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Fabrication and use of a metal reinforcing frame in a fracture-prone mandibular complete denture
Fabrication and use of a metal reinforcing frame in a fracture-prone mandibular complete denture William S. Jameson, DDSa Tucson, Ariz. A procedure to reinforce mandibular complete dentures with a rigid internal horseshoe-shaped frame is described. Sequential clinical and laboratory procedures to incorporate a metal frame at a predetermined, controlled position within the prosthesis are presented. This procedure provides not only strength but ensures adequate space for a resilient liner if required. (J Prosthet Dent 2000;83:476-9.)
A
n approach to achieving mandibular denture stability is to place the peripheral extension of the denture border superior to the muscle attachments (Fig. 1), namely, in a myostatic position.1 Myostatic is a term defined by Frush to describe an area or location on the mandible that remains static or immobile regardless of muscle activity.1 In addition, if the occlusal forces can be confined within an area that does not cause torquing or tilting of the denture during function,2 a remarkably stable prosthesis can be provided. With this approach, the anterior segment of the prosthesis is superior to the buccal frenums, mentalis muscle, and lingual frenum attachments. In situations where extensive resorption of the residual ridge has occurred, it is not uncommon to have a buccolingual width of 5 mm or less. The potential for denture fracture is therefore inherent. Coupled with the fact that many persons having this condition are geriatric and handicapped by arthritis and other infirmities that limit their dexterity, the risk of breakage increases. The use of a metal base or metal mesh within the prosthesis is not a new or original concept.3-5 The approach advocated by the author is a modification of the technique to reinforce silicone-lined dentures described by Morrow.6 It differs in that this approach permits treatment to proceed normally while, concurrently, the metal frame is being fabricated, and then incorporated accurately just before finalizing the wax-up for processing without altering the prosthetic tooth arrangement or relationship of the teeth to the master cast. In the technique advanced by Morrow,6 the artificial teeth are set and approved for processing and finishing. A stone occlusal index is made on the articulator of the occlusal and incisal surfaces of the lower teeth. The wax is then eliminated from the master cast and the reinforcing metal frame with 8 positioning struts to keep the frame suspended above the residual ridge is fabricated. When this has been accomplished, it is placed on the master cast and returned to the articulator. It is then included in the lower denture wax-up using the occlusal aConsultant,
Department Of Veterans Affairs.
476 THE JOURNAL OF PROSTHETIC DENTISTRY
Fig. 1. Myostatic outline for mandibular denture is indicated in red. Areas to be “dimpled” are indicated by solid red dots. Outline of tissue stop in anterior is indicated by open black rectangle.
index with the teeth attached. The occlusal index is removed, the maxillary wax denture returned to the articulator and the occlusion modified and refined as needed. It is my opinion that this technique is more time-consuming and requires a duplication of effort. The solid metal base with beads or latticework for acrylic retention as described by Massad1 must be fabricated with metal anterior and posterior tissue stops before determining the vertical dimension and centric relation because the metal base will be incorporated into the recording trial base. This delays the clinical procedures until the metal work is accomplished. It is then necessary to flow wax beneath the metal base on the master cast for tissue contact to be stable. This is difficult and more prone to inaccuracy than building a base over sheets of baseplate wax adapted and sealed to the master cast. It is also a more difficult laboratory procedure to flow refractory material between the elevated beaded baseplate wax and the refractory cast without trapping air bubbles when investing for casting, as required with this technique. An added advantage of the proposed technique is that a predetermined amount of space between the VOLUME 83 NUMBER 4
JAMESON
Fig. 2. Wax spacer short of retromolar pads and within peripheral outline; cast is exposed in anterior midline area. Eight positioning dimples lateral to wax spacer have also been prepared.
