Biocompatibility of Dental Materials Flashcards
Three uses for Methacrylate materials in dentistry and medicine.
- dental composite
- bone cement
- adhesives
What are the common monomers used for methacrylate materials?
MMA BisGMA TEGDMA BisEMA HEMA
(…or blah, blah, blah, blah)
________ - the ability of a material to function in a specific application in the presence of appropriate host response
biocompatibility
True or False: Biocompatibility means inert to the body.
False, that was previously desired but now we want a POSITIVE interaction, not inert
What are the classifications of various tissue reactions (3)?
none (bioinert)
positive
negative
True or False: Reactions can take years to manifest and are difficult to detect.
True
Multiple exposures result in huge _____.
permutations
What are three examples of positive interactions?
promote healing
integration with tissue
restoration of function
What are five examples of negative interactions?
tissue necrosis allergic reaction immune reaction systemic toxicity mutagenicity
Materials function in 1 of 5 ways. What are the five functionalities?
- functional
- restorative/structural
- esthetic
- drug delivery
- scaffolding/tissue engineering
(FRED’S 5 ways)
Which agencies set standards for regulatory compliance?
FDA
EU (European Union?)
ISO/ADA
How is a material’s biocompatibility determined?
cell culture
animal testing
clinical testing
True or False: Cell culture tests are lower cost.
True
True or False: Cell culture tests can model in vivo resposes of a material
True
To detect a 0.1% incident rate, how many patients are needed?
4000
Cell culture tests measure _____ interactions.
specific (particular cell lines are used)
True or False: Cell cultures allow for large, quick screenings.
True
What is a major downfall for cell cultures?
only testing one cell line, difficult to model immune response or long term effects
Which type of cell culture is better at modeling in vivo conditions?
primary cell cultures
permanent are less variable
______ is determined by measuring cell viability in the presence of a given material.
cytotoxicity
The cell number and growth test observes cell _____ as a function of _____ to the material.
density
proximity
The MTT Test measures the activity of ____ in the cell.
an enzyme
- MTT (yellow) added
- Cell reduces MTT to Formazan (blue color)
- measure Formazan by UV-vis
- high concentration of Formazan = high cell action
True or False: The Alamar Blue Test is a destructive measure of cell metabolism.
False, non-destructive
True or False: Metabolic tests are an indirect measure of cell viability.
True, resting cells don’t show activity and few cells of high or low activity can skew results as a whole
What is “splat deposition” and what is it used for?
injected powder particles are melted into plasma and impact substrate at high velocity
used for HA coating on implants
True or False: Splat deposition results in incomplete coalescence of particular regions
True, gives the surface high texture (some say porosity)
True or False: Surface roughness improves integration.
True
True or False: Thick calcium phosphate appears to have a detrimental effect.
False, is not detrimental, but thin calcium phosphate appears to have a benefit over thick
True or False: The most significant issue with metal alloys is leaching of ions from corroding metal.
True, but it is not a systemic concern
What is estrogenicity?
the concept that certain chemicals can act as estrogen or other hormones and will disrupt the endocrine system
True or False: TEGMA and HEMA can cause apoptosis.
True!
the pathway is uncertain and it is concentration dependent
A possible mechanism for TEGMA/HEMA caused apoptosis is the increase in _____.
Reactive Oxygen Species (ROS)
True or False: Composites, Polymer Surfaces, and Leached Monomers can influence growth and regulation of bacteria and fungus.
True
Hydro_____ monomers inhibit bacterial growth.
phobic
Which monomers leach at a greater rate and cause bacterial growth? (hydrophilic vs hydrophobic)
hydrophilic
In the study of curing levels compared to bacterial colonization, the results showed…?
higher curing power (800) and longer cure time (80s) resulted in lower bacteria density
