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In-office fabrication of a claspless interim partial denture
SECTIONEDITOR
n-office
s interim
partia
Bijan K.
sa New York University College of Dentistry, New York, N. Y. This article describes a technique for making a claspless interim removable partial denture that can quickly and easily be made in the dental office. The unnecessary undercuts are eliminated by use of a bloc&-out putty without the need for duplication of the cast. The prosthesis can be inserted with minimum adjustment. (J PR~STHET DENT 1993;69:436-8.)
he insertion of a claspiess interim partial denture is usuaily difficult and time-consuming, because of the extension of the Iingual flange of the prosthesis into lingua1 and interproximal undercuts of the teeth, which prevents accurate seating. Difficulty in seating the prosthesis may be encountered with interim partial dentures made in commercial laboratories or those made in the dental ofice during an emergency such as loss of an existing removable partial denture or unexpected extraction of an anterior tooth. This difficulty is due to the lack of proper block-out of the master cast to eliminate the unnecessary lingual and interproximal undercuts of the abutment teeth. To eliminate the undercuts properly by the traditional method, the cast should be surveyed and the height of the contour of the teeth in contact with the prosthesis should be delineated. The lingual undercuts of the teeth should
then be blocked out with wax parallel to the selected path of insertion and 1 mm below the height of the contour of the teeth. The blocked out cast should then be duplicated and a working cast should be made. The partial denture is then waxed up and processed on this cast. This traditional
aAssistant Professor and Director
of Preclinica: Removable Prosthodontics, Division of Restorative and Prosthodontic Sciences. Copyright @ 1993 by The Editorial Comcil of THE JOURNAL OF PROSTHETIC DENTISTRY. 0022-3913/93/$1Bot .lO. 18/P/44266
Pig.
Fig. 1. Two lines scribed on abutment teeth. LTpper line indicates height of contour and lower line 1 mm below it indicates upper limit of block-out material.
Fig. 3. Block-out putty is made parallel tion of prosthesis with a spatula.
436
2. Block-out
putty is injected into undercut on teeth.
to path of inser.-
MOGHADAM
Fig. 4. Labial index made with fast-setting plaster.
Fig. 6. Autopoiymerizing ture base of pro:sthesis.
Fig. 5. Periphery wax used to create wall around outline of denture base.
method allows for easy seating and insertion of the interim partial denture in the mouth; however, it is time-consuming and is not readily feasible in a busy dental office. This article describes a procedure for making a claspless interim removable partial denture in which the unnecessary undercuts are eliminated quickly without the need for duplication of the cast. This procedure can be easily performed in the dental office in a short time and the prosthesis can be easily inserted in the mouth with minimum adjustment. This type of partial denture is meant for temporary use. Prolonged wearing of such an interim partial denture may cause serious or permanent damage to the oral tissues.
PROCEDURE Blocking out the master
cast
1. Mark the height of the contour of the lingual surface of the teeth with a surveyor if available or by holding a pencil perpendicular to the cast. 2. Using a red pencil, scribe a line parallel but 1 mm gin-
APRIL
1993
acrylic resin used to form den-
Fig. 7’. Completed prosthesis on cast.
gival to the survey line (Fig. 1). This line indicates the occlusal limit. of the block-out material. The 1 mm area between the survey line and the red pencil line is the undercut area necessary for retention of the interim partial denture. 3. Block out the lingual and interproximal undercuts located below the red pencil line with Oral Seal putty (Oral Seal Ultradent Production Inc., Salt Lake City, Ut.).’ This is a block-out material with the consistency of caulking compound, which is supplied in a dispensing syringe. When the putty is placed in the working area, it will maintain its integrity and no setting time is required. Inject the putty into the undercut regions (Fig. 2) and mold it parallel to the path of insertion of the prosthesis with a straight cement spatula (Fig. 3), but do not allow it to go occlusal to the red line.
Making
the prosthesis
1. Set the teeth to be replaced by the interim partial dent,ure on the blocked out cast. 437
THE
JOURNAL
OF PROSTHETIC
MOGHADAM
DENTISTRY
6. Remove the labial index and add monomer and polymer to the labial surface of the cast to form the labial flange. 7. After the initial setting of the acrylic resin, place the cast in a pressure pot with 104’ F water for 10 minutes to complete the polymerization.2 8. Separate the interim partial denture from the cast; finish and polish it (Figs. 7 and 8). A procedure for making a claspless interim removable partial denture that could easily be done in the dental office in a short period of time has been described. The prosthesis will engage 1 mm of the lingual undercuts below the height of contour of the teeth to provide adequate retention with easy insertion and minimum adjustment. This procedure eliminates the time-consuming steps of duplication of the block-out cast and making the working cast on which the transitional partial denture is made. This type of denture is meant for temporary use.