metal and the residual ridge can be provided. Subsequent relining with hard or resilient material can be accomplished without exposing the metal. When the use of a resilient liner is anticipated, this technique ensures the recommended material thickness required for optimal results.7 The required space is ensured by forming a relief spacer with a predetermined number of baseplate wax sheets of known thickness before duplication and production of the refractory cast. With a narrow, flat ridge-and-border configuration, rigidity of the metal frame can be ensured with solid metal approximately 0.75 to 1 mm thick rather than open mesh in the anterior region. The actual thickness is somewhat a matter of personal judgment. With the principles used when designing a maxillary removable partial denture major connector, a broad palatal strap in 2 planes can be kept thin, whereas a palatal bar must be thick to achieve rigidity. Another concern is the potential for the metal frame to show through the somewhat translucent high-impact resin. To overcome this undesirable esthetic caveat, pink opaque should be applied to mask the metal. If the metal frame is to be fabricated at a second laboratory, it will be prudent to make a duplicate stone cast of the altered master cast. This can be performed accurately by the dentist with irreversible hydrocolloid and an oversized impression tray, a 2.5:1 water-to-powder ratio of irreversible hydrocolloid and a duplicating flask, or using polyvinyl-siloxane duplicating material (Silflex III, Austenal, Inc, Chicago, Ill.). The design can be drawn on the resultant stone cast and forwarded for fabrication without having to delay treatment until the master cast is returned with the frame. This article describes a procedure to reinforce mandibular complete dentures with a rigid internal horseshoe frame. Not only will the denture be reinforced, but the metal frame can be positioned at a predetermined, APRIL 2000
THE JOURNAL OF PROSTHETIC DENTISTRY
Fig. 3. Finished chrome-cobalt frame on master cast, with space between frame and cast.
controlled position within the prosthesis. By doing so, the prosthesis is not only strengthened, but, should it be required, adequate space for a resilient line is ensured without compromising the integrity of the frame.
PROCEDURE 1. Fabricate maxillary and mandibular master casts with the technique of choice. 2. Locate the anatomic landmarks and draw the myostatic outline for the mandibular denture base on the cast. This should be verified visually by the operator intraorally with the patient. 3. For 2-mm available relief space, 2 sheets of 1.3-mm thick baseplate wax (Geneva 2000 Set-Up Wax, Geneva Dental, Inc, Beverly Hills, Calif.) should be placed and sealed to the cast at the scribed outline, but short of the retromolar pads. Cut a window through the wax to the cast in the anterior midline area. Prepare 4 “dimples” in the cast with a No. 12 bur on either side of the arch lateral to the myostatic outline (Fig. 2). (These “dimples” will facilitate placement of the reinforcing frame before processing the denture.) 4. Duplicate the master cast with the wax spacer. Fill the negative space with stone for the production of a diagnostic cast. (The design is drawn on the stone cast to augment the written prescription. This stone cast will be duplicated for the production of the refractory cast.) Perform wax-up, casting, and finishing procedures for the metal frame while the customary clinical and laboratory procedures are being executed by the operator8 (Fig. 3). 5. After duplication and production of the diagnostic cast, (the operator or laboratory technician) add an additional sheet of baseplate wax to those previously applied to the master cast and a stable trial base is fabricated (VLC material or C-Plast methyl methacrylate, Geneva Dental Inc). (This addition477
THE JOURNAL OF PROSTHETIC DENTISTRY
Fig. 4. Tissue side of stable trial base revealing tissue stops on retromolar pads and in anterior midline region.
Fig. 5. Complete set-up verified in mouth and maxillary trial denture has been sealed to cast. Wax spacer is still in place on tissue side of mandibular trial base. Linear occlusion was used for this denture set-up, which dictated 0.020-in. anterior separation of teeth. With this occlusal concept, it is believed that rotation of dentures on anterior ridges with protrusive contact is prevented due to bilateral fulcrum of protrusive stability in first or second premolar area. This produces vertical seating forces behind anterior ridges, creating stability rather than rotational forces with anterior tooth contact.
