Matching shades of composite to seamlessly blend into the natural color of a tooth can be very difficult, because teeth are polychromatic. It is necessary to match the higher chroma at the gingival one-third as well as the translucent properties of the incisal one-third and still match the middle area of the tooth.
A small or conservative Class III composite usually blends into the tooth and color matching is not an issue. However, with a large Class III composite that has wide-open interproximal decay, shade matching can be very difficult.1 In the following clinical case, I used Omnichroma, a composite material from Tokuyama Dental, that takes on the shade of the surrounding tooth structure.
The 39-year-old patient had recently been placed on blood pressure medication, some of which can cause a decrease in saliva, leading to “dry mouth,” in which the important enzymes in saliva that buffer acids are not available to stop the decay process.2 One unfortunate result in this patient was a rapid rate of tooth decay interproximally on teeth #6–11. At first glance, the teeth didn’t look so bad; however, after looking at the X-rays and viewing the teeth from a side view, the decay was clearly seen. Once the surface enamel was removed, the true extent of the decay was revealed.
Caries control and restoring the teeth to function was accomplished with this one-shade universal composite. Permanent restorations, such as veneers and crowns, can always be done in the future, but the decay must be removed as soon as possible. The restoration of the teeth with a direct composite can be viewed as an aesthetic buildup, and these restorations may last a long time. What the dentist needs to avoid is placing a large number of indirect restorations, then having to redo them six months or a year later. The decay needs to be treated, but most importantly, the reason for the decay must be diagnosed and treated.3
The patient was placed on a short recall and given home fluoride gel and oral hygiene instructions. He was advised to stop the use of sugary sodas, candy and other products. Recurrence of decay on these restored teeth will certainly lead to much more extensive treatment or possible loss of teeth. To ascertain the patient’s ability to resist decay before undergoing extensive and expensive fixed restorations, treatment with composite fillings was decided upon.
These restorations were very large and would normally require several layers of composite to achieve a good color match. Omnichroma allowed for a faster, less complex procedure and resulted in a restoration that matched the natural teeth well. The material uses technology based on structural color, which enables the composite to match the surrounding tooth color. This saves restorative time because a single shade can be used. This material is very sculptable and can be usually applied in one large mass, without slumping, and then light-cured.
Of the many decayed teeth, tooth #8 was restored first because it had the largest carious lesions. Omnichroma Blocker, a supplementary material from Tokuyama Dental, was used to block out dark tooth structure and to prevent shade-matching interference from the open area on the lingual interproximal area (Figs. 1–2).
After the tooth was anesthetized (one carpule of Lidocaine HCl with 1:100,000 epinephrine), the decayed tooth structure was removed. Large decay was removed from the distal-facial and mesial-facial of tooth #8. There was no pulp exposure, but the restoration was very large and very deep. The underlying tooth structure was very dark, and the lingual wall was wide open (Figs. 3–4).
After the decay was removed, the facial margins were beveled to increase the bond strength and to allow for a better color blend from composite to tooth. Then, 35% phosphoric acid (Ultra Etch, Ultradent) was used to etch the enamel and dentin. After rinsing with water, Bond Force (Tokuyama Dental) bonding agent was used. The bonding agent was gently blown until becoming very thin, then light-cured with a Valo curing light (Ultradent).
Omnichroma Blocker was placed in the deep dentin areas and on the palatal area, then light-cured. The opaque white material “blocks out” wide-open areas to the lingual and dark tooth areas. Omnichroma was placed in one large application for the distal and one large application to the mesial. A mylar pull-through technique was used to verify that the composite was pulled all the way through the contact area without any voids.4 After the restoration was sculpted and well adapted, it was light-cured for 20 seconds on both the mesial and distal (Figs. 5–6).
Next, the lingual surface was adjusted, and the bite was checked. The facial surface was initially contoured with a flame-tip diamond bur to achieve a finish close to the final contour. Next, a coarse disc (Sof-Lex XT, 3M) was used to achieve the primary anatomic form. Then, blue and pink rubber cups (Cosmedent) were used to polish the surface. The final high gloss polish was achieved with Cosmedent’s FlexiBuff and Enamelize (Figs. 7–8).5–7
On two subsequent appointments, Teeth #6, 7, 9, 10 and 11 were prepared and restored. Teeth #7, 9 and 10 had a very similar pattern of deep decay that included large mesial, distal and facial composite restorations.
