Finishing Orthodontics for Undersized Teeth: The Bioclear Method

by David Clark, DDS

Orthodontics has seen significant advances over the past decade. In spite of these advances, there is no magic wand when teeth are undersized. In addition, there are a staggering number of adult ortho cases that produce the dreaded black triangle; an esthetic dilemma that is considered to be more unsightly than the crowding that led to the ortho in the first place. In this article we will discuss undersized teeth.

Bioclear Injection Over-Molding versus “Bonding”
“Bonding” sounds like a cheap way to fix a wrecked car fender. This has given composites a bad name (Fig. 1). “Cosmetic Dentistry Experts” online tell the public that bonding is inferior to porcelain veneers. Flawed systems, lack of training, and a dearth of proper composite engineering principles eventually cause teeth to look like poor asphalt patchwork. The Bioclear approach is not bonding. It is injection overmolding. Instead of just patching the tooth, the Bioclear Matrix and method allows the entire tooth to be overmolded with variable thickness composite. Properly done, the Bioclear matrix and method is superior to porcelain for young post-ortho patients to complete injection overmold cases with undersized incisors.

FIGURE 1. This patchwork style bonding on the central incisors gives composite a bad name. Note the excess translucency, small holes full of brown stain, and most importantly an ignorance of the larger issues that could have been addressed if the teeth had received the modern approach outlined in this article.

Double Trouble! Figure 2 shows identical Twins with peg laterals. At first glance with a straight facial view, the twins might just look like they need a “little bonding” on the peg laterals (Figs. 3 & 4). However, a closer profile angled look (Figs. 5 & 6) reveals that all of the four incisors were undersized. Simply adding to the lateral incisors, or even just to the four anterior teeth, would produce inappropriately sized teeth. With the Bioclear method, “bonding to hide gaps” has evolved to “360° composite overmolding” for a strong, predictable and permanent solution.

FIGURE 2. Identical twins with undersized teeth and peg laterals. When compared with the post-operative photographs, these faces seem a little sad and straining to smile. Most patients hate tooth gapping far worse than dark teeth or crowded teeth.

FIGURE 3. Post-orthodontic, pre-restorative smile photograph of one of the twins.

FIGURE 4. Retracted post orthodontic, preoperative view of the maxillary anterior sextant.

FIGURES 5.  &  6. Lateral views of the peg laterals and general spacing dilemma. This view demonstrates that a comprehensive approach adding to all six anterior teeth using both anterior and diastema closure matrices would be needed.

FIGURE 5.

FIGURE 6.

After a discussion with the treating specialist, the ideal treatment of over-molding teeth 13, 12, 11, 21, 22, and 23 was agreed upon with the two patients, parents, and orthodontist.

The Treating Orthodontist’s View
“A tooth size discrepancy caused by narrow maxillary lateral incisors is a very common problem faced by orthodontists. Changing the tip and torque of the maxillary incisors or reducing the mesial distal dimensions of the lower incisors can often solve the discrepancy without the need for future maxillary restorations. However, when the discrepancy is large, as was the case with these twin sisters, restorations are a necessity. Determining the exact position to place the maxillary lateral incisors can be difficult, especially when working with various restoring dentists, each with different professional approaches. What impressed me the most about using the Bioclear Matrix method was the ability to modify the shape more apically on the mesial and distal aspects of the incisors, thereby changing the emergence profile and giving more flexibility for the position of the teeth. When discussing where to place the lateral incisors orthodontically, the treating restorative dentist was less concerned about their exact position than I was, and yet his results were excellent.” – Dr. Jerrold S. Johnson, Tacoma, WA, USA.

Rethinking Priorities in the Veneering of Teeth
Spend enough time at an esthetic academy and your head begins to spin when it comes to cases like this. Sadly, there is so much focus on diagnostic wax ups, proportionality rules, nuances of multiple shading of porcelain or composite, etc., that the average general dentist walks away thinking, “I can’t afford to spend that much time and energy on these cases”. In addition, too much effort is spent on pleasing the other dentists in the room and not enough on pleasing the patient, with little attention to the soft tissue response. Frankly, many of the “fancy porcelain cases” have mediocre soft tissue health and are simply inappropriate for a 14-year-old. Traditional direct bonding cases may look good for several months but then begin to stain. Horrific overhangs, residual black triangles, or a combination thereof, complicate the situation.

Many doctors using Bioclear have commented that the ideal and varied shapes of the Matrices (Fig. 7) have allowed them to throw away their diagnostic wax-ups and simply just get to work. This is a bottom line approach. The spaces must be closed. The matrix dictates the appropriate shape and emergence profile. The patient needs to love their smile. The restoration must be smooth, strong, and healthy, and the change in emergence profile must begin subgingivally, which requires the use of a diastema closure matrix (Fig. 8).

FIGURE 7. Matrix selection guide for the three most popular Bioclear diastema closure matrices.

