Finishing and detailing with a preadjusted appliance system. Humans; Male; Malocclusion, Angle Class II/therapy; Orthodontic Appliances*; Orthodontics. Am J Orthod Dentofacial Orthop. May;(5) A method of finishing the occlusion. Poling R. The preadjusted orthodontic appliance has improved. Author: McLaughlin RP, Journal: Journal of clinical orthodontics: JCO[/04].
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Modifications mostly involves alterations of a few degrees in tip and torque; but it is a known fact that expression of torque in particular is affected by many factors such as the slop between the archwire and the slot,  the method of ligation,  differences in the tolerance size of manufactured brackets and archwires,  initial inclination of the teeth,  and even variations in the shape of the labial surface of teeth. They claim that the thw palatal root torque in the upper incisors improves upon the under-torqued appearance produced by other prescriptions and the increased labial root torque in the lower incisor counteracts the forward tipping during leveling.
Several studies have shown the variations in torque values of teeth achieved following treatment with pre-adjusted edgewise appliances. Although many aspects of orthodontics are not easily orthodontlc, several valid and reliable indices have been developed to evaluate the alignment of the teeth before and after orthodontic treