Juan J. AlióI; Carmen IglesiasII; José Fernández-LlebrezIII
AbstractObjective: The aim of this study was to establish how long the leveling phase lasted with and without JAL 90458 in a sample of patients undergoing orthodontic treatment with braces.
Method: Sixty patients were chosen who had been diagnosed with similar types of malocclusion. The sample was divided into three groups, each with 20 patients. Experimental Group 1 (ExG 1) was treated with a specific technique of ligating the archwire to the bracket (Orthospeed System) and applying the product JAL 90458. Experimental Group 2 (ExG 2) was treated with a straight archwire technique and JAL 90458 and Experimental Group 3 (Control Group) with the same technique as ExG 2 but without JAL 90458.
Results: 98.4% of the patients in ExG 1 passed every phase of the treatment and only 49.1% of the patients in ExG 2 did, while in the control group it was 24.1%. The leveling phase lasted, on average, 90.5 days in ExG 1, 165 days in ExG 2 and 270 days in the control group.
Conclusion: Using JAL 90458 with the Orthospeed System technique has been proven to reduce treatment time in the leveling and aligning phase. Using JAL 90458 with a conventional technique also reduces treatment time in the leveling and aligning phase, but significantly less than with the Orthospeed System technique. The longest leveling and aligning phase was with a conventional technique without JAL 90458. Key words: Friction, JAL 90458, Archwires, Ligatures, Brackets.
IntroductionFriction always appears whenever two surfaces slide against each other. During orthodontic treatment these frictional forces are decisive in every phase because they hinder sliding and affect the length of treatment.1-6 The energy produced by friction between the archwire and the bracket directly affects the total effective or efficient force needed to move teeth to the desired position.7
Many studies have been done on how to reduce friction, many of those with different bracket designs, including self-ligating braces.8,9 There are other factors that can affect the level of friction, among them the different kinds of ligatures between the bracket and the archwire,10 surface texture (the stick-slip phenomenon),11,12 the friction coefficient,13 the angulation between the wire axis and the bracket slot,11,12 the degree of elastic and plastic deformation of the archwire, etc.14,15 Friction increases the force required to move a tooth, causing periodontal damage, brackets becoming dislodged and loss of anchorage.5,16-21In addition, the friction coefficient is greater in rectangular wires than in round wires and it increases with wire thickness.12 It also increases with the use of esthetic materials (ceramic brackets).22 Finally, some researchers think saliva acts as a lubricant and decreases rubbing, while others consider that it can actually be an adhesion factor and therefore hinder sliding.1, 20, 23
The development of new self-proclaimed low friction or zero friction materials and techniques which promise to reduce treatment length are based on changing the bracket design and the surface structure of the arch wire. This can be done with ion implantation,24-26 Poly (Chloro-P-Xylylene) coating, hot nitrogen diffusion,16 alumina crystalline, gas nitriding,26 carbon coating, and plasma26 and Teflon16 deposition. However, these changes in the arch wire structure could alter its fundamental properties, as in the case of nickel-titanium wire implanted with ions, which changes the elastic recovery of the wire. None of these methods has been useful in the clinic on a day-to-day basis.
There are a few studies with different techniques designed to reduce friction that have been carried out on complete arches in typodonts,27 and even fewer on patients with braces.28
Currently, a new compound is being studied called JAL 90458 (ORTHOSPEED®). Its colloid consistency as a gel coats surfaces that come into contact with it, neutralizing the forces of friction by acting as a buffer.29,30
The aim of this study was to establish how long the leveling phase lasted with and without JAL 90458 in a sample of patients undergoing orthodontic treatment with braces.
Material and Methodology
The sample was made up of 60 individuals using the following selection criteria.
- Between 14 and 16 years of age.
- Permanent teeth.
- No agenesia or impaction of teeth.
- Skeletal Class I malocclusion.
- Face types: mesodolycho-meso-mesobrachyfacial.
- Mandibular incisor between 0 and 4 mm from the A-Pog plane.
- Negative bone-dental discrepancy between -4 and -6 mm in the lower arch.
- No previous orthodontic treatment.
- Low CAOD index.
- No signs of gingivitis.
- Plaque index lower than 20%.
The 60 subjects were divided into 3 groups.
GROUP 1. Patients undergoing treatment with JAL 90458 with the Orthospeed System technique: Experimental Group 1 (ExG 1).
GROUP 2. Patients undergoing treatment with a straight archwire and JAL 90458: Experimental Group 2 (ExG 2).
GROUP 3. Patients undergoing treatment with a straight archwire without JAL 90458 (control group).
