When reading the beginning of the Robert Frost poem The Road Not Taken, you are standing at a fork in a road deciding which path to take. One path is obviously more worn, and thus traveled by more people. Conversely, the other path is less worn and traveled by fewer people. When a patient comes to your office for a smile makeover, the most common path taken is porcelain veneers. This article will discuss another path to take.
THE IDEAL SMILE MAKEOVER
What characteristics would your ideal smile makeover procedure have? What would it involve? No aggressive veneer preps? No intentional endodontics? Less crown lengthening needed? Creating incredible patient comfort? No large lab fees? If you answered yes to any of these questions, then the orthodontic concept described in this article should be very applicable to your practice.
Figures 1a to 1d. A variety of case types can be treated with the PPSMB. |
The concept and techniques described below (Powerprox Six Month Braces Technique [PPSMB]) allow the practitioner
to use conservative treatment to easily achieve great smiles quickly. It can be utilized to treat many kinds of cases including, but not limited to, crowding, spacing, deep bites, cross-bites, and open bites (Figures 1a to 1d).
MOVING TEETH VERSUS CUTTING THEM
Figures 2a to 2d. The goal in these cases was to give the patient a great smile quickly and conservatively. |
The goal of porcelain veneers is to give your patient a great smile. The goal of the PPSMB is the same, except we are just taking a different road to get there. Instead of preparing the teeth and bonding porcelain, we move the teeth to their most beautiful position. However, this technique is more analogous to porcelain veneers than it is to comprehensive orthodontics, to which it is often mistakenly compared. Once again, the primary goal of both the PPSMB and porcelain veneers is anterior cosmetic correction. That isn’t to say that we do not change the posterior occlusion at all with this technique, because we do. As a matter of fact, we can open deep bites very quickly. This is one of the advantages that this new orthodontic technique has over porcelain veneers. Our primary focus is not skeletal and occlusal perfection; our goal is a great smile—the same goal that we have with porcelain veneers (Figures 2a to 2d).
ROAD MAP TO A BEAUTIFUL SMILE
Once on the “PPSMB road” we need to make a few stops before we reach our final destination. These stops in the road are part of what we call The Powerprox Flow-chart. This is a very organized and systematic way to go from information gathering, to diagnosis, to treatment planning, to treatment execution.
Figures 3a and 3b. Powerprox Flowchart. |
The first stop is taken to gather our diagnostic information. This includes a TMJ and orthodontic examination, a panoramic film, a lateral cephalometric film, study models, and a photo series. This diagnostic information, along with information obtained from medical and dental histories and a patient consultation/interview allows us to move to the next stop in the road. At the next stop, we list our diagnostic concerns obtained from the diagnostic information. Moving down the road, we prioritize these concerns in decreasing order of importance. The patient’s chief complaint has a direct effect on the order. The next stop is to formulate our treatment goals. We need to discuss not only what we will correct, but also what we will not correct. This is an important step, as the patient must be properly informed of both. At our next stop we list our solutions to the diagnostic concerns. Finally, we develop a written treatment plan and then execute that plan. When the plan is executed, we reach our goal at the end of the road—a great smile (Figures 3a and 3b).
BUMP IN THE ROAD? IS ROOT RESORPTION A MYTH?
One of the largest areas of confusion and misinformation in orthodontics pertains to the cause of root resorption. Simply stated, the primary cause is genetics. You are either prone to it, or not. Let’s discuss this often-misunderstood topic further.
Reports of root resorption date back almost 150 years. Bates,1 in 1856, was the first to discuss root resorption of permanent teeth. Apical root resorption is a common finding, with or without orthodontic treatment. In fact, Harris2-5 reported that resorption was present in about 10% of teeth that had not been orthodontically treated, and that 1% to 2% demonstrated severe resorption, mostly in the upper incisors. It has been suggested that root resorption has always existed as a normal repair phenomenon. Unfortunately, there is no way to predict which patients are at risk for root resorption. It has many etiologic factors, and many of these are beyond our control. In fact, Brezniak and Wasserstein6,7 performed an extensive review of the literature in 1993. They considered several biologic, mechanical, and clinical factors, and concluded that no clear cause for the severe root resorption, which sometimes occurs during orthodontic treatment, could be found. In fact, many studies of large sample size have not identified conclusive causative factors of root resorption.6,7
It is thought that most patients undergoing orthodontic treatment will have some degree of root resorption. Fortunately, resorption very rarely occurs to such a degree that it causes a problem. In fact, spontaneous loss of a tooth from root shortening has not been reported in the literature. Let’s examine this further. Kalkwarf, et al8 analyzed the amount of periodontal attachment loss from root resorption. They showed that 4.0 mm of root loss from root resorption resulted in just 20% attachment loss. Investigators have stressed that root resorption is less critical than crestal bone loss, in terms of periodontal support; 3.0 mm of apical root loss is equivalent to 1.0 mm of crestal bone loss.