FIGURE 8. The DC-203 matrix is shown along with the complete kit. Note the dramatic change in subgingival emergence profile that will stimulate true papilla regeneration. US patent #8,393,897. Green dotted line shows the typical notch that should be cut with the Bioclear micro-scissors to accommodate the papilla.

 

Trimming the Bioclear Matrices
When Bioclear matrices were first introduced, clinicians finally had a matrix with true multiple anatomic shapes. Through trial and error, we have discovered that for young patients or patients with “young bone”, the gingival apron needs to be trimmed with the Bioclear micro-scissors to duplicate the significant rise and fall of the attachment. These instructions are now carefully spelled out in the new user’s guide and online (Bioclearmatrix.com). This quick but crucial modification allows the matrix to seat up to 3mm deeper and fit more accurately. The matrix can be surprisingly comfortable as it slides gently and stably into the sulcus without bleeding. One of the reasons that a flat Mylar strip causes gingival bleeding is because it slices the delicate soft tissue. The soft tissue has the consistency of a ripe strawberry. It needs TLC.

Just Say No to Layering?
Layering is “fancy pants” dentistry that is often the enemy of the good. Many dentists, physicians, and discriminating patients, seek microscope enhanced, minimally invasive, and monolithic Bioclear composites. None of them ask for layered composites. What do patients want? Colour uniformity, bright but believable colour, no cutting of the tooth, no porcelain, no tissue inflammation, no black triangles, no staining, no roughness, no fractures and an assurance that the restoration will be as strong as porcelain. My office guarantees Bioclear restorations for ten years against stain and de-bonding. In contrast, my office warranty on porcelain is five years. While I don’t suggest that doctors using Bioclear should offer a ten-year warranty, doctors should be confident that these over-molded restorations should hold up as well as porcelain. Most dentists, myself included, can’t satisfy that list with hand stacked multi-shade composite. It is important to note that the driving forces are the patient and the soft tissues. Masters of layering, such as Dr. Bob Margeas and Dr. Jeff Brucia, have extraordinary long-term results but they will freely admit that layering is more artistic than what is asked for by patients. In reality, most dentists who dabble in layering often have problems and find the procedure to be a labour of love that is unprofitable and disappointing to patients. If you love to layer and are good at it, then you can certainly layer with the Bioclear Matrix. If not, say goodbye to layering.

Just say no to translucency
This case, as most are in my practice, was restored with Filtek Supreme Ultra Body flowable and regular composite. The most popular shade for my office is B-1. We have most patients do tray bleaching before the teeth are restored, which allows the routine use of B-1 body composite. We don’t use enamel shade, dentin shade, or translucent shade. The 3M body shade is a perfect balance of translucency and opacity, and its use allows me to focus on more important issues, like shape and strength. The flowable matches the regular composite perfectly.

Details of the Case
The brevity of this article does not allow a complete description of the case. However, a narrated video is available at the Bioclear online learning center. This video, shot through the lens of a global microscope in full HD, has an abundance of tips and fully explains the sequencing issues.

Blasting
Blasting is not air abrasion, which uses very aggressive aluminum oxide. In order to adequately remove biofilm, the teeth are painted with disclosing solution and then meticulously blasted with pressurized aluminum tri-oxide/water mix (Bioclear Blaster, Clinical Research Dental). Clinicians must be reminded that phosphoric gel etchant alone cannot be relied upon to remove plaque to achieve an ideal bond to enamel or dentin. Rubber dam utilization is often dismissed for anterior esthetics as unnecessary or worse, counterproductive. As developer of the matrix, I have found that in most cases the amount of interproximal gingival retraction afforded by the rubber dam is ideal for predicting the amount of static tension needed to generate or regenerate a papilla. The rubber dam also protects the soft tissues when blasting is performed to remove pesky biofilm.

Once the central incisors were over-molded using Bioclear A-101 and a-102 matrices (not pictured), they were measured and sculpted with a rough finish (Fig. 9). The rest of the left side was completed one tooth at a time, and then the same with the right side. Tooth #12 shows several steps (Figs. 10-15).

FIGURE 9. The pre-polished width of the central incisors is measured before moving on to #22 and #23. Central incisors must match perfectly.

FIGURE 10. Two trimmed Bioclear DC203 matrices are placed on the mesial and distal of #12. It creates a crown like containment system.

FIGURE 11. 37 percent phosphoric acid gel is beginning to be injected into the matrices. Make sure to inject apically to get a ­complete etch.

FIGURE 12. The entire tooth is etched for 20 seconds and then rinsed thoroughly and dried.

FIGURE 13. Adhesive is quickly painted completely over the tooth, air thinned but not light cured. When there is little to no dentin involved it is better not to cure the adhesive independently of the composites.

FIGURE 14. The tip of the flowable composite is inserted 360° around the gingival margin, facilitated by the wetting action of the yet to be cured adhesive.

FIGURE 15. High magnification view of the initial placement of composite. This “flowable composite hip” was not individually light cured in this case because these post-orthodontic teeth are a little mobile. The radius of the matrix actually allows the matrix to push the teeth apart slightly so that no delayed wedging will be necessary.

