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Technique for cranioplasty prosthesis fabrication
Technique
for craniqdasty
Richard D. Jordan, D.D.S., MS.,” D.D.S.*** University
of North
Carolina,
progthesis
James T. White,
School
of Dentistry,
Chapel
D.D.S., M.S.,** Hill,
fabrication and Nathan Schupper,
N. C.
1
his article describes a technique for fabricating a clear acrylic resin prosthesis for a cranial repair. The technique employs presurgical fabrication benefitting both the patient and the neurosurgeon.
TECHNIQUE 1. Shave the scalp to insure an accurate registration of the borders of the defect. 2. Palpate the borders of the defect and mark them with an indelible pencil (Figs. 1 to 3). 3. Mark the anterior and superior aspects of the defect for proper orientation. 4. Adjust a cardboard-gummed tape retainer to confine the impression material to the region to be recorded. An adequate margin beyond the borders of the defect should be included (Fig. 4). 5. Use alginate (irreversible hydrocolloid) impression material to make the impression. Twice the recommended amount of water-powder ratio is used. 6. Embed cotton roils in the setting hydrocolloid to provide retention for a reinforcing matrix. 7. Use quick-setting plaster of Paris to reinforce the hydrocolloid impression. 8. Carefully remove the reinforced impression from the patient’s head, box with gummed wrapping tape, and pour in vacuum-mixed stone (Fig. 5). The indelible marking on the scalp will transfer from the scalp to the irreversible hydrocolloid impression and then from the impression to the working cast (Fig 6). The markings are not as concise as originally placed. The center of the line is assumed to be the original
Fig. 1. Palpating and marking the defect on si patient.
border.
Fig. 2. Borders Presented
as a table
clinic
at the American
Prosthodontic
ety. *Assistant Professor, Department of Fixed Prostbodontics. **Assistant Professor, Department of Removable Prosthodontics. ***Associate Professor, Department of Removable Prosthodontics.
230
AUGUST
1978
VOLUME
40
NUMBER
2
of the defect
marked
on a
Soci-
9. Carve a 4 mm deep step on the defect the boundary line (Fig. 6). 10. Mark a 5 mm margin beyond the b score.Cut an outer shelf to a depth of 2.m a flange in the final prosthesis.
0022-3913/78/0240-02%00.40/0Q
1978 The C V. M&y
Co.
CRANfOPLASTY
PROSTHESIS FABRICATION
Fig. 5. Simulated boxed impression. A, Cardboard tray, B, Gummed tape, C, Alginate (irreversible hydrocolloid) impression. Note the indexing mark {aruozcl)to aid in orienting the cast and pattern.
Fig. 3. Tracing of the borders on the patient.
Fig. 6. The working cast with indelible markings. The step is carved on the defect side. A s mm margin is marked beyond the border (urrows).
Fig. 4. Retainer is positioned to confine the impression material. 11. Wax the depressed central portion of the working cast to establish appropriate contour. 12. Prepare the working cast for duplication by adapting a strip of gummed tape to the border after soaking the cast in water for 5 minutes. A large rubber band enhances the seal (Fig. 7). 13. Make a reversible hydrocolloid impression. 14. Separate the hydrocolloid impression from the working cast, box with gummed wrapping tape, and pour in vacuum-mixed artificial stone (Fig. 8). 15. Add baseplate wax to the duplicated cast to the desired contours. The contours should be harmonious with the morphology adjacent to site of the defect (Fig. 9). 16. Flask the pattern on the cast in the usual manner for dentures. A high-grade clear acrylic resin is used for the cranial plate. Stone-acrylic resin
THE JOURNAL OF PROSTHETIC
DENTISTRY
Fig. 7. The corrected working cast is prepared for duplication. separation is accomplished by adapting tinfoil or applying tinfoil substitute. To insure elimination of all free monomer and complete cure, the resin is processed at 168” F for 12 hours and then boiled for 30 minutes.
231
JORDAN,
Fig. 8. Duplicated
cast.
Fig. 11. Internal surface of prosthesis. border that is used for support (arrow).