al sheet of wax will produce the space necessary to accommodate the metal frame during final waxup.) Ensure the anterior “window” is completely filled with the trial base material and the retromolar pads covered (Fig. 4). 6. Vertical dimension and centric relation are determined and recorded with the operator’s technique of choice. Mount the master casts in the articulator of choice and arrange the prosthetic teeth. The verification and acceptance appointment is then accomplished (Fig. 5). 478
JAMESON
Fig. 6. Metal frame in position on master cast after treatment with Siloc and application of pink opaque. Positioning struts, which will be removed during finishing, need not be opaqued. Wax spacer has been removed and trial base positioned over metal frame. Base is in contact with cast, both in anterior and posterior regions. Beading of cast for accurate border determination during finishing is visible lingual to buccal struts.
7. After receiving the patient’s permission to process the denture, remove the wax spacer from the tissue side of the stable trial base and “bead” or score the cast with a No. 2 bur just lateral to the scribed outline. Place the metal-reinforcing frame with its 8 positioning struts or legs in the indentations on the cast. (Because of the narrow anterior width and the required “window” opening, the metal frame should be solid in this area for strength with beads for resin retention.) Prepare the metal frame with Siloc bonding method (silica coating, Heraeus Kulzer, Inc, Irvine, Calif.) to achieve a chemicalmicromechanical bond between the denture base material and the dental alloys. (The Siloc method is similar to silicoating but, according to the manufacturer, is improved to eliminate debonding. A pink opaquer is applied to reduce metal visibility through the high-impact, but somewhat translucent, resin.) The additional space provided by the sheet of baseplate wax that was added after duplication will permit placement of the trial base over the frame without interference (Fig. 6). 8. Seal the base to the cast and finalize the wax-up (Fig. 7). To prevent dislodgment of the denture from the cast after processing and during recovery and divesting, make undercuts in the stone cast beneath the mylohyoid ridge on each side and in the genial tubercle area. Fill these cut areas with wax and join to the denture wax-up. 9. If the base is to be tinted or color characterized, either by the Pound9 or reverse Pound technique used by Hardy,10 invest the metal frame to be VOLUME 83 NUMBER 4
JAMESON
THE JOURNAL OF PROSTHETIC DENTISTRY
Fig. 7. Final wax-up is ready for processing. This lingual view of final wax-up reveals wax extensions into prepared retaining areas in retromolar and genial tubercle areas. Exposed struts will be captured in investing stone.
Fig. 8. Completed, color-characterized mandibular denture. Anterior strut has been countersunk and covered with autopolymerizing resin. Nonobtrusive posterior strut has been cut flush with base, then smoothed and polished.
retained in the lower, or drag, portion of the flask. If a resilient liner is to be processed simultaneously with the base resin using compression molding procedures, it will be necessary for the frame to be retained in the upper, or cope, half of the flask. (This permits the use of a spacer beneath the frame, producing a void that is filled with resilient material after the resin has stiffened sufficiently and before final closure.6) 10. After processing, remount and correct the occlusion to eliminate processing errors. Recover the dentures from the master casts, then finish and polish. As a part of the finishing procedures, cut the framework struts flush with the acrylic resin. If the exposed metal is objectionable, it can be countersunk and covered with autopolymerizing resin (Fig. 8).
for the metal frame to be produced at a remote location to the denture laboratory. The communication and coordination necessary should be no more difficult than coordinating a removable partial framework in conjunction with a complete denture when both are required to restore a patient.
