US4402671A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for dental crown removal
Assignee: Individual
•
Filing: 1982-05-17
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Granted: 1983-09-06
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Expires: 2002-05-17
Abstract
Abstract A removal dental crown adapted to be secured by a layer of bonding material to a tooth. The crown has a removable key threadedly secured in a channel formed directly in the crown. The key includes a recess for receiving a tool for removal of the key thereby leaving a threaded channel in the crown. An extractor tool can then be inserted into the threaded channel for engagingly breaking the bonding layer and forcing the crown away from the tooth.
Inventors
- 👤 Robert D. Westerman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 02:26
CPC Classifications
A; A61; A61C; A61C3/00; A61C3/16; A61C5/00; A61C5/70; A61C3/162
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
98 words
A removable dental crown adapted to be secured by a layer of bonding material to a tooth, said crown having a removable key threadedly secured in a channel formed directly in the top portion of the crown and said key forming an integral part of the crown during actual usage of the crown, said key having a recess therein for receiving a tool for the removal of said key thereby leaving a threaded channel in said crown for threadably receiving an extractor tool therein for engagingly breaking said bonding layer and forcing the crown away from the tooth.
Claim 2
Dependent Claim
98 words
A removable dental crown adapted to be secured by a layer of bonding material to a tooth, said crown having a removable key threadedly secured in a channel formed directly in the top portion of the crown and said key forming an integral part of the crown during actual usage of the crown, said key having a recess therein for receiving a tool for the removal of said key thereby leaving a threaded channel in said crown for threadably receiving an extractor tool therein for engagingly breaking said bonding layer and forcing the crown away from the tooth.
Claim 3
Dependent Claim
21 words
A removable dental crown as in claim 1, wherein said key comprises a set screw having a wrench receiving recess therein.
Claim 4
Dependent Claim
21 words
A removable dental crown as in claim 2, wherein said set screw comprises a cylindrical body externally threaded end to end.
Claim 5
Dependent Claim
22 words
A removable dental crown as in claim 3, wherein said recess comprises a counter-sunk bore axially extending into an upper end thereof.
Claim 6
Dependent Claim
23 words
A removable dental crown as in claim 4 and further comprising a channel axially extending into a lower end of said cylindrical body.
Claim 7
Dependent Claim
28 words
A removable dental crown as in claim 3, wherein one end of said cylindrical body is subsequently flat and the other end is shaped to a suitable configuration.
Claim 8
Dependent Claim
31 words
A removable dental crown as in claim 3, wherein an upper end of said cylindrical body extends to the surface of the crown and conforms in shape to the crown configuration.
Claim 9
Dependent Claim
26 words
A removable dental crown as in claim 4, wherein said recess extends to a depth of at least 1/2 of the height of the cylindrical body.
Claim 10
Independent Claim
65 words
A method for removing a dental crown secured by a layer of bonding material to a tooth, said method comprising the steps of: forming a cylindrical channel directly into the dental crown; tapping the channel in the crown using a non-tapered tap; removing the tap, and threading extractor tool into the tapped channel until the bonding layer breaks and frees the crown from the tooth.
Claim 11
Independent Claim
65 words
A method for removing a dental crown secured by a layer of bonding material to a tooth, said method comprising the steps of: forming a cylindrical channel directly into the dental crown; tapping the channel in the crown using a non-tapered tap; removing the tap, and threading extractor tool into the tapped channel until the bonding layer breaks and frees the crown from the tooth.
Claim 12
Dependent Claim
60 words
A method as in claim 9, and further comprising the steps of inserting a key into the tapped channel and maintaining it in place as an integral portion of said crown during actual usage of the crown and until removal of the crown is desired, and removing the key so that the extractor tool can be threaded into the channel.
Claim 13
Dependent Claim
37 words
A method as in claim 10, wherein said key comprises a set screw having a recess, and wherein said step of removing the key comprises inserting a key wrench into the recess and withdrawing the set screw.
Claim 14
Dependent Claim
25 words
A method as in claim 9, and further comprises the step of casting a set screw housing into the dental crown to form said channel.
Claim 15
Dependent Claim
38 words
A method as in claim 10, wherein said key extends to the occlusal surface of the crown and further comprising the step of adjusting the occlusal configuration including said key, as is needed to fit the patient requirements.
Claim 16
Dependent Claim
29 words
A method as in claim 10, wherein said key is inserted so that it extends to the tooth and is embedded therein for retaining the crown to the tooth.
References Cited (Backward Citations)
US2591451A
Cited
US2640266A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-09-05 | 1987-03-07 | 1987-09-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-09-05 | 1991-03-07 | 1991-09-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-09-05 | 1995-03-07 | 1995-09-06 | $7700.00 | Window Closed / Lapsed |