Retention and resistance features for complex amalgam restorations.

J. W. Robbins, J. O. Burgess, James B Summitt

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

Although not absolute, there are indications for each of the retention and resistance features described. Amalgapins and circumferential slots have their greatest indication in teeth with short clinical crowns and in cusps that have been reduced 2-3 mm for coverage with amalgam. In these situations, slots provide more resistance than amalgapins and amalgam inserts. When amalgapins or slots are used as the only retention and resistance features, the restoration is susceptible to early fracture during matrix removal. When the technical requirements for placement of vertical pins can be met, they provide excellent retention and resistance form. Vertical pins should be placed at least 0.5 mm inside the dentinoenamel junction, at a depth of approximately 2 mm, and should protrude from the tooth approximately 2 mm. However, there are inherent risks involved with pin placement; these include crazing of tooth structure, perforation into the pulp or periodontium, and weakening of the amalgam restoration over the pins. The use of both vertical and horizontal pins may be limited by inadequate access; in these cases, alternate devices should be used. When a cusp has been reduced and increased resistance is needed, a ledge or peripheral step may be indicated. It must be remembered that this feature will result in a greater display of amalgam and may be esthetically unacceptable on a facial cusp. If esthetic appearance is a factor, horizontal pins may be used to reinforce a remaining facial cusp. Horizontal pins may also be used to splint or tie a remaining cusp to the restoration.(ABSTRACT TRUNCATED AT 250 WORDS)

Original languageEnglish (US)
Pages (from-to)437-442
Number of pages6
JournalThe Journal of the American Dental Association
Volume118
Issue number4
StatePublished - Apr 1989

Fingerprint

Tooth
Periodontium
Splints
Crowns
Esthetics
Equipment and Supplies

ASJC Scopus subject areas

  • Dentistry(all)

Cite this

Robbins, J. W., Burgess, J. O., & Summitt, J. B. (1989). Retention and resistance features for complex amalgam restorations. The Journal of the American Dental Association, 118(4), 437-442.

Retention and resistance features for complex amalgam restorations. / Robbins, J. W.; Burgess, J. O.; Summitt, James B.

In: The Journal of the American Dental Association, Vol. 118, No. 4, 04.1989, p. 437-442.

Research output: Contribution to journalArticle

Robbins, JW, Burgess, JO & Summitt, JB 1989, 'Retention and resistance features for complex amalgam restorations.', The Journal of the American Dental Association, vol. 118, no. 4, pp. 437-442.
Robbins, J. W. ; Burgess, J. O. ; Summitt, James B. / Retention and resistance features for complex amalgam restorations. In: The Journal of the American Dental Association. 1989 ; Vol. 118, No. 4. pp. 437-442.
@article{25081199561f4f94b3b5ac421cd3e8e2,
title = "Retention and resistance features for complex amalgam restorations.",
abstract = "Although not absolute, there are indications for each of the retention and resistance features described. Amalgapins and circumferential slots have their greatest indication in teeth with short clinical crowns and in cusps that have been reduced 2-3 mm for coverage with amalgam. In these situations, slots provide more resistance than amalgapins and amalgam inserts. When amalgapins or slots are used as the only retention and resistance features, the restoration is susceptible to early fracture during matrix removal. When the technical requirements for placement of vertical pins can be met, they provide excellent retention and resistance form. Vertical pins should be placed at least 0.5 mm inside the dentinoenamel junction, at a depth of approximately 2 mm, and should protrude from the tooth approximately 2 mm. However, there are inherent risks involved with pin placement; these include crazing of tooth structure, perforation into the pulp or periodontium, and weakening of the amalgam restoration over the pins. The use of both vertical and horizontal pins may be limited by inadequate access; in these cases, alternate devices should be used. When a cusp has been reduced and increased resistance is needed, a ledge or peripheral step may be indicated. It must be remembered that this feature will result in a greater display of amalgam and may be esthetically unacceptable on a facial cusp. If esthetic appearance is a factor, horizontal pins may be used to reinforce a remaining facial cusp. Horizontal pins may also be used to splint or tie a remaining cusp to the restoration.(ABSTRACT TRUNCATED AT 250 WORDS)",
author = "Robbins, {J. W.} and Burgess, {J. O.} and Summitt, {James B}",
year = "1989",
month = "4",
language = "English (US)",
volume = "118",
pages = "437--442",
journal = "Journal of the American Dental Association",
issn = "0002-8177",
publisher = "American Dental Association",
number = "4",

}

TY - JOUR

T1 - Retention and resistance features for complex amalgam restorations.

AU - Robbins, J. W.

AU - Burgess, J. O.

AU - Summitt, James B

PY - 1989/4

Y1 - 1989/4

N2 - Although not absolute, there are indications for each of the retention and resistance features described. Amalgapins and circumferential slots have their greatest indication in teeth with short clinical crowns and in cusps that have been reduced 2-3 mm for coverage with amalgam. In these situations, slots provide more resistance than amalgapins and amalgam inserts. When amalgapins or slots are used as the only retention and resistance features, the restoration is susceptible to early fracture during matrix removal. When the technical requirements for placement of vertical pins can be met, they provide excellent retention and resistance form. Vertical pins should be placed at least 0.5 mm inside the dentinoenamel junction, at a depth of approximately 2 mm, and should protrude from the tooth approximately 2 mm. However, there are inherent risks involved with pin placement; these include crazing of tooth structure, perforation into the pulp or periodontium, and weakening of the amalgam restoration over the pins. The use of both vertical and horizontal pins may be limited by inadequate access; in these cases, alternate devices should be used. When a cusp has been reduced and increased resistance is needed, a ledge or peripheral step may be indicated. It must be remembered that this feature will result in a greater display of amalgam and may be esthetically unacceptable on a facial cusp. If esthetic appearance is a factor, horizontal pins may be used to reinforce a remaining facial cusp. Horizontal pins may also be used to splint or tie a remaining cusp to the restoration.(ABSTRACT TRUNCATED AT 250 WORDS)

AB - Although not absolute, there are indications for each of the retention and resistance features described. Amalgapins and circumferential slots have their greatest indication in teeth with short clinical crowns and in cusps that have been reduced 2-3 mm for coverage with amalgam. In these situations, slots provide more resistance than amalgapins and amalgam inserts. When amalgapins or slots are used as the only retention and resistance features, the restoration is susceptible to early fracture during matrix removal. When the technical requirements for placement of vertical pins can be met, they provide excellent retention and resistance form. Vertical pins should be placed at least 0.5 mm inside the dentinoenamel junction, at a depth of approximately 2 mm, and should protrude from the tooth approximately 2 mm. However, there are inherent risks involved with pin placement; these include crazing of tooth structure, perforation into the pulp or periodontium, and weakening of the amalgam restoration over the pins. The use of both vertical and horizontal pins may be limited by inadequate access; in these cases, alternate devices should be used. When a cusp has been reduced and increased resistance is needed, a ledge or peripheral step may be indicated. It must be remembered that this feature will result in a greater display of amalgam and may be esthetically unacceptable on a facial cusp. If esthetic appearance is a factor, horizontal pins may be used to reinforce a remaining facial cusp. Horizontal pins may also be used to splint or tie a remaining cusp to the restoration.(ABSTRACT TRUNCATED AT 250 WORDS)

UR - http://www.scopus.com/inward/record.url?scp=0024655043&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0024655043&partnerID=8YFLogxK

M3 - Article

C2 - 2651502

AN - SCOPUS:0024655043

VL - 118

SP - 437

EP - 442

JO - Journal of the American Dental Association

JF - Journal of the American Dental Association

SN - 0002-8177

IS - 4

ER -