Teeth #7 and 10 had some enamel loss on the lingual, so I used a thin layer of Omnichroma Blocker to help shape the lingual wall and block out possible interproximal shade-matching interference, which would allow the composite to “pick up” the color of the natural enamel better. The mesial and distal areas of teeth #7, 9 and 10 were each filled with one large layer of composite, contoured and light-cured.
Teeth #6 and 11 were filled in a more conventional manner. When the lingual is intact, the blocker material is not needed. On this patient, the surface of the natural teeth displayed slight amounts of surface opacities. If a dentist wants to blend the composite a little better, the outer surface of the composite material could be “scratched” with a diamond bur. Next, the surface is etched, a bonding agent applied, a small amount of white tint applied and cured, and a thin layer of composite material applied over the surface and light-cured. Then the entire restoration can be finished and polished (Figs. 9–13).
Extensive interproximal decay because of loss of salivary flow or dry mouth is a major dental health concern. There are numerous causes for this decrease, including medication needed for treatment of high blood pressure. These patients often need to have immediate treatment. A well-placed and high-quality composite material is a great first treatment approach. Once the decay is removed, patients need to have their diet carefully monitored, use home fluoride and keep their mouth moistened with the regular intake of water.
In this clinical case, the use of a single-shade composite restorative material saved a lot of time and made the whole restorative treatment easier by matching the color of the natural tooth. The hope is that these restorations will last a long time and, at the very least, act as an excellent buildup for an indirect restoration sometime in the future. However, a lot depends on the patient’s ability to brush, floss, keep a strict diet of no sugar and keep the mouth moist with water. As patients get older, sometimes this becomes extremely difficult. It is still best to remove the decay and access the patient’s ability to resist decay before restoring with indirect restorations that may need to be redone in a short period of time.
The patient was very pleased with the first tooth restored and couldn’t wait to get started with the rest. After all six anterior teeth were restored, he was very happy and seemed to be very willing to do whatever it took to save his teeth. He said the teeth looked as if they never had a cavity and looked brand-new.
Fig. 1: The smile view shows interproximal staining and hypocalcifications.
Fig. 2: Dark, extensive decay on the mesial–facial and distal–facial of #8.
Fig. 3: The interproximal decay has been removed, leaving a large space to fill.
Fig. 4: The extent of the decay on
the facial and interproximal of #8.
Fig. 5: The mylar pull-through technique ensures that the composite is taken all the way through the contact area. The area where Omnichroma Blocker was placed to the lingual is shown.
Fig. 6: The mylar strip was used to contour the composite.
Fig. 7: The shade of Omnichroma composite before light-curing.
Fig. 8: Tooth #8 after the restorations have been finished and polished. Notice the accurate color match and how the composite just blends into the tooth.
Fig. 9: The initial decayed enamel removed around #6 and #7.
Fig. 10: The complete removal of decay on #6 and #7.
Fig. 11: The initial decayed enamel removed around #9 and #10.
Fig. 12: A large area of tooth decay was removed around #9 and #10.
Fig. 13: The completed Class III restorations on #6–10.
Fig. 14: The restorations, about seven months after the procedure.
Fig. 15: A close-up view shows nice retention of polish and excellent color stability.
1. Belvedere P, Lambert D. “Successfully Restoring Class III Composites: The Challenge of Deep Subgingival Margins.” Dentistry Today. Sept 1, 2016.
2. “Dry Mouth Symptoms and Causes.” Mayo Foundation for Medical Education and Research (MFMER)
3. “Managing Dry Mouth.” https://doi.org/10.1016/j.adaj.2014.11.019 2015 American Dental Association. Published by Elsevier Inc.
4. Hollar S. “A Prepless Composite Bonding Case.” Dentaltown, October 2009, p. 66.
5. Peyton, James. “Finishing and Polishing Techniques: Direct Composite Resin Restorations.” Practical Periodontics and Aesthetic Dentistry, May 2004, p. 293.
6. Fahl N. “Mastering Composite Artistry to Create Anterior Masterpieces, Part 2.” J Cosmetic Dent. 2010; 26(4):42–55.
7. Manauta J, Salat A. “Layers: An Atlas of Composite Resin Stratification.” Milan. Quintessence Pub.; 2012; 349–375.