- Email: [email protected]
Current Practices in Maxillofacial Prosthetics
Symposium on Surgical Oncology
Current Practices in Maxillofacial Prosthetics
James B. Lepley, D.D.S.*
Maxillofacial prosthetics is the art and science of anatomic, functional, or cosmetic reconstruction, by means of nonliving substitutes, of those regions in the maxilla, mandible, and face that are missing or defective because of surgical intervention, trauma, pathology, or developmental or congenital malformation. Since recorded time there is evidence of man's desire to overcome physical deformity, especially about the face and head. Ancient Chinese fabricated missing portions of the face from resins and restored missing eyes with metallic, lacquered globes. Egyptian mummies have been discovered with missing eyes replaced by stone and mosaic replicas. The Romans document the "maker of the eye" as well as "the doctor of the eye." Carried down to modern times is the custom practiced by nomadic desert tribes of severing the hand of a thief. These victims often try to restore the missing hand by fashioning a replacement from animal bones and skin, and vegetable dyes for coloring. Modern man is equally concerned with overcoming physical deformity. No longer is quantity of survival the only measure of success in care of the afflicted; quality of survival has achieved equal import. In his role as a functioning member of the management team of patients with acquired or congenital defects of the head and neck, the maxillofacial prosthodontist is dedicated to the maximum restoration of these individuals to as nearly a normal way of life as possible. Recognizing the fact that reconstruction of a defect with functioning, living tissue is the ultimate and most desired goal, prosthetic restoration is indicated when the defect cannot be successfully bridged with viable tissues, when the age or physical condition of the patient negates surgical reconstruction, and when factors of time and expense contraindicate lengthy and frequent hospitalization, as an intermediate restoration during reconstructive surgical efforts. Perhaps of prime importance is the fact that defects need frequent and continuous follow-up inspection to detect recurrence of disease or other abnormal changes. Prosthetic reconstruction permits this. '''Chief, Dental Service, Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York
Surgical Clinics of North America- Vol. 54, No.4, August 1974
787
788
JAMES
B.
LEPLEY
* Figure 1. A, Palatal defect to be closed. B, Prosthesis with wrought metal clasps for tooth retention in the unaffected maxillary remnant. C, A more sophisticated prosthesis to restore maximum tooth occlusion, phonation, and deglutition.
Prosthetic restoration of defects about the head and neck may be grouped in two broad categories, namely, intra- and extraoral prostheses. In addition, certain prostheses are constructed which are used only during treatment, such as surgical stents and radiation source carriers. Intraoral Prostheses Intraoral prostheses include obturators to close palatal defects, obturator-speech bulb combinations which not only close bony defects but supply missing soft palate as well, and speech bulb prostheses which only replace missing soft palate structures (Fig. lA). These prostheses may be provided either as an immediate procedure and placed in the defect in the operating room or delivered at such time as surgical packs are removed. These prostheses are usually constructed from methylmethacrylate resin and mayor may not, as indicated, have simple wrought metal clasps for retention if any teeth are remaining in the unaffected maxillary remnant (Fig. IB). Minor adjustments are usually necessary to maintain an adequate prosthesis-defect relationship during the postsurgical period. After complete wound healing and defect size seem stabilized, a more sophisticated prosthesis may be constructed using a cobalt-chrome cast base and exacting techniques to restore maximum tooth occlusion, phonation, and deglutition (Fig. Ie).
CURRENT PRACTICES IN MAXILLOFACIAL PROSTHETICS
789
Mandibular repositioning prostheses must be included in management of intraoral defects. There are two types, the guide plane prosthesis and the guide flange prosthesis. The former is an inclined plane placed on a maxillary or palatal prosthesis so that its slope causes the deviated mandibular teeth to slide up the plane into occlusion on the side opposite the defect (Fig. 2A). The latter, or guide flange, is made to fit intimately on the mandibular teeth and provides an upright flange which originates on the buccal aspect of the prosthesis and is directed superiorly so as to engage the buccal surfaces of the maxillary teeth and thus guide the mandibular teeth into occlusion on the side opposite the defect (Fig. 2B, C). These prostheses are also provided as soon after surgery as the patient can tolerate manipulative procedures such as impression making or prosthesis management. Since scar contracture may cause permanent deviation and greater postoperative morbidity, use of these prostheses combined with a proper and maintained exercise program is strongly recommended. Through strict adherence to this regime, many patients never require a more definitive type of prosthesis. If a patient does become dependent on a mandibular repositioning prosthesis, more sophisticated materials and techniques are employed to ensure long-term function (Fig. 2D, E).
'Jf
Figure 2. Mandibular repositioning prostheses. A. Guide plane prosthesis. B and C, Guide flange prosthesis. Figure 2 continued on following page.
790
JAMES
Figure 2 Continued.
B.
LEPLEY
D and E, Prostheses for long-term use.
