into the practitioner’s own practice in that many dentistsquestioned their requirements for performing RCT correctly. In contrast,Bjørndal et al. (2007) reported that only 5% of Danish GDPs regarded theirperformanceasunsatisfactory,althoughKirkevangetal.(2000)foundthatroot


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fillings inDenmarkshowedhighratesof inadequatequality.However, itmustberememberedthatthestudybyBjørndaletal.originatesfromquestionnaires,while the results from Study III andMcColl et al. represent the results of in-depthinterviews.

Lackofknowledgeofmicrobiology

Severaldentistsfeltthatthediagnosisofthepulpalandperiapicaltissueplayedadecisivepart in thedecisiononwhetherornot to accept apoor root filling.However, further discussions revealed that therewere divergent ideas on thedefinitions of pulpitis and apical periodontitis, as well as on the origin ofendodonticinfections.Asaresult,theGDPs’conflictingperceptionsunmaskedalack of understanding of endodontic microbiology. Similar findings have alsobeenreportedbyBjørndaletal.(2007)whoreportedthat41%ofthedentistsassessed their knowledge of endodontic microbiology as not being up tostandard.

Further,itcouldbehypothesisedthatpartsofthefeelingof“lackofcontrol”canderive from the lack of understanding of microbiology. The comments thathealthy apical conditions couldbe founddespitepoorquality root fillings andunhealthy periapical conditions could be found in spite of good quality rootfillingsmight be part of the illogicality andmystery thatwas associatedwithRCT. The fact that there aremanypossible explanations for remainingmicro-organisms, in spite of a “good-looking” root fillingor the fact that apoor rootfillingmayhavepeenperformedunderasepticconditions ina tooth free frommicro-organismswasnotreflectedonbythepractitioners.

Generalpractitioners’reasonsforacceptingpoorrootfillings

In the decision on whether or not to accept a root filling that had just beenperformed,substandardrootfillingstendedtobemoreeasilyacceptediftherewereonlyminorradiographicsignsofapicaldiseaseorifthepatientdisplayednoclinicalsymptoms.ThisisinagreementwithBjørndaletal.(2007),whoalsoreported that GDPs did not follow the gold standard (periapical status andinfected root canal) but over-valued pre-operative factors as having animportantinfluenceonoutcome.Tosomeextent,thedatamayreflecta“praxisconcept” generated by Kvist et al. (1994). The “praxis concept” hypothesisesthat the practitioners imagine periapical health and disease as stages on acontinuous scale instead of an either/or situation. The cut-off point for thedecision to treat ornot is thought tobe valuedependent and, for this reason,huge inter-individual differences have been described. In a similar way, thefindings reported from the focus groups demonstrated inter-individual

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differencesinthedecisiononwhetherornottore-doarootfillingthatwasjustperformed.

The radiographic images shown at the focus groupswere not enough for thepractitioners to decide whether or not they should have accepted the rootfillings. Instead, theypresented a varietyof “ad-hoc considerations” (Garfinkel1967) in order to account for the decision they made. These considerationswere related to the assessment of pulpal and periapical health, evaluation ofrisksandfurthertoconsumedpersonaloreconomicresources.Theconsideredrisks were never related to probability values or to academic literature butinsteadtotheirownpractice,withtheemphasisonrecentnegativeexperiences.These grounds for decision-making have been observed by Tversky &Kahnemann (1974), who proposed that people rely on a limited number ofheuristic principles (rules of thumb) in decisions made with uncertainty. Forexample,subjectiveprobabilitymaybetheresultoftheeasewithwhichearlierevents can be remembered (availability principle). Moreover, the discussionsrevealed that it was impossible to specify in advance the considerations thatwouldberelevantinaparticularcase.Therewasnogeneralcriterionforarootfillingtobeconsidered“goodenough”.Contextualpropertiesthatweredecisivealways emerged from case to case. For example, a poor root filling could beaccepted if thepatientwas free fromsymptoms.However, if therewasa largelesion,thedentistputmoreeffortintoimprovingquality,atleastaslongastheworkcouldbeperformedwithinthetimelimitaccordingtotheremuneration.On the other hand, if a dentist’s personal resourceswere consumed (skills orenergy exhausted), a poor result would be accepted, regardless of othercircumstances.

5.4 Success in endodontics

Sound,asymptomaticorfunctional?

