NJXDG COMPREHENSIVE EXAM UPDATED QUESTIONS
AND SOLUTIONS RATED A+
✔✔Placing and removing gingival retraction cord (EFDA) - ✔✔Preparation
1) Rinse and gently dry the prepared tooth; isolate the quadrant w cotton rolls. Dry
tissue makes it easier to see the details of the gingival tissue and place the retraction
cord.
2) Cut a piece of retraction cord 1 to 1.5 inches in length, depending on the size and
type of tooth under preparation. The length is determined by the circumference of the
prepared tooth and the placement technique to be used.
3) Use cotton pliers to form a loose loop of the cord. This makes the cord easy to slip
over the tooth, but the loop is not tied or knotted.
Placement
4) Make a loop in the retraction cord, slip it over the tooth, and position the loop in the
sulcus around the prepared tooth.
5) Using the cord-packing instrument and working in a clockwise direction, pack the
cord gently into the sulcus surrounding the prepared tooth, so that the ends are on the
facial aspect. The ends in this position are easier to reach for removal of the cord.
6) Pack the cord into the sulcus by gently rocking the instrument slightly backward as
the instrument is moved forward to the next loose section of retraction cord. Repeat this
action until the length of cord is packed in place.
7) Overlap the cord where it meets the first end of the cord. The ends may be tucked
into the sulcus on the facial aspect. An alternative is to leave a short length of cord
sticking out of the sulcus. This makes it easier to grasp and quickly remove the cord.
When a wider and deeper sulcus is required, two retraction cords may be placed with
one on top of the other. Before the impression material is taken, remove the top cord.
After the impression is completed, remove the second retraction cord.
8) The cord should be left in place for a maximum of 5-7 minutes. Instruct the pt to
remain still to keep the area dry. This time allows the cord to push tiss
✔✔Fabricating and cementing a custom acrylic provisional crown (EFDA) - ✔✔1)
Obtain an alginate impression of the arch before the teeth are prepared. You want the
provisional coverage to be a replica of the tooth before the dentist prepares it.
2) Check the impression to be sure it is free of debris and tears in the area selected for
construction of the provisional crown or bridge covering.
3) Disinfect the impression and keep moist until needed. If allowed to dry, the
impression will be distorted, and the provisional coverage will not fit.
4) Isolate the prepared tooth with cotton rolls to maintain moisture control.
5) Lightly apply petroleum jelly or a liquid medium to the prepared tooth to facilitate
separation of the acrylic dough from the preparations.
6) If using the liquid/powder acrylic material, place the liquid monomer in the glass
dappen dish; 10 drops of liquid per unit is recommended. Quickly dispense the selected
shade of self-curing powder (polymer) into the monomer until the powder is saturated.
Cover the monomer container immediately; this material is volatile. If using the syringe-
type acrylic material, skip to step 9.
,7) Use a small spatula to blend the powder and liquid to a homogeneous mixture.
8) Set the mixed material aside for 1-2 minutes until the resin reached a doughy, less
glossy stage. Do not let the resin cure beyond this point.
9) Unwrap the alginate impression, and gently dry the area of the teeth to receive the
provisional coverage.
10) Remove the resin from the mixing container with a small spatula, and immediately
place it within the area of the prepared teeth. Express the acrylic resin from a syringe
directly into the impression.
11) Place the acrylic-loaded impression back into the patient's mouth on the prepared
tooth or teeth.
12) Allow the material to reach an initial set, after approximately 3 minutes, and remove
the tray from the pt's mouth.
13)
✔✔Fabricating and cementing a custom acrylic provisional bridge (EFDA) - ✔✔1) The
thermoplastic tray is prepared before the scheduled appointment and before the teeth
are prepared. The provisional coverage should be a replica of the teeth before the
dentist prepares them.
2) Isolate the prepared teeth to maintain moisture control.
3) Lightly apply petroleum jelly or a liquid medium to the prepared teeth to facilitate
separation of the acrylic dough from the preparations.
4) Prepare the provisional material cartridge for application.
5) Express the acrylic resin from a cartridge directly into the tray.