Extraoral Prostheses Extraoral or externally worn prostheses may be ocular, oculofacial, nasal, aural, or a combination of the foregoing (Fig. 3). These prostheses serve as functional or cosmetic substitutes for plastic or reconstructive surgical procedures for reasons previously mentioned. Materials used in the fabrication of these prostheses may include methylmethacrylate, plasticized forms of methylmethacrylate and polyvinyl chloride resin, silicones, and polyurethane. Table 1 demonstrates the capability of these five commonly used polymers to fulfill the requirements of an ideal prosthesis material. Polyurethane, although seeming to meet the ideal qualifications in all respects, has had shortcomings which hopefully will be eliminated when the techniques of fabrication are perfected. By varying the choice of materials, an acceptable prosthesis may be fabricated in as little time as 4 hours, or up to several weeks. The foregOing implies a high degree of expertise on the part of the maxillofacial prosthodontist and highly skilled members on his technical team. Summary The maxillofacial prosthodontist has an array of skills and materials which demonstrates his capabilities as a member of the patient manage-
CURRENT PRACTICES IN MAXILLOFACIAL PROSTHETICS
Figure 3. Patient requiring combination intraoral-extraoral prosthesis.
791
792
JAMES
B.
LEPLEY
Table 1. Capabilities of Five Commonly Used Polymers as Prosthesis Material ~
z
~ ~
~
;:J
Z 0 r..>
IDEAL MATERIAL PROPERTIES
~ ~
~ Z ;:J r..>
r..>
6
0 r..>
'"
..:
en
~
f-< ;:J
.:...:
..:I
><
Z
..: :z: f-<
~ ~
:;:
;:J
><
><
~ :z:~
..:I
0
..:I
0
:i:f-< ~
::;: ..:I
~
f-<
>< ..: ..:I
:z: f-< ~
~
::;: r..>..:
'"
'"
1. Tissue receptivity - nontoxic or nonallergenic
+
+
+
+
±
2. Retain accurate form and detail
+
+
±
+
+
3. Translucent
0
±
+
+
±
4. Accept both intrinsic and extrinsic coloring
+
+
+
+
+
5. Durable and weather-resistant
+
+
0
+
±
6. Stain-resistant
+
+
0
+
+
7. Flexible-from 40" to 1400F
±
±
±
+
0
8. Adherence to skin securely during facial movements
±
+
+
+
0
9. Fine marginal contact with edge strength
±
+
±
+
+
"See text for qualification of positive reports.
ment team for those with defects of the head and neck regions. The ultimate goal of this team must be the survival of the patient with restoration to a high degree of the quality of life. Memorial Sloan-Kettering Cancer Center 1275 York Avenue New York, New York 10021
Current Practices in Maxillofacial Prosthetics
James B. Lepley, D.D.S.*
Maxillofacial prosthetics is the art and science of anatomic, functional, or cosmetic reconstruction, by means of nonliving substitutes, of those regions in the maxilla, mandible, and face that are missing or defective because of surgical intervention, trauma, pathology, or developmental or congenital malformation. Since recorded time there is evidence of man's desire to overcome physical deformity, especially about the face and head. Ancient Chinese fabricated missing portions of the face from resins and restored missing eyes with metallic, lacquered globes. Egyptian mummies have been discovered with missing eyes replaced by stone and mosaic replicas. The Romans document the "maker of the eye" as well as "the doctor of the eye." Carried down to modern times is the custom practiced by nomadic desert tribes of severing the hand of a thief. These victims often try to restore the missing hand by fashioning a replacement from animal bones and skin, and vegetable dyes for coloring. Modern man is equally concerned with overcoming physical deformity. No longer is quantity of survival the only measure of success in care of the afflicted; quality of survival has achieved equal import. In his role as a functioning member of the management team of patients with acquired or congenital defects of the head and neck, the maxillofacial prosthodontist is dedicated to the maximum restoration of these individuals to as nearly a normal way of life as possible. Recognizing the fact that reconstruction of a defect with functioning, living tissue is the ultimate and most desired goal, prosthetic restoration is indicated when the defect cannot be successfully bridged with viable tissues, when the age or physical condition of the patient negates surgical reconstruction, and when factors of time and expense contraindicate lengthy and frequent hospitalization, as an intermediate restoration during reconstructive surgical efforts. Perhaps of prime importance is the fact that defects need frequent and continuous follow-up inspection to detect recurrence of disease or other abnormal changes. Prosthetic reconstruction permits this. '''Chief, Dental Service, Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York
Surgical Clinics of North America- Vol. 54, No.4, August 1974
787
788
JAMES
B.
LEPLEY
* Figure 1. A, Palatal defect to be closed. B, Prosthesis with wrought metal clasps for tooth retention in the unaffected maxillary remnant. C, A more sophisticated prosthesis to restore maximum tooth occlusion, phonation, and deglutition.
