Is menopause associated with an increased risk of tooth loss in patients with periodontitis?

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Revista Portuguesa de Estomatologia, Medicina Dentária e Cirurgia Maxilofacial

ww w . e l s e v i e r . p t / s p e m d

Research

Is menopause associated with an increased risk of tooth loss in patients with periodontitis?

Ricardo Castro Alves

^a,^∗

, Sérgio Antunes Félix

^a

, Alberto Rodriguez Archilla

^b

aCentroInterdisciplinardeInvestigac¸ãoEgasMoniz,InstitutoSuperiordeCiênciasdaSaúdeEgasMoniz,Portugal

bFacultaddeOdontologia,UniversidaddeGranada,Spain

a r t i c l e i n f o

Articlehistory:

Received16June2013 Accepted24September2013 Availableonline24November2013

Keywords:

Menopause Oestrogen Osteoporosis Periodontaldisease Toothloss

a bs t r a c t

Aim:Toanalysethepotentialeffectsofmenopauseontoothlossinwomenwithchronic periodontitis.

Methods:Thestudyincluded102womenbetween35and80yearsoldwithchronicperiodon- titisandatleastsixteethdividedintotwogroups:thestudygroup(SG),whichconsistedof 68menopausalwomen,andthecontrolgroup(CG),whichconsistedof34pre-menopausal women.Eachparticipantwasgivenasurveytocollectseveraldemographicdatapoints,gen- eralandoralclinicalhistories,gynaecologicalhistoryandbehaviouralhabits.Severaloral andperiodontalmeasurementswererecorded,includingthenumberofteeth,plaqueindex, presenceofcalculus,probingdepth,bleedingonprobing,gingivalrecessionandattachment loss.Thefollowingstatisticaltestswereused:Chi-square,Fisher,t-testforindependent samples,Wilcoxon–Mann–Whitneynon-parametrictestandANCOVA.

Results:Atleastonetoothwasmissingin98%ofthewomeninthestudy.TheSGexhibited significantlyfewerteeththantheCG(SG10.83±5.90,CG6.79±4.66),butthedifferencewas notsignificantafteradjustingforage(p<0.05).Ontheotherhand,significantdifference wasnotobservedbetweenthegroupsforthemajorperiodontalmeasurementstaken.

Conclusions:Menopause did not appear to significantly affect tooth loss in the study population.Theeffectofmenopauseislikelysmallcomparedwithotherclinicalandsocio- economicfactors.

Estaráamenopausaassociadaaumriscoacrescidodeperdadentária emdoentescomperiodontite?

Palavras-chave:

Menopausa Estrogénio Osteoporose Doenc¸aperiodontal Perdadentária

r e su m o

Objetivos:Analisaropossívelefeitodamenopausasobreaperdadentáriaemmulherescom periodontitecrónica.

Métodos:Centoeduasmulheresentreos35-80anoscomperiodontitecrónicaepelomenos 6dentesforamdivididasem2grupos:grupodeestudo(GE)constituídopor68mulheres namenopausaegrupocontrolo(GC)constituídopor34mulherespré-menopáusicas.Foi aplicadoumquestionárioondeserecolheramdiversosdadossociodemográficos,história

∗ Correspondingauthor.

E-mailaddress:[email protected](R.CastroAlves).

http://dx.doi.org/10.1016/j.rpemd.2013.09.005

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clínicageraleoral,antecedentesginecológicosehábitos.Adicionalmente,foramavaliados diversosparâmetrosoraiseperiodontaisincluindo:número dedentes,índicede placa, presenc¸adetártaro,profundidadedesondagem,hemorragiaàsondagem,recessãogengival eperdadeinserc¸ão.NaanáliseestatísticaforamutilizadosostestesdeChi-Quadrado,Fisher, teste-tparaamostrasindependentes,testenão-paramétricodeWilcoxon-Mann-Whitneye ANCOVA.

Resultados: Noventae oitopor centodasmulheres estudadasapresentampelo menos umdenteausente.Aocompararogrupodemulherespréepós-menopáusicas,onúmero dedentesésignificativamentemenornasmulheresnamenopausa(GE10,83±5,90;GC 6,79±4,66),noentanto,depoisdeajustadooefeitodaidadeestadiferençadeixadeseresta- tisticamentesignificativa(p<0,05).Poroutrolado,nãoseobservamdiferençassignificativas entreos2gruposemrelaçãoaosprincipaisparâmetrosperiodontaisavaliados.

