Introduction Articulators and Facebows Flashcards
TYPES OF RESTORATIVE MATERIALS FOR TEETH (5)
dental amalgam composite materials gold restorations (gold foil) gold castings (inlays, onlays, crowns) ceramics
ceramics includes (3)
crowns
bridges (fixed partial dentures)
veneers
CONCERNS ABOUT DENTAL AMALGAM AS RESTORATIVE MATERIAL (8)
poor aesthetics compared to resin composites
weakening of tooth from removal of tooth structure
recurrent caries
no adhesive bonding unless bonded restoration
sensitivity of properties to manipulation
brittle nature of material
biocompatibility (not generally considered problem for patients)
wastewater pollution with mercury
CONCERNS ABOUT DENTAL AMALGAM AS RESTORATIVE MATERIAL (8)
poor aesthetics compared to resin composites
weakening of tooth from removal of tooth structure
recurrent caries
no adhesive bonding unless bonded restoration
sensitivity of properties to manipulation
brittle nature of material
biocompatibility (not generally considered problem for patients)
wastewater pollution with mercury
downside of dental amalgam restorations (2)
upside (1)
mercury
not aesthetically pleasing
repairs itself over time
dental composite advantages (5)
aesthetics bonding to tooth structure can be more conservative in the preparation of the tooth less expensive than ceramic reduced mercury
dental composite disadvantages (6)
shrinkage
durability
chipping
more skill and training required
need to keep working area in mouth completely dry
time and expenses (20 more min longer per restoration)
bonding allows the dentist to use dental composites on teeth to change (3)
shape, color, contours
oldest type of filling material available
gold foil/direct gold
how long does gold last
can last the lifetime of the patient
— — can be placed in one visit in small cavities and will last longer than any other restorative material
pure gold
average cost of metal in a cast gold crown
250 dollars
cost of a full gold crown can be over
300 dollars
why can aesthetics be a problem?
depends on your personal concept of aesthetics
“How Long Will PFM Crowns Last?” (3)
95% success rate between 5-10 years in cross-sectional
study
97.5% success rate at 7 years
95.5% at 7 years assessed in private practices
tooth replacement options with implants (3)
complete dentures
partial dentures
fixed bridge and single teeth
skipped:
High Strength Ceramics (6)
- Broad range of indications
- • Excellent clinical performance
- • Accepted metal alternative
- • Less tooth reduction required
- • Thinner coping thicknesses
- • Shaded coping options offer improved esthetics
articulator
a mechanical device that simulates mandibular movements of condyles in their fossae
uses of the articulator (4)
diagnosis
treatment planning
communicate with patients/patient education
fabrication of protheses/restorations
components of the articulator (5)
upper member lower member anterior or incisal pin condylar mechanisms mounting ring (guide and retention system)
non adjustable or hinge articulators allow only — movements
opening and closing
non adjustable articulators can be usde for
single posterior restoration
the use of a non adjustable articulator can create a change in the — —, and by doing so the final restoration will present premature contacts
closure angle
articulator used the most
semi-adjustable
semi adjustable articulators allow for (3) movements
opening and closing movements as well as excursive lateral and protrusive movements
Types of Semi-Adjustable Articulators: (2)
arcon
non arcon
arcon (2)
- Condyles in lower member
- Condylar inclination in the upper member
non arcon (2)
Condyles on upper member
Condylar inclination on the lower member
what type of articulator is our articulator?
arcon articulator
purpose of the facebow
orient the maxillary cast to the rotational axis in three planes
using a facebow will result in reproducible articulation of the subsequent — casts
maxillary
the facebow orients the dental cast in the same relationship to the
opening axis of the articulator
usually the anatomic references are the (2)
mandibular condyles transverse horizontal axis and one other selected anterior point
kinematic locates the
true transverse horizontal axis of rotation
arbitrary locates the
axis by using anatomical landmarks
arbitrary utilizes — — to approximately locate the axis of rotation
average measurements
transverse horizontal axis (terminal hinge axis)
imaginary axis which passes through each of the mandibular condyles
it is around the transverse horizontal axis that the — of the mandible occurs
pure rotational movement of the mandible
the transverse horizontal axis is about – mm under the soft tissues in the front of the — (on each side of the face)
8 mm
tragus
Bergstrom point
a point 10 mm anterior to the center of a spherical insert in the external auditory meatus and 7 mm below the Frankfort horizontal plane
Ear-bow
Indexes to external auditory meatus and registers the relation of the max arch to these and a horizontal reference plane
the facebow orients the maxillary cast to a
reference plane
the reference plane requires – points
3
two on each side of the face and one on the anterior face
the anterior reference point is also known as the
3rd point of reference
the 3rd point of reference should be (2)
repeatable and reproducible
3rd point of reference (5)
orbitale nasion maxillary incisor incisal edge lower edge of the nostril parallel to the upper and lower arms of the articulator
orbitale
the lowest point on the intra orbital rim (spring bow)
nasion
whip mix
maxillary incisor incisal edge
denar
lower edge of the nostril
older hanau models
when to use a face bow (3)
cusp teeth are present
interocclusal records are made at an increased occlusal vertical dimension
the occlusal vertical dimension is subject to change and alteration in occlusal surfaces are necessary
