retention: a sensible, evidence-based approach dr … · retention: a sensible, evidence-based...

Retention:asensible,evidence-basedapproachDrSimonJLittlewood

Consultant&SpecialistOrthodontist,UK

Challengeofpreventingrelapse• Preventingrelapseisarguablythemostchallengingproblemforanyorthodontist• Aetiologyofrelapseincludesbothorthodonticfactors(periodontal@ibres/occlusalfactors)and

normalphysiologicalchangesor“aging"(growthandlong-termsofttissuechanges)1• Ifretainersarenotworn,long-termunwantedchangesafterorthodontictreatmentshouldbe

regardedasnormal,notunlucky• Long-termobservationalstudiesofpatientswhohavenothadorthodontictreatmentshow

deteriorationinthealignmentofteeth,asaresultofnaturalreductionofarchlength,reductioninarchdepthandreductioninintercaninewidth2

• Currentlythebestwayweknowtopreventrelapselong-termappearstobewearingretainerslong-term

• Thereiscurrentlyagenerallackofscienti@icevidencetosupportwhichtypeofretainerisbest3• Thislecturewilldiscusssomeofthepotentialchallengesofaskingpatientstowearretainerslong-

term,includingoralhealthissuesandcompliance

Oralhealthissuesoflong-termretainerwear• Patientswithbondedretainershavedifferentoral@lora.Thereisanintra-oralincreaseofbacteria

capableofcausingcariesandperiodontaldisease4• Fortunately,mostclinicalstudiessuggestthatprovidedgoodoralhygieneismaintained,thisdoes

notnecessarilytranslateintoactiveclinicaldisease• Thereishoweverthepotentialforseverecariesifpatientshaveahighcariogenicdiet,whilewearing

removableretainers,particularlyfullcoveragevacuum-formedretainers5• Bondedretainershavethepotentialtomoveteethintounfavourablepositionsiftheyarenotplaced

inapassiveposition,oriftheyaredistortedandbecomeactive6• Ithasbeensuggestedthatonepossiblecauseofunwantedtoothmovementasaresultofbonded

retainersmaybeduetocommonlyusedtwistedmultistrandwireswhichcouldbeunwinding7

CAD/CAMNitinolbondedretainers• Inanattempttoensureapassive,well-@ittingbondedretainer,commerciallyavailableCAD/CAM

fabricatednitinolretainersarenowavailable(Memotain®)• Theseindirectlyproducedretainersofferthepotentialforahigh-precision@it,customisedtoeach

patient.Thismaybeparticularlyusefulintheupperarch,wherepositioningiskeytominimiseocclusaltraumaanddistortion

• Thenitinolmaterialshouldallowgoodphysiologicalmovement,aswellasbeinglesslikelytobebedistortedinuse.

• ThisarelativelynewproductandafutureprospectiveRCTisplannedtoinvestigatethemfurtherandthisstudywillbediscussed.

Compliance• Compliance(betterreferredtoas“adherence”)iskeyforremovableretainers.• Factorsthataffectadherencewillbediscussed8• Amethodofsuccessfullyimprovingadherenceofremovableretainersthathasbeentestedinan

RCTwillbediscussed9

SimonJLittlewood,April2017

�

www.littlewoodortho.com

References

1. LittlewoodSJ,KandasamyS,HuangG.(2017).Retentionandrelapseinclinicalpractice.AustralianDentalJournal;62:(1Suppl):51–57

2. TsiopasN,NilnerM,BondemarkL&BjerklinK(2013).A40yearsfollow-upofdentalarchdimensionsandincisorirregularityinadults.EuropeanJournalofOrthodontics;35:230–235

3. LittlewoodSJ,MillettDT,DoubledayB,BearnDR,WorthingtonHV(2016).Retentionproceduresforstabilisingtoothpositionaftertreatmentwithorthodonticbraces.CochraneDatabaseofSystematicReviews2016,Issue1.Art.No.:CD002283.DOI:10.1002/14651858.CD002283.pub4.

4. TurkoC,BavbekNC,VarlikSK&AkcaG(2012).In@luenceofthermoplasticretainersonStreptococcusmutansandLactobacillusadhesion.AmJOrthodDentofacialOrthop;141:598-603

5. LittlewoodSJ(2012).StabilityandRetention(chapterintextbook).Orthodontic:PrinciplesandPractice(editedbyDalgitGill,PublisherWiley-Blackwell)

6. AbudiakH,SheltonA,SpencerRJ,BurnsL,LittlewoodSJ(2011).Acomplicationwithorthodontic@ixedretainers:Acasereport.OrthoUpdate;4(4):112–117.

7. KuceraJ&MarekI(2016).Unexpectedcomplicationsassociatedwithmandibular@ixedretainers:Aretrospectivestudy.AmJOrthodDentofacialOrthop;149:202-11

8. MirzakouchakiB,ShiraziS&ShiraziS(2016).AssessmentofFactorsAffectingAdolescentPatients’CompliancewithHawleyandVacuumFormedRetainers.JournalofClinicalandDiagnosticResearch.2016Jun,Vol-10(6):ZC24-ZC27

9. LinF,SunH,NiZ,ZhengM,YaoL(2015)AfeasiblemethodtoimproveadherenceofHawleyretainerinadolescentorthodonticpatients:arandomizedcontrolledtrialPatientpreferenceandadherence;9:1525-1530

�

www.littlewoodortho.com