Conclusões: Napopulac¸ãoestudadaamenopausanãopareceinfluenciarsignificativamente aperdadentária.Comparativamenteaoutrosfatoressocioeconómicoseclínicos,oefeito namenopausanadoenc¸aperiodontalseráprovavelmentereduzido.

Introduction

After menopause, oestrogen production decreases significantly, whichis thoughtto bethe majorcause ofprimary osteoporosis.^1,2 Reduced bonedensity in the jaws may be linked to increased risk of tooth loss in individuals with- out periodontal disease or increased disease severity in individuals withperiodontitis.³ The potentiallink between osteoporosisand periodontal disease has generatedsignif- icant interestbecause these twodisease share severalrisk factorsinadditiontoboneloss.

Several studies have shown a connection between decreasedskeletalbonemineraldensity(BMD)anddecreased numbersofteeth,^4–9whileotherstudieshavenotshownthis relationship.^10–13Studiesanalysingtherelationshipbetween decreasedsystemicBMDandperiodontaldiseaseprogression havealsofoundcontradictingresults.5,9,11,13–15Inadditionto theeffectsonbone,oestrogensmayalsointerferewithother periodontal tissues(gingiva and periodontal ligament) and affecttheimmune-inflammatoryresponseofthepatient.^16–18 Improvementsinperiodontalmeasurements,^19,20 andtooth retention^21–23havealsobeenreportedinwomenundergoing hormonereplacementtherapy(HRT),althoughstudies with contradictingresultsalsoexist.^24,25

After more than 20 years, the relationship between menopause,osteopenia,osteoporosisandtoothlossremains somewhatcontroversial.

Theaimofthisstudywastoanalysethepotentialeffects ofmenopause ontooth lossbycomparing severalgeneral, oraland periodontalmeasurementsbetweentwogroupsof women(pre-andpost-menopausal)withchronicperiodonti- tis.

Materials and methods

This cross-sectional study was performed at the Instituto SuperiordeCiênciasdaSaúdeEgasMoniz(MontedaCaparica,

Portugal) with prior approval from the Institution’s Ethics Committee.

Women between 35 and 85 years old who had atleast 6teeth,hadbeendiagnosedwithchronicperiodontitisand hadnotbeentreatedduringthelastyearwereselectedfrom patientsreferredforperiodontalevaluation.Womenwithin any ofthe followingcategories wereexcluded: diagnosisof aggressiveperiodontitis,refusaltosigntheinformedconsent form, current participationinanother study or incomplete surveyorperiodontalexam.

Of the 111 women chosen to participate in the study, eight did not meet the inclusion criteria, and one declined toparticipate,which resultedinafinalsampleof 102patients.Thepatientsweredividedintotwogroupsbased ontheirmenopausalstate:astudygroup(SG)consistingof 68postmenopausalwomenandacontrolgroup(CG)with34 premenopausalwomen.

Awomanwasconsideredtobeinmenopauseifhadnot menstruatedformorethanoneyearorhadhadahysterec- tomyorbilateraloophorectomy.²⁶

Thecriteriadefinedbytheperiodontaldiseasesurveillance workgroupattheCentersforDiseaseControlandPreventionwere usedtodiagnoseperiodontaldisease.²⁷

A survey consisting of 48 questions covering several areas (personal, socioeconomic, medical history, current medication, habits and lifestyle, dental history and oral hygieneroutines)wasadministeredtoalloftheparticipants.

Thegynaecological history wasalsorecorded todetermine hormonal exposure levels (age of menarche, number of pregnancies, number ofbirths,age ofmenopause andoral contraceptiveorhormonereplacementuseforlongerthan6 months).

Alloralandperiodontalmeasurementswereperformedby asingleexaminer(R.C.A.)whowasblindtothedataobtained from thesurveyandthe menopausalstatus.Theexaminer wastrainedbeforethebeginningofthestudybyanexperi- encedobserveruntiltheirmeasurementsagreedmorethan 90%ofthetime.Themeasurementswereconsideredtoagree whentheywere≤1mmdifferent.Thecalibrationprocesswas

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performed15daysbeforethestudybeganusing10volunteer patients.Theintra-andinter-examinerconsistencywasmea- suredusingthemethodproposedbyBlandandAltman,²⁸and ahighlevelofconsistencywasachievedforboththeprobing depthandgingivalrecessionmeasurements.