DISCUSSION A sequential approach in fabricating a stable mandibular denture with a reinforcing metal frame is presented. Weight, resistance to midline fracture, and sufficient available denture thickness for subsequent relining are advantages achieved with this technique. This procedure will reduce the possibility of midline fracture in the myostatic mandibular denture. Although implementing this procedure might be considered unnecessary if high-impact denture base material (Ivocap, Ivoclar Williams, Amherst, N.Y.; Lucitone 199, Dentsply International, Inc, York, Pa.; Microfit VR 90, Vynacron Co, Matawau, N.J.) is to be used, it could be a timely precaution to avoid a potential disaster. The disadvantage of this procedure would be the added cost for the metal frame and the additional steps needed for its inclusion. If the dentist is not using a full-service laboratory, it will be necessary to arrange APRIL 2000
REFERENCES 1. Massad JJ. A metal-based denture with soft liner to accommodate the severely resorbed mandibular alveolar ridge. J Prosthet Dent 1987;57: 707-11. 2. Lang BR, Kelsey CC. International prosthodontic workshop on complete denture occlusion. Ann Arbor: The University of Michigan School of Dentistry; 1973. p. 154-8. 3. Strahl RC, Streckfus CF. The utilization of mandibular metal base dentures for patients with severe mandibular alveolar bone atrophy. J Md State Dent Assoc 1984;27:68-71. 4. Faber BL. Lower cast metal denture. J Prosthet Dent 1957;7:51-4. 5. Grunewald AH. Gold base lower dentures. J Prosthet Dent 1964;14:432-41. 6. Morrow RM, Reiner PR, Feldman EE, Rudd KD. Metal reinforcing siliconelined dentures. J Prosthet Dent 1968;19:219-29. 7. Marginis MJ, Gauber GT. Soft liners. In: Morrow RM, Rudd KD, Eissmann HF, editors. Dental laboratory procedures complete dentures. Vol I. St Louis: Mosby; 1980. p. 432-46. 8. Brudvik JS. Metal bases. In: Morrow RM, Rudd KD, Eissmann HF, editors. Dental laboratory procedures complete dentures. Vol I. St Louis: Mosby; 1980. p. 447-65. 9. Pound E. Esthetic dentures and their phonetic values. J Prosthet Dent 1951;1:98-111. 10. Hardy IR. Problem-solving in denture esthetics. In: Payne SH, editor. Dental Clinics of North America. Philadelphia: WB Saunders; 1960. p. 305-20. Reprint requests to: DR WILLIAM S. JAMESON 11401 CALLE VAQUEROS TUCSON, AZ 85749-8483 FAX: (520)749-1511 E-MAIL: [email protected] Copyright © 2000 by The Editorial Council of The Journal of Prosthetic Dentistry. 0022-3913/2000/$12.00 + 0. 10/1/105882 doi:10.1067/mpr.2000.105882
479
A
n approach to achieving mandibular denture stability is to place the peripheral extension of the denture border superior to the muscle attachments (Fig. 1), namely, in a myostatic position.1 Myostatic is a term defined by Frush to describe an area or location on the mandible that remains static or immobile regardless of muscle activity.1 In addition, if the occlusal forces can be confined within an area that does not cause torquing or tilting of the denture during function,2 a remarkably stable prosthesis can be provided. With this approach, the anterior segment of the prosthesis is superior to the buccal frenums, mentalis muscle, and lingual frenum attachments. In situations where extensive resorption of the residual ridge has occurred, it is not uncommon to have a buccolingual width of 5 mm or less. The potential for denture fracture is therefore inherent. Coupled with the fact that many persons having this condition are geriatric and handicapped by arthritis and other infirmities that limit their dexterity, the risk of breakage increases. The use of a metal base or metal mesh within the prosthesis is not a new or original concept.3-5 The approach advocated by the author is a modification of the technique to reinforce silicone-lined dentures described by Morrow.6 It differs in that this approach permits treatment to proceed normally while, concurrently, the metal frame is being fabricated, and then incorporated accurately just before finalizing the wax-up for processing without altering the prosthetic tooth arrangement or relationship of the teeth to the master cast. In the technique advanced by Morrow,6 the artificial teeth are set and approved for processing and finishing. A stone occlusal index is made on the articulator of the occlusal and incisal surfaces of the lower teeth. The wax is then eliminated from the master cast and the reinforcing metal frame with 8 positioning struts to keep the frame suspended above the residual ridge is fabricated. When this has been accomplished, it is placed on the master cast and returned to the articulator. It is then included in the lower denture wax-up using the occlusal aConsultant,
Department Of Veterans Affairs.
