FAQ

Frequently Asked Questions

· From Dr. R. G. "Wick" Alexander:

· FREQUENTLY ASKED QUESTIONS in orthodontics

· As I travel around the world sharing my philosophy of orthodontics to many audiences, I am always asked many questions concerning the various subjects.Often these are noteworthy questions whose answers should be in the text of the lecture. Since our web site is read by hundreds of orthodontists around the world, I felt it would be an interesting idea to create this column to share these questions and answers with each other. It is my desire that you will not only read this information, but also question me on subjects that are of interest to you. One thing you can be for sure … if I know the answer, I will attempt to explain it in such a manner that it will be easy to understand. If I do NOT know the answer, I am very good at saying, “I don’t know.”

· So what questions do you have about our technique … or orthodontics in general? I look forward to sharing my thoughts with you.

F.A.Q.

· Is it possible to determine the most suitable age for starting an orthodontic treatment and if it is, why?

· Remember that there are exceptions to every rule, but in general this is my advice. The most suitable age for starting orthodontic is when all primary teeth have exfoliated, except the primary mandibular second molars. Why? In many borderline cases, utilizing the "E Space" will allow the case to be treated nonextraction.This space of approximately 3 - 4 mm can be captured by placing a lingual arch and hold until the permanent second bicuspids have erupted. If additional space is needed, a lip bumper can gain another of 3 - 4 mm.

· Which malformations do you start treating early dentition and which do you monitor until permanent dentition?

· One of the most common mistakes we make in orthodontics is starting treatment too early. Although it is difficult to resist that initial down payment, in the long run, everyone will be better off if treatment is delayed. Certain cases, however, should be treated early. If delaying treatment will cause the malocclusion to deteriorate, if it will get worse without treatment, early treatment is desired. Such cases include anterior crossbites. Posterior crossbites, unless severe, can be treated later.Also, if an extreme overjet is present, treatment is indicated to protect the teeth as well as possibly improve the patient's self-esteem. Extracting primary mandibular cupids prematurely is a BIG mistake ... unless you plan to extract permanent teeth later. My advice is to not extract these teeth early. They are "holding" the bone where the permanent cupids will erupt.

· What is the risk of relapse by an early orthodontic treatment? Should it then be considered as an unsuccessful treatment? What should we clarify to the parents of a young patient before we start the treatment?

· The risk of relapse in early treatment is very high. Asking a patient to wear retainers during this interim period between fist and second phase is very difficult and time consuming for patient and doctor. Parents should be aware that this early phase is just the beginning. Final results will be not achieved until the patient is approximately fourteen years old. Total cost is greater than delaying treatment and treating only one phase, when permanent teeth have erupted. "Timing is everything." As I reflect on my early treatment history, there were many times when I should have delayed treatment but instead ending up treating the patient for 5 to 6 years. Upon evaluation, I could have achieved similar results by delaying treatment and treating in one phase only.

· How do you analyze the causes of a relapse case, are you searching for your own mistakes in the treatment plan; is it unfavorable skeletal growth; or is it inadequate choise of appliance and treatment approach?

· Relapse: The eternal question ... what causes orthodontic relapse? We like to blame it on unfavorable growth, muscular habits, wisdom teeth, poor cooperation, mesial drift. Of course, each of these factors can have a negative influence on the patient's stability. But the reality is that with most patients, if the proper goals are achieved in treatment, the possibilities for stable results are very real. The reason most cases relapse is that the teeth are placed in unstable positions during treatment.

· Should the orthodontist be afraid when entering the room of truth, finding our faults he had made in a treatment or should this help him expand his knowledge? Do you think that mistakes, when analyzed, lead to the further development of Orthodontics?

· Do not be afraid of the "Room of Truth." It should be just the opposite! With 10,000 sets of diagnostic records to study, we are finding more and more evidence-based knowledge that is telling the "truth." Often, we learn more from our mistakes than from the excellent results. The door is always open to anyone, regardless of their beliefs, to evaluate these cases. I want to discover the truth, regardless of any particular technique or belief system.

· What reasons made you innovate the “Alexander System”?