The decayed, missing or filled (DMF) index,²⁹ and the presenceoffixedorremovableprostheseswasrecorded.All theteeththatwerecompletelyerupted,excludingthethird molars, retained rootsand implants,were included inthe analysis.Theexam beganwithanalysis ofthe presenceof supragingivalcalculus(absent/present)andcalculationofthe SimplifiedPlaqueIndex.³⁰

Probingdepth(PD),definedasthedistanceinmillimetres from the gingival marginto the bottomofthe pocketwas measuredatsixlocationspertoothusingaCP-12graduated periodontal probe (Hu-Friedy^®, Chicago, IL, USA). Simulta- neously, the locations that bled after probing (BOP) were recorded.Gingival recession (REC),defined as the distance fromthecementoenameljunctiontothegingivalmarginwas alsomeasuredatsixlocationspertooth.ThesumofthePD andRECvalueswasusedtocalculatetheclinicalattachment loss(CAL)ateachlocation.Themobilityofalltheteethand thepresenceoffurcationdefectsinthemolarswerealsodeter- mined.

Adescriptivestatisticalanalysiswasperformedusingall the variables including the averages, standard deviations, intervalsandpercentages.

For qualitativevariables (nominal and ordinal),the Chi- square and Fisher tests were used. Quantitative variables (discrete or continual) were analysed using the non- parametricWilcoxon–Mann–Whitneytestorunpairedt-test.

Covarianceanalysis(ANCOVA)wasperformedfortoothlossto controltheeffectofpotentialconfoundingvariables(plaque index,tobaccoconsumptionandage).

StatisticalanalyseswereperformedusingSPSS^®version17 (SPSSInc.,Chicago,IL,USA).Asignificancelevelof˛=0.05was establishedforalltests(p<0.05).

Results

Thegeneralcharacteristicsofthestudypopulationaresumm- arisedinTable1.ThemajorityofthewomenwereCaucasian (92.2%) and, as expected, the average age of the SG was significantly higher (p<0.001) than the CG (61.15±8.01 vs.

44.79±5.23).

Themost commonlyused medications for osteoporosis treatment(limitedtocurrentusebythestudygroup)werebis- phosphonates(11.74%),followedbyHRT(4.41%).Whenpast HRTuseisincludedintheanalysis,thepercentageofusers increasesto26.47%.Only4women(5.88%)usedcalciumsup- plements,andnowomenusedvitaminDsupplements.

Althoughthebodymassindexwasnotsignificantlydiffer- entbetweenthegroups,thelargemajorityofwomeninthe studywereoverweightorobese(SG70.6%;CG52.9%).

Almost two times more smokers or ex-smokers were assignedtotheCGcomparedwiththeSG(SG27.9%;CG61.8%).

Inaddition,wefoundthatthenumberofpacks/yearwassig- nificantly higher in the CG (SG 3.02±8.25; CG 7.45±10.73, p<0.001).

Analysisofthehormonalhistory(Table2)showsthatthe age of menarche was similar between the two groups (SG 12.81yearsofage;CG12.34yearsofage).Theaverageageof menopausewas49.34±5.57yearsold,and83.8%ofthecases occurrednaturally.

Thenumberofpregnancies,birthsandoralcontraceptive usewerenotdifferentbetweenthepre-andpost-menopausal women.Althoughtheresultwasnotstatisticallysignificant, womeninthestudygroupusedoralcontraceptivesforfewer yearsandhadmorereproductiveyearsduetotheirhigherage.

Thepercentageofrestoredordecayedteethwassimilar betweenthegroups,andthenumberofdentalvisitsandtypes ofpreviousperiodontaltreatmentswerealsonotsignificantly different(Table3).

The SG exhibited fewer teeth compared with the CG (p<0.01),butthereasonfortoothlosswasthesameinboth groups(Table4).Althoughthedifferencewasnotstatistically significant,thenumberofteethlostforperiodontalreasons wasslightlyhigherintheSG.

