Dan Ward demonstrates how to create natural composite restorations using different layering techniques, materials, and an erbium YAG laser.
Improved materials and instruments help us to produce restorations that are natural looking. Composite systems have been developed that have optical qualities similar to the tooth structure they are replacing (Baratieri et al, 2007).
Composite materials with dark opacity and fluorescence are useful to recreate dentine (Villarroel et al, 2011). Enamel replacing materials with added translucency and opalescence give the outer surface of the tooth a realistic appearance (Blank, 2003). Layering multiple shades with differing hue, chroma, and value can give the tooth a more three-dimensional look (Terry, 2003).
Composites have been developed with differing approaches using two, three, or more layers. Having multiple systems can be beneficial.
Recently a new laser has been introduced at a significantly lower cost allowing it to be incorporated into more dental practices (Figure 1). Being able to quickly prepare teeth often without anaesthesia has been a significant advantage of using hard tissue lasers (Nazemisalman et al, 2015).
Small to medium sized restorations can often be prepared without the use of local anaesthetics. Let’s examine how these new materials and technologies can be used.
Layered restorations
Layered restorations are helpful in the anterior area to emulate the appearance of natural teeth. Restorative materials should mimic the tooth structure they replace.
The deepest part of the restoration should be dark, more opaque and very high in chroma. Unfortunately, there are few dentine shaded composites that truly match dentine. Very intense yellow/brown materials are needed (Dietschi et al, 2006).
One system, which is excellent for matching tooth structure, is aura (Figure 2). The system originally had two materials, a dentine and an enamel replacement material, but an optional middle layer has been added.
This helps to block the intense chroma of the dentine and blend the restoration colour better. It also helps to make the exact thickness of the dentine and enamel shade layers less critical.
The dentine shades do not coincide with any standard shading system but differ in the intensity of the chroma, ranging from Db, D1 to D7. As you build up the restoration, the material should become lighter, more translucent, opalescent, and have smaller filler particles.
The aura eASY system has an optional intermediate layer, which is aura eASY composite AE4. The final enamel layer is a microfill and it comes in three shades. It is translucent and polishes well.
Three-layered composite restorations case presentation
A 15-year-old male presented to the office with peg lateral incisors and twisted maxillary canines (Figure 3). His mother was interested in closing the spaces between his teeth.
The sizes of the teeth were measured and it was determined that the central incisors were of normal size relative to the face. The widths available for the lateral incisors were deemed to be 70% of the frontal view widths of the central incisors. The widths of the maxillary canine teeth were also deemed to be 70% of the frontal view widths of the lateral incisors.
This follows the recommendations of proportional smile design using the RED (‘recurring esthetic dental’) proportion, which states that the frontal view width proportions of the anterior teeth should remain constant as you move distally (Ward, 2001). Figure 4 demonstrates the ability to add to the lateral incisor and the canine and give a well-proportioned smile that matches the face (Ward, 2015).
The surface of the maxillary right canine was lightly roughened using a very fine diamond to areas to be bonded (201.3VF, Premier Dental). The entire surface was etched with phosphoric acid for 20 seconds, washed, and dried thoroughly.
A universal dentine bonding agent was brushed onto the surface for 20 seconds, the solvent evaporated and the area light cured (Universal Bond, Bisco Dental).
The first increment added was the dentine layer. This layer is darker than the desired restoration but more opaque in order to block light from shining through the entire restoration and prevent a grey appearance.
Dentine shade 6 was used since it mimics the shade of the natural dentine (Figure 5). The second increment added was aura eASY composite shade AE2 (Figure 6). White, orange and brown tints were painted over the second increment to characterise and mimic the shade patterns of the adjacent teeth (shade modification tints, SDI).
Finally, an enamel shade layer E-1 was added to cover the entire restoration and build to full contour (Figure 7). The restoration was shaped using diamonds and finishing carbides. Finishing and polishing was completed for the canine.
The process was completed for the right maxillary lateral incisor (Figure 8). Then the left canine and lateral incisor were restored in a similar fashion (Figure 9).
Erbium YAG lasers
Erbium lasers deliver pulsed energy onto the water, containing surface of the tooth and the water is vaporised, ablating the surrounding tooth structure. Preparation is accomplished by a series of pulsed energy emissions resulting in multiple small dot-shaped areas of tooth removed on the surface of the tooth (Figure 10).
The effect is very superficial with less vibration and heat (Stabholz et al, 2003). A primary advantage of tooth preparation with erbium YAG is often preparation can be achieved with little or no anaesthesia.
It is important to start with very low energy for the first minute to condition the pulp so that there is no discomfort during preparation. The lowest energy to accomplish the preparation is best and is controlled by the pulsing frequency and the power setting.