476 THE JOURNAL OF PROSTHETIC DENTISTRY
Fig. 1. Myostatic outline for mandibular denture is indicated in red. Areas to be “dimpled” are indicated by solid red dots. Outline of tissue stop in anterior is indicated by open black rectangle.
index with the teeth attached. The occlusal index is removed, the maxillary wax denture returned to the articulator and the occlusion modified and refined as needed. It is my opinion that this technique is more time-consuming and requires a duplication of effort. The solid metal base with beads or latticework for acrylic retention as described by Massad1 must be fabricated with metal anterior and posterior tissue stops before determining the vertical dimension and centric relation because the metal base will be incorporated into the recording trial base. This delays the clinical procedures until the metal work is accomplished. It is then necessary to flow wax beneath the metal base on the master cast for tissue contact to be stable. This is difficult and more prone to inaccuracy than building a base over sheets of baseplate wax adapted and sealed to the master cast. It is also a more difficult laboratory procedure to flow refractory material between the elevated beaded baseplate wax and the refractory cast without trapping air bubbles when investing for casting, as required with this technique. An added advantage of the proposed technique is that a predetermined amount of space between the VOLUME 83 NUMBER 4
JAMESON
Fig. 2. Wax spacer short of retromolar pads and within peripheral outline; cast is exposed in anterior midline area. Eight positioning dimples lateral to wax spacer have also been prepared.
metal and the residual ridge can be provided. Subsequent relining with hard or resilient material can be accomplished without exposing the metal. When the use of a resilient liner is anticipated, this technique ensures the recommended material thickness required for optimal results.7 The required space is ensured by forming a relief spacer with a predetermined number of baseplate wax sheets of known thickness before duplication and production of the refractory cast. With a narrow, flat ridge-and-border configuration, rigidity of the metal frame can be ensured with solid metal approximately 0.75 to 1 mm thick rather than open mesh in the anterior region. The actual thickness is somewhat a matter of personal judgment. With the principles used when designing a maxillary removable partial denture major connector, a broad palatal strap in 2 planes can be kept thin, whereas a palatal bar must be thick to achieve rigidity. Another concern is the potential for the metal frame to show through the somewhat translucent high-impact resin. To overcome this undesirable esthetic caveat, pink opaque should be applied to mask the metal. If the metal frame is to be fabricated at a second laboratory, it will be prudent to make a duplicate stone cast of the altered master cast. This can be performed accurately by the dentist with irreversible hydrocolloid and an oversized impression tray, a 2.5:1 water-to-powder ratio of irreversible hydrocolloid and a duplicating flask, or using polyvinyl-siloxane duplicating material (Silflex III, Austenal, Inc, Chicago, Ill.). The design can be drawn on the resultant stone cast and forwarded for fabrication without having to delay treatment until the master cast is returned with the frame. This article describes a procedure to reinforce mandibular complete dentures with a rigid internal horseshoe frame. Not only will the denture be reinforced, but the metal frame can be positioned at a predetermined, APRIL 2000
THE JOURNAL OF PROSTHETIC DENTISTRY
Fig. 3. Finished chrome-cobalt frame on master cast, with space between frame and cast.
controlled position within the prosthesis. By doing so, the prosthesis is not only strengthened, but, should it be required, adequate space for a resilient line is ensured without compromising the integrity of the frame.