Bacterialplaqueaccumulationisstronglycorrelatedwith periodontaldiseaseanddentalcaries,andthesetwodiseases arethemajorcausesoftoothloss.Totesttheeffectsofthe covariatesplaque level, tobacco smoking andage on tooth loss, a covariance analysiswas performed. Thenumber of missingteethwasinfluencedbythemenopausalstateeven afteradjustingforplaquelevel(F_Snedecor(1)=15.83, p<0.001) and tobacco smoking (F_Snedecor(1)=10.39,p<0.01). However, aftercontrollingforage,thetoothlosswasnotsignificantly differentbetweenthegroups(F_Snedecor(1)=0.31,ns).

TheperiodontalmeasurementsareshowninTable5.The amountofbacterialplaquewashigherintheCG(p<0.01)in contrasttothenumberofsextantswithcalculus,whichwas similarbetweenthegroups.Asignificantdifferencewasnot observedbetweenthegroupsforthemajorperiodontalmea- surementstakenexceptforahigherpercentageoflocations withPD>4mmintheCG(p<0.05).

Discussion

Someauthorshavesuggestedthattoothlosswithageisdue toalveolarbonelosscausedbysystemicbonelossandtolocal factors(periodontaldisease).

Tooth lossmay belinkedtooverall healthdeterioration throughchangesineatinghabits.^31,32However,thebodymass index ofthe populationstudiedwas high despitethe high numberofmissingteeth,suggestingthatthisrelationshipis notlinear.

Mostofthewomeninthestudypopulationhadatleastone missingtooth,andthenumberofmissingteethwashigher intheSG(10.83±5.90vs.6.79±4.66;p<0.01).Theprevalence ofdentalcariesandthedifferencesintheperiodontalmea- surementsbetweenthetwogroupsdonotfullyexplainthe discrepancyinthenumberofmissingteeth.Usingtoothloss as a surrogate measureof periodontal disease has several limitations.³³Thenumberofteethisanindicatorofthecumu- lativeeffectsoforalhealthconditionsovertime.⁴Inaddition, tooth loss is a complex phenomenon that is likely linked tovariousfactorsincludinggenetics,nutrition,oralhygiene, healthcareaccessandtobacco smoking.Afteradjustingfor

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Table1–Generalcharacteristicsofthestudypopulation(n=102).

Studygroup (n=68)

Controlgroup (n=34)

p-Value

Age(average±SD) 61.15(8.01) 44.79(5.23) t(92.9)=12.37;

p<0.001 Nationalityn(%)

Portuguese 61(89.7%) 28(82.4%) F,ns

Other 7(10.3%) 6(17.6%)

Educationleveln(%)

Elementary 51(75.0%) 13(38.2%)

Secondary 9(13.2%) 13(38.2%) X²(1)=13.45;

p<0.001

Higher 8(11.8%) 8(23.5%)

Racen(%)

Caucasian 63(92.6%) 31(91.2%) F,ns

Black 5(7.4%) 3(8.8%)

Numofsystemicdiseases(average±SD) 1.54(1.11) 0.65(0.65) U=597.5;W=1192.5;

p<0.001

Numofmedicationstaken(average±SD) 2.76(2.52) 0.76(0.89) U=504.0;W=1099.0;

p<0.001

BMI(average±SD) 27.78(5.43) 26.15(4.92) U=954.0;W=1549.0;

ns Tobaccoconsumptionn(%)

Never 49(72.1%) 13(38.2%) X²(1)=10.88;

p<0.01

Smokersorformersmokers 19(27.9%) 21(61.8%)

Alcoholconsumptionn(%)

Never 14(20.6%) 8(23.5%) X²(1)=0.12;ns

CurrentorPrevious 54(79.4%) 26(76.5%)

Regularphysicalexercisen(%) 44(64.7%) 24(70.6%) X²(1)=0.35;ns

Atleast1dentalvisitinthelastyearn(%) 16(23.5%) 12(35.3%) X²(1)=1.58;ns

BMI,bodymassindex;F,Fishertest;ns,notsignificant;t,unpairedt-test;U,W,non-parametricWilcoxon–Mann–Whitneytest;X²,Chi-square test.

Table2–Hormonalhistory.

