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A technique for facilitating pattern fabrication and clinical evaluation in partial auricular defects
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A technique for facilitating pattern fabrication and clinical evaluation in partial auricular defects Himanshi Aggarwal, MDS,a Pradeep Kumar, MDS,b Saumyendra Vikram Singh, MDS,c and Raghuwar Dayal Singh, MDSd
Partial auricular defects are more difficult to restore than complete auricular defects.1 Conventionally, the ear remnants are removed1 and a complete ear prosthesis is fabricated. However, a patient’s unwillingness to undergo surgery may preclude this option. For such patients, pattern formation is difficult and challenging,1,2 because the wax sculpture must relate accurately to both the patient’s defect site and the cast without distortion or modification in transfer.3 Because of its rigidity, undercuts and convolutions in the residual ear make placing and removing the wax pattern impossible without distortion.4,5 This tip describes auricular pattern fabrication and clinical evaluation with a flexible thermoplastic vacuum-formed polyvinyl chloride (PVC) sheet.
4. Carefully remove the PVC sheet from the cast after cutting it into the desired shape, but slightly overextended overall, to facilitate the insertion and removal of the pattern.
PROCEDURE 1. Make an impression of the residual ear and surrounding tissues with conventional materials and procedure.1,3 2. Pour the cast in dental stone or die stone (Kaldent; Kalabhai Karson Pvt Ltd). 3. Adapt a 5×5-inch PVC thermoplastic sheet (SofTray sheets; Ultradent Products Inc) of 1 mm/0.040inch thickness on the cast with a vacuum former machine (Model #P105-U02; Ultradent Products Inc).
Figure 1. Polyvinyl chloride sheet adaptation verified over partial auricular defect.
a
Senior Resident, Department of Prosthodontics, Faculty of Dental Sciences, King George’s Medical University UP, Lucknow, Uttar Pradesh, India. Senior Resident, Department of Prosthodontics, Faculty of Dental Sciences, King George’s Medical University UP, Lucknow, Uttar Pradesh, India. c Associate Professor, Department of Prosthodontics, Faculty of Dental Sciences, King George’s Medical University UP, Lucknow, Uttar Pradesh, India. d Associate Professor, Department of Prosthodontics, Faculty of Dental Sciences, King George’s Medical University UP, Lucknow, Uttar Pradesh, India. b
THE JOURNAL OF PROSTHETIC DENTISTRY
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Volume 113 Issue 5
Figure 3. Invested pattern with polyvinyl chloride sheet.
Figure 2. Auricular prosthesis pattern.
6. Proceed with the remaining steps of conventional pattern fabrication in sculpting wax (G-120; Factor II Inc). 7. Trim the overextended part of the PVC sheet (Fig. 2) and featheredge the margins of the PVC sheet with a carbide bur (#471; DFS-Diamon GmbH) to improve marginal blending.5 8. Invest the pattern along with the PVC sheet (Fig. 3) and process conventionally in silicone after removing the PVC sheet during dewaxing (Fig. 4).1 In this way, the drawbacks associated with conventional partial ear wax patterns can be overcome. The disadvantages of this technique include the need for a vacuum-former machine and the increased cost of the PVC sheet. REFERENCES 1. Beumer J, Zlotolow I. Maxillofacial rehabilitation. 1st ed. St Louis: CV Mosby; 1979. p. 311-71. 2. Andres CJ, Haug SP. Clinical maxillofacial prosthetics. 1st ed. Chicago: Quintessence Publishing Co, Inc; 2000. p. 233-76. 3. Kubon TM, Kurtz KS, Piro JD. Impression procedure for creating a partial auricular prosthesis. J Prosthet Dent 2000;83:648-51. 4. McMillan LC, Darvell BW. Rheology of dental waxes. Dent Mater 2000;16: 337-50. 5. Kumar P, Singh SV, Aggarwal H, Chand P. Incorporation of a vacuum-formed polyvinyl chloride sheet into an orbital prosthesis pattern. J Prosthet Dent 2015;113:157-9.
Figure 4. Dewaxed molds before removal of polyvinyl chloride sheet.
5. Check the adaptation and extension of the PVC base on the patient (Fig. 1) and mark the anatomic reference points on a land area to facilitate pattern fabrication.
THE JOURNAL OF PROSTHETIC DENTISTRY
Corresponding author: Dr Pradeep Kumar Room no. 404 E Gautam Buddha Hostel Chowk, Lucknow 226003 INDIA Email: [email protected] Copyright © 2015 by the Editorial Council for The Journal of Prosthetic Dentistry.
