Dr. Robert A. Lowe

flowable composite resins for several years. These were traditionally designed as a dentin replacement only, requiring an enamel layer to withstand occlusal function and wear because of limitations in the physical properties of the material. Dentists largely agree that flowable resins, in general, increase the potential for precise marginal adaptation, with a lower viscosity compared with conventional paste composites. Therefore, the line angles and point angles of cavity preparations lined or filled with a flowable composite restorative material may have a reduction in the potential for marginal failure from microleakage.

Bulk fill technologies have been developed to decrease the need to layer with traditional materials, whose clinical performance can diminish because of polymerization shrinkage and/or depth of cure issues.

 Because most dentists have had on their wish list a composite material that behaves like amalgam, a single, bulk fill material would be beneficial and welcome. Thanks to a unique filler technology now used in a flowable composite material, a bulk fill flowable restorative material has the physical strength to make capping with traditional composites a thing of the past.

The Importance of Fillers in Composite Resins

The size and shape of fillers in composite materials have a direct bearing on the physical properties of the material. The higher the filler load, the closer the fillers can be packed together, minimizing the amount of resin between each particle and leading to higher strength, better optical properties, and better polishability.

Uniformly sized spherical fillers with an average diameter of 200 nm produce a composite material that, not only has excellent physical properties and wear resistance, but is also highly polishable. The wear on the material from the opposing dentition is virtually zero. Because of the uniform shape of the spherical fillers, they can rotate and move during photopolymerization. The result is less potential polymerization shrinkage and less microleakage between the restoration interface and the tooth.

An Evolution in Bulk Fill Flowable Composite Resins

With the introduction of Estelite Bulk Fill Flow from Tokuyama Dental America, a new class of bulk fill flowable composites arrived in 2019 and a revolutionary change occurred in how clinicians use bulk fill flowables. They eliminated the need for a traditional nanohybrid capping layer as the final increment of the restoration. According to the manufacturer, the spherical nature of the fillers in the material allows for an increase in physical properties and esthetics (particularly opacity), the main reason traditional flowable composites have been indicated for dentin replacement only. For Estelite Bulk Fill Flow, the supranano spherical fillers are made of silica-zirconia produced by the sol-gel method at a mean particle size of 200 nm.

Utilizes spherical filler technology for superior final results

Lower wear and abrasion for restorations that last

Higher cavity adaptation prevents gaps and voids

Because of their uniform geometry, these supranano-sized filler particles can be closely compacted in the resin matrix to increase the quality of the physical properties (wear resistance, compressive, and tensile strength) of the material. Also, they allow for a higher diffusion and refraction of light that penetrates into the material itself. This allows for a more predictable depth of cure and increases the material’s ability to blend esthetically with the adjacent tooth structure.

Estelite Bulk Fill Flow is also unique because it is more translucent at placement, to allow for depth of cure of up to 4 mm. Then, during photopolymerization, the material becomes more opaque to better match the optical properties of the surrounding tooth structure (enamel). When photopolymerization is finished, clinicians can quickly achieve a high degree of polish, as the spherical fillers, with an average size of 200 nm (supranano), create a smooth surface and will maintain high luster. Abrasion and “plucking” will not affect the quality of the reflectivity and shine for years.

A Class III Anterior Restoration Using a Bulk Fill Flowable Composite

A class III distal composite shown in tooth number 7 

 has evidence of marginal leakage and is in need of replacement.

The composite material and any existing recurrent decay are removed using a 330-carbide bur from SS White Dental while protecting the adjacent surface with a WedgeGuard 

. An anatomically contoured mylar Bioclear Matrix from Bioclear is placed, and the gingival margin of the preparation is sealed using an interproximal wedge such as those from Bioclear or the DualForce Wedge from Clinician’s Choice.

The preparation is selectively etched on the enamel periphery using 37% phosphoric acid for 15 seconds and then rinsed with water. The enamel is dried with air, and then the bonding agent, Tokuyama Universal Bond from Tokuyama Dental America, is placed on both enamel and dentin with a microbrush.