Studygroup (n=68)

Controlgroup (n=34)

p-Value

Ageofmenarche(average±SD) 12.81±1.61 12.34±1.70 U=858.0;W=1386.0;

ns

Ageofmenopause(average±SD) 49.34±5.57 – –

Num.ofpregnancies(average±SD) 2.65±1.84 2.44±2.36 U=979.5;W=1574.5;

ns

Num.ofbirths(average±SD) 1.79±1.22 1.71±1.06 U=1133.5;

W=1728.5;ns OralcontraceptiveuseYearsused(average±SD) 9.25±10.23 10.57±10.97 U=927.5;W=3205.5;

ns

Reproductiveyears(average±SD) 36.67±5.83 33.18±5.83 t(99)=2.85;p<0.01

Yearsofoestrogenexposure(average±SD) 37.76±6.02 9.01±10.80 U=28.5;W=623.5;

p<0.001 Typeofmenopausen(%)

Physiological 57(83.8%) – –

Surgical 11(16.2%)

Menopausalsymptomsn(%) 60(89.6%) – –

HRTusersn(%) 18(26.5%) – –

YearsofHRTuse(average±SD) 1.87±2.93 – –

AdverseeffectsfromHRTn(%) 2(11.1%) – –

ns,notsignificant;t,unpairedt-test;U,W,non-parametricWilcoxon–Mann–Whitneytest.

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Table3–Oralparametersanddentalhygieneroutines.

Studygroup (n=68)

Controlgroup (n=34)

p-Value

DMFindex(average±SD) 17.84(6.90) 16.68(5.48) t(100)=0.86;Fns

Removableprosthesisn(%) 31(45.6%) 8(23.5%) X²(1)=4.67p<0.05

Fixedprosthesisn(%) 1(1.5%) 3(8.8%) Fns

Lastdentalvisitn(%)

≤1year 16(23.5%) 12(35.3%) Fns

>1year 52(76.5%) 22(64.7%)

Previousperiodontaltreatmentn(%)

None 43(63.2%) 21(61.8%) Fns

Dentalprophylaxis 19(27.9%) 12(35.3%) Fns

Scalingandrootplanning – – –

Periodontalsurgery 1(1.5%) 0(0%) Fns

Several 18(26.5%) 4(11.8%) Fns

Brushingn(%)

Onceperday 14(20.6%) 7(20.6%) Fns

Morethanonceperday 54(79.4%) 27(79.4%)

Flossn(%)

Never/occasionally 61(89.7%) 26(76.5%) Fns

Oneormoretimesperday 7(10.3%) 8(23.5%)

Mouthwashn(%)

Never/occasionally 38(55.9%) 15(44.1%) Fns

Oneormoretimesperday 30(44.1%) 19(55.9%)

DMF,decayedmissingfilledindex;F,Fishertest;ns,notsignificant;t,unpairedt-test;X²,Chi-square.

Table4–Comparisonofthenumberofteethinpre-menopausalandpost-menopausalwomen.

Studygroup (n=68)

Controlgroup (n=34)

p-Value

Numberofwomenwithmissingteethn(%) 66(97.1%) 34(100%) Fns

Numberofmissingteeth(average±SD) 10.83±5.90 6.79±4.66 U=710.5;W=1035.5;p<0.01 Reasonforlossn(%)

Periodontal 10(14.7%) 2(5.9%) Fns

Decay 33(48.5%) 20(58.8%) Fns

Fracture 3(4.4%) 10(29%) Fns

Several 21(30.9%) 10(30.9%) Fns

Unknown 1(1.5%) 1(2.9%) Fns

F,Fishertest;ns,notsignificant;U,W,non-parametricWilcoxon–Mann–Whitneytest.

Table5–Distributionofperiodontalvariablesinpre-andpost-menopausalwomen.

Studygroup (average±SD)

Controlgroup (average±SD)

p-Value

Plaqueindex(PI) 40.08±20.24 51.41±20.69 U=770.5;W=3116.5;

p<0.01

Num.ofsextantswithcalculus 2.38±2.25 2.97±2.59 U=1038.0;

W=3384.0;ns

Lossofattachment(CAL) 4.31±1.08 4.05±1.28 t(100)=1.09;ns

Probingdepth(PD) 3.25±1.70 3.25±0.69 U=1144.0;

W=3490.0;ns

Gingivalrecession(REC) 1.06±0.81 0.78±0.70 U=875.5;

W=1470.5,0;ns Num.oflocationswithbleedingonprobing(BOP) 37.75±22.19 38.48±22.76 t(100)=−0.16;ns

Toothmobility 0.89±0.59 0.75±0.56 U=1124.5;

W=1719.5;ns

Furcationlesions^a 0.22±0.58 0.17±0.43 U=1128.0;

W=1723.0;ns

a Onlyformolars;F,Fishertest;ns,notsignificant;t,unpairedt-test;U,W,non-parametricWilcoxon–Mann–Whitneytest.

