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Treatment of alar collapse with nasal prostheses
Treatment of alar collapse with nasal prostheses John C. Davenport, Ph.D., F.D.S.R.C.S.,” David J. Brain, M.B., Ch.B., F.R.C.S., D.L.O.,** and Alan T. Hunt*** The Dental School, Birmingham, England
D
entists may become involved in the provision of prostheses in the field of otolaryngology* because of their specialized knowledge of impression procedures and allied techniques necessary for the fabrication of prostheses. An example illustrating the application of dental techniques to otolaryngologic problems is the construction of alar stents. The primary function of alar stents is to maintain the nasal airway for patients in whom nasal collapse on inspiration causes a significant level of respiratory inconvenience (Fig. 1). Alar collapse may be caused by congenital weakness of the alae, paresis caused by a stroke, and nasal collapse following a maxillectomy. Alar stents may also be used as postsurgical prostheses for patients in whom nasal obstructions caused by fibrous bands in the nasal vestibule have been treated by excision of the fibrous tissue. The prostheses maintain patency of the nasal airway during the healing period. This article describes an impression technique for constructing alar stents developed during the treatment of 10 patients over a 3-year period. An alternative technique has been described by Young.’
IMPRESSION TECHNIQUE The nasal impression is obtained with the patient sitting upright in the dental chair. The only preparation required is a light application of petroleum jelly to the anterior nares to facilitate subsequent removal of the impression. An anesthetic is not required. Using a small metal spatula, one mix of silicone putty is applied in increments to the posterior wall of
*SeniorLecturer,Departmentof Prosthetic Dentistry. **Consultant
Surgeon, Birmingham
Ear, Nose, and Throat Hos-
nital.
***Chief Maxillofacial and Oral Medicine.
0022-3913/81/040435
Technician,
+ 03$00.30/00
Department
of Oral Surgery
1981 The C. V. Mosby Co.
Fig. 1. External nares A, at rest, and 8, on inspiration showing bilateral alar collapse. the vestibule and floor of the nose, to the anterior wall of the vestibule, and completely filling the vestibule (Fig. 2). The pressure applied by the dentist at this stage depends on whether the function of the prosthesis will be to dilate the nostril or simply to support it.
THE JOURNAL
OF PROSTHETIC
DENTISTRY
435
I~AVENPORT,
BRAIN,
AND
HUN-l
Fig. 2. Incremental method for obtaining a silicone putty impression of the vestibule. A, Application to posterior wall and floor of nose. B, Application to anterior wall. C, Filling of vestibule.
Fig. 4. Completed impression of vestibule recording important retentive portions for the prosthesis. A, The floor of the nasal cavity. B, The anterior w&l of the vestibule.
Fig. 3. Putty impression of the vestibule. A, Before trimming. B, After trimming and injecting low-viscosity silicone rubber. When the putty has set, the impression is removed from the nose. The excess material external to the nares is trimmed so that when the putty is reinserted the margin of the nostril can be seen (Fig. 3). The 436
patient’s head is tilted slightly forward. A disposable syringe is loaded with a low-viscosity silicone rubber, and the nozzle is inserted between the. putty impression and lateral wall of the nose. Injection of the sihcone rubber is continued until the materialbegins to flow from the nose. The syringe is then moved slowly around the putty impression until all the surfaces have been covered. The position of the patient’s head along with limiting the volume of injected silicone rubber to about 2 ml restricts the flow of the silicone rubber posteriorly along the floor of the nose. The final prosthesis must be stable to prevent dislodgement from, or into, the nasal cavity. For this reason, the impression should show the following features (Fig. 4): (1) a projecting retentive portion anteriorly which fits into the ventricle of the nasal vestibule, (2) a retentive portion which projects posteriorly into the anterior part of the nasal cavity, APRIL 1981
VOLUME
45
NUMBER
4
ALAR COLLAPSE
Fig. 5. Acrylic resin alar prosthesis showing posteriorsuperior border extending onto floor of nasal cavity. Inferior border lies within margins of external nares so that prosthesis is not visible when worn.