Characteristics of JAL 90458 treatment: Orthospeed System. (Experimental Group 1)
There are three different types of JAL 90458 depending on its density:
JAL 90458 1 (Low density. Maximum fluidity)
JAL 90458 2 (Medium density. Moderate fluidity)
JAL 90458 3 (High density. Minimal fluidity)
Phases of treatment with Orthospeed System:
The Orthospeed System technique calls for applying JAL 90458 in three stages. First, we apply JAL 90458 nº2 at the back of the bracket slot, then we coat the entire surface of the archwire that will be placed in the brackets with JAL 90458 nº3 and, finally, we apply JAL 90458 nº3 and then nº1 on the archwire-bracket before fixing the ligature. In each of the phases below the same application technique is followed.
PHASE I. Placement of Roth prescription synergy brackets with a 0.22-inch slot. Bands on the first upper and lower molars. Palatal bar and lingual arch. Placement of a 0.14 super elastic nickel titanium ovoid archwire with a low-friction elastic ligature (RMO) in the middle slot of the bracket.
PHASE II. (15 days) Application of JAL 90458. An elastic low-friction ligature is put in place occupying two bracket tie wings.
PHASE III. (15 days) Application of JAL 90458. Elastic low-friction ligature occupying the three bracket tie wings.
PHASE IV. (15 days) Application of JAL 90458. Placement of a 019 .0.25-inch super elastic nickel titanium ovoid archwire with an elastic low-friction ligature in the middle slot of the bracket.
PHASE V. (15 days) Application of JAL 90458. Placement of an elastic low-friction ligature occupying two bracket tie wings.
PHASE VI. (15 days) Application of JAL 90458. Elastic low-friction ligature occupying the three bracket tie wings.
PHASE VII. (15 days) Application of JAL 90458. Placement of a 019 0.25-inch steel archwire with a conventional ligature in the three slots of the bracket.
Phases of treatment with Orthospeed System:
We applied JAL 90458 in each of the phases in the same way as we did in the previous group.
PHASE I. Placement of Roth prescription synergy brackets with a 0.22-inch slot. Bands on the first upper and lower molars. Palatal bar and lingual arch. Placement of a 0.14 super elastic nickel titanium ovoid archwire with a normal ligature in the three bracket tie wings.
PHASE II. (15 days) Placement of a 0.16 super elastic nickel titanium ovoid archwire with an elastic low-friction ligature in the three bracket tie wings.
PHASE III. (15 days) Placement of a 0.18 super elastic nickel titanium ovoid archwire with an elastic low-friction ligature in the three bracket tie wings.
PHASE IV. (15 days) Placement of a 0.16 0.22 super elastic nickel titanium ovoid archwire with an elastic low-friction ligature in the three bracket tie wings.
PHASE V. (15 days) Placement of a 0.19.0.25 super elastic nickel titanium ovoid archwire with an elastic low-friction ligature in the three bracket tie wings.
PHASE VI. (15 days) Placement of a 0.19.0.22 steel ovoid archwire with a conventional ligature in the three bracket tie wings.
3. Treatment characteristics of the Control Group.
We carried out the same technique as described in Experimental Group 2 but without applying JAL 90458.
Each treatment group consisted of 20 patients, 10 men and 10 women. The assignation of each patient to a particular group was done randomly.
All of the patients agreed to take part in this study.
Patients who do not pass a phase.
A patient was considered not to have passed a phase when the clinical activity of the following step could not be taken, whether it be due to archwire deformation or to some or all of the teeth not being adequately leveled.
Those patients who could not pass to the next phase, independent of the treatment they were undergoing, followed the protocol described below.
Protocol for patients not able to move on to next phase.
When a patient could not move on to the next phase, a nitinol archwire with a cross section size immediately below the one being used was put into place. An appointment was then made for 15 days later. If the patient still was not ready to move on to the next phase, another slightly smaller archwire was put into place.
In summary, a patient who was not ready to move on to the next phase was put on a specific therapeutic protocol. This procedure had a minimum 15-day duration and an indefinite maximum duration.
The patients were seen in three different clinics. None of the clinics knew a priori which group the patients belonged to. The clinic decided if the patient could pass from one phase to the next following the criteria listed below.
- The archwire showed no permanent deformations upon its removal.
- The archwire could be ligated or changed without producing forces greater than 100mg. on each tooth.
- No signs of gingivitis.
The treatment was considered to be complete when the clinic could put into place a 0.19.0.25-inch steel archwire ligating it passively in the three slots of the bracket.
III. Parameters to be determined.
I. Analysis within each group.
In each one of the three groups (Experimental 1, 2 and Control) the number of patients, both men and women, deemed ready to move on to the next phase was established.
II. Quantifying the treatment time.
In order to quantify the time within each group, each patient's time was added up and the arithmetic mean was found.
The data were analyzed using the statistical program SAS 9.1. The descriptive statistics of numeric independent variables for this test included the average and median of the time. The Kruskal-Wallis one-way analysis of variance by ranks for independent samples was applied. The analysis of variance (ANOVA) was used to assess the differences between groups.