PROCEDURE 1. Fabricate maxillary and mandibular master casts with the technique of choice. 2. Locate the anatomic landmarks and draw the myostatic outline for the mandibular denture base on the cast. This should be verified visually by the operator intraorally with the patient. 3. For 2-mm available relief space, 2 sheets of 1.3-mm thick baseplate wax (Geneva 2000 Set-Up Wax, Geneva Dental, Inc, Beverly Hills, Calif.) should be placed and sealed to the cast at the scribed outline, but short of the retromolar pads. Cut a window through the wax to the cast in the anterior midline area. Prepare 4 “dimples” in the cast with a No. 12 bur on either side of the arch lateral to the myostatic outline (Fig. 2). (These “dimples” will facilitate placement of the reinforcing frame before processing the denture.) 4. Duplicate the master cast with the wax spacer. Fill the negative space with stone for the production of a diagnostic cast. (The design is drawn on the stone cast to augment the written prescription. This stone cast will be duplicated for the production of the refractory cast.) Perform wax-up, casting, and finishing procedures for the metal frame while the customary clinical and laboratory procedures are being executed by the operator8 (Fig. 3). 5. After duplication and production of the diagnostic cast, (the operator or laboratory technician) add an additional sheet of baseplate wax to those previously applied to the master cast and a stable trial base is fabricated (VLC material or C-Plast methyl methacrylate, Geneva Dental Inc). (This addition477
THE JOURNAL OF PROSTHETIC DENTISTRY
Fig. 4. Tissue side of stable trial base revealing tissue stops on retromolar pads and in anterior midline region.
Fig. 5. Complete set-up verified in mouth and maxillary trial denture has been sealed to cast. Wax spacer is still in place on tissue side of mandibular trial base. Linear occlusion was used for this denture set-up, which dictated 0.020-in. anterior separation of teeth. With this occlusal concept, it is believed that rotation of dentures on anterior ridges with protrusive contact is prevented due to bilateral fulcrum of protrusive stability in first or second premolar area. This produces vertical seating forces behind anterior ridges, creating stability rather than rotational forces with anterior tooth contact.
al sheet of wax will produce the space necessary to accommodate the metal frame during final waxup.) Ensure the anterior “window” is completely filled with the trial base material and the retromolar pads covered (Fig. 4). 6. Vertical dimension and centric relation are determined and recorded with the operator’s technique of choice. Mount the master casts in the articulator of choice and arrange the prosthetic teeth. The verification and acceptance appointment is then accomplished (Fig. 5). 478
JAMESON
Fig. 6. Metal frame in position on master cast after treatment with Siloc and application of pink opaque. Positioning struts, which will be removed during finishing, need not be opaqued. Wax spacer has been removed and trial base positioned over metal frame. Base is in contact with cast, both in anterior and posterior regions. Beading of cast for accurate border determination during finishing is visible lingual to buccal struts.
7. After receiving the patient’s permission to process the denture, remove the wax spacer from the tissue side of the stable trial base and “bead” or score the cast with a No. 2 bur just lateral to the scribed outline. Place the metal-reinforcing frame with its 8 positioning struts or legs in the indentations on the cast. (Because of the narrow anterior width and the required “window” opening, the metal frame should be solid in this area for strength with beads for resin retention.) Prepare the metal frame with Siloc bonding method (silica coating, Heraeus Kulzer, Inc, Irvine, Calif.) to achieve a chemicalmicromechanical bond between the denture base material and the dental alloys. (The Siloc method is similar to silicoating but, according to the manufacturer, is improved to eliminate debonding. A pink opaquer is applied to reduce metal visibility through the high-impact, but somewhat translucent, resin.) The additional space provided by the sheet of baseplate wax that was added after duplication will permit placement of the trial base over the frame without interference (Fig. 6). 8. Seal the base to the cast and finalize the wax-up (Fig. 7). To prevent dislodgment of the denture from the cast after processing and during recovery and divesting, make undercuts in the stone cast beneath the mylohyoid ridge on each side and in the genial tubercle area. Fill these cut areas with wax and join to the denture wax-up. 9. If the base is to be tinted or color characterized, either by the Pound9 or reverse Pound technique used by Hardy,10 invest the metal frame to be VOLUME 83 NUMBER 4
JAMESON
THE JOURNAL OF PROSTHETIC DENTISTRY
Fig. 7. Final wax-up is ready for processing. This lingual view of final wax-up reveals wax extensions into prepared retaining areas in retromolar and genial tubercle areas. Exposed struts will be captured in investing stone.