· This is almost a question regarding my "purpose in life." :) The Alexander Discipline has been evolving throughout my orthodontic career. My early training in the Tweed technique gave me a solid foundation, but I was not happy with the mechanics, too many extractions and good results that were so difficult to achieve. So I began searching for a "better way." The technique I discovered is simple. No complicated archwire multiloops. We use a sequence of archwires that is repeatable in most cases. The bracket design and archwires are programmed to move the teeth directly into their desired positions. How is this accomplished? Increased interbracket space created by single brackets allows more flexibility when engaging archwires. Rotational wings correct rotations quickly and hold them in their corrected positions. .018 bracket slots will give accurate torque control when finishing with the recommended 17x25ss archwires.

· Would you clarify the advantages of the “Alexander System” compared to the other vestibular fixed techniques?

· The Advantages of the Alexander System: "Begin with the end in mind." To my knowledge, no technique has had more research (over 50 studies) using the author's own cases to demonstrate its long term results. If used as instructed, this technique produces the most stable results in orthodontics. But what makes it so nice is that achieving these results is quite simple. All that is necessary is to "follow the rules. "These rules are specified in my new book, "The 20 Principles of The Alexander Discipline," published by Quintessence. Like everything in life, it does take discipline! For example, you should learn how to bend omega loops and tie back the archwire with a ligature tying pliers. Early in treatment, the flexible archwire with the additional interbracket space will produce a very low friction force on the teeth. At the end of treatment, the 17x25 ss archwire in the .018 slot will produce high friction for proper torque control, tooth angulation and off-sets. If the Alexander brackets are placed properly, beautiful results will routinely be achieved. In the near future, I am hoping to design a self-ligation bracket for our system. But rest assured that I will not sacrifice quality for expedience. It will still produce the same results we are achieving now. Patient compliance is critical. Motivating patients to achieve their goals is one of the joys of my life. Not only does this improve the final results, but it is a tremendous learning experience for the patient. Effort = Results.

· Which recommendations would you pass on to the orthodontics so that they could obtain a steady and lasting treatment?

· 1. Control lower intercanine width

· 2. Ideal mandibular incisor position

· Where is the most stable positing? During years of my clinical observation, “stable” is the position in which the patients presents. A stable range for mandibular incisors can be from 70 degrees to 110 degrees. Many orthodontists do not pay sufficient attention to torque control of the mandibular incisors. When the mandibular incisors are indiscriminately tipped or advanced, the doctor is creating a danger for potential relapse. The health of the dentition and gingival tissue are also affected when the mandibular incisors are not positioned well. Some orthodontists retract the teeth lingually. This retraction creates an aesthetic problem with the facial profile resulting in a dished appearance.

· 3. Control flaring of lower incisors

· The flaring of lower incisors is prevented by – 5 degree lingual crown torque of labial root torque in the lower incisor brackets. The initial rectangular archwire placed on the arch should be .17” x .25” D-Rect multi-stranded archwire or .17” x .25” CuNiTi archwire to give an appropriated torque on the lower anterior brackets. The effect of -5 degree torque, the rectangular initial wire and -6 degree angulation on the first molar are to hold the mandibular incisors in their original position. If the mandibular incisors are tipped lingually before treatment, a zero degree torque brackets should be placed on the lower incisors. Anytime the doctor does not require this negative torque, it can easily be deactivated using smaller rectangular or round archwire. Another way to control flaring of lower incisor is to make IER on the anterior teeth, mainly in the lower incisors crowding cases. When the mandibular incisors are tipped labially, the doctor can place class 3 elastics to hold lower incisors. This should be addressed the day of bracket placement. (Keep in mind vertical anchorage to maintain maxillary posterior teeth in their position using Extra Oral Appliance(High Pull), transpalatal bar and other appliances for vertical control).

· 4. Spread apart the roots of the lower anteriors

· The mandibular laterals should be positioned with more angulation(+6 degree) in order to improve stability. Thus, the lower lateral roots will be aligned more parallel to the cuspid root, decreasing the rate of relapse. Clinical observation of my post–treatment patients over the years had led me to agree that one of the causes of relapse in the mandibular anterior arch has been the poor artistic positioning of the mandibular lateral incisors.

· 5. Good interincisal angle

· An ideal interincisal angle must be established during treatment by controlling torque on the mandibular and maxillary incisors.

