Matrixing strategies for the
anterior and facial surfaces
by Drs. Arthur R. Volker, Pantelis Kouros and Serhat Köken
The purpose of a matrix is to function as a shape-former
and facilitate the placement of materials such as amalgam
or composite resin. Many options are available in terms of
material selection and scope; this article will discuss various
matrixing options as applied to anterior or facial composite restorations.
Metal and plastic matrices will be discussed, specifically, as well as
sectional and “full-contour” ones.
Plastic matrices: Mylar matrices are a ubiquitous
part of every clinician’s armamentarium. Their many
advantages include malleability, the ability to cure
through, and the resultant highly polished surface when
cured against composite.1,2 Issues can arise in areas of
tight or irregular contacts, where the thin Mylar may
not be able to traverse or may warp. Also, the thin strip
may not hold its shape as readily as a metal matrix,
though there are protocols to negate this effect,3 and
stiffer anatomical Mylar matrices are available.
Metal matrices: Long used in posterior restorations,
metal matrices are increasingly used in the anterior region.
One reason is their stiffness, which will allow them to
maintain their shape when placed. Additionally, metal
matrices are often easier to place interproximally than
plastic matrices. However, light will not pass through
these matrices, so care must be taken when curing the
composite restoration to ensure full polymerization.
Table 1
Matrix style
Anterior and facial matrices are primarily used in
two shape styles:
- A sectional matrix is used to restore a specific
portion of the tooth, such as a single proximal
surface.
- A “full-contour” matrix, in this context, refers
to one that wraps around both proximal surfaces
and encompasses the cervical portion of the
tooth. These matrices can be used to restore
proximal surfaces, as well as other restorations
such as Class Vs and full-contour veneers.
The use of heated composite with an injection
molding technique has been shown for both sectional
matrices4 and full-contour ones.5 Advantages to employing
heated composite include increased cavity adaptation,
degree of conversion and reduced polymerization
shrinkage.6 There are a number of heating units on
the market, including the HeatSync (Bioclear), Calset
(AdDent) and the Compex HD (AdDent).
Table 1 lists some advantages and disadvantages
with various types of plastic and metal matrices. The
following clinical vignettes demonstrate situations where
a particular matrix may be utilized.
Example with plastic sectional matrix
The patient, in his late 30s and in good health,
was unhappy with the black triangles present in his
lower anterior (Fig. 1). He had been under the care of
a periodontist for the past several years.
Because the area to be filled was very small, Bioclear
matrices were chosen. A heavy, latex-free rubber dam
was placed, and biofilm was removed with aluminum
trihydroxide (Fig. 2). Small black triangle matrices
(BT Matrices, Bioclear) were seated into the sulcular
area (Fig. 3).
Using a combination of uncured bonding agent,
heated flowable (Filtek Supreme Ultra Flowable, 3M)
and heated paste composite (Filtek Supreme Ultra,
3M), the matrices were filled from #22 to #27 (Fig. 4).
Fig. 5 demonstrates the two-day follow-up.
Fig.4
Fig.5
Example with metal sectional matrix
The patient, 35 years old and in good general health,
presented with large, failing composites on the central
incisors, as well as a crown that needed to be placed
on #10 (Fig. 6).
A rubber dam with floss ligatures was placed, and
a stent was used to help create the palatal extent of the
restoration and guide layering of composite (Fig. 7).
A nanohybrid composite (Micerium, Avengo,
Italy) was used to build the composite toward the
facial, and a sectional matrix (Tor VM, Moscow) was
placed interproximally. The curvature of the matrix
approximated the proximal surface, and a thin layer of
composite was used to replicate this area (Fig. 8). Fig. 9
shows the area after curing of this composite layer.
Subsequent layers were then added until the restoration
was complete (Fig. 10).
Fig. 11 demonstrates a five-year follow-up.
Example with plastic full-contour matrix
The patient, in her early 40s and in good health,
was unhappy with the appearance of her front teeth.
Caries were noted on Teeth #8, 10 and 11 (Fig. 12).
Because existing contacts were present, a flat Mylar
matrix was employed. Contacts were smoothed with an
interproximal sander (Contact EZ, DirectaDentalGroup).
The Mylar was inserted into the sulcus at an approximate
45-degree angle and wood wedges were inserted to
control unwanted ingress of material (Fig. 13). This
angle created tension to slightly retract the gingival
tissue, negating the need for retraction cord.
A small amount of heated flowable composite (Filtek
Supreme Ultra Flowable) was placed (Fig. 14), but not
cured. This was followed by heated paste composite
(Filtek Supreme Ultra, Fig. 15). A hand instrument
(OptraSculpt, Ivoclar Vivadent) was used to further
adapt the composite to the tooth (Fig. 16).
Fig. 17 demonstrates the final result.
Example with metal full-contour matrix
The patient, in his mid-50s and in good health,
presented with occlusal issues and multiple cervical
lesions and wear, and complained of pain localized to #21.
Because strong and broad contacts existed, a flat
Mylar might proved too fragile to pass through, and
a metal Tofflemire matrix (Slick Bands, Garrison) was
selected. Before placement, the Tofflemire was modified
to provide a more anatomic contour.7
The matrix was placed into the sulcus at a slight
facial angle with wedges (Fig. 18). To help stabilize the
matrix, wooded wedges were placed, and the tooth was
etched (Fig. 19) and bonded.
A heated flowable composite was placed but not
cured (Fig. 20); then, a heated microfilled composite
(Renamel Microfill, Cosmedent) was injected into
the area (Fig. 21). After curing, excess composite was
removed, and the restoration polished (Fig. 22).
Fig. 23 shows the immediate postoperative result.
Conclusion
Whether composed of metal or plastic, matrices are available for any clinical situation and
will help clinicians obtain their and their patients’ desired restorative outcome.
References
1. Bansal, K., Gupta, S., Nikhil, V., Jaiswal, S., Jain, A., and Aggarwal, N. “Effect of Different Finishing and Polishing Systems on the Surface
Roughness of Resin Composite and Enamel: An In Vitro Profilometric and Scanning Electron Microscopy Study.” Int J Appl Basic Med Res. 2019
Jul-Sep;9(3): 154–158.
2. Uçtas¸li, MB, Arisu, HD, Omürlü, H., Eligüzelg?lu, E., Ozcan, S., and Ergun, G. “The Effect of Different Finishing and Polishing Systems on the
Surface Roughness of Different Composite Restorative Materials.” J Contemp Dent Pract. 2007 Feb 1;8(2): 89–96.
3. Belvedere, PC. “Full-Mouth Reconstruction of Bulim-Ravaged Teeth Using Direct Composites: A Case Presentation.” Dent Today. 2009
Jan;28(1): 126–131.
4. Clark, D. “Restoratively Driven Papilla Regeneration: Correcting the Dreaded ‘Black Triangle.’ ” Tex Dent J. 2008 Nov;125(11): 1112–15.
5. Belvedere, PC, and Lambert, DL. “Creating the ‘Perfect’ Class V Composite: The Matrix Is Key.” Dent Today. 2016 Feb;35(2): 104–107.
6. Lopes, LCP, Terada, RSS, Tsuzuki, FM, Giannini, M., and Hirata, R. “Heating and Preheating of Dental Restorative Materials: A Systematic
Review.” Clin Oral Investig. 2020 Dec;24(12): 4225–35.
7. Volker, AR, and El-Sayed Abdulhady, M. “The Use of a Modified Tofflemeyer Matrix for the Restoration of Cervical Lesions” The GP. In print.
Dr. Pantelis Kouros practices
in Thessaloniki, Greece.
Dr. Serhat Köken practices in Istanbul, Turkey.
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