6) Place the acrylic-loaded tray back into the prepared teeth.
7) Allow the material to reach an initial set, which takes approximately 3 minutes, and
remove the tray from the pt's mouth.
8) Carefully remove the provisional coverage from the tray, and replace it onto the pt's
teeth.
This avoids excess shrinkage during the final curing stage.
9) After final set, remove the provisional coverage and mark the marginal border and
contact points of the provisional coverage w a pencil to provide better visualization of
the markings.
10) Trim the acrylic resin to within 1 mm of the gingival shoulder of the prepared tooth w
an acrylic bur or stone. Any trimming completed by the EFDA must be completed
outside the mouth with use of the lowspeed handpiece and acrylic burs.
11) Check the occlusion, accuracy, and completeness of the provisional coverage, and
adjust as necessary. Remove the provisional coverage from the prepared teeth, and
complete the trimming w an acrylic bur.
12) Remove the provisional coverage and take it to the laboratory where it is polished w
a sterile white rag wheel and pumice on the laboratory lathe. Safety eyewear must be
worn throughout the trimming and polishing procedure. In addition, be aware that the
rag wheel could remove a large bulk of acrylic or could overheat and cau
✔✔Fabricating and cementing a preformed provisional crown (EFDA) - ✔✔1) With the
dentist, examine the prepared tooth for size and shape.
2) Select the preformed crown unit that best suits the area of the mouth.
,3) Try on the crown for size and shape, and make any needed adjustments w a slow-
speed handpiece outside of the mouth.
4) Mix the resin as directed and fill the shell, making sure not to trap any air bubbles in
the material.
5) Seat the shell over the tooth or teeth, and ask the pt to bite down. You will notice
excess resin flowing from the shell into the margins and contacts.
6) Use your fingers to apply pressure to the buccal and lingual areas of the crown.
7) Remove excess resin from the margins after 20 to 30 seconds.
8) Lift the crown on and off the tooth until the resin has hardened. The time required for
setting of this material is approximately 90 seconds. This prevents the crown from
locking onto the tooth.
9) Mark the patient's occlusion with articulating paper and with a pencil around the
margins and contact points, and then adjust using acrylic burs, discs, and rubber
wheels.
10) Finish the crown or bridge.
11) Cement with temporary cement.
12) Document the procedure.
✔✔Repairing a fractured denture (EFDA) - ✔✔1) Disinfect the denture.
2) Align the fractured denture parts and apply sticky wax.
3) Examine the denture and block out all the undercuts on the internal surface that will
be exposed to the plaster with a slurry mix or blockout wax. Blocking out the undercuts
enables you to remove the plaster cast after it sets. Do not block out undercuts along
the fractured line.
4) Prepare a plaster mix.
5) Slowly pour the plaster into the internal surface of the denture. The plaster should
cover the fracture line, but not the entire denture. This is accomplished by holding the
denture in your hand and gently resting it against the vibrator.
6) Place the denture in an upright position and allow the plaster to set.
7) Once the plaster is set, gently remove it from the cast.
8) Remove the sticky wax and pumice.
9) With an acrylic bur, widen the fracture lines on the denture and place retentive
grooves along the fracture line.
10) Apply a thin coat of the acrylic monomer to the fracture lines, then place a small
amount of the acrylic powder, alternating the liquid and powder until the fracture line is
filled.
11) Once the material has cured, the area is smoothed and polished on the dental lathe.
12) The denture is cleaned and disinfected and tried in for for.
13) Document the procedure.
✔✔Preparing and placing a noneugenol periodontal dressing (EFDA) - ✔✔Mixing the
material
1) Extrude equal lengths of the two pastes on the paper pad.
2) Mix the pastes w a wooden tongue depressor until a uniform color has been obtained
(2-3 minutes).
, 3) When the paste loses its tackiness, place it in the paper cup filled with room
temperature water.
4) Lubricate gloved fingers w saline solution. This prevents the material from sticking to
the gloves.
5) Roll the paste into strips approximately the length of the surgical site.
Placing the dressing
6) Press small triangle-shaped pieces of dressing into the interproximal spaces.