Fig. 7. Use of metal rod to remove alar prosthesis. nasal spaces may require a cast cobalt-chromium alloy splint to ensure adequate strength (Fig. 6).
FITTING
Fig. 6. Alar prosthesis made of cobalt-chromium
and (3) good surface detail walls of the vestibule.
FABRICATION
of the lateral
alloy.
and medial
OF THE PROSTHESIS
The impression is invested in artificial stone in a dental flask. After the impression has been removed from the flask, final correction of the defects in the mold should be carried out before processing the prosthesis in clear, heat-cured acrylic resin. After deflasking, a hole is drilled through the prosthesis to provide an airway. The prosthesis is then trimmed and polished (Fig. 5). Patients with restricted intra-
THE JOURNAL
OF PROSTHETIC
DENTISTRY
THE PROSTHESIS
The patient is trained to orient the prosthesis correctly and to insert and remove the prosthesis from the nose. As a reasonable degree of manual dexterity is needed to cope with these procedures, this requirement should be considered when selecting patients. Removal of the prosthesis may usually be achieved by digital pressure on the side of the nose. However, if the retention is positive, an indentation is made in the inner surface of the prosthesis into which a metal rod can be inserted by the patient to help with removal (Fig. 7). Placement will be easier if the prosthesis is lubricated with a thin layer of petroleum jelly. For some patients, it may be necessary to incorporate a locating mark in the prosthesis to orient it correctly before insertion. A prosthesis designed with a correct inferior border will not normally be visible when worn. We would like to thank Professor H. constructive criticism and Mr. M. Sharland photographs.
R. ‘Tomlin for his and his staff for the
REFERENCE 1.
Young, 24:320,
J. M.: 1970.
Internal
nares prosthesis.
J PROSTHET DENT
Reprintrequests to: DR. JOHN C. DAVENPORT THE DENTAL SCHOOL ST. CHAD’S QUEENSWAY BIRMINGHAM B4 6NN ENGLAND
437
D
entists may become involved in the provision of prostheses in the field of otolaryngology* because of their specialized knowledge of impression procedures and allied techniques necessary for the fabrication of prostheses. An example illustrating the application of dental techniques to otolaryngologic problems is the construction of alar stents. The primary function of alar stents is to maintain the nasal airway for patients in whom nasal collapse on inspiration causes a significant level of respiratory inconvenience (Fig. 1). Alar collapse may be caused by congenital weakness of the alae, paresis caused by a stroke, and nasal collapse following a maxillectomy. Alar stents may also be used as postsurgical prostheses for patients in whom nasal obstructions caused by fibrous bands in the nasal vestibule have been treated by excision of the fibrous tissue. The prostheses maintain patency of the nasal airway during the healing period. This article describes an impression technique for constructing alar stents developed during the treatment of 10 patients over a 3-year period. An alternative technique has been described by Young.’
IMPRESSION TECHNIQUE The nasal impression is obtained with the patient sitting upright in the dental chair. The only preparation required is a light application of petroleum jelly to the anterior nares to facilitate subsequent removal of the impression. An anesthetic is not required. Using a small metal spatula, one mix of silicone putty is applied in increments to the posterior wall of
*SeniorLecturer,Departmentof Prosthetic Dentistry. **Consultant
Surgeon, Birmingham
Ear, Nose, and Throat Hos-
nital.
***Chief Maxillofacial and Oral Medicine.
0022-3913/81/040435
Technician,
+ 03$00.30/00
Department
of Oral Surgery
1981 The C. V. Mosby Co.
Fig. 1. External nares A, at rest, and 8, on inspiration showing bilateral alar collapse. the vestibule and floor of the nose, to the anterior wall of the vestibule, and completely filling the vestibule (Fig. 2). The pressure applied by the dentist at this stage depends on whether the function of the prosthesis will be to dilate the nostril or simply to support it.