Fig, 12. Inlay-onlay Fig. 9. The waxed defect.
prosthesis
restores
WHITE,
contour
to the
characteristics
AND
SCHUPRR
Note the lip at the
of the
prosthesis
(arrowsj.
both ends with a flame-shaped bur (Fig 10). Fluid exchange and ingrowth of connective tissue +e permitted through the evenly spaced holes and allow for needed decompression and firm fixation of the prosthesis. The prosthesis is polished (Figs. 11 and 12). 18. Sterilize the prosthesis with ethylene oxide gas or by soaGing in Zephiran chloride* or C5dex.t SUMMARY
Fig. 10. The processed prosthesis
on the working
cast.
17. Bench-cool the prosthesis, deflask, and trim with arbor bands to a feather edge. ‘I’he scored border on the working cast aids in identifying the intended border of the prosthesis. Drill holes with a No. 8 round bur through the prosthesis and bevel at 232
A technique has been described for fabrication af a cranioplasty prosthesis. The primary advantage of this technique is the duplication of the altered working cast. The technique also permits excefknt reproduction of cranial contours and a positive seat of the prosthesis on the outer table of the skull. The disadvantage is the time involved in the duplic&ng procedure. *Winthrop, TArbrook,
New York, Inc., Arlington,
N. Y. ‘rexas
AUGUST
1978
VOLUME
40
N-Z
CRANIOPLASTY
PROSTHESIS
FABRICATION
REFERENCES 1. 2. 3. 4.
5. 6. 7. 8.
9.
Koss, P., and Jelsma, F.: Experiences with acrylicplastic for cranioplasties. Am Surg 26:519, 1960. Spencer, W. T.: Form-fitting cranioplasty. J Neurosurg 11:219, 1954. Elkins, C. W., and Cameron, J. E.: Cranioplasty with acrylic plates. J Neurosurg 3:199, 1946. Small, J. M., and Graham, M. P.: acrylic resin for the closure of skull defects, preliminary report. Br J Surg 33:106, 1945. Trapozzano, V. N., Orant F. C., and Spitz, E. B.: Acrylic cranioplasty. Oral Surg 1:815, 1940. Brown, K. E.: Fabrication of an alloplastic cranioimplant. J PROSTHET DErn 24:213, 1970. Cozza, V.J.: A technique for the accurate fit of a cranioimplant. J Hosp Dent Prac 5:75, 1971. Reuben, J., and Cleminshaw, II.: Cranioplasty prosthesis. S African Med J 38: 111, 1964.
ARTICLES
10. 11.
12.
Firtell, D. N., Moore, D, J., and Bartlett. S. 0.: Radiographic grid for contouring cranial prostheses. J PKOCTHE? DE.u~ 25:439, 1971. Schupper, N.: Cranioplasty prostheses for replacement of cranial bone. J PROSTHET DENT 19594, 1968. Guirdjian, E. S., Webster, J. E., and Brown, J. (Z.: Impression technique for construction of large skull defects. Surgery 14:876, 1943. Polisar, R. S., and Cook, A. W.: Use of polyethylene in cranial implants. J PRO~THET DENT 29310, IWl.
Reprint requests to: DR.
RICAARD
D. JORDAN
UNIVERSI~ OF NORTH SCHWI. OF DENTISTRY CHAPEL
TO APPEAR IN FUTURE
CAROLINA
N. (2. 27514
HILI.,
ISSUES
A new semiadjustable articulator. Part IV. Hisatoshi
Tanaka,
D.D.S.,
MS.,
and
Israel
M.
Finger,
B.D.S.,
M.S.
A technique for restoring abutments for removable partial dentures Kenneth
W. Teppo,
D.D.S.,
M.S.,
and
Franklin
W.
Smith,
D.D.S.,
MS.
Denture esthetics is more than tooth selection Francis
S. Tautin,
D.D.S.
The vertical displacement of distal-extension techniques Farhad
Vahidi,
Modifying Roberto
von
D.M.D.,
ridges by different impression
M.S.D.
tray materials to improve working qualities Krammer
K.,
Cir.Dent.
Instrumentatiltlbn for placement of vitreous carbon endosseous implants Ronald
Voss,
D.D.S.,
and
Dale
E. Grenoble,
Ph.D.
An evaluation of asymmetry in TMJ radiographs Lawrence
THE JOURNAL
A. Weinberg,
OF PROSTHETIC
DENTISTRY
D.D.S.,
M.S.