The selected shade (A2) of Estelite Bulk Fill Flow is then placed into the cavity preparation 

. A sable brush is used to gently remove any minimal excess and ensure the cavity margins are covered.

It is crucial to emphasize the importance of a properly fitted anatomic matrix to limit any potential excess material as it is placed into the preparation. The goal should be as little rotary finishing and contouring as possible.

After light curing the composite per the manufacturer’s instructions, the matrix system and isolation are removed, and the finishing process can begin. Proximal contacts are easily adjusted 

 using different grits of the ContacEZ Restorative Strip System from ContacEZ. This strip system combines efficient precision contouring of all proximal surfaces of composite restorations (anterior and posterior) with the ability to maintain the proper anatomic contour (convex), which can be difficult to impossible to achieve with traditional diamond abrasive strips because of access limitations. In addition, the serrated edge helps gain access to the interproximal of a recently finished composite restoration should bonding resin be inadvertently polymerized during placement, blocking the occlusal embrasure and access to the interproximal area for the instrument and to dental floss.

Lastly, final polishing of the restoration is achieved using rubber composite polishing instruments such as A.S.A.P. All Surface Access Polishers fromClinician’s Choice (

 shows a post-operative view of the completed restoration from the occlusal aspect. Note the extremely high luster achieved and how nicely the restorative material blends into the surrounding tooth structure. 

 shows a 2-year follow-up on the placement of the restoration.

A Class II Posterior Restoration Using a Bulk Fill Flowable Composite

A class II DO composite shown in tooth number 12 

 has a fractured marginal ridge and is in need of replacement.

The remaining composite material and any existing recurrent decay is removed using a 330-carbide burwhile protecting the adjacent surface with a WedgeGuard (

Once removal of the existing restoration is complete, the quadrant is isolated with an Isolite from Zyris and DryTips from Microbrush International to cover the Stensen (Parotid) duct. Next, a DualForce sectional matrix from Clinician’s Choice is placed around the completed cavity preparation (

The preparation is selectively etched onto the enamel periphery using 37% phosphoric acid for 15 seconds and then rinsed with water. The enamel is dried with air, and then Tokuyama Universal Bond is placed on both enamel and dentin with a microbrush 

. A sable brush is used to gently remove any minimal excess and ensure the cavity margins are covered. Because a capping layer is not required with Estelite Bulk Fill Flow composite, the cavity preparation is completely filled to the cavosurface margin and the top of the matrix band in the interproximal area.

Again, I emphasize the importance of a properly fitted anatomic sectional matrix to limit any potential excess material as it is placed into the preparation. The goal should be as little rotary finishing and contouring as possible. After light curing the composite per the manufacturer’s instructions, the matrix system and isolation are removed, and finishing can begin.

The occlusal contacts are checked with articulating paper 

 and adjusted as needed using a needle or a mosquito-type composite diamond finishing bur such as the #8392.016; from Komet USA (

Next, the restoration is polished using A.S.A.P. All Surface Access Polishers from Clinician’s Choice (

). The Restorative Strip System from ContacEZ is used to remove any excess resin bonding material and refine the interproximal contours as needed to make sure dental floss can slide cleanly through the contact area 

 shows a post-operative occlusal view of the completed restoration. Note the extremely high luster achieved and how the restorative material blends into the surrounding tooth structure. 

 shows a 2-year follow-up on the placed restoration.

For many years, clinicians have longed for composite restorative materials with a more simplified, less technique-laden approach to clinical placement. A bulk fill flowable composite offers the benefit of accurate adaptation to the cavity preparation while eliminating the need for incremental placement and condensation (plugging).

Estelite Bulk Fill Flow goes one step further by eliminating the need for an enamel capping layer so cavity preparations of 4 mm or less can be filled entirely with one increment of bulk fill flowable composite. Given the high polishability from the presence of spherical fillers, as well, Estelite Bulk Fill Flow offers the clinician a high-quality restorative option for a variety of clinical applications and is showing excellent long-term clinical results.

Ilie N, Bucuta S, Draenert M. Bulk-fill resin-based composites: an in vitro assessment of their mechanical performance. 