· 6. Upright lower 1st molars

· The long-term stability of deep bite cases is also related to the ability to upright, or tip back, the mandibular first molars achieved by placing an angulation of -6 degree on the 1st molars. By uprighting the first molars, the anterior arch length is increased, the second premolars are simultaneously extruded to help level the mandibular arch, and the posterior occlusal stops are established to prevent anterior overbite relapse.

· 7. Obtain good buccal occlusion by sectioning posterior archwires and using finishing elastics.

· 8. Retain until through growth due to remanescent cranial base growth

· 9. Enamel reduction of lower anteriors after removal of 3 x 3

· This procedure allows for future anterior and lingual migration of the cuspids without concurrent mandibular anterior recrowding. Furthermore, slenderizing remodels the mandibular anterior interporximal contact points into contact surfaces. This situation helps to maintain mandibular anterior alignment.

· 10. Musculature

· The question is “Can muscle pressure influence tooth position?” Many studies( ) have been shown that tooth stability are directly influenced by muscle balance existed between the tongue on the inner side of the dental arches and the muscles surrounding the outer side of the dental arches. Muscle function must be regarded as a dominant factor to keep tooth in their balanced position. Muscular habits, such as tight lip musculature, placid lip musculature, mouth breathing, tongue thrusting, and sucking habits(thumb sucking lip biting, nail biting) can place abnormal forces upon the dentition to cause significant relapse. This is the reason to eliminate these habits as early as possible in treatment.

· 11. Overcorrection of rotation & Circumferential Supracrestal Fiberotomy

· After correction, a severely rotated tooth has a tendency to return to their original position due to the memory of transeptal fibers. These fibers are stretched during treatment and after appliances are removed, the fibers tend to contract returning the teeth toward to their original position. Post-treatment and post-retention relapse are minimized in adolescent patients with crowded pretreatment conditions, holding their teeth with retainers after treatment. The fibers seem to reshape to a new dental configuration easily. However, when maxillary laterals are positioned lingually prior to treatment, a significant tendency for relapse remains. Another case include a severe rotated teeth and previously impacted teeth. In adult patients a reconfiguration of the transseptal fibers is slow compared to adolescent patients during active treatment and retention. For this reason the circumferential supracrestal fiberotomy is a routine procedure. This surgery is preformed six weeks prior to appliance removal. Thus, the transseptal fiber memory is reduced, preventing significant relapse. Circumferential Supracrestal Fiberotomy should be done after correction of any preorthodontically rotated teeth, especially maxillary and mandibular anterior teeth. The procedure should be done before debonding after mild(3 degree to 5 degree) overcorrection.

· 12. PRAY!

· Considering your professional way of acting clinically, which duties do you consider of importance besides the diagnosis and treatment plan and which ones would you delegate to the auxiliary staff?

· One of the most appealing things about orthodontics is the ability to DELEGATE. The problem occurs when this opportunity is abused. In general, my thinking has always been to delegate anything that I can train a staff member to do as well or better than I can do.

· This includes removing the archwire and bending omega loops in the new wire, then ligating the archwire into the patient’s brackets after the doctor has checked it. BUT the doctor must be in charge! Bracket placement and cementing orthodontic bands is critical and should not be delegated. Developing the arch form, placing curve, etc., can only be accomplished by the doctor.

· After the doctor has adjusted the facebow, the assistant can instruct the patient on the placement of the facebow, elastics, and strap.

· Oral hygiene education is the job of everyone on the staff.

· The key is to find a person who has “good hands” and enjoy working with people, then train them properly before they begin to work on patients. Then supervise them closely until you are confident in their ability. A well trained staff is a key component to a successful orthodontic practice, but it is like all other things ins life… it takes EFFORT!

· What would your advice be to the young orthodontist in the beginning of their careers, in the sense of achieving a good clinical level and credit on their clinical function?

· Have priorities in your life. What are really the most important things in your life? Health, family, religion, profession.

· Learn the fundamental of orthodontics …understand functional occlusion and the MECHANICS of bending wire to produce torque, tip, offsets, up & down. How to correct skeletal discrepancies in growing patients.

· Understand growth and development so that you can DIAGNOSIS the problem accurately.

· TREATMENT PLANNING – know what works to achieve your goals and how to reach them.

· Learn the GOALS for long term stability and strive to achieve them in every case.

· The last 6 months of treatment is the most critical. Learn how to FINISH the case!

· Learn how to MOTIVATE the patient to follow your instructions. The orthodontist is only as good as his/her patient.