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theeffectsofage,wefoundthatthenumberofmissingteeth wasindependentofmenopausalstate.

Unlike us, Musacchioet al. observedthat ageing, years sincemenopause (>23), number ofchildren(>3) and social isolationareindependentriskfactorsfortooth loss.³⁴ Sub- sequently, Meisel et al. also found an inverse relationship betweenthe number ofteethand the numberofchildren, butthedifferenceofapproximatelyonetoothperchildonly appliedtosocioeconomically poorwomenthatdidnotuse HRT.³⁵

Bollenetal.showedthatageandtobaccosmokinggreatly affectedthenumberofteethinanelderlypopulationincon- trast toa history of osteoporoticfractures.³⁶ On the other hand,Nicopoulou-Karayiannietal.showedthatwomenwith osteoporosishavefewerteeththanthosewithosteopeniaor withanormalBMDevenafteradjustingfortobaccoconsump- tionandage.⁸

Similarly, Inagaki et al. found a correlation between decreasedBMDandfewerteethonlyinwomenwithanaver- age age of63. According tothese authors, this fact is not surprisingbecausetheyhadbeenexposedtothepossibledele- teriouseffectsofosteoporosisforlongerperiodsoftime.³⁷

Inyoungwomen,Earnshawetal.concludedthattoothloss dependsmoreondietaryhabitsandprevioustreatmentsthan onbonelosswithage.¹⁰

However,incertainpopulations,toothlossisinextricably connectedwitheconomicissuesanddentaltreatmentdeci- sions.Someteetharealsoextractedforreasonsunrelatedto disease(orthodonticorprostheticreasons,forexample).

Although some authors have suggested that tooth loss couldbeusedasanindicatorfordecreasedBMDandtodecide whocouldbenefitfromadensitometrytest,othersconsider that usingtooth loss alone asa screeningtoolis notvery precise.³⁷

The limitations of this study include the fact that the measurements for bone density or height were not taken andthatmenopausalstateandHRTusewerebasedonself- reporting.However,self-reportingcontinuestobewidelyused inepidemiologicalstudiesbecausemeasuringhormonelev- elsistime-consumingandexpensive.Furthermore,asingle measurementofhormonelevelscannotshowtheoestrogen exposureoveralifetime.Severalstudieshavefoundahigh degreeofconcordancebetweenself-reporteddataonHRTuse andmedicalrecords.²²

It is possible that the methodology used in this study recruitedpeoplewhoweremoreconcernedwiththeirhealth andhadmoreaccesstomedicalcare.Becausethestudypop- ulationisnotrepresentativeofthePortuguesepopulation,the datashown herecannot beextrapolatedto thepopulation ingeneral.Therefore,additionalstudieswithlargersample sizesandlongerobservationtimesareneededtoconfirmthis hypothesis.

Conclusions

Menopausalwomenhave fewerteeththan premenopausal women, but the reasons for the teeth loss are similar in bothgroups.Afteradjustingforage,thenumberofmissing teethwas not affected bymenopausal state. Theeffect of

menopauseislikelysmallcomparedwithotherclinicaland socioeconomicfactors.

Ethical disclosures

Protection of human and animal subjects.The authors declarethattheproceduresfollowedwereinaccordancewith the regulations ofthe responsible Clinical Research Ethics CommitteeandinaccordancewiththoseoftheWorldMedical AssociationandtheHelsinkiDeclaration.

Confidentiality of data.Theauthors declarethat theyhave followed theprotocols oftheir workcentre onthepublica- tionofpatientdataandthatallthepatientsincludedinthe study have received sufficientinformation and have given theirinformedconsentinwritingtoparticipateinthatstudy.

Right to privacy and informed consent.The authors must haveobtainedtheinformed consentofthe patientsand/or subjectsmentionedinthearticle.Theauthorforcorrespon- dencemustbeinpossessionofthisdocument.

Conflicts of interest

Theauthorshavenoconflictsofinteresttodeclare.

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