. 2013;38(6):618-625. doi:10.2341/12-395-L

Campodonico CE, Tantbirojn D, Olin PS, Versluis A. Cuspal deflection and depth of cure in resin-based composite restorations filled by using bulk, incremental and transtooth-illumination techniques. 

. 2011;142(10):1176‐1182. doi:10.14219/jada.archive.2011.0087

Rees JS, Jagger DC, Williams DR, Brown G, Duguid W. A reappraisal of the incremental packing technique for light cured composite resins. 

. 2004;31(1):81‐84. doi:10.1046/j.0305-182x.2003.01073.x

Flury S, Hayoz S, Peutzfeldt A, Hüsler J, Lussi A. Depth of cure of resin composites: is the ISO 4049 method suitable for bulk fill materials? 

. 2012;28(5):521‐528. doi:10.1016/j.dental.2012.02.002

El-Safty S, Silikas N, Akhtar R, Watts DC. Nanoindentation creep versus bulk compressive creep of dental resin-composites. 

. 2012;28(11):1171‐1182. doi:10.1016/j.dental.2012.08.012

Roggendorf MJ, Krämer N, Appelt A, Naumann M, Frankenberger R. Marginal quality of flowable 4-mm base vs. conventionally layered resin composite. 

. 2011;39(10):643‐647. doi:10.1016/j.jdent.2011.07.004

Mousavinasab SM. In: John Cuppoletti J, ed. 

Effects of Filler Content on Mechanical and Optical Properties of Dental Composite Resin, Metal, Ceramic and Polymeric Composites for Various Uses.

http://www.intechopen.com/books/metal-ceramic-and-polymeric-composites-for-various-uses/effects-of-filler-content-on-mechanical-and-optical-properties-of-dental-composite-resin

Rüttermann S, Wandrey C, Raab W H-M, Janda R. Novel nano-particles as fillers for an experimental resin-based restorative material. 

. 2008;4(6):1846‐1853. doi:10.1016/j.actbio.2008.06.006

Lee JH, Um CM, Lee IB. Rheological properties of resin composites according to variations in monomer and filler composition. 

. 2006;22(6):515‐526. doi:10.1016/j.dental.2005.05.008

Yuasa S. Composite oxide spherical particle filler. 

Articles

With the introduction of Estelite Bulk Fill Flow, a revolutionary change occurred in the way clinicians use bulk fill flowable composites.

How to Bulk Fill Flowable Composite Restorations Without a Capping Layer

	Functional and esthetic requirements in conjunction with material strength dictate the amount of tooth reduction required for a specific case.

	Recently, dentistry has seen a shift from gold-based metallic restorations to milled materials (e.g., 

 [Ivoclar Vivadent] and zirconia) due to lower production costs. Because both lithium disilicate and zirconia can be 

conventionally cemented or bonded to tooth structure (zirconia requiring a metallic primer for maximum bond strength), the reduction requirements may vary depending on the choice of cement.

	For conventional cementation, high-strength ceramics generally require the same amount of tooth reduction as traditional porcelain-fused-to-metal crowns. Generally, 1.5 to 2.0 mm of space is recommended for occlusal and incisal clearance so these crown materials can perform well in high-stress functional areas without the risk of fracture. Furthermore, rapid, efficient tooth reduction minimizes biologic trauma to the tooth and dental pulp during the preparation process. 

 (Komet USA LLC) have been specifically designed for ultra-fast, effective removal of tooth structure, offering measurably greater tooth reduction without sacrificing operator control (Figs. 1-3). This is achieved by using a new diamond-grit size of 230 micrometers (versus the average 181-micrometer particle size of standard super-coarse diamonds), uniformly sized at an optimal depth to produce an efficient cut without instrument clogging.

	Following gross reduction with Deep Purple diamonds, a fine-grit finishing diamond instrument is recommended for finishing and smoothing the preparation for a more intimate fit of the restorative material. Note: Identically matched Komet

 8856 finishers correspond in size and configuration with Deep Purple diamonds. 

Read more: Komet USA launches Deep Purple™ diamonds for efficient crown prep

	Up next: Crown preparations for high-strength ceramics

	 Crown preparations for high-strength ceramics 

	Uniformity of tooth reduction is important to the successful fabrication of indirect dental restorations. With the various types of materials available, it is important to understand preparation requirements so the proper amount of tooth structure is removed 

according to the functional and esthetic requirements of the restorative material. The following technique outlines the proper steps for tooth preparation prior to indirect restoration with a high-strength ceramic.

	Create vertical depth cuts into the middle and incisal one-thirds of the tooth, following the angle of the facial plane in the incisal one-third. The diameter of the instrument (856XC.FG.016) at the tip is 1.6 mm; therefore, the diamond should produce a depth cut to approximately one-half its total diameter (approximately 0.8 mm) (Fig. 4). Note: As a safety option, Komet USA’s 

 enable the user to reliably achieve and maintain the minimum layer thickness for all-ceramic restoration preparations.

Click here to see the depth-marking diamonds in action!

	To “erase” the depth cuts, “paint” with the bur in a horizontal plane (Fig. 5).

	Place depth cuts in the cervical plane to approximately one-half the depth of the end of the bur. This leaves a rounded shoulder finish line with a 90-degree cavosurface angle (Fig. 6).

	Up next: More tips on how to achieve great results with diamond instruments

	The two-plane labial reduction is shown from the facial aspect. A three-quarter view shows the refinement of the two-plane reduction, with the bur positioned parallel to the cervical one-third plane of reduction (Figs. 7-8).

	Use the 856XC.FG.016 tapered-cylinder diamond to place 1.0-mm depth grooves on the incisal edge (Fig. 9 ), and reduce the incisal edge to form an acute angle to the facial surface (Fig. 10).

	Cut a depth groove by applying the 856XC.FG.016 rounded-cylinder diamond on the lingual surface, taking care to follow the natural contour of the tooth. The cervical plane formed by preparation of the cingulum should diverge 10 to 15 degrees from the cervical plane on the labial surface (Fig. 11).

	With a football-shaped diamond (5379.FG.023), eliminate the depth groove in the lingual concavity only (middle and incisal one-thirds of the lingual surface) (Fig. 12).

	Reduce the cervical third of the lingual surface and blend the finish line to both proximal aspects with the 856XC.FG.016. Note: Remember to keep the depth uniform in the axial direction (Fig. 13).

	Verify the lingual reduction by asking the patient to close in centric occlusion: Observe the uniformity of lingual reduction as the patient moves forward in protrusive with light incisal contact (Fig. 14).

	Use a 46-micron, round, tapered-cylinder finishing diamond (8856.FG.016) to refine and smooth the axial walls on all aspects of the preparation, followed by the incisal edge (Fig. 15).

	Apply a 46-micron football-shaped finishing diamond (8379.FG.023) to finish the lingual concavity of the preparation (Fig. 16). 

	Figure 18 shows a labial view of the completed all-ceramic crown preparation. Note the uniform thickness of the finish line circumferentially as well as the overall smoothness of the transitional line angles. The preparation should be as smooth as possible to increase accuracy of fit and ease of delivery. The final result is a combination of structural strength and esthetic beauty-the “ideal” dental restoration in every sense of the word.

A technique showcasing the Deep Purple™ diamond instruments from Komet USA LLC. and how they can simplify process the of tooth reduction.

How to perform rapid tooth reduction with diamond instruments

There are many situations in fixed prosthetics where long-term provisional restorations are a necessary part of the treatment plan. 

Conventional provisional materials cannot always be used for this purpose. In this article, some clinical situations will be discussed where a new process called 

“Snap-On Smile” can be used successfully as a long-term provisional restoration

 that can successfully transition patients to their definitive restorations comfortably and predictably.

For patients getting implant restorations, the four to six months they wait for osseointegration to occur, and then the time after to complete the restorative process, can be challenging from a functional and esthetic point of view. 

Most of the time, the patient wears a “flipper partial” that does not fit very well, and like an orthodontic retainer, partially covers the palate. 

Patients usually cannot eat with the flipper partials in place, and rarely are they an esthetic match for the adjacent teeth

.  With DenMat’s Snap-On Smile, these objections are overcome and patients can have an esthetic appliance they can wear while eating.   

 was having implants placed for tooth Nos. 11 and 12, the last step of full mouth rehabilitation. 