There has been considerable debate about force levels’ effect on root resorption. Owman-Moll, et al9 found that there was no difference in root resorption severity when the force was doubled from 50cN to 100cN. Whereas Parker and Harris10 reported that when high levels of force are used, or applied in an undesirable direction, ie, jiggling forces, this can give rise to root resorption. There is much more agreement that treatment duration is a bigger factor in root resorption. Sharpe, et al11 found that patients who had undergone longer periods of treatment had greater prevalence of root resorption. Put simply, longer treatment times are associated with more roots shortening than shorter treatment times.
Some additional factors that have been suggested to increase root resorption include the use of class II elastics. Linge and Linge12,13 found wearing class II elastics is associated with a higher risk of root resorption. Also, teeth with periodontal disease showed higher risk than teeth without attachment loss.12,13 According to Kaley and Phillips,14 patients with a class I occlusion and acceptable overjet were less likely to have root resorption. This was most likely due to the smaller amount of tooth movement necessary to achieve the desired final result. Patients being treated for class II, class III, open bites, or bicuspid extraction cases are more likely to have root resorption due to the larger distances the teeth have to travel.14 Horiuch, et al15 reported that an additional risk factor could be the amount of lingual root torque and the approximation of the maxillary incisor root apices against the cortical plate. This is thought to increase the chance of root resorption by up to 20 times.15
The good news is once orthodontic treatment has stopped, any root resorption stops. In most patients root resorption is minor and not clinically significant. If there happens to be more extensive root resorption, the chance of tooth loss is minimal.
COMBINING REPROX AND NICKEL-TITANIUM ARCHWIRES
Figures 4a and 4b. Reprox and nickel-titanium archwires work synergistically together to correct severely crowded teeth quickly. The combination of reprox and nickel-titanium gave us this result in less than 3 months. |
Figures 5a and 5b. Compare the amount of enamel removed from Reprox to that of a typical veneer case. The PPSMB is a conservative, minimally invasive treatment. |
As mentioned earlier, a great variety of cases can be treated with the PPSMB, but the most common case is one with crowding. The powerful, yet gentle, combination of reprox and nickel-titanium archwires work synergistically to align even severely crowded teeth. Crowding is a discrepancy between the mesial-distal width of the teeth and the length of the dental arch. So, it stands to reason that if we could reduce the width of the teeth, we could alleviate crowding within the dental arch.
Reprox, also known as stripping or IPR (Interproximal Reduction), has a long history in orthodontics and is a very safe and a very conservative way to create space to move teeth. There is far less enamel removed when performing reprox in a typical PPSMB case than there is when preparing the teeth in a typical porcelain veneer case (Figures 4a to 5b).
Reprox is very simple to perform and can be accomplished with diamond strips, carbide burs, or diamond burs. We have found that the fastest and easiest way is to use a diamond disk interproximally, followed by smoothing with a finishing bur and then final finishing with a diamond strip. This quickly, easily, and painlessly creates the room required to move the teeth. On rotated teeth, you do not use the disk, since you could alter the facial or lingual aspects. You want interproximal reduction only, in effect “shrinking” the teeth. So, in the case of rotated teeth a finishing bur directly on the mesial or distal side of the tooth works best (Figure 6).
Figure 6. By disking through the contact point and subsequently polishing the area, one can quickly, safely, easily, and conservatively achieve room to move teeth. |
Figure 7. Note the extreme flexibility of nickel-titanium archwires. This allows one to easily tie wires into severely crowded teeth. |
Figures 8a and 8b. The strength and flexibility of nickel-titanium coupled with reprox allowed for this dramatic improvement in a few months. |
Now that we have created space, the next step is to move the teeth into position. We use nickel-titanium archwires for this purpose. Nickel-titanium archwires have wonderful physical properties that make them a great fit with the PPSMB. The main property it has is shape memory. That means no matter how it is bent, twisted, or deformed it will return to its original shape. It does this with a continuous, sustained force that allows for very efficient tooth movement that is also very comfortable for your patients. In addition, it is also highly flexible, which means you can tie it into severely crowded teeth very easily. In essence, you tie this flexible nickel-titanium archwire into crowded, rotated teeth and it regains shape memory, and takes the teeth along for the ride (Figures 7 to 8b).
COMBINATION CASES
Figures 9a and 9b. Combining the PPSMB with cosmetic dentistry made this difficult case easy. |
There are times when we combine PPSMB with cosmetic dentistry to get a nicer result than can be obtained by either alone. Combining the two has advantages: it allows for more conservative veneer preps, reduces the need for cosmetic crown lengthening, reduces or eliminates the need for intentional endodontics, and makes that “impossible” case doable (Figures 9a and 9b).
REACHING THE FINAL DESTINATION
When you are standing at that fork in the road deciding which path to take to give your patient a great smile, hopefully you will now give some serious consideration to a path currently less taken—The Powerprox Six Month Braces Technique. It is a fast, safe, and conservative treatment alternative to a porcelain veneer smile makeover. In the author’s opinion, providing this service would be a positive step taken on the path to optimal care for your patients and your practice.