 The Clark 3 Step Polish
The Bioclear method is unique in that the loading zone is left with intentional excess. While the difficult areas, such as the interproximal and subgingival, are essentially porcelainesque by virtue of the Mylar finish. The goal is to then safely and quickly grind back the loading zone, do a matte finish on only the injection zone with a coarse disk, and marry it to the glassy, smooth Bioclear Mylar finish zone. The three step polish is: 1) Shofu Brownie with water coolant at medium speed on the lingual only, 2) coarse lab pumice in a disposable cup and, 3) The Shape and Shine cup by Clinical Research Dental (Fig. 16).

FIGURE 16. Once the regular composite has been injected into the pool of uncured flowable composite, the tooth is contoured in the loading zones and finally polished with the Shape and Shine polisher.

Post-operative views reveal a patient-friendly, strong and incredibly stain resistant finish (Fig. 17). In Figure 18, the reader should carefully study the thickness of the teeth. Our research and follow up studies have shown that if the incisal edge of the composite is at least 1.5 mm thick, and the entire tooth is over-molded, we can expect zero incisal edge fractures. In the same way that monolithic porcelain like lithium di-silicate (EMax Press) and full Zirconia crowns just don’t break, monolithic (non-layered) Bioclear method composite overmolding produces surprising durability. Unlike many of the porcelain veneer cases presented in past dental journals, most of today’s porcelain veneers in hometown dental practices are fabricated as monolithic (one single shade/type) porcelain, with either pressed or milled porcelain. While these monolithic porcelains are durable, they are generally more monochromatic than the older style, hand stacked porcelains. Any significant multichromaticity is achieved with staining that has a limited lifespan. In short, we have moved to color uniformity. Patients like it and dentists love the strength. I use the words colour uniformity and not monochromatic in a purposeful way. Patients prefer colour uniform teeth, so I have changed the lexicon to reflect the new thinking.

FIGURE 17. Retracted three week post-operative view of the composite over-molded dentition.

FIGURE 18. Occlusal post-operative view. Note that the buccal-lingual thickness of the teeth is sufficient to give porcelain-like strength. Recommended thickness is 1.5 to 2 mm.

In the past 24 months, I have placed hundreds of Bioclear over-molded anterior composites and have seen essentially zero incisal edge fractures. Layering and patchwork creates compromised strength. Composite overmolding, in contrast, produces extraordinary toughness. And not a single patient has wanted translucent incisal edges of those hundreds of teeth. Better, faster, prettier and stronger composites is the new catchphrase that we embrace.

Bioclear over-molded composites versus porcelain is the new big question. Here is a good rule of thumb: age matters. We know that a lifetime of occlusion will selectively wear down the enamel lower incisors if we use porcelain. If the patient is under 40, I suggest composite first. Any time I am only doing a limited case of one to three anterior teeth, composite is again preferred because trying to prepare and match one or two porcelain laminates to natural teeth can be very invasive and the colour matching can be excruciating and a profit killer. After age 40, and in the case that I will do six to ten teeth, we tell the patients that either porcelain or composite is great. The true infinity edge (feather edge on non-prepared enamel) margin is only possible with direct composites. A composite margin can easily be thinned and polished to have an almost microscopically imperceptible margin. Composites’ infinity edge benefits both colour matching and pink esthetics, and nearly always has better gingival health than microscopically fitted porcelain margins.

What did the patients and parents think?
Mom reports that upon completion of the restorations, random people often stop the twins in the street and say, “you two have the most beautiful teeth I’ve ever seen”. The family notes that their facial posture is different now. Patchwork bonding rarely produces such life altering dental makeovers. Today, a modern approach to composite with the Bioclear method can have the same face-changing and life-altering effect as po
rcelain rehabilitation.

Summary
There are six new factors that have changed the game in additive dentistry. These are: modern resin design, breathtaking composite polishing, heated composite, Bioclear anatomic and diastema closure matrices, injection overmolding combining flowable and regular composite, and the trends away from both layering and incisal translucency. While some training is helpful and doctors are encouraged to take a hands-on course at the Bioclear Learning Centers, (Toronto, ON & Tacoma, WA, USA) many clinicians just jump right in and teach themselves. Either way, these techniques should be within the grasp of most clinicians – especially those who use magnification. A narrated video detailing the twins’ treatment, shot through the Global microscope along with other technique videos, is available online at Bioclearmatrix.com.

Disclaimer
Dr. Clark is the creator of the Bioclear Matrix system and has a financial interest in this product.


Dr. Clark founded the Academy of Microscope Enhanced Dentistry. He is a course director at the Newport Coast Oral Facial Institute and the Director of the Bioclear Learning Center in Tacoma, WA. He can be reached at drclark@bioclearmatrix.com. Contributing orthodontist, Dr. Jerrold S. Johnson, can be reached at drjohnson@naumannjohnson.com.

Oral Health welcomes this original article.

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