THE JOURNAL
OF PROSTHETIC
DENTISTRY
435
I~AVENPORT,
BRAIN,
AND
HUN-l
Fig. 2. Incremental method for obtaining a silicone putty impression of the vestibule. A, Application to posterior wall and floor of nose. B, Application to anterior wall. C, Filling of vestibule.
Fig. 4. Completed impression of vestibule recording important retentive portions for the prosthesis. A, The floor of the nasal cavity. B, The anterior w&l of the vestibule.
Fig. 3. Putty impression of the vestibule. A, Before trimming. B, After trimming and injecting low-viscosity silicone rubber. When the putty has set, the impression is removed from the nose. The excess material external to the nares is trimmed so that when the putty is reinserted the margin of the nostril can be seen (Fig. 3). The 436
patient’s head is tilted slightly forward. A disposable syringe is loaded with a low-viscosity silicone rubber, and the nozzle is inserted between the. putty impression and lateral wall of the nose. Injection of the sihcone rubber is continued until the materialbegins to flow from the nose. The syringe is then moved slowly around the putty impression until all the surfaces have been covered. The position of the patient’s head along with limiting the volume of injected silicone rubber to about 2 ml restricts the flow of the silicone rubber posteriorly along the floor of the nose. The final prosthesis must be stable to prevent dislodgement from, or into, the nasal cavity. For this reason, the impression should show the following features (Fig. 4): (1) a projecting retentive portion anteriorly which fits into the ventricle of the nasal vestibule, (2) a retentive portion which projects posteriorly into the anterior part of the nasal cavity, APRIL 1981
VOLUME
45
NUMBER
4
ALAR COLLAPSE
Fig. 5. Acrylic resin alar prosthesis showing posteriorsuperior border extending onto floor of nasal cavity. Inferior border lies within margins of external nares so that prosthesis is not visible when worn.
Fig. 7. Use of metal rod to remove alar prosthesis. nasal spaces may require a cast cobalt-chromium alloy splint to ensure adequate strength (Fig. 6).
FITTING
Fig. 6. Alar prosthesis made of cobalt-chromium
and (3) good surface detail walls of the vestibule.
FABRICATION
of the lateral
alloy.
and medial
OF THE PROSTHESIS
The impression is invested in artificial stone in a dental flask. After the impression has been removed from the flask, final correction of the defects in the mold should be carried out before processing the prosthesis in clear, heat-cured acrylic resin. After deflasking, a hole is drilled through the prosthesis to provide an airway. The prosthesis is then trimmed and polished (Fig. 5). Patients with restricted intra-
THE JOURNAL
OF PROSTHETIC
DENTISTRY
THE PROSTHESIS
The patient is trained to orient the prosthesis correctly and to insert and remove the prosthesis from the nose. As a reasonable degree of manual dexterity is needed to cope with these procedures, this requirement should be considered when selecting patients. Removal of the prosthesis may usually be achieved by digital pressure on the side of the nose. However, if the retention is positive, an indentation is made in the inner surface of the prosthesis into which a metal rod can be inserted by the patient to help with removal (Fig. 7). Placement will be easier if the prosthesis is lubricated with a thin layer of petroleum jelly. For some patients, it may be necessary to incorporate a locating mark in the prosthesis to orient it correctly before insertion. A prosthesis designed with a correct inferior border will not normally be visible when worn. We would like to thank Professor H. constructive criticism and Mr. M. Sharland photographs.
R. ‘Tomlin for his and his staff for the
REFERENCE 1.
Young, 24:320,
J. M.: 1970.
Internal
nares prosthesis.
J PROSTHET DENT
Reprintrequests to: DR. JOHN C. DAVENPORT THE DENTAL SCHOOL ST. CHAD’S QUEENSWAY BIRMINGHAM B4 6NN ENGLAND
437