Fromanacademicpointofview,thecriteriaspecifiedbyStrindberg(1956)areoftenused inassessmentsof successand failure.Strindbergstated thatonlyatoothfreefromsymptomsandtheabsenceofperiradicularradiolucencycanberegarded as a post-treatment success. A precise definition like this reflects an“ideal”concept(JuulJensen1985),whichisexclusivelyfoundedonbiologyandis neutral to different clinical situations and agents. Strindberg based hisassessmentsonconventionalintra-oralradiographs.Today,thereisequipmentsuchascone-beamcomputedtomography(CBCT)thathasbeenshowntorevealalowerrateofhealingcomparedwithintra-oralradiography(Pateletal.2012).Asaresult,thebiologicaldefinitionofsuccessandfailureischallengedandthis


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alsogivesrisetoethicaldilemmas.Isitacceptabletoevaluatetheoutcomeofatreatment using a traditional method that is known to overvalue the successrate?Woulditberesponsibletodefygeneralguidelinesandexposeallpatientstoradiographicmethodscausingmoreradiationinordertobemorepreciseinevaluations (AmericanAssociationofEndodontists2015)?Shouldallpreviousstudiesofsuccessandfailureberegardedasout-dated?

However,atreatmentgoalbasedonstrictbiologicalcriteriadoesnotappeartoapplytogeneralpractitioners.InspiteofradiographicsignsofAP,only11-12%were revised during a 10- to 20-year follow-up period, meaning that almost90%of the remaining root-filled teeth diagnosedwithAPwere left untreated(Kirkevang et al. 2014, Petersson et al. 2015). Endodontic re-treatmentstrategies in general practicewere studied by Kvist et al. (2004). They foundtwo main types of strategy among Swedish GDPs: disease focused or illnessfocused. When illness was used as a criterion, the dentist would accept thetechnicalresultaslongasthepatientdidnotexperiencepain.Asimilartypeofreasoning was found at the focus-group discussions in Study IV. Somepractitioners said that they would have accepted poor technical qualityindependentlyofthepre-operativestatus,aslongasthepatientswerefreefromsubjectivesymptoms.

As part of a possible broadening of the criteria for endodontic success, anincreasedinterestintoothsurvivalstudieshasbeenseeninthepastfewyears.Forexample, for treatmentsrepresentinggeneraldentistry inScandinavia, thesurvival rate for root-filled teeth at a 10-year follow-up was almost 90%(Kirkevangetal.2014),andthesurvivalrateafter20yearswasfoundtobe65-70%(Eckerbometal.2007,Peterssonetal.2015).Thestudiesalsoshowthatmany root-filled teeth with AP are left without re-treatment or extraction. Itmust thereforebe reasonable to assume that these teethhavenot caused anymajor problems for the patients. Only a few attempts to calculate the risk ofexacerbatingchronicAPhavebeenpublished.However,datafromPeterssonetal. (1993)andEriksenetal. (1995) indicatean incidencerateof less than5%annually,andYuetal. (2012)reportedthat the incidenceof flare-upswas6%over a 20-year observation period (although almost 50% of the teeth hadoccasionally causedmildpain).Further,noclear linkbetween thepresenceofAP in root-filled teeth and general health parameters has as yet beenestablished, and under what conditions such teeth might be left withoutintervention has still to be confirmed (Swedish Council onHealth TechnologyAssessment 2010, Cotti & Mercuro 2015). Therefore, until there is betterscientificknowledgeregardingrisksrelatedtoAPinroot-filledteeth,itmustbeargued that RCT should be performed with high quality, aiming either topreventortocureAP.

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6 CONCLUSIONS

AcontinuingeducationalprograminNTRI,usingeducatedGDPstoperformthehands-ontrainingattheclinicswas

• Sufficientforimplementinganewinnovation,suchasNTRI,andincreasingtherateofgoodqualityrootfillings

• Notsufficienttoreducetherateofpoorqualityrootfillings,despitetheactivationofprofessionalnetworks

TheimplementationofNTRIamonggeneraldentistsresultedinincreasedroot-fillingqualitythatpersistedovertime.

Thefocusgroupdiscussionsrevealedthat

• RCTwasregardedasaverycomplexanddifficultprocedure,causinghighlevelsofnegativeemotions,suchasstressandfrustration

• Manypractitionerswereoftennotabletocompleteacasewithintheallocatedeconomicresources

• Sixcategoriesofissueswerefoundastheoriginoftheproblems:the

clinicalprocedure,theequipment/materials,thecompetenceofthedentist,thetooth,thepatientandtheorganisation.