· Don’t be misled by the promoters who say things that sound too good to be true… because they are.

· In summery, apply the knowledge you have acquired, go slowly, study your own results and find what works vest for you. And always remember to treat each patient as if they were your own child!

· Which recommendations would you pass onto the orthodontists so that they could obtain a steady and lasting treatment?

· STABILITY

· Obtain a good buccal occlusion

· In my technique, certain procedures are essential to create an ideal buccal occlusion at the end of treatment. The final detailing and settling in the posterior and anterior area is carried out by sectioning the archwire and wearing up-and-down finishing elastics. The maxillary and mandibular arch is sectioned usually between the cuspids and first bicuspids depending on the individual case. After sectioning, the archwire is removed posterior to the cuspids on both sides of the arch in order to leave these teeth free to move vertically. The anterior sections remain in the arch allowing correction of remanescent torque control and rotations. Zig-zag elastics are wearing depending on the case.

· If the original malocclusion was a Class II deep bite case, the lower arch only is sectioned. The archwire is bent distal to the cuspids. A ¾ inch, 2 ounces round elastic I attached in each posterior segment. In a Class II case, these up-and-down elastics are attached on the maxillary lateral incisor(extraction case), or the maxillary cuspids(non-extraction) and continues through the second maxillary and mandibular bicuspids creating a “W with tail” elastic configuration. The posterior up-and-down elastics will deliver an extrusive force to the mandibular bicuspids and molars area in order to help improve or maintain a level lower arch. It is important to understand that most of deep bite cases demonstrated a severe curve of Spee.

· Consequently, the bite will be stabilized so that the overbite will be less likely to relapse after treatment. This design creates a Class II vector in order to close down the buccal segments. The up-and-down elastics should be wearing for two weeks before sectioning the upper archwire. The elastics should be worn for two weeks and the appliance can be removed.

· In an open bite or Class III tendency, the upper archwire is first sectioned. Some curve of Spee have been placed in the lower and upper arch. The up-and-down elastics are worn in the “M with a tail” design creating a Class III vector. The up-and-down elastics are attached on the mandibular canine, continue through maxillary canine until upper second bicuspid and worn for two weeks. The same procedure is carried out as observed for Class II cases. In a Class I case, both arches may be sectioned and the patient wears an “M with a tail” or “W without a tail” depending upon the need. The doctors will decide which posterior segment should be extruded before sectioning the archwire. The anterior overbite/overjet relationship is corrected wearing anterior up-and-down elastics with a Class II or a Class III vector, or anterior box elastics.

· Why use Single Brackets rather than Twins?

· In orthodontics, the amount of force placed upon the teeth will affect the movement of these teeth. Teeth will move in three dimensions … 1) Labio-lingually, 2) Inciso-gingivally, and 3) Mesio-distally. The challenge is to move the teeth into their desired positions in a direct path with the smallest amount of force possible.

· The first decision is to determine where the teeth should be at the end of treatment …your treatment goals. Then proper mechanics should be employed to gently move those teeth into these predetermined positions.

· In a “fixed” appliance, teeth can be moved by first placing brackets on the teeth, then inserting an archwire into these bracket slots. The archwire will deliver the forces to move the teeth. So, the amount of movement and direction of movement of the teeth is determined by the bracket design and the archwires used.

· Another factor that may have a limited effect upon the tooth movement could be the intraoral muscular forces. It is well known that orthodontic forces can overpower the muscular forces during treatment; however, after treatment and retention, the muscles will move the teeth back to their balanced positions.

· The Value of Interbracket Space

· What is the difference in using twin brackets and single brackets?

· Basically, it is the difference in the amount of space between the brackets. This is called interbracket space. Why is this important?

· Does it really make any difference if the space between brackets is greater or less?

· Clinically, I routinely see that early in treatment the teeth align themselves very quickly with little discomfort to the patient.

· Is this a result of interbracket space? If so, why?