The canine–premolar area is a difficult position to deal with for interim esthetics and function. When the patient was in provisional restorations for the rehabilitation, the tooth No. 11-12 area was provisionalized with a bis-acrylic splinted bridge. At the final ceramic try-in, an impression was taken with the definitive restorations in place so a Snap-On Smile quadrant provisional restoration could be fabricated and placed at final delivery. 

The impression needs to be a detailed crown and bridge impression using light bodied injectable and heavy tray materials. 

The individual units are placed on the preparations with a drop of temporary cement in the occlusal or incisal areas for stability during the impression process. The Snap-On Smile implant provisional for this case extended from tooth Nos. 10 to 14 (

With this provisional, the patient may function with it in place, yet remove it when necessary (

). The material’s resilience allows for a “snap fit” around the heights of contour of the teeth without fracture or breakage. 

Snap-On Smile gives patients the confidence they deserve while waiting for their implant restorations to be completed. 

Snap-On Smile is both strong and stain-resistant and will retain its original appearance for years.

 had implants restored for missing teeth in the maxillary anterior area. His treatment plan included a mandible anterior bridge to restore congenitally missing central incisors. But because of budgetary constraints and an impeding wedding, the patient did not plan to have the mandibular restoration completed right away, and wasn’t sure when he’d be able to.

Without preparing the abutment teeth, the only provisional option would again be a “flipper partial,” which is even more difficult to wear on the lower arch. For that reason, Snap-On Smile was the obvious choice for an interim functional and esthetic appliance (

Snap-On Smile offers an excellent option over “flipper partials” for cases requiring long-term provisional restorations, whatever the reason. The esthetics, strength and stability this appliance offers make it the obvious choice for clinical situations that require a long-term interim appliance that patients can really live with.

There are many situations in fixed prosthetics where long-term provisional restorations are a necessary part of the treatment plan.  Conventional provisional materials cannot always be used for this purpose. In this article, some clinical situations will be discussed where a new process called “Snap-On Smile” can be used successfully as a long-term provisional restoration that can successfully transition patients to their definitive restorations comfortably and predictably.

How to create esthetic, durable long-term provisionals with DenMat's Snap-On Smile [VIDEO]

"Fractured ceramic crowns are an everyday problem in dental practice. It is not always feasible or cost effective to replace the ceramic restoration for the patient if a repair can be made using composite resin. In this article, a new self adhering flowable composite, Vertise Flow, will be used to demonstrate a simplified approach to porcelain repair that does not require the use of Hydrofluoric acid or silane priming."
	-

	The need to repair broken ceramic restorations is a common occurrence in the dental practice. It is not always cost effective, for the patient or the dentist, to replace the ceramic restoration if the restoration can be predictably repaired with composite resin. If the fracture is minimal, and there is available porcelain and /or tooth to bond to, the repair often can be done using composite resin.

	There are many steps involved in preparing the fractured surface before composite placement. Using hydrofluoric acid (HF) to sufficiently etch ceramic traditionally has been required to prepare the ceramic surface to adequately adhere to dentin adhesives that are typically used to place composite. HF is very caustic to the tissues and must be used with extreme caution. The challenge is to limit the HF to the ceramic and make sure it doesn’t come in contact with the gingival tissues or tooth substrate. After etching the ceramic, silane couplers traditionally are applied to increase the adhesive’s bond strength to the ceramic. The fractured area is ready to accept the composite resin repair only after careful preparation of the ceramic and tooth surface.
	
	Kerr Corp.’s Vertise Flow, a revolutionary new material, is one of the latest advances in composite resin technology available to dentists. This “self adhering” composite resin is designed to combine the etch, rinse, bond and flowable liner steps in placing composite resin restorations into one easy step. During the development of this technology, Bui, Nguyen, Qian, and Tobia1 tested the efficacy of using Vertise Flow to bond composite to ceramic with and without conventional surface preparation using HF and silane coupling agents. Their study concluded it offered effective bonding to porcelain substrate without HF or silane, simplifying the clinical process of ceramic repair for the dentist.  
	