7) Adapt one end of the strip around the distal surfaces of the last tooth in the surgical
site.
8) Bring the remainder of the strip forward along the facial surface, and gently press the
strip along the incised gingival margin.
9) Gently press the strip into the interproximal areas.
10) Apply the second strip in the same manner from the lingual side.
11) Join the facial and lingual strips at the distal surface of the last tooth at both ends of
the surgical site.
12) Apply gentle pressure on the facial and lingual surfaces.
13) Check the dressing for overextension and interference w occlusion. Excess packing
irritates the mucobuccal fold and the floor of the mouth.
14) Remove any excess dressing, and adjust the new margins to remove any
roughness. If the pack is not adapted properly, it can break off.
15) Document the procedure.
✔✔Removing a periodontal dressing (EFDA) - ✔✔1) Gently insert the spoon excavator
under the margin.
2) Use lateral pressure to pry the dressing gently away from the tissue. The area may
still be sensitive, and the newly healed tissue is delicate and easily injured.
3) If sutures are embedded in the dressing material, cut the suture material free.
Remove the sutures gently from the tissue. Accidentally pulling the sutures could be
painful for the pt and might open the wound.
4) Gently use dental floss to remove all fragments of dressing material from the
interproximal surfaces. Remaining fragments could cause discomfort for the pt and
result in tissue irritation.
5) Irrigate the entire area gently w warm saline solution to remove the superficial debris.
6) Use the HVE tip or saliva ejector to remove the fluid from the pt's mouth.
7) Document the procedure.
✔✔Performing suture removal (EFDA) - ✔✔1) The surgeon will examine the surgical
site to evaluate healing. If healing is satisfactory, the sutures may be removed.
2) Swab the site w an antiseptic agent to remove any debris.
3) Use cotton pliers to hold the suture gently away from the tissue to expose the
attachment of the knot.
4) Slip one blade of the suture scissors gently under the suture. Cut near the tissue.
5) Use cotton pliers to grasp the knot, and gently tug it so the suture slides through the
tissue. Never pull the knot through the tissue.
AND SOLUTIONS RATED A+
✔✔Placing and removing gingival retraction cord (EFDA) - ✔✔Preparation
1) Rinse and gently dry the prepared tooth; isolate the quadrant w cotton rolls. Dry
tissue makes it easier to see the details of the gingival tissue and place the retraction
cord.
2) Cut a piece of retraction cord 1 to 1.5 inches in length, depending on the size and
type of tooth under preparation. The length is determined by the circumference of the
prepared tooth and the placement technique to be used.
3) Use cotton pliers to form a loose loop of the cord. This makes the cord easy to slip
over the tooth, but the loop is not tied or knotted.
Placement
4) Make a loop in the retraction cord, slip it over the tooth, and position the loop in the
sulcus around the prepared tooth.
5) Using the cord-packing instrument and working in a clockwise direction, pack the
cord gently into the sulcus surrounding the prepared tooth, so that the ends are on the
facial aspect. The ends in this position are easier to reach for removal of the cord.
6) Pack the cord into the sulcus by gently rocking the instrument slightly backward as
the instrument is moved forward to the next loose section of retraction cord. Repeat this
action until the length of cord is packed in place.
7) Overlap the cord where it meets the first end of the cord. The ends may be tucked
into the sulcus on the facial aspect. An alternative is to leave a short length of cord
sticking out of the sulcus. This makes it easier to grasp and quickly remove the cord.
When a wider and deeper sulcus is required, two retraction cords may be placed with
one on top of the other. Before the impression material is taken, remove the top cord.
After the impression is completed, remove the second retraction cord.
8) The cord should be left in place for a maximum of 5-7 minutes. Instruct the pt to
remain still to keep the area dry. This time allows the cord to push tiss
✔✔Fabricating and cementing a custom acrylic provisional crown (EFDA) - ✔✔1)
Obtain an alginate impression of the arch before the teeth are prepared. You want the
provisional coverage to be a replica of the tooth before the dentist prepares it.
