hello everyone and welcome to chairside live I'm your host Megan strong great show today we
have dr. Murray Sean who's back with an obsidian Presta metal case the patient in her chair had
an old failing PSM bridge so let's take a look at how she replaces the bridge utilizing the
obsidian line of restorations check it out hello and welcome to this clinical video today I have an
exciting case to share with you a great example of what I do when a large pfm bridge fractures
I replace it with an obsidian pfm it is a lithium silicate material known to achieve two times more
chip resistance than your traditional P fm's we can see he has severe crowding of the lower
incisors and a unilateral cross bite a closer look reveals chipped and cracked porcelain
inflamed gingiva in a failed class 5 composite on the upper right this old pfm spanned from 7 to 11
with pan ticks replacing left central and lateral incisors because number seven was splinted to the
rest of the bridge we can note the interdental gingivitis created by the bacteria due to the
inability of the patient to floss in between the restorations to rehabilitate this mile-high
treatment plan for obsidian veneer on number six and obsidian press to metal single crown on seven
and an obsidian press numeral four unit bridge from eight to eleven as I was cutting through
this restoration with the zoo cut bar I felt that the metal was very thick and had to switch to a
reservoir to be able to get to the material after using a double-ended crown remover I finally got
the bridge off in few pieces you can appreciate the amount of metal thickness there was on the
lingual after the bridge was removed I struggled a great deal to get this off and in the process I
nicked the underlining prep so here I am using acid etch and bonding to prepare the surface
prior to expressing ty core dual cure flowable composite material the damage is corrected and
rep is reshaped to provide more retention and resistance for the future restoration for the
venire I started the preparation with the use of a calibrated bird that will provide precise cuts of
0.3 gingival 0.5 middle and point 7 millimeter in size only then I am blending in the cut of using
a fine diamond with a 1.5 calibrated bird I am doing here an incisor reduction this calibrated
birds keep the reduction in to animo and offer correct thickness to fabricate a well-designed
obsidian veneer I found that with pre calibrated Birds I can stay into animo which is essential
for effective addition of an obsidian or any or ceramic veneers due to gingival inflammation still
present I opted to temporize and finalize the preps at the next appointment here taking up the
Provisionals one week later the excess cement was removed with Cabot Ron and teeth were cleaned with
pumice tissue was still irritated possibly because in my provisional I left some over counter margins
or I did not provide sufficient interproximal separation to prevent papaya impingement in the
end for a predictable impression I still achieve adequate tissue management with a double core
technique first I use double zero with epi then number two cord as my second cord to gain lateral
retraction because double cord displaced the tissue 0.5 millimeter gingival II I was able
to drop the margin and with a fine diamond on a slow-speed with no water I trace around and refine
the margins avoiding contact with the tissue I tried to avoid further traumatizing the soft
tissue during finish line preparation or second cord application Here I am placing a mixture of
number 1 and 3 anatomical camper caps and have the patient's bike down for about 7 minutes while my
assistant is finishing up removing the second cord I start injecting my pressure material when doing
this many units I always use a custom tray this will ensure rigidity and uniform display of the
impression material I think this is a good way to capture an accurate impression easy-to-read
that will help CAD CAM technician to create a well-fitting margin and a better emergence profile
I found transferring the color of the underlining tooth structure with the photo of selected stamp
shade in place is a great way of communicating the shade to the lab technician here is at
the delivery appointment we can appreciate the health of the soft tissue after the temporaries
were removed preparation were freed of cement and cleaned using profit cup and pumice after trying
each restoration individually to evaluate marginal fit I will try them collectively to evaluate the
proximal fit the facial surface of the veneer prep can also be clean from provisional resin
leftovers by using air abrasion for isolation I use my large strip and cotton rose and as a
looting material for the veneer I used varial ink 37 percent acid etch was applied to enamel
and dentine and allowed to react for 15 to 20 seconds one step that should not be omitted
is a to 1-minute application of glutaraldehyde agent such as g5 knowing for its antibacterial
and desensitization properties then the entire surface was coated with universal adhesive and
scrubbed in for 20 seconds then with oil moisture free air was used to displace the coat into a teen
film after the inner surface of the veneer was cleaned and salinated varial including composite
was applied onto the intaglio surface and veneer was seated with light pressure using wooden sticks
while light pressure was maintained excess cement was removed with a micro brush and briefly light
cured so excess could be easily removed with hand instruments liquid stripped was applied
to create a good marginal transition without an oxygen inhibiting layer final polymerization was
completed and then liquid stripped was rinsed off with water the proximal surfaces should be
carefully examined and if any cement residue is found should be removed to ensure perfect
fit for the other restorations the rest of the preparations are again cleaned with pumice paste
and treated with g5 before the cementation of the Obsidian press to metal restorations when there is
an area where the gingival tissue is covering the finish line I use the double zero cord to keep the
tissue away from being trapped under the cemented margin or I use it to protect the sulcus from
resin cement infiltration my choice of cement for any metal restoration is rely X looting plus it is
a resin-modified glass ionomer self curing cement that has a tack and wave light curing option
making it easy to clean up the excess because I use two different types of looting agents for
this case I opt to cement each restoration individually taking particular care during
cleanup phase to ensure proper sitting after all the leftover cement was removed occlusion
was checked for pro true Civ and lateral exclusion necessary adjustments were performed to establish
k9 guidance on the upper right side which had number six in cross bite prior to treatment
these be FM's made of obsidian lithium silicate ceramic pressed metal have great strength and
are particularly suitable where traditional pfm failed this obsidian combo restorations
enable good aesthetic results to be achieved and the patient was very happy with his new
smile without about wraps it up for this episode of chairside live on behalf of everyone here at
Glidewell laboratories we thank you for watching and I'll meet you right back here next time
you