	The following are two clinical cases that demonstrate the technique.
	
	

Clinical case No. 1: A Class IV incisal fracture of a ceramic veneer

is a pre-operative view of a Class IV distal ceramic fracture of a porcelain veneer on tooth No. 24. This type of fracture can occur during lateral excursions and can be in part due to a “cross over” lateral interference, a sharp distal-incisal preparation angle, or a traumatic accident. As seen from the incisal view, this fracture is entirely in ceramic (

). The fractured edge is prepared using a course diamond to create a 2 to 3 mm bevel from incisal edge to proximal surface (

	If available, air abrasion can be used to enhance micromechanical adhesion to the ceramic. A course diamond also works. A dead soft matrix strip is used on the proximal side opposite the fracture to isolate the operative area. On the side of the repair, Tapetrix Matrix Tape (Novadent) is used to isolate. Because you can stretch this tape very thin and create a small, elliptical window for composite contact, this works well when restoring proximal contacts in anterior Class 3 and Class IV situations. 

) and then brushed onto the prepared ceramic surface making sure to agitate and saturate the beveled area of porcelain (

). After light curing for 20 seconds, Kerr’s Herculite Ultra is used in shade matching the existing porcelain and to rebuild the tooth’s missing disto-incisal corner. Herculite Ultra, designed for a mono-layering technique, eliminates the need for a complex build up for such a small restoration and creates a beautiful chameleon effect with the surrounding porcelain. The nano hybrid composite is applied and sculpted with a composite plastic filling instrument such as Hu-Friedy’s Goldstein Flexithin Mini 4 (

	Once the composite is placed and light cured for 20 seconds, the contouring and finishing process can begin. Flexible composite finishing discs (OptiDisc from Kerr Hawe) are used, first in medium then fine grits to contour the composite repair and refine the marginal interface. It is very important to use water spray and make sure the OptiDisc is rotating from the composite material toward the ceramic surface to create an “invisible” transition from restorative material to ceramic (

).  Next, 30 micron diamond interproximal finishing strips (Axis Dental) are used to contour and refine the restoration’s proximal marginal contour (

). Be careful to use this strip apical to the contact area only. Aluminum Oxide polishing strips (GC America’s Epi-tex) will further polish the restoration’s proximal surface and not remove the contact area (

). Polish the composite’s surface with rubber abrasive discs, again making sure the disc rotation is toward the ceramic surface (

).
	
	The final polishing step is completed with an Occlubrush cup, from KerrHawe, without water spray. The occlubrush will impart a beautiful luster to the composite resin (

). A surface sealant (Kerr’s Optiguard) is applied, air thinned and light cured for 20 seconds (

). The purpose of the surface sealant is to microscopically seal the interface between the composite and the porcelain and to help guard against staining. 

 shows the completed ceramic repair using Vertise Flow and composite resin. Comparing this with the pre-operative view in 

, it is difficult to see a composite repair has been performed.

 had a porcelain fracture in the cervical region of a porcelain veneer on tooth No. 10. Because it is difficult to match a single veneer from a laboratory standpoint, one option is to repair the affected area with a composite resin. The surface of the tooth structure and about a 2 mm area of porcelain incisal to the fracture line is treated with an air abrasion device with 50 micron particles of aluminum oxide powder (

). This creates a micromechanically roughened surface to increase the quality of the composite resin’s bond to the tooth.

), it is common to have a little hemorrhage secondary to gingival abrasion (

). Kerr’s Hemostasyl is an astringent material used to eliminate the gingival hemorrhage and create a suitable environment for dental adhesive chemistry (

). Its “mousse-like” viscosity allows the operator to confine the material to a localized area and keeps the astringent from dissipating from the area until it is rinsed away (

).  
	
	
	Next, Vertise Flow is dispensed onto the cervical area (

) and dispersed over the tooth surface and porcelain that has been microetched using the brush (

) that is included with the Vertise kit. Using this type of brush versus traditional microbrushes increases the material’s bond strength. This facilitates a more aggressive, intimate contact of the material to the tooth substrate, which allows a better interaction of the chemistry with the calcium ions in the dentin and phosphate groups in the adhesive monomers of the bonding system.
	