Fig. 8. Completed, color-characterized mandibular denture. Anterior strut has been countersunk and covered with autopolymerizing resin. Nonobtrusive posterior strut has been cut flush with base, then smoothed and polished.
retained in the lower, or drag, portion of the flask. If a resilient liner is to be processed simultaneously with the base resin using compression molding procedures, it will be necessary for the frame to be retained in the upper, or cope, half of the flask. (This permits the use of a spacer beneath the frame, producing a void that is filled with resilient material after the resin has stiffened sufficiently and before final closure.6) 10. After processing, remount and correct the occlusion to eliminate processing errors. Recover the dentures from the master casts, then finish and polish. As a part of the finishing procedures, cut the framework struts flush with the acrylic resin. If the exposed metal is objectionable, it can be countersunk and covered with autopolymerizing resin (Fig. 8).
for the metal frame to be produced at a remote location to the denture laboratory. The communication and coordination necessary should be no more difficult than coordinating a removable partial framework in conjunction with a complete denture when both are required to restore a patient.
DISCUSSION A sequential approach in fabricating a stable mandibular denture with a reinforcing metal frame is presented. Weight, resistance to midline fracture, and sufficient available denture thickness for subsequent relining are advantages achieved with this technique. This procedure will reduce the possibility of midline fracture in the myostatic mandibular denture. Although implementing this procedure might be considered unnecessary if high-impact denture base material (Ivocap, Ivoclar Williams, Amherst, N.Y.; Lucitone 199, Dentsply International, Inc, York, Pa.; Microfit VR 90, Vynacron Co, Matawau, N.J.) is to be used, it could be a timely precaution to avoid a potential disaster. The disadvantage of this procedure would be the added cost for the metal frame and the additional steps needed for its inclusion. If the dentist is not using a full-service laboratory, it will be necessary to arrange APRIL 2000
REFERENCES 1. Massad JJ. A metal-based denture with soft liner to accommodate the severely resorbed mandibular alveolar ridge. J Prosthet Dent 1987;57: 707-11. 2. Lang BR, Kelsey CC. International prosthodontic workshop on complete denture occlusion. Ann Arbor: The University of Michigan School of Dentistry; 1973. p. 154-8. 3. Strahl RC, Streckfus CF. The utilization of mandibular metal base dentures for patients with severe mandibular alveolar bone atrophy. J Md State Dent Assoc 1984;27:68-71. 4. Faber BL. Lower cast metal denture. J Prosthet Dent 1957;7:51-4. 5. Grunewald AH. Gold base lower dentures. J Prosthet Dent 1964;14:432-41. 6. Morrow RM, Reiner PR, Feldman EE, Rudd KD. Metal reinforcing siliconelined dentures. J Prosthet Dent 1968;19:219-29. 7. Marginis MJ, Gauber GT. Soft liners. In: Morrow RM, Rudd KD, Eissmann HF, editors. Dental laboratory procedures complete dentures. Vol I. St Louis: Mosby; 1980. p. 432-46. 8. Brudvik JS. Metal bases. In: Morrow RM, Rudd KD, Eissmann HF, editors. Dental laboratory procedures complete dentures. Vol I. St Louis: Mosby; 1980. p. 447-65. 9. Pound E. Esthetic dentures and their phonetic values. J Prosthet Dent 1951;1:98-111. 10. Hardy IR. Problem-solving in denture esthetics. In: Payne SH, editor. Dental Clinics of North America. Philadelphia: WB Saunders; 1960. p. 305-20. Reprint requests to: DR WILLIAM S. JAMESON 11401 CALLE VAQUEROS TUCSON, AZ 85749-8483 FAX: (520)749-1511 E-MAIL: [email protected] Copyright © 2000 by The Editorial Council of The Journal of Prosthetic Dentistry. 0022-3913/2000/$12.00 + 0. 10/1/105882 doi:10.1067/mpr.2000.105882
479