• RCTwasoftenperformedwithanoverallfeelingof“lackofcontrol”

• Inthedecisiononwhetherornottoacceptapoorqualityrootfilling,

theradiographicappearanceoftherootfillingwasnotenough.Theimagewasalwaysrelatedtothesituationinwhichthetreatmentwasperformed.Theseconsiderationswererelatedtopulpalorperiapicalhealth,riskassessmentorconsumedpersonaloreconomicresources

• Thereappearedtobelackofacoherentmicrobiologicalunderstanding

relatedtoendodonticmicrobiologyandprognosticevaluation


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7 FUTURE PERSPECTIVES

The focus groups identified a variety of perceived difficulties and stressfulsituationsrelatedtoRCT.Manydentistsexpressedanoverallfeelingof“lossofcontrol”.AlthoughthedentistsregardedRCTascomplicatedandchallengingtoperform,theyexpressedanurgetodotheirbestfortheirpatients.Thepresenceof this“urge”providesgoodprospects for further improvements inroot-fillingqualityingeneraldentalpractice.

Whatcanbedone?

Education

ThecontinuingeducationalcoursesinNTRIresultedinanimprovementinroot-filling quality. However, the focus-group interviews revealed a lack ofunderstanding of factors that are important for the outcome of RCT and asomewhat irrationalapproachtowhetherornot toacceptroot fillingsofpoorquality.

• Furthertheoreticalandpracticaleducationwiththeemphasisonunderstandinginordertobeabletoreasonaboutproblemsandfindsolutions.Forexample,howtomanagedifficultcanals,howtoadjustgutta-perchacones,howtouseanapexlocatorandsoon.

• Althoughknowledgeof“how”todothingsisimportant,theemphasisshouldalsobeplacedon“why”thingsshouldbedone.Abetterunderstandingofendodonticinfectionsmayhelppractitionersbettertounderstandtheconsequencesoftheirdecisionsduringthewholetreatmentandinthedecisionofwhetherornottoacceptapoorrootfilling.(Possiblefuturestudy)

Insight

The literature stresses the need for feedback as away of obtaining an insightinto one’s performance. There appears to be a need to open up permanentnetworkswithaviewtoinitiatingdiscussionsandassessmentsofperformance.

Scheduledregularmeetings for jointdiscussionsandevaluationsofone’sownandothers’performancecouldbeasimplewaytogiveandreceivefeedbackand

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alsoawaytoobtainaninsightintoone’sownperformance.Thecontentofthemeetings may vary, but discussions of RCT and assessments of recent rootfillingsshouldtakeplacefrequently.(Possiblefuturestudy)

Expectation

Severalpractitionersexpressedtheideathatoptimalroot-fillingqualitycanandperhaps should not be expected in general dentistry. This idea obviouslyconstitutes a starting point for a discussion of “good enough” treatment. Theidea is rarely touched upon in academic settings and is obviously difficult toresolveusingonlyscientificresearch.Nevertheless,theissueisimportant,as,ineverytreatmentsituation,decisionshavetobemadeaboutwhethertostopandaccept the obtained result or to continue the interventions. Dentistry shouldbenefitfromanextensivediscussionofa“goodenough”conceptinvolvingbothacademiciansandgeneralpractitioners.

Theorganisation

For many dentists, economics induced different kinds of stress – either timepressure to complete a casewithin the time limit ordue to lower incomeperhour.Althoughtheeconomicstressfactorwasobvious,notalldentiststhoughtthat increased fees would solve the problem. They thought it was expensiveenoughforthepatients.

Duetothelimitedtime,therewasnotimeforreflectionontheirownpractice.Further,manypractitionerswantedtochangetofaster,easierinstrumentationsystems, but they were not able to influence the purchase. The dentists alsoaskedformagnificationequipmentsuchas andmicroscopes.

• Itwouldbedesirableatorganisationalleveltoallocateresourcesfor:o Morecontinuingeducationinendodontology(whichcould

makethetreatmentmorerationalandlesstime-consuming)o Creatinganenvironmentthatstimulatesreflectionand

professionalexchangeo GreaterinfluencefortheGDPsonpurchases,suchassimpler

instrumentationsystemsandappropriateroot-fillingsystems,whichcouldenhancethetreatmentandalsobeawaytoshortenthetimeneededforRCT

o Improvedvisualcontrol,suchasloupes(preferablywithlight)and/ormicroscopes

loupes


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ACKNOWLEDGEMENTS

I would like to expressmy gratitude to everyonewho has supportedme andcontributedinanywaytomakeitpossibletoformetocompletethisthesis.

