Application of a copper band in complex endodontic access

Transcription

Application of a copper band in complex endodontic access
Innovations and ideas
Application of a copper band in complex endodontic access
preparations
YI-YIN LAI 1,3
DONALD CHUNG-FU YU 2
CHIN-PING CHEN 1,3
1
Department of Dentistry, Tri-Service General Hospital, Taipei, Taiwan, ROC.
Division of Endodontics, Department of Dentistry, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada.
3
Graduate Institute of Clinical Dentistry, School of Dentistry, National Defense Medical Center, Taipei, Taiwan, ROC.
2
Complex access in endodontic therapy may compromise proper isolation of the teeth and the sealing
ability of a temporary restoration between appointments. Without proper isolation and pretreatment of
these teeth, particularly badly mutilated ones, the root canal systems may be contaminated, and success
of endodontic treatment can be reduced. Using a copper band to pretreat a broken-down tooth had been
mentioned in the literature; however, none of those reports provided detailed clinical procedures. A
step-by-step technique for using a copper band as pretreatment for endodontic procedures is described
and illustrated, and its advantages are discussed as well. (J Dent Sci, 1(1):44-46, 2006)
Key words: copper band, complex endodontic access preparation, pretreatment.
Endodontic access preparation is complex when
multiple surfaces of a tooth are grossly broken down,
as isolating the tooth becomes very difficult if not
impossible. This situation offers an unfavorable
working condition for dental practitioners. Without
proper placement of a rubber dam, the root canal
system can become contaminated during treatment
and between appointments. Some temporary filling
materials may provide adequate sealing for teeth with
sufficient intact tooth structure, but not for those with
complex access preparations1. Several solutions have
been suggested to pretreat these broken down teeth
such as direct tooth bonding build-up, a temporary
acrylic crown, an orthodontic stainless steel band,
and a copper band. Application of the copper band as
pretreatment is controversial in the endodontic
literature2. Some disagreed with its use because of
potential hazards to the gingivae and periodontal
tissues3, and the restoration may fail following
subsequent endodontic procedures. However, proper
Received: November 14, 2005
Accepted: January 28, 2006
Reprint requests to: Dr. Chin-Ping Chen, Department of Dentistry, TriService General Hospital, No. 325, Chenggong
Road, Sec. 2, Neihu, Taipei, Taiwan 11490, ROC.
44
application of a copper band and adherence to
guidelines can preclude those possible complications.
The purpose of this article is to describe and illustrate
step-by-step procedures for pretreatment using a
copper band and to discuss its advantages.
ARMAMENTARIUM
Crown scissors, contouring pliers, amalgam
condenser, and PKT3.
Step 1. Access cavity preparation
First, all caries, faulty restorations, and
unsupported enamel should be removed, and then the
restorability of the tooth can be evaluated. Sufficient
biological width and ferrule must be assured at this
evaluation, otherwise extraction or crown-lengthening
procedures should be suggested to the patient. Second,
a straight-line access opening is made to remove all
pulpal tissues and debris from the pulp chamber. All
canal orifices should be located and covered with a
small cotton pellet. A colored temporary filling
material (e.g., Cavit) can be used. This facilitates later
reentry into the canals.
Step 2. Copper band selection and pre-fitting
First, a polishing strip is used to relieve both
J Dent Sci 2006‧Vol 1‧No 1
Copper band application
interproximal contacts of the tooth that is about to
undergo endodontic treatment. A copper band should
be selected which is slightly smaller than the
circumference of the middle 1/3 (or high of the
contour) of the clinical crown. Second, this band is
heated in a Bunsen flame until it is cherry red-hot,
then is plunged into a small cup filled with 75%
isopropyl alcohol. Third, this annealed copper band is
pushed down onto the tooth, and a pencil is used to
mark the free gingival margin and the occlusal
surface; then the band is removed. Fourth, crown
scissors are used to trim the marked gingival margin
on the band so that it covers the tooth structure
supragingivally if sufficient tooth structure is present.