The laser handpiece does not touch the tooth during preparation. The optimal distance from the tooth is best determined by listening for the pulses to be the loudest. The handpiece is constantly moved and the resulting tooth shaping is observed (Figure 11).
Preparation parallel to the tooth surface is best. Though actual preparation time may be longer than with a traditional high-speed handpiece, the time saved by not waiting for anaesthesia often allows small restorations to be placed at recare appointments rather than having to reappoint. Lasers are suitable for use in most direct restorative preparations but are best suited in class I, III, and V restorations.
Clinical use of hard tissue laser on pitted incisors with a two-layered composite technique
Several companies produce composites designed to be used in a dual-layering technique. Some use a high chroma dark dentine and translucent enamel; others use a more opaque general purpose layer, which is layered with a translucent enamel. One material that uses the later approach is Mosaic (Figure 12).
A 27-year-old male presented to our office with pitted and stained incisors (Figure 13). He was getting married in a few months and was concerned about the appearance of his smile in the wedding photographs.
Composite from a new two-component general purpose and enamel system was tried in and layered to determine the appropriate shades to be used (Figure 14). The laser was used to prepare the affected areas of the facial surfaces of both central incisors and the left lateral incisor (Figure 15).
The left incisors were restored using two layers. The surface was shaped using a very fine flame shaped diamond (Neodiamond 3512.10, Microcopy), a finishing carbide (Neocarbide ET9, Microcopy), a finisher (Enhance, Caulk Dentsply) and two polishers (Diacomp Feather Lite medium and fine composite polishers, Brasseler).
The right central incisor was built up first using the general-purpose shade A3 composite (Figure 16) and then the enamel shade ET composite (Figure 17). The restoration was shaped, finished, and polished in a similar manner (Figure 18).
Clinical use of hard tissue laser on class V abfraction lesions with a three-layered multiple products composite technique
Sometimes different composites from different manufacturers can be layered to best achieve a more natural appearance. A 52-year-old male presented to our office with severe abfraction lesions (Figure 19). Several composite materials were tried in and three layers of different brand composites were selected (Figure 20).
The molar was first prepared using the laser and restored. Then the two premolars were prepared using the laser (Figure 21). The first layer of dentine material was used (Figure 22). Then a layer of regular all-purpose shade A3 composite was used (Figure 23). Finally, a spherical composite shade A2 was used for the enamel layer (Figure 24). The composites were shaped, finished and polished (Figure 25).
Summary
Teeth are comprised of different components. In order to match the original appearance, restorative materials should be used that exhibit similar optical qualities as natural teeth. Selecting composite materials for each individual situation, based on physical properties as well as their opacity/translucency, gives the best results.
The hard tissue laser can be very useful and comfortable for the patient. Often not having to anaesthetise is a big advantage allowing more efficient use of time. Incorporating new technology and materials into the practice can enhance productivity, increase self-satisfaction and better please our patients.
This article was originally published in Oral Health, April 2017.
Dr Dan Ward earned his DDS degree from the Ohio State University in 1979 and has practiced in Columbus since graduation. He is a fellow of the Academy of General Dentistry, the American Society for Dental Aesthetics, the American College of Dentists, and the Pierre Fauchard Academy, a diplomat of the American Board of Aesthetic Dentistry, and a member of the American Academy of Cosmetic Dentistry, the American Dental Association, the Ohio Dental Association and the Columbus Dental Society.
References
Baratieri LN, Araujo E, Monteiro S Jr (2007) Color in natural teeth and direct resin composite restorations: essential aspects. Eur J Esthet Dent 2(2): 172-86
Blank JT (2003) Simplified techniques for the placement of stratified polychromatic anterior and posterior direct composite restorations. Compend Contin Educ Dent 24(Suppl 2): 19-25
Dietschi D, Ardu S, Krejci I (2006) A new shading concept based on natural tooth color applied to direct composite restorations. Quintessence Int 37(2): 91-102
Nazemisalman B, Farsadeghi M, Sokhansanj M (2015) Types of lasers and their applications in pediatric dentistry: a review. J Lasers Med Sci 6(3): 96-101
Stabholz A, Zeltser R, Sela M, Peretz B, Moshonov J, Ziskind D, Stabholz A (2003) The use of lasers in dentistry: principles of operation and clinical applications. Compend Contin Educ Dent 24(12): 935-48
Terry DA (2003) Dimensions of color: creating high-diffusion layers with composite resin. Compend Contin Educ Dent 24(Suppl 2): 3-13
Villarroel M, Fahl N, De Sousa AM, De Oliveira OB Jr (2011) Direct esthetic restorations based on translucency and opacity of composite resins. J Esthet Restor Dent 23(2): 73-87
Ward DH (2001) Proportional smile design using the recurring esthetic dental (RED) proportion. Dent Clin North Am 45(1): 143-154
Ward DH (2015) Smile Design by the Numbers. Oral Health 105(4):80-86