233
for craniqdasty
Richard D. Jordan, D.D.S., MS.,” D.D.S.*** University
of North
Carolina,
progthesis
James T. White,
School
of Dentistry,
Chapel
D.D.S., M.S.,** Hill,
fabrication and Nathan Schupper,
N. C.
1
his article describes a technique for fabricating a clear acrylic resin prosthesis for a cranial repair. The technique employs presurgical fabrication benefitting both the patient and the neurosurgeon.
TECHNIQUE 1. Shave the scalp to insure an accurate registration of the borders of the defect. 2. Palpate the borders of the defect and mark them with an indelible pencil (Figs. 1 to 3). 3. Mark the anterior and superior aspects of the defect for proper orientation. 4. Adjust a cardboard-gummed tape retainer to confine the impression material to the region to be recorded. An adequate margin beyond the borders of the defect should be included (Fig. 4). 5. Use alginate (irreversible hydrocolloid) impression material to make the impression. Twice the recommended amount of water-powder ratio is used. 6. Embed cotton roils in the setting hydrocolloid to provide retention for a reinforcing matrix. 7. Use quick-setting plaster of Paris to reinforce the hydrocolloid impression. 8. Carefully remove the reinforced impression from the patient’s head, box with gummed wrapping tape, and pour in vacuum-mixed stone (Fig. 5). The indelible marking on the scalp will transfer from the scalp to the irreversible hydrocolloid impression and then from the impression to the working cast (Fig 6). The markings are not as concise as originally placed. The center of the line is assumed to be the original
Fig. 1. Palpating and marking the defect on si patient.
border.
Fig. 2. Borders Presented
as a table
clinic
at the American
Prosthodontic
ety. *Assistant Professor, Department of Fixed Prostbodontics. **Assistant Professor, Department of Removable Prosthodontics. ***Associate Professor, Department of Removable Prosthodontics.
230
AUGUST
1978
VOLUME
40
NUMBER
2
of the defect
marked
on a
Soci-
9. Carve a 4 mm deep step on the defect the boundary line (Fig. 6). 10. Mark a 5 mm margin beyond the b score.Cut an outer shelf to a depth of 2.m a flange in the final prosthesis.
0022-3913/78/0240-02%00.40/0Q
1978 The C V. M&y
Co.
CRANfOPLASTY
PROSTHESIS FABRICATION
Fig. 5. Simulated boxed impression. A, Cardboard tray, B, Gummed tape, C, Alginate (irreversible hydrocolloid) impression. Note the indexing mark {aruozcl)to aid in orienting the cast and pattern.
Fig. 3. Tracing of the borders on the patient.
Fig. 6. The working cast with indelible markings. The step is carved on the defect side. A s mm margin is marked beyond the border (urrows).
Fig. 4. Retainer is positioned to confine the impression material. 11. Wax the depressed central portion of the working cast to establish appropriate contour. 12. Prepare the working cast for duplication by adapting a strip of gummed tape to the border after soaking the cast in water for 5 minutes. A large rubber band enhances the seal (Fig. 7). 13. Make a reversible hydrocolloid impression. 14. Separate the hydrocolloid impression from the working cast, box with gummed wrapping tape, and pour in vacuum-mixed artificial stone (Fig. 8). 15. Add baseplate wax to the duplicated cast to the desired contours. The contours should be harmonious with the morphology adjacent to site of the defect (Fig. 9). 16. Flask the pattern on the cast in the usual manner for dentures. A high-grade clear acrylic resin is used for the cranial plate. Stone-acrylic resin
THE JOURNAL OF PROSTHETIC
DENTISTRY
Fig. 7. The corrected working cast is prepared for duplication. separation is accomplished by adapting tinfoil or applying tinfoil substitute. To insure elimination of all free monomer and complete cure, the resin is processed at 168” F for 12 hours and then boiled for 30 minutes.
231
JORDAN,
Fig. 8. Duplicated
cast.
Fig. 11. Internal surface of prosthesis. border that is used for support (arrow).