InparticularIwanttothank:

ClaesReit,mymainsupervisorandco-author,forintroducingmetotheworldofendodontologyandresearch,foryoursupportandencouragementduringalltheseyears. Thankyouforsharingyour intellectualbrilliancewithme.Thankyou for your generosity, your patience and your time. Thank you for all theinteresting discussions about the joys and sorrows in the world outsideresearch.

Anders Molander, my co-supervisor and co-author, for introducing me toendodontology and research, for supportingme and teachingme all practicalmanagements at the start and for your guidance among figures, diagramsandtables.

HansRystedtandOskarLindwall, co-authors fromtheFacultyofEducation,for contributing with your excellent reflections and expertise. CollaborationbetweenFacultiesisenrichinginmanyways.

CharlotteUlin,headoftheSpecialistClinicofEndodontology,foryourinterest,encouragement and support. Thank you for always believing in me andarrangingthingssothatIcouldcompletethisthesis.Thankyouforwaitingforme.Iwillsoonbeback.

Thomas Kvist, for your interest and encouragement. Thank you for yourattentionwhen I needed it. Youhave supportedmy inmanyways. I ammostgrateful.

Thestaffat theSpecialistClinicofEndodontologyandMonicaBengtsson,foryourhelp,supportandunderstandingduringalltheseyears.

Allparticipatingdentists inthe formerGothenburgandSödraÄlvsborgDHS,foryourcontributionandengagement.Thankyouforsharingyourexperienceswithme.

BibiBexeliusandEvaFrantzichforappreciatedadministrativeassistance.

41

EvaWolf, for reviewing thequestion route. Your cooperation and feedback ishighlyvalued.

Amir-AliSayrafiforvaluablehelpwiththetranslationofthequotations.

Lastbutcertainlynotleast,

ÅsaEdeland,mydearestfriend,forbeingwhoyouare,foralwaysbeingthere,foryourneverendingencouragement,foryourinterestandallyourcare!

MymotherIva,foralwaysbelievinginme,forbeingsointerestedinmyresearch,myprogressandhowIam.Thankyouforbeingsokindandhelpful,foryournevereverendingenergy.Itisbecauseofyouourgardenhassurvivedthisthesis.Youarefantastic!

MydaughtersLisaandAgnes,foralwaysremindingmeoftherealworld,whatlifeisallabout.Thankyouforallthehappinessandjoyyoubring.Thankyouformakingmylifesucharichone.ILY

MyhusbandMikael, foralwaysbeingbymyside.Thankyouforyourpatients,your care and your endless love. Thank you for pushingme out into the realworld,ourworld.Thankyouformakingmylifesuchahappyone.ILY

Thisthesiswassupportedby:

• Wilhelm&MartinaLundgrensFoundationforOdontologicalResearch• PublicDentalService,RegionVästraGötaland


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APPENDIX 1: THE QUESTION ROUTE

Introductoryquestion

1. Pleasetelluswhatitwasliketoassesstheradiographsyouweregiven.

Transitionquestion

2. Presentationoftheindividualfocusgroup’sassessmentsofthe37rootfillings• Whatisyourgeneralreactiontotheresults?

Keyquestions 3. Discussionoftheselectedcases• Pleasedescribetherootfillingindetail.• Pleasetellushowyouassesstherootfillingquality

andhowyouwouldmonitorthecase.Pleasejustifythegroundsonwhichyoubaseyourdecision.

4. In-depthdiscussionoftheconceptsexpressedbytheGDPs

whendescribingtherootfillings• Whyisthe……important?

5. Pleasethinkbacktoanoccasiononwhichyoufelt

dissatisfiedwitharootfillingbutchosetoacceptit(notduetobrokeninstruments).Pleasetellus• aboutthecase• whyyoufeltdispleased• onwhatgroundsyouchosenottore-doit

6. InwhatothersituationsisitOKtoacceptadefective

rootfilling?

7. Whydoyouthinkotherdentistsacceptnewrootfillingsdespiteradiographicsignsofdefectivequality?(Text related to ”other dentists”was not included in theanalysis)

8. Pleasethinkfreelyaboutrootcanaltreatment.• Describethestepsyouconsidertobethemost

difficult.Endingquestion

9. Supposeyouweregiven“freehands”andfreeresourcestoimprovethequalityofrootfillings,inyourpracticeoringeneral.Whatwouldyoudo?Feelfreetospeculate.

Summary Summaryofthefocusgroupdiscussion.

• Isthisanadequatesummary?

on root filling quality in general dental practice...european journal of dental education 19 (2015):...

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