	After light curing (

) the appropriate shade of composite (Kerr’s Herculite Ultra) is placed over the cured Vertise in the cervical area to be restored (

). After sculpting with a plastic filling instrument, a sable artist’s brush is used to blend the composite material (

) and refine the margin interface between the composite and ceramic. After light curing, the composite material is contoured using carbide composite finishing burs from Axis Dental (

). Polishing is accomplished with rubber abrasive discs (

) and completed with an Occlubrush, both from KerrHawe (

). After an application of Optiguard surface sealant (

), the completed porcelain repair is shown in 

	A technique for porcelain repair has been described that by using the characteristics of Vertise Self Adhering Composite to simplifiy the process, eliminating several steps, while producing an esthetically excellent clinical result.

Robert A. Lowe, DDS, FAGD, FICD, FADI, FACD, maintains a private practice in Charlotte, N.C. Dr. Lowe lectures internationally and teaches CE and dental training courses around the world on esthetic and restorative dentistry topics. He has worked with leading dental manufacturers as a clinical evaluator of new materials and products and has been published in several well-known dental journals. He can be reached at 

 THE SET-UP  "Fractured ceramic crowns are an everyday problem in dental practice. It is not always feasible or cost effective to replace the ceramic restoration for the patient if a repair can be made using composite resin. In this article, a new self adhering flowable composite, Vertise Flow, will be used to demonstrate a simplified approach to porcelain repair that does not require the use of Hydrofluoric acid or silane priming." -Dr. Robert A. Lowe, team lead

Go with the flow

	There is no material in the history of dentistry that has undergone as much evolution as composite resin. The face of restorative dentistry changed forever when successful bonding to dentin was achieved. Since then, the goal of clinical and material science has been to find simple, predictable approaches to the composite restorative process.

	Unlike dental amalgam, the patrician of direct restoratives, placing composite requires many more steps and exacting technique to achieve the best results. The process of adhesion, conditioning the tooth surface, applying primers and adhesives, followed by layering the composite resins to complete the restorative process involves many independent steps that must be properly executed to ensure good results. Successive generations of dentin adhesives have sought to decrease the number of steps for placement without sacrificing clinical results. The seventh-generation self-etching dentin bonding systems have helped decrease technique and post-operative sensitivity issues while still yielding clinically acceptable restorations. Many clinicians even have used flowable resins as the first layer of composite resin after placing adhesive to ensure precise wetting of the adhesive surface, while creating a layer with less polymerization stress because of a lower modulus of elasticity (< 0.5 mm thickness).

	A new composite material, Kerr Corp.’s Vertise Flow (

), combines the adhesive and flowable steps into one, resulting in one of the first self adhering composite materials on the market.

	There are two distinct mechanisms of adhesion for self adhering materials-chemical and micro-mechanical. The primary bonding mechanism for Vertise Flow is chemical bonding between the calcium ions in the hydroxyapatite crystals and the phosphate groups in the glycerol diphosphate dimethacrylate (GPDM), which is the adhesive monomer common to all adhesives in Kerr’s OptiBond family of dentin adhesives.

	Vertise Flow also bonds to tooth structure via micro-mechanical retention, which is the result of the interpenetrating network formed between the polymerized monomers in the material and the collagen fibers and hydroxyapatite crystals within the smear layer. Brushing this first layer of material vigorously into the tooth surface enhances this penetration into the smear layer and creates a bond comparable to what most available seventh-generation dentin bonding agents can achieve.

	Two clinical cases will be presented to illustrate a “simplified approach” to matrix and placement of direct posterior composites. This technique provides an accurate reproduction of the proximal surface and contact, also decreasing the number of steps involved in the adhesive restoration process. Decreasing the amount of rotary finishing and contouring required to complete the restorative process also saves chair time.