Fig, 12. Inlay-onlay Fig. 9. The waxed defect.
prosthesis
restores
WHITE,
contour
to the
characteristics
AND
SCHUPRR
Note the lip at the
of the
prosthesis
(arrowsj.
both ends with a flame-shaped bur (Fig 10). Fluid exchange and ingrowth of connective tissue +e permitted through the evenly spaced holes and allow for needed decompression and firm fixation of the prosthesis. The prosthesis is polished (Figs. 11 and 12). 18. Sterilize the prosthesis with ethylene oxide gas or by soaGing in Zephiran chloride* or C5dex.t SUMMARY
Fig. 10. The processed prosthesis
on the working
cast.
17. Bench-cool the prosthesis, deflask, and trim with arbor bands to a feather edge. ‘I’he scored border on the working cast aids in identifying the intended border of the prosthesis. Drill holes with a No. 8 round bur through the prosthesis and bevel at 232
A technique has been described for fabrication af a cranioplasty prosthesis. The primary advantage of this technique is the duplication of the altered working cast. The technique also permits excefknt reproduction of cranial contours and a positive seat of the prosthesis on the outer table of the skull. The disadvantage is the time involved in the duplic&ng procedure. *Winthrop, TArbrook,
New York, Inc., Arlington,
N. Y. ‘rexas
AUGUST
1978
VOLUME
40
N-Z
CRANIOPLASTY
PROSTHESIS
FABRICATION
REFERENCES 1. 2. 3. 4.
5. 6. 7. 8.
9.
Koss, P., and Jelsma, F.: Experiences with acrylicplastic for cranioplasties. Am Surg 26:519, 1960. Spencer, W. T.: Form-fitting cranioplasty. J Neurosurg 11:219, 1954. Elkins, C. W., and Cameron, J. E.: Cranioplasty with acrylic plates. J Neurosurg 3:199, 1946. Small, J. M., and Graham, M. P.: acrylic resin for the closure of skull defects, preliminary report. Br J Surg 33:106, 1945. Trapozzano, V. N., Orant F. C., and Spitz, E. B.: Acrylic cranioplasty. Oral Surg 1:815, 1940. Brown, K. E.: Fabrication of an alloplastic cranioimplant. J PROSTHET DErn 24:213, 1970. Cozza, V.J.: A technique for the accurate fit of a cranioimplant. J Hosp Dent Prac 5:75, 1971. Reuben, J., and Cleminshaw, II.: Cranioplasty prosthesis. S African Med J 38: 111, 1964.
ARTICLES
10. 11.
12.
Firtell, D. N., Moore, D, J., and Bartlett. S. 0.: Radiographic grid for contouring cranial prostheses. J PKOCTHE? DE.u~ 25:439, 1971. Schupper, N.: Cranioplasty prostheses for replacement of cranial bone. J PROSTHET DENT 19594, 1968. Guirdjian, E. S., Webster, J. E., and Brown, J. (Z.: Impression technique for construction of large skull defects. Surgery 14:876, 1943. Polisar, R. S., and Cook, A. W.: Use of polyethylene in cranial implants. J PRO~THET DENT 29310, IWl.
Reprint requests to: DR.
RICAARD
D. JORDAN
UNIVERSI~ OF NORTH SCHWI. OF DENTISTRY CHAPEL
TO APPEAR IN FUTURE
CAROLINA
N. (2. 27514
HILI.,
ISSUES
A new semiadjustable articulator. Part IV. Hisatoshi
Tanaka,
D.D.S.,
MS.,
and
Israel
M.
Finger,
B.D.S.,
M.S.
A technique for restoring abutments for removable partial dentures Kenneth
W. Teppo,
D.D.S.,
M.S.,
and
Franklin
W.
Smith,
D.D.S.,
MS.
Denture esthetics is more than tooth selection Francis
S. Tautin,
D.D.S.
The vertical displacement of distal-extension techniques Farhad
Vahidi,
Modifying Roberto
von
D.M.D.,
ridges by different impression
M.S.D.
tray materials to improve working qualities Krammer
K.,
Cir.Dent.
Instrumentatiltlbn for placement of vitreous carbon endosseous implants Ronald
Voss,
D.D.S.,
and
Dale
E. Grenoble,
Ph.D.
An evaluation of asymmetry in TMJ radiographs Lawrence
THE JOURNAL
A. Weinberg,
OF PROSTHETIC
DENTISTRY
D.D.S.,
M.S.
233