Aggarwal et al
A technique for facilitating pattern fabrication and clinical evaluation in partial auricular defects Himanshi Aggarwal, MDS,a Pradeep Kumar, MDS,b Saumyendra Vikram Singh, MDS,c and Raghuwar Dayal Singh, MDSd
Partial auricular defects are more difficult to restore than complete auricular defects.1 Conventionally, the ear remnants are removed1 and a complete ear prosthesis is fabricated. However, a patient’s unwillingness to undergo surgery may preclude this option. For such patients, pattern formation is difficult and challenging,1,2 because the wax sculpture must relate accurately to both the patient’s defect site and the cast without distortion or modification in transfer.3 Because of its rigidity, undercuts and convolutions in the residual ear make placing and removing the wax pattern impossible without distortion.4,5 This tip describes auricular pattern fabrication and clinical evaluation with a flexible thermoplastic vacuum-formed polyvinyl chloride (PVC) sheet.
4. Carefully remove the PVC sheet from the cast after cutting it into the desired shape, but slightly overextended overall, to facilitate the insertion and removal of the pattern.
PROCEDURE 1. Make an impression of the residual ear and surrounding tissues with conventional materials and procedure.1,3 2. Pour the cast in dental stone or die stone (Kaldent; Kalabhai Karson Pvt Ltd). 3. Adapt a 5×5-inch PVC thermoplastic sheet (SofTray sheets; Ultradent Products Inc) of 1 mm/0.040inch thickness on the cast with a vacuum former machine (Model #P105-U02; Ultradent Products Inc).
Figure 1. Polyvinyl chloride sheet adaptation verified over partial auricular defect.
a
Senior Resident, Department of Prosthodontics, Faculty of Dental Sciences, King George’s Medical University UP, Lucknow, Uttar Pradesh, India. Senior Resident, Department of Prosthodontics, Faculty of Dental Sciences, King George’s Medical University UP, Lucknow, Uttar Pradesh, India. c Associate Professor, Department of Prosthodontics, Faculty of Dental Sciences, King George’s Medical University UP, Lucknow, Uttar Pradesh, India. d Associate Professor, Department of Prosthodontics, Faculty of Dental Sciences, King George’s Medical University UP, Lucknow, Uttar Pradesh, India. b
THE JOURNAL OF PROSTHETIC DENTISTRY
503
504
Volume 113 Issue 5
Figure 3. Invested pattern with polyvinyl chloride sheet.
Figure 2. Auricular prosthesis pattern.
6. Proceed with the remaining steps of conventional pattern fabrication in sculpting wax (G-120; Factor II Inc). 7. Trim the overextended part of the PVC sheet (Fig. 2) and featheredge the margins of the PVC sheet with a carbide bur (#471; DFS-Diamon GmbH) to improve marginal blending.5 8. Invest the pattern along with the PVC sheet (Fig. 3) and process conventionally in silicone after removing the PVC sheet during dewaxing (Fig. 4).1 In this way, the drawbacks associated with conventional partial ear wax patterns can be overcome. The disadvantages of this technique include the need for a vacuum-former machine and the increased cost of the PVC sheet. REFERENCES 1. Beumer J, Zlotolow I. Maxillofacial rehabilitation. 1st ed. St Louis: CV Mosby; 1979. p. 311-71. 2. Andres CJ, Haug SP. Clinical maxillofacial prosthetics. 1st ed. Chicago: Quintessence Publishing Co, Inc; 2000. p. 233-76. 3. Kubon TM, Kurtz KS, Piro JD. Impression procedure for creating a partial auricular prosthesis. J Prosthet Dent 2000;83:648-51. 4. McMillan LC, Darvell BW. Rheology of dental waxes. Dent Mater 2000;16: 337-50. 5. Kumar P, Singh SV, Aggarwal H, Chand P. Incorporation of a vacuum-formed polyvinyl chloride sheet into an orbital prosthesis pattern. J Prosthet Dent 2015;113:157-9.
Figure 4. Dewaxed molds before removal of polyvinyl chloride sheet.
5. Check the adaptation and extension of the PVC base on the patient (Fig. 1) and mark the anatomic reference points on a land area to facilitate pattern fabrication.
THE JOURNAL OF PROSTHETIC DENTISTRY
Corresponding author: Dr Pradeep Kumar Room no. 404 E Gautam Buddha Hostel Chowk, Lucknow 226003 INDIA Email: [email protected] Copyright © 2015 by the Editorial Council for The Journal of Prosthetic Dentistry.
Aggarwal et al