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Volume2 Issue8
S
upporting
Y
our
P
ractice
Twobasicdesigns exist for afixedprosthesis that joins anatural tooth toan implant:
1. fixedpartial dentures (bridge)
2. fixedpartial dentureswithanon-rigidconnector (bridgewitha semi-precision
attachment)
Implant assessment
Tobe successful, osseointegrated implantsmust exhibit:
– Function: ability tochew
– Good tissuephysiology: absenceof pathophysiology/pain, integrationwith the
boneandahealthyperiodontium
– Patient satisfaction: esthetics andnodiscomfort
Mobilityassessment of natural teeth
Themobilityof thenatural teethmust beassessedas it influences thedecision to join
the implant andnatural teethmore thananyother factor.
When implants areconnected tonatural teeth, theprosthesismust bedesigned such
that the initial contact and load is applied to thenatural toothandnot the implant.
Natural teethare supportedbyahealthyperiodontal ligament and thus, havenatural
healthymovement associatedwith them. Somemobility innatural teeth is expected
andwithinnormal limits. Incontrast, implantshaveabone-implant interface,which is
rigid.
Any lateral forcesmust beminimizedas they increase toothmovement andmay
damage the implant-bone interface. Shear (lateral) forces arecreatedat thebone-
implant interfaceandbone is 60%weakerwith lateral loads. Additionally, screw-
looseningand/or thecement-seal strength is compromisedwith lateral loading. The
shear forces also increase the stress at the level of thecrestal bone.
Whenan implant is connected toanatural toothwithafixedprosthesis in thedynamic
oral environment, there is an increased risk to the longevityand stabilityof both
Doyouhaveanyburningclinicalquestions related toyoureverydaypractice?Areyou facingachallenging
clinicalcaseandneedadvice?Sendyourqueries toOasisDiscussions forexpertguidance.The following
questionwassubmitted toOasisDiscussionsbyageneraldentist.Drs.NatalieWongandSuhamAlexander
provideda response.
Question
Response
There isevidence toboth
supportanddiscredit linking
aprosthesis toanatural
toothand implantabut-
ment.Detailed information
andclinical findingsmust
thereforebeconsideredbe-
foreestablishinga treatment
plan.
When is it appropriate to link a prosthesis to natural teeth and implants?
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