Fig. 8. Completed prosthesis in mouth.
2. Make a labial index with fast-setting plaster or a silicone putty (Fig. 4). 3. Coat the cast with a tinfoil substitute material such as Al-Cote (Dentsply Intl., York, Pa.). 4. Mark the outline of the prosthesis with a pencil, with the superior border as the height of the contour. Create a wall around the inferior and posterior outline of the prosthesis with periphery wax.l The wall will prevent the autopolymerizing acrylic resin from flowing into the undesired area of the cast (Fig. 5). 5. Form the base of the prosthesis with pink autopolymerizing acrylic resin and sprinkle technique. (Fig, 6).
~ I
Bound volumes
available
REFERENCES 1. Rudd KD. Morrow RM. Rhoads JE. Dental laboratory procedures. 2nd ed. St Louis: CV Mosby, 1986:78-9. 2. Zarb GA, Bolender CL, Hickey JC, Gunnar CE. Boucher’s prosthodontic treatment for edentulous patients. 10th ed. St Louis: CV Mosby, 1990:589-90.
Reprintrequeststo: BIJAN KH. MOGHADAM 130 CARROLLWOOD DR. TARRYTOWN. NY 10591
to subscribers
Bound volumes of THE JOURNALOFPROSTHETICDENTISTRY are available to subscribers (only) for the 1993 issues from the publisher at a cost of $60.50 ($73.50 international) for Vol. 69 (January-June) and Vol. 70 (July-December). Shipping charges are included. Each bound volume contains a subject and author index, and all advertising is removed. Copies are shipped within 30 days after publication of the last issue in the volume. The binding is durable buckram with the journal name, volume number, and year stamped in gold on the spine. Volumes 67 and 68 are also available. Payment must accompany all orders. Contact Mosby, Subscription Services, 11830 Westline Industrial Drive, St. Louis, MO 63146-3318, USA; phone (800) 325-4177, ext. 4351, or (314)453-4351. Subscriptions must be in force to qualify. Bound volumes are not available in place of a regular JOURNAL subscription.
438
VOLUME
69
NUMBER
4
n-office
s interim
partia
Bijan K.
sa New York University College of Dentistry, New York, N. Y. This article describes a technique for making a claspless interim removable partial denture that can quickly and easily be made in the dental office. The unnecessary undercuts are eliminated by use of a bloc&-out putty without the need for duplication of the cast. The prosthesis can be inserted with minimum adjustment. (J PR~STHET DENT 1993;69:436-8.)
he insertion of a claspiess interim partial denture is usuaily difficult and time-consuming, because of the extension of the Iingual flange of the prosthesis into lingua1 and interproximal undercuts of the teeth, which prevents accurate seating. Difficulty in seating the prosthesis may be encountered with interim partial dentures made in commercial laboratories or those made in the dental ofice during an emergency such as loss of an existing removable partial denture or unexpected extraction of an anterior tooth. This difficulty is due to the lack of proper block-out of the master cast to eliminate the unnecessary lingual and interproximal undercuts of the abutment teeth. To eliminate the undercuts properly by the traditional method, the cast should be surveyed and the height of the contour of the teeth in contact with the prosthesis should be delineated. The lingual undercuts of the teeth should
then be blocked out with wax parallel to the selected path of insertion and 1 mm below the height of the contour of the teeth. The blocked out cast should then be duplicated and a working cast should be made. The partial denture is then waxed up and processed on this cast. This traditional
aAssistant Professor and Director
of Preclinica: Removable Prosthodontics, Division of Restorative and Prosthodontic Sciences. Copyright @ 1993 by The Editorial Comcil of THE JOURNAL OF PROSTHETIC DENTISTRY. 0022-3913/93/$1Bot .lO. 18/P/44266
Pig.
Fig. 1. Two lines scribed on abutment teeth. LTpper line indicates height of contour and lower line 1 mm below it indicates upper limit of block-out material.
Fig. 3. Block-out putty is made parallel tion of prosthesis with a spatula.
436
2. Block-out
putty is injected into undercut on teeth.
to path of inser.-
MOGHADAM
Fig. 4. Labial index made with fast-setting plaster.
Fig. 6. Autopoiymerizing ture base of pro:sthesis.