2) Check the impression to be sure it is free of debris and tears in the area selected for
construction of the provisional crown or bridge covering.
3) Disinfect the impression and keep moist until needed. If allowed to dry, the
impression will be distorted, and the provisional coverage will not fit.
4) Isolate the prepared tooth with cotton rolls to maintain moisture control.
5) Lightly apply petroleum jelly or a liquid medium to the prepared tooth to facilitate
separation of the acrylic dough from the preparations.
6) If using the liquid/powder acrylic material, place the liquid monomer in the glass
dappen dish; 10 drops of liquid per unit is recommended. Quickly dispense the selected
shade of self-curing powder (polymer) into the monomer until the powder is saturated.
Cover the monomer container immediately; this material is volatile. If using the syringe-
type acrylic material, skip to step 9.
,7) Use a small spatula to blend the powder and liquid to a homogeneous mixture.
8) Set the mixed material aside for 1-2 minutes until the resin reached a doughy, less
glossy stage. Do not let the resin cure beyond this point.
9) Unwrap the alginate impression, and gently dry the area of the teeth to receive the
provisional coverage.
10) Remove the resin from the mixing container with a small spatula, and immediately
place it within the area of the prepared teeth. Express the acrylic resin from a syringe
directly into the impression.
11) Place the acrylic-loaded impression back into the patient's mouth on the prepared
tooth or teeth.
12) Allow the material to reach an initial set, after approximately 3 minutes, and remove
the tray from the pt's mouth.
13)
✔✔Fabricating and cementing a custom acrylic provisional bridge (EFDA) - ✔✔1) The
thermoplastic tray is prepared before the scheduled appointment and before the teeth
are prepared. The provisional coverage should be a replica of the teeth before the
dentist prepares them.
2) Isolate the prepared teeth to maintain moisture control.
3) Lightly apply petroleum jelly or a liquid medium to the prepared teeth to facilitate
separation of the acrylic dough from the preparations.
4) Prepare the provisional material cartridge for application.
5) Express the acrylic resin from a cartridge directly into the tray.
6) Place the acrylic-loaded tray back into the prepared teeth.
7) Allow the material to reach an initial set, which takes approximately 3 minutes, and
remove the tray from the pt's mouth.
8) Carefully remove the provisional coverage from the tray, and replace it onto the pt's
teeth.
This avoids excess shrinkage during the final curing stage.
9) After final set, remove the provisional coverage and mark the marginal border and
contact points of the provisional coverage w a pencil to provide better visualization of
the markings.
10) Trim the acrylic resin to within 1 mm of the gingival shoulder of the prepared tooth w
an acrylic bur or stone. Any trimming completed by the EFDA must be completed
outside the mouth with use of the lowspeed handpiece and acrylic burs.
11) Check the occlusion, accuracy, and completeness of the provisional coverage, and
adjust as necessary. Remove the provisional coverage from the prepared teeth, and
complete the trimming w an acrylic bur.
12) Remove the provisional coverage and take it to the laboratory where it is polished w
a sterile white rag wheel and pumice on the laboratory lathe. Safety eyewear must be
worn throughout the trimming and polishing procedure. In addition, be aware that the
rag wheel could remove a large bulk of acrylic or could overheat and cau
✔✔Fabricating and cementing a preformed provisional crown (EFDA) - ✔✔1) With the
dentist, examine the prepared tooth for size and shape.
2) Select the preformed crown unit that best suits the area of the mouth.
,3) Try on the crown for size and shape, and make any needed adjustments w a slow-
speed handpiece outside of the mouth.
4) Mix the resin as directed and fill the shell, making sure not to trap any air bubbles in
the material.
5) Seat the shell over the tooth or teeth, and ask the pt to bite down. You will notice
excess resin flowing from the shell into the margins and contacts.
6) Use your fingers to apply pressure to the buccal and lingual areas of the crown.
7) Remove excess resin from the margins after 20 to 30 seconds.
8) Lift the crown on and off the tooth until the resin has hardened. The time required for
setting of this material is approximately 90 seconds. This prevents the crown from
locking onto the tooth.