In the area has deep caries, the margin should extend
subgingivally onto the natural tooth structure. Now,
the occlusal margin is trimmed as high as the
adjacent teeth without occlusal interference during
lateral and protrusive excursions. Fifth, a V-shaped
notch is cut on the middle buccal side of the occlusal
margin of the band. Both occlusal and gingival
margins of the band are bent inwardly using the
contouring pliers to improve contour adaptation.
Sixth, a fine green stone is used to smooth and polish
the band margins. Seventh, the band is first refitted
onto the tooth to check it, and then it is removed for
cementation.
Step 3. Cementation
After proper moisture isolation, zinc phosphate
(a)
cement is manipulated according to the manufacturer's
instructions except that a thicker mix is recommended
for restorative purposes. The operator can use a
plastic instrument to fill the cavity, while the assistant
simultaneously loads the cement into the band. The
assistant transfers the band to the operator who then
pushes the band onto the tooth with the cement
powdered finger and thumb, and then using a large
amalgam condenser. The amalgam condenser is used
to fold the buccal occlusal V-shaped notch and
festoon the band's gingival margin onto the cervical
area of the tooth with the PKT3 instrument. Excess
cement should be removed after setting.
Step 4. Band removal
The copper band can be left in place to facilitate
later post and core build-up; otherwise, it can easily
be removed with pliers after grooving.
The advantages of copper band application in
complex endodontic access preparations are listed
here:
− Transforms complex endodontic access preparations into a Class I cavity (Figure 1a, b) which
ensures the between-visit sealing quality of some
temporary filling material (e.g., Cavit)4;
− Prevents leakage of saliva and intracanal
medication between appointments;
− Facilitates rubber dam placement for ideal
isolation of the tooth;
− Facilitates reentry of an appropriate access
(b)
Figure 1. (a) Rubber dam in place over the lower first molar with a complex endodontic access preparation. Extensive caries are
located beneath the mesial marginal ridge. In order to take this photograph, a rubber dam was clamped onto the second molar. (b)
Copper band on the lower first molar cemented with zinc phosphate cement. The original complex endodontic access preparation is
now transformed into a simple Class I cavity. The adequate pulp chamber space provides an environment that facilitates cleaning and
shaping procedures.
J Dent Sci 2006‧Vol 1‧No 1
45
Y.Y. Lai, D.C. F. Yu and C.P. Chen.
(a)
(b)
Figure 2. (a) Upper first molar with subgingival caries and complex endodontic access preparation. (b) Properly fitted copper
band, protecting the remaining tooth structure, and preventing the leakage of saliva and intracanal medication between
appointments. Note that the distal proximal contact was restored with the occlusal margin of the band extending to the same level as
the mesial marginal ridge of the second molar.
preparation;
− Prevents an endodontically treated tooth from
fracturing;
− Provides adequate pulp chamber space to facilitate
cleaning and shaping procedures; and
− Provides a realistic assessment of the restorability
of the tooth.
In the case of subgingival decay (Figure 2a, b),
copper band placement might be the first choice
compared to direct tooth bonding material build-up,
a temporary crown, or an orthodontic band. Direct
tooth bonding material build-up might be more
technique-sensitive in such a situation, as subgingival
moisture control is extremely difficult. A temporary
crown requires moderate tooth preparations on an
already mutilated tooth with minimal tooth structure.
Frequently, this allows little possible crown retention.
Furthermore the tooth reference points for working
lengths are often lost. Orthodontic banding requires
46
sufficient supragingival structure; hence its use with
subgingival decay is impossible.
With caution and some skill, a copper band can
be adapted and secured to customarily fit the treated
tooth tightly in all places. It serves as a good interim
restoration and is the pretreatment of choice in
preparation for endodontic treatment.
REFERENCES
1. Anderson RW, Powell BJ, Pashley DH. Microleakage of
temporary restorations in complex endodontic access
preparations. J Endod, 15: 526-529, 1989.
2. Naoum HJ, Chandler NP. Temporization for endodontics. Int
Endod J, 35: 964-978, 2002.
3. Gingell JC, Zeller GG, Whitaker GC. Potential hazards of
copper band utilization. Gen Dent, 6: 500, 1982.
4. Ingle JI, Bakland LK. Temporary coronal filling materials. In
“Endodontics” 5th ed, BC Decker Inc, Hamilton, London, pp.
649-651, 2002.
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