Prosthetic restoration of defects about the head and neck may be grouped in two broad categories, namely, intra- and extraoral prostheses. In addition, certain prostheses are constructed which are used only during treatment, such as surgical stents and radiation source carriers. Intraoral Prostheses Intraoral prostheses include obturators to close palatal defects, obturator-speech bulb combinations which not only close bony defects but supply missing soft palate as well, and speech bulb prostheses which only replace missing soft palate structures (Fig. lA). These prostheses may be provided either as an immediate procedure and placed in the defect in the operating room or delivered at such time as surgical packs are removed. These prostheses are usually constructed from methylmethacrylate resin and mayor may not, as indicated, have simple wrought metal clasps for retention if any teeth are remaining in the unaffected maxillary remnant (Fig. IB). Minor adjustments are usually necessary to maintain an adequate prosthesis-defect relationship during the postsurgical period. After complete wound healing and defect size seem stabilized, a more sophisticated prosthesis may be constructed using a cobalt-chrome cast base and exacting techniques to restore maximum tooth occlusion, phonation, and deglutition (Fig. Ie).
CURRENT PRACTICES IN MAXILLOFACIAL PROSTHETICS
789
Mandibular repositioning prostheses must be included in management of intraoral defects. There are two types, the guide plane prosthesis and the guide flange prosthesis. The former is an inclined plane placed on a maxillary or palatal prosthesis so that its slope causes the deviated mandibular teeth to slide up the plane into occlusion on the side opposite the defect (Fig. 2A). The latter, or guide flange, is made to fit intimately on the mandibular teeth and provides an upright flange which originates on the buccal aspect of the prosthesis and is directed superiorly so as to engage the buccal surfaces of the maxillary teeth and thus guide the mandibular teeth into occlusion on the side opposite the defect (Fig. 2B, C). These prostheses are also provided as soon after surgery as the patient can tolerate manipulative procedures such as impression making or prosthesis management. Since scar contracture may cause permanent deviation and greater postoperative morbidity, use of these prostheses combined with a proper and maintained exercise program is strongly recommended. Through strict adherence to this regime, many patients never require a more definitive type of prosthesis. If a patient does become dependent on a mandibular repositioning prosthesis, more sophisticated materials and techniques are employed to ensure long-term function (Fig. 2D, E).
'Jf
Figure 2. Mandibular repositioning prostheses. A. Guide plane prosthesis. B and C, Guide flange prosthesis. Figure 2 continued on following page.
790
JAMES
Figure 2 Continued.
B.
LEPLEY
D and E, Prostheses for long-term use.
Extraoral Prostheses Extraoral or externally worn prostheses may be ocular, oculofacial, nasal, aural, or a combination of the foregoing (Fig. 3). These prostheses serve as functional or cosmetic substitutes for plastic or reconstructive surgical procedures for reasons previously mentioned. Materials used in the fabrication of these prostheses may include methylmethacrylate, plasticized forms of methylmethacrylate and polyvinyl chloride resin, silicones, and polyurethane. Table 1 demonstrates the capability of these five commonly used polymers to fulfill the requirements of an ideal prosthesis material. Polyurethane, although seeming to meet the ideal qualifications in all respects, has had shortcomings which hopefully will be eliminated when the techniques of fabrication are perfected. By varying the choice of materials, an acceptable prosthesis may be fabricated in as little time as 4 hours, or up to several weeks. The foregOing implies a high degree of expertise on the part of the maxillofacial prosthodontist and highly skilled members on his technical team. Summary The maxillofacial prosthodontist has an array of skills and materials which demonstrates his capabilities as a member of the patient manage-
CURRENT PRACTICES IN MAXILLOFACIAL PROSTHETICS
Figure 3. Patient requiring combination intraoral-extraoral prosthesis.
791
792
JAMES
B.
LEPLEY
Table 1. Capabilities of Five Commonly Used Polymers as Prosthesis Material ~
z
~ ~
~
;:J
Z 0 r..>
IDEAL MATERIAL PROPERTIES
~ ~
~ Z ;:J r..>
r..>
6
0 r..>
'"
..:
en
~
f-< ;:J
.:...:
..:I
><
Z
..: :z: f-<
~ ~
:;:
;:J
><
><
~ :z:~
..:I
0
..:I
0
:i:f-< ~
::;: ..:I
~
f-<
>< ..: ..:I
:z: f-< ~
~
::;: r..>..:
'"
'"
1. Tissue receptivity - nontoxic or nonallergenic
+
+
+
+
±
2. Retain accurate form and detail
+
+
±
+
+
3. Translucent
0
±
+
+
±
4. Accept both intrinsic and extrinsic coloring
+
+
+
+
+
5. Durable and weather-resistant
+
+
0
+
±
6. Stain-resistant
+
+
0
+
+
7. Flexible-from 40" to 1400F
±
±
±
+
0
8. Adherence to skin securely during facial movements
±
+
+
+
0
9. Fine marginal contact with edge strength
±
+
±
+
+
"See text for qualification of positive reports.
ment team for those with defects of the head and neck regions. The ultimate goal of this team must be the survival of the patient with restoration to a high degree of the quality of life. Memorial Sloan-Kettering Cancer Center 1275 York Avenue New York, New York 10021