Fig. 5. Periphery wax used to create wall around outline of denture base.
method allows for easy seating and insertion of the interim partial denture in the mouth; however, it is time-consuming and is not readily feasible in a busy dental office. This article describes a procedure for making a claspless interim removable partial denture in which the unnecessary undercuts are eliminated quickly without the need for duplication of the cast. This procedure can be easily performed in the dental office in a short time and the prosthesis can be easily inserted in the mouth with minimum adjustment. This type of partial denture is meant for temporary use. Prolonged wearing of such an interim partial denture may cause serious or permanent damage to the oral tissues.
PROCEDURE Blocking out the master
cast
1. Mark the height of the contour of the lingual surface of the teeth with a surveyor if available or by holding a pencil perpendicular to the cast. 2. Using a red pencil, scribe a line parallel but 1 mm gin-
APRIL
1993
acrylic resin used to form den-
Fig. 7’. Completed prosthesis on cast.
gival to the survey line (Fig. 1). This line indicates the occlusal limit. of the block-out material. The 1 mm area between the survey line and the red pencil line is the undercut area necessary for retention of the interim partial denture. 3. Block out the lingual and interproximal undercuts located below the red pencil line with Oral Seal putty (Oral Seal Ultradent Production Inc., Salt Lake City, Ut.).’ This is a block-out material with the consistency of caulking compound, which is supplied in a dispensing syringe. When the putty is placed in the working area, it will maintain its integrity and no setting time is required. Inject the putty into the undercut regions (Fig. 2) and mold it parallel to the path of insertion of the prosthesis with a straight cement spatula (Fig. 3), but do not allow it to go occlusal to the red line.
Making
the prosthesis
1. Set the teeth to be replaced by the interim partial dent,ure on the blocked out cast. 437
THE
JOURNAL
OF PROSTHETIC
MOGHADAM
DENTISTRY
6. Remove the labial index and add monomer and polymer to the labial surface of the cast to form the labial flange. 7. After the initial setting of the acrylic resin, place the cast in a pressure pot with 104’ F water for 10 minutes to complete the polymerization.2 8. Separate the interim partial denture from the cast; finish and polish it (Figs. 7 and 8). A procedure for making a claspless interim removable partial denture that could easily be done in the dental office in a short period of time has been described. The prosthesis will engage 1 mm of the lingual undercuts below the height of contour of the teeth to provide adequate retention with easy insertion and minimum adjustment. This procedure eliminates the time-consuming steps of duplication of the block-out cast and making the working cast on which the transitional partial denture is made. This type of denture is meant for temporary use.
Fig. 8. Completed prosthesis in mouth.
2. Make a labial index with fast-setting plaster or a silicone putty (Fig. 4). 3. Coat the cast with a tinfoil substitute material such as Al-Cote (Dentsply Intl., York, Pa.). 4. Mark the outline of the prosthesis with a pencil, with the superior border as the height of the contour. Create a wall around the inferior and posterior outline of the prosthesis with periphery wax.l The wall will prevent the autopolymerizing acrylic resin from flowing into the undesired area of the cast (Fig. 5). 5. Form the base of the prosthesis with pink autopolymerizing acrylic resin and sprinkle technique. (Fig, 6).
~ I
Bound volumes
available
REFERENCES 1. Rudd KD. Morrow RM. Rhoads JE. Dental laboratory procedures. 2nd ed. St Louis: CV Mosby, 1986:78-9. 2. Zarb GA, Bolender CL, Hickey JC, Gunnar CE. Boucher’s prosthodontic treatment for edentulous patients. 10th ed. St Louis: CV Mosby, 1990:589-90.
Reprintrequeststo: BIJAN KH. MOGHADAM 130 CARROLLWOOD DR. TARRYTOWN. NY 10591
to subscribers
Bound volumes of THE JOURNALOFPROSTHETICDENTISTRY are available to subscribers (only) for the 1993 issues from the publisher at a cost of $60.50 ($73.50 international) for Vol. 69 (January-June) and Vol. 70 (July-December). Shipping charges are included. Each bound volume contains a subject and author index, and all advertising is removed. Copies are shipped within 30 days after publication of the last issue in the volume. The binding is durable buckram with the journal name, volume number, and year stamped in gold on the spine. Volumes 67 and 68 are also available. Payment must accompany all orders. Contact Mosby, Subscription Services, 11830 Westline Industrial Drive, St. Louis, MO 63146-3318, USA; phone (800) 325-4177, ext. 4351, or (314)453-4351. Subscriptions must be in force to qualify. Bound volumes are not available in place of a regular JOURNAL subscription.
438
VOLUME
69
NUMBER
4