fixed partial dentures, introduction and treatment planning Flashcards
when talking about FPD’s , what is the retainer, abutment, potic and connector?
retainer- crown, abutment- tooth, pontic-tooth form, connector- connects the pontic to abutments and is rigid or non-rigid.
explain rigid and non rigid connectors
rigid acts as a solid piece. Non-rigid acts as a key and lock and they slide into each other
what does treatment planning involve?
discussing the sequence of the treatment with the patient. The patient should sign a form accepting the plan.
a good plan should inform the patient about…….
current conditions, extent of treatment, time and cost, home care needed
why is it important to offer multiple plans?
failing to explain and present alternatives may be considered legally negligent.
what are some main points to keep in mind while creating a treatment plan?
correcting a disease, restoring function, prevention of future disease, improving appearance.
missing teeth can be replaced by 3 methods
removable partial denture, fixed partial denture, implant supported fixed partial denture.
what are factors that must be weighed when choosing the type of prosthesis?
biomedical, periodontal, esthetic, financial, patient wishes.
vital teeth are better than non-vital for abutments. Non vital can be used if…….
asymptomatic, root canal is sealed, complete obturation of canal, need some sound coronal tooth structure.
why examin the peridontium before FPD?
supporting tissues need to be healthy. Abutment teeth cannot be mobile because they carry an extra load.
roots and supporting tissues should be evaluated for 3 things
crown-root ration, root configuration, periodontal ligament area.
crown to root ratio must be…
2:3, but a minimum of 1:1 is accepted
why look at root configuration before an FPD?
wide divereged roots holdthe FPD better than skinny converged roots.
why look at rooth canal before FPD?
irregular configuration with some curvature holds better that straight roots
why look at the PDL area before FPD?
the bigger the root the bigger the surface area for PDL attachment which stabilizes the tooth
whats Antes law?
the root surface area of the abutment teeth have to be equeal or surpass that of the teeth being replaced with pontics
Bending/deflection of pontic
directly proportional with the cube of the length. Ex: a 2 toothed pontic span allows 2x2x2=8 times the bending of a single tooth pontic span
bending/deflection and pontic thickness.
its inversely proportional with the cube of the occluso-gingival thickness of the pontic. Ex: 1/2 pontic thickness–> 8 times the bending
single crowns are dislodged more easily in what direction?
Facial/lingual
FPD’s are more easily dislodged in what direction?
mesial/lingual
which tooth causes the most problems with path of insertion?
the mandibular 2nd molars because its on an angle
why is this a problem?
it will impede the retainer from seeting correctly. So orthodontic work might need to be done
proximal half crown on FPD
this only uses the proximal half of a tooth as an abutment. This is another way to avoid orthodontic work.
telescope crown FPD
basically this reduces the abutment more to allow for the retainer to sin without being impeded by the tooth behind it.
non rigid connector FPD
this allows you to seat the FPD at an angle so you could seat it without being impeded.