· Mechanical engineers will tell you that the rate between the load (Force) and application distance (d) is inversely proportional to the 3rd power of the distance (1/d)³. If the other variables remain constant (wire stiffness, length, elasticity modulus), when the distance between brackets is increased two times, the force applied would decrease EIGHT times. F= (1/d) ³ = (1/2) ³ = 1/8 “Load /Deflection rate of any wire is directly proportional to the diameter of the wire and inversely proportional to the third power of the length of the spring (longer wire = less stiffness to the 3rd power)” – Dr. Marcotte Clinically, this means that by using the same archwire on two patients, one using twin brackets and the other using single brackets, doubling the interbracket space, the amount of force placed on the teeth could be eight times less on the single bracket patients. This less force reduces undermining resorption and discomfort to the patient. The other advantages include: this archwire is more simple to engage and ligate; and/or a larger archwire could be placed with no more discomfort to the patient.

· WHAT ABOUT TORQUE?

· This increased space also allows for additional torsion control because a larger rectangular archwire can be engaged with no more force. The flexibility allows for fewer archwire changes – getting into finishing archwires sooner. Torsion allows earlier placement of rectangular archwires for faster torque control.

· Advantages of Interbracket Space:
(1) Simpler ligation
(2) Less patient discomfort
(3) Larger archwire early in treatment
(4) Early torque control when needed

· This additional space gives the archwire more resiliency and flexibility and will deliver a lighter force. When activated, the archwire is “alive.” There is less force applied to the teeth with the initial archwire due to the increased flexibility of the archwire allowed by the interbracket space. Energy is stored in this bent archwire and dispersed gradually over a longer period of time. Patient discomfort is then reduced.

· INTRA-BRACKET SPACE

· A.Inciso-gingival dimension:

· Another issue to discuss is “intra” bracket space. This is the space between the bracket slot and the engaged archwire. In a round archwire, the dimension of the wire will have an effect on the “friction” created while sliding through the slot. The smaller the wire, the less friction will be present: therefore, the more tooth movement will take place.

· It is well known that for every .001 inch of space, 5degrees of torque is lost when using a rectangular archwire. This is assuming that the quality of the bracket and archwire manufactured is of high quality. When the objective is to control the torque of the teeth, then a greater amount of “friction” is required. This is accomplished by filling up the slot with a larger rectangular archwire. This prescription gives just the right amount of freedom.

· B. Mesio- distal dimension:

· Some believe that a wider bracket is needed to control root angulation. In the Alexander Discipline this is not necessarily. Observe the panoramic radiographs in any of our finished cases in the lower anterior area and the only poor angulations you will find is the result of poor bracket placement!

· Mechanics

· The philosophy of AD is “control” … when needed. Do we need less friction or more friction? We can choose to have less friction or more friction not only in the archwire selected but within the arch itself. By choosing the type of ligation, friction can be controlled within the same archwire. How is this accomplished? When the archwire is engaged into the bracket slot, the forces then come alive and begin to move the teeth. Because of the flexibility of the archwire (new space age materials and increased interbracket spaces), the key is to “let it cook.” This has been one of our principles for many years! This is especially true in the maxillary archwire. The size of the archwire being placed into the bracket slot is the key to the amount of freedom and/or control. NiTi .014 or .016 wires are common initial archwires.

· The design of the ligation can influence the amount of friction on the archwire. The figure 8 ligation tie can reduce the friction. Steel ligation has less friction than elastomer rings.

· In the mandibular arch, a rectangular archwire will give a controlled, limited amount of tooth movement. This is because in most nonextraction cases the goal is to control the incisor torque as soon as possible. A flexible rectangular archwire is then often the wire of choice … CuNiTi or DRect.

· Curve of Spee

· When placing reverse curve into the mandibular archwire, the wire needs to be able to “slide” through the bracket as the teeth are leveled. Twin brackets will bind the wire much more than a single bracket because of the increased mesio-distal distance of these brackets. A simple test can demonstrate this fact. Compare how a typodont tooth will slide on an archwire using a twin bracket versus a single bracket. Add curve into the wire and the effect is even greater. The single bracket will slide much easier.

· Archwire Sequences / Retainer Effect

· The goal of sequencing archwires is to “get into the finishing archwire quickly, and let it cook.” (Principle # 13) This is accomplished within the first six months in most cases. As a result, the final archwire moves the teeth into their ideal positions, and then a “retainer effect” takes place. The archwire holds the teeth in their final positions for the remainder of treatment. As a result, after appliances are removed, the retainer is worn at night only. This can only have a positive effect on long term stability.

· Send in any questions you may have about The Alexander Discipline to Becky Davis