References
- Bates S. Absorption. Br J Dent Science. 1856;1:256.
- Harris EF, Boggan BW, Wheeler DA. Apical root resorption in patients treated with comprehensive orthodontics. J Tenn Dent Assoc. 2001;81:30-33.
- Harris EF, Butler ML. Patterns of incisor root re-sorption before and after orthodontic correction in cases with anterior open bites. Am J Orthod Dentofacial Orthop. 1992;101:112-119.
- Harris EF, Robinson QC, Woods MA. An analysis of causes of apical root resorption in patients not treated orthodontically. Quintessence Int. 1993;24:417-428.
- Harris EF, Kineret SE, Tolley EA. A heretible component for external apical root resorption in patients treated orthodontically. Am J Orthod Dentofacial Orthop. 1997;111:301-309.
- Brezniak N, Wasserstein A. Root resorption after orthodontic treatment: Part 1. Literature review. Am J Orthod Dentofacial Orthop. 1993;103:62-66.
- Brezniak N, Wasserstein A. Root resorption after orthodontic treatment: Part 2. Literature review. Am J Orthod Dentofacial Orthop. 1993;103:138-146.
- Kalkwarf KL, Krejci RF, Pao YC. Effect of apical root resorption on periodontal support. J Prosthet Dent. 1986;56:317-319.
- Owman-Moll P, Kurol J, Lundgren D. The effects of a four-fold increased in orthodontic force magnitude on tooth movement and root resorptions. An intra-individual study in adolescents. Eur J Orthod. 1996;18:287-294.
- Parker RJ, Harris EF. Directions of orthodontic tooth movements associated with external apical root resorption of the maxillary central incisor. Am J Orthod Dentofacial Orthop. 1998;114:677-683.
- Sharpe W, Reed B, Subtelny JD, et al. Orthodontic relapse, apical root resorption, and crestal alveolar bone levels. Am J Orthod Dentofacial Orthop. 1987;91:252-258.
- Linge L, Linge BO. Patient characteristics and treatment variables associated with apical root resorption during orthodontic treatment. Am J Orthod Dentofacial Orthop. 1991;99:35-43.
- Linge BO, Linge L. Apical root resorption in upper anterior teeth. Eur J Orthod. 1983;5:173-183.
- Kaley J, Phillips C. Factors related to root resorption in edgewise practice. Angle Orthod. 1991;61:125-132.
- Horiuchi A, Hotokezaka H, Kobayashi K. Correlation between cortical plate proximity and apical root resorption. Am J Orthod Dentofacial Orthop. 1998;114:311-318.
Suggested Readings
Ballard ML. Asymmetry in tooth size: a factor in the etiology, diagnosis and treatment of malocclusion. Angle Orthod. 1944;14:67-70.
Boese LR. Fiberotomy and reproximation without lower retention, nine years in retrospect: part I. Angle Orthod. 1980;50:88-97.
Boese LR. Fiberotomy and reproximation without lower retention 9 years in retrospect: part II. Angle Orthod. 1980;50:169-178.
Crain G, Sheridan JJ. Susceptibility to caries and periodontal disease after posterior air-rotor stripping. J Clin Orthod. 1990;24:84-85.
El-Mangoury NH, Moussa MM, Mostafa YA, et al. In-vivo remineralization after air-rotor stripping. J Clin Orthod. 1991;25:75-78.
Levander E, Malmgren O, Eliasson S. Evaluation of root resorption in relation to two orthodontic treatment regimes. A clinical experimental study. Eur J Orthod. 1994;16:223-228.
Peck H, Peck S. Reproximation (enamel stripping) as an essential orthodontic treatment ingredient. In: Cook JT, ed. Transactions of the Third International Orthodontic Congress held in London, 13-18 August 1973. London, England: Crosby Lockwood Staples; 1975:513-522.
Proffit WR. Contemporary Orthodontics. St Louis, MO: Mosby; 1986.
Sheridan JJ. Air-rotor stripping. J Clin Orthod. 1985;19:43-59.
Sheridan JJ. Air-rotor stripping update. J Clin Orthod. 1987;21:781-788.
Tuverson DL. Anterior interocclusal relations. Part I. Am J Orthod. 1980;78:361-370.
Dr. DePaul has been providing orthodontics to his patients since 1994. His passion for the topic led to intense study and research in the field of orthodontics. He is a world-reknown authority on the Powerprox Six Month Braces Technique. He has authored several books, DVDs, and CDs on the subject, and has taught countless doctors through his books, articles, and seminars. His goal is to spread life-changing orthodontic techniques throughout the dental community. He can be reached at (440) 646-1000 or by visiting sixmonthbraces.com.
Disclosure: Dr. DePaul owns the trademark for the Powerprox Six Month Braces Technique and has a financial interest in the sale of educational materials regarding the Powerprox Six Month Braces Technique (PPSMB).