	The patient presented with a Class II cavity present on the mesial surface of a maxillary left second molar (

). After preparation of the proximal box portion of the preparation, the interproximal gingival papillae was “nicked” with the bur, causing hemorrhage that could interfere with the bonding process. A new hemostatic product, Kerr’s Hemostasyl, is syringed into the proximal area. It remains in place for about one minute (

) and is then rinsed away with an air-water spray. Hemostasyl’s consistency keeps it in place until it is removed, unlike liquid-type hemostatic agents. 

 shows two approximating preparations in the maxillary left first and second premolars.

	After placing and rinsing Hemostasyl, the proximal area between the premolar preparations is devoid of blood, and placement of the matrix can be done easily without causing the tissue to bleed 

	A sectional matrix, Garrison Dental Solution’s Composi-Tight 3D
	(

) is used to simplify the restorative process. The “soft anatomically shaped pads” of the 3D ring fill the proximal embrasure spaces, adapting the sectional matrix strip precisely to the cavosurface margins. The contact is assured without burnishing the band against the adjacent tooth, causing deformation of the restoration. As long as the band is visually touching the adjacent surface, because the ring causes separation by compressing the periodontal ligament spaces, a curved hemostat will be required to remove the band when the restoration is complete.

	The latest improvement to the Composi-Tight 3D system is “Slick Bands.” The non-stick inner surfaces allow for more accurate and smooth proximal surfaces when placing the composite material.

	Once the sectional matrix is placed, the restorative process begins. Vertise Flow self adhering flowable composite replaces the need for the conventional bonding steps of etching, rinsing, and adhesive placement prior to the application of the flowable resin. A thin layer of Vertise Flow (less than 0.5 mm in thickness) is brushed onto all cavity walls, enamel and dentin, (bevels included) with moderate pressure for 15 to 20 seconds. Any excess around the margins is removed with the brush 

 and the material is then light cured for 15 to 20 seconds. 

 shows the preparation after application of Vertise Flow to all cavity surfaces and light curing. Notice the appearance of the cavity surface compared with the freshly prepared surfaces in 

. The surfaces of the cavity appear similar to a “faux painted,” textured surface. This is indicative of the correct amount of Vertise Flow used for the initial creation of the adhesive layer to dentin and enamel. If desired, an additional increment of Vertise Flow can then be applied (up to 0.5 mm) as a cavity liner and spread with a brush into all line and point angles of the preparation (

. This ensures complete and accurate covering of all internal cavity walls.

	As direct composites have evolved for universal application, there always has been a trade off in handling and polishablity for materials designed for anterior and posterior use. A new nanohybrid, Kerr’s Herculite Ultra, simplifies esthetic anterior and posterior placement of composite resins, according to the manufacturer. This product has been positioned for use in a mono-layering technique as an alternative to complicated layering to achieve optimal esthetic results. The consistency of Herculite Ultra is creamy, yet it is a sculptable material with no slumping and good chameleon effect.

	The first increment of Herculite Ultra is placed and condensed using a non-serrated plugger 

. A plastic filling instrument is used to sculpt the occlusal layer of the maxillary left second premolar 

. Note that in this case, where adjacent proximal surfaces require restoration, apply the matrix and restore one preparation to completion, then matrix the other tooth and restore it creating contact to the first restoration. Always contour and polish the finished composite surface as needed before filling the adjacent preparation.

), a small 8-fluted carbide finishing bur, is used to finesse the occlusal embrasure occlusal to the proposed contact area 

. Remember, the proximal contact is located 1 mm apical to the height of the marginal ridge. Once polished, the sectional matrix is applied to the adjacent tooth, and the restoration is completed 

 show the completed restorations after application of surface sealant. Note how nicely the restorations blend into the natural tooth.

	A technique has been shown using an innovative self adhering composite and a simplified mono-layering nanohybrid composite system. Vertise Flow has been shown to deliver comparable results to many of the seventh-generation bonding systems without the need for a separate bonding step. Combined with a simplified restorative system, such as Herculite Ultra, a more concise, less technique sensitive alternative to traditional direct composite placement is now available.

 There is no material in the history of dentistry that has undergone as much evolution as composite resin. The face of restorative dentistry changed forever when successful bonding to dentin was achieved. Since then, the goal of clinical and material science has been to find simple, predictable approaches to the composite restorative process.