9) Mark the patient's occlusion with articulating paper and with a pencil around the
margins and contact points, and then adjust using acrylic burs, discs, and rubber
wheels.
10) Finish the crown or bridge.
11) Cement with temporary cement.
12) Document the procedure.
✔✔Repairing a fractured denture (EFDA) - ✔✔1) Disinfect the denture.
2) Align the fractured denture parts and apply sticky wax.
3) Examine the denture and block out all the undercuts on the internal surface that will
be exposed to the plaster with a slurry mix or blockout wax. Blocking out the undercuts
enables you to remove the plaster cast after it sets. Do not block out undercuts along
the fractured line.
4) Prepare a plaster mix.
5) Slowly pour the plaster into the internal surface of the denture. The plaster should
cover the fracture line, but not the entire denture. This is accomplished by holding the
denture in your hand and gently resting it against the vibrator.
6) Place the denture in an upright position and allow the plaster to set.
7) Once the plaster is set, gently remove it from the cast.
8) Remove the sticky wax and pumice.
9) With an acrylic bur, widen the fracture lines on the denture and place retentive
grooves along the fracture line.
10) Apply a thin coat of the acrylic monomer to the fracture lines, then place a small
amount of the acrylic powder, alternating the liquid and powder until the fracture line is
filled.
11) Once the material has cured, the area is smoothed and polished on the dental lathe.
12) The denture is cleaned and disinfected and tried in for for.
13) Document the procedure.
✔✔Preparing and placing a noneugenol periodontal dressing (EFDA) - ✔✔Mixing the
material
1) Extrude equal lengths of the two pastes on the paper pad.
2) Mix the pastes w a wooden tongue depressor until a uniform color has been obtained
(2-3 minutes).
, 3) When the paste loses its tackiness, place it in the paper cup filled with room
temperature water.
4) Lubricate gloved fingers w saline solution. This prevents the material from sticking to
the gloves.
5) Roll the paste into strips approximately the length of the surgical site.
Placing the dressing
6) Press small triangle-shaped pieces of dressing into the interproximal spaces.
7) Adapt one end of the strip around the distal surfaces of the last tooth in the surgical
site.
8) Bring the remainder of the strip forward along the facial surface, and gently press the
strip along the incised gingival margin.
9) Gently press the strip into the interproximal areas.
10) Apply the second strip in the same manner from the lingual side.
11) Join the facial and lingual strips at the distal surface of the last tooth at both ends of
the surgical site.
12) Apply gentle pressure on the facial and lingual surfaces.
13) Check the dressing for overextension and interference w occlusion. Excess packing
irritates the mucobuccal fold and the floor of the mouth.
14) Remove any excess dressing, and adjust the new margins to remove any
roughness. If the pack is not adapted properly, it can break off.
15) Document the procedure.
✔✔Removing a periodontal dressing (EFDA) - ✔✔1) Gently insert the spoon excavator
under the margin.
2) Use lateral pressure to pry the dressing gently away from the tissue. The area may
still be sensitive, and the newly healed tissue is delicate and easily injured.
3) If sutures are embedded in the dressing material, cut the suture material free.
Remove the sutures gently from the tissue. Accidentally pulling the sutures could be
painful for the pt and might open the wound.
4) Gently use dental floss to remove all fragments of dressing material from the
interproximal surfaces. Remaining fragments could cause discomfort for the pt and
result in tissue irritation.
5) Irrigate the entire area gently w warm saline solution to remove the superficial debris.
6) Use the HVE tip or saliva ejector to remove the fluid from the pt's mouth.
7) Document the procedure.
✔✔Performing suture removal (EFDA) - ✔✔1) The surgeon will examine the surgical
site to evaluate healing. If healing is satisfactory, the sutures may be removed.
2) Swab the site w an antiseptic agent to remove any debris.
3) Use cotton pliers to hold the suture gently away from the tissue to expose the
attachment of the knot.
4) Slip one blade of the suture scissors gently under the suture. Cut near the tissue.
5) Use cotton pliers to grasp the knot, and gently tug it so the suture slides through the
tissue. Never pull the knot through the tissue.