In Table 1 we can see the number of patients that passed each of the different phases of the treatment. In ExG 1 all of the patients passed the different phases except for two men who did not pass phase III or IV. In ExG 2 the number of patients who passed all the phases was considerably less. It is worth pointing out that only eight men and seven women passed phase III and only six men and six women passed phase VI. In the control group the number of patients that passed all the phases was even less than in ExG 2, noting that only one man passed phase I and one women passed phase VI. The differences between the three groups were highly significant in all of the cases.
TABLE 1. Number of patients who passed the different phases of treatment.
Ex 1G: Experimental Group 1
Ex 2G: Experimental Group 2
Sig: Statistical significance.
Table 2 shows the number of days that each patient took to pass each of the different phases of the treatment. The minimum is 15 days per phase, so the total minimum is 90 days. If we take the group as a whole, the total minimum is 90x20=1800 days (arithmetic mean = 90 days/patient). When a patient did not pass a treatment phase he/she followed the corresponding protocol. The number of days spent in this protocol was recorded and added to the group total. Finally, the arithmetic mean was found.
We observed that the total number of days needed to complete all the phases in ExG 1 was 1830, which means that each patient took an average of 91.5 days. In ExG 2 the total number of days needed was 2380, with an average of 119 days per patient. Finally, in the control group the total number of days needed was 5400, with an average of 270 days per patient.
Significant differences were found in the three groups in all of the phases.
TABLE 2. Number of days taken to pass each of the phases of treatment for each group.
Ex 1G: Experimental Group 1
Ex 2G: Experimental Group 2
Sig: Statistical significance.
There are very few studies that analyze friction in patients undergoing treatment with orthodontic braces.18 Some studies apply in vitro models.27,31,32 This is due to the difficulty that arises in isolating the different variables which affect friction in patients undergoing treatment.6 For example, saliva is a variable that can reduce or increase friction according to various authors.1,20,23 JAL 90458 is a new coating product. In this respect, the concept of friction based on the archwire-bracket couple as the most important determining variable of friction14,33 is evolving due to the incorporation of new products which directly affect this couple.6 Along these lines, our clinical study isolates the variables that can affect friction by including a completely homogenous sample at the time of the initial diagnosis. Regarding the mechanics of the treatment, all of the patients were treated with the same kind of bracket (Synergy RMO) and the same kind of ligatures.
Non-conventional low-friction ligatures and conventional elastic ligatures were used in our study. Baccetti, et al.34 analyzed the friction that was produced by these two different types of ligatures and concluded that with a 0.14 archwire and pre-adjusted brackets, the friction produced by the non-conventional ligatures was significantly less throughout the leveling and aligning phase.10 We have used non-conventional low-friction ligatures (RMO) on the three groups and in all the phases, except for the last one when we used the 0.19. 025 steel archwire. The type of bracket used directly affects the friction produced. Many experimental studies have shown the efficacy of the reduction with self-ligating brackets.1,16,18,21,35,36 The bracket we used, having three tie wings, allows us to increase the chances of ligating the archwire by increasing or reducing the force generated.
Our study has analyzed the results in the leveling and aligning phase. Many authors agree that it is during this phase of orthodontic treatment when the greatest amount of friction is produced.37
JAL 90458 reduces friction and, therefore, it reduces the force applied on each tooth. This affects the absence of hyaline tissue produced when the applied force is of a certain magnitude.38,39 This is why the patients in our study could be seen every 15 days. The force applied on the teeth of the patients in Experimental Group 2, and especially in the control group, was much greater and probably produced hyaline tissue which slowed movement. With JAL 90458 we prevent this difficulty and this allows us to apply force at 15-day intervals. In Experimental Group 2 (ExG 2) we applied the product with a conventional straight archwire technique. The difference with respect to Experimental Group 1 is in the staggered progression of the archwires and the way in which all the tie wings were ligated in ExG 2. The statistically significant differences found between both groups lead us to believe that it is the staggered application of archwires which increases the applied force on the teeth (remember that in Experimental Group 1 a 0.14" archwire is not put into place until phase IV) and slows movement of the teeth. Likewise, the way in which the ligature is applied also affects the amount of force applied.
JAL 90458 applied with the Orthospeed System technique has proven to reduce treatment time in the leveling and aligning phase.
JAL 90458 applied with a conventional technique also reduces the duration of the leveling and aligning phase, but significantly less than with the Orthospeed System technique.
A conventional technique without JAL 90458 produced the longest treatment in the leveling and aligning phase.
IProfessor and Chair Orthodontic Department, Universidad Complutense de Madrid, Madrid, Spain.
IIProfessor of Master in Orthodontics, Universidad de Alcalá,, Madrid, Spain.
IIIMedical Director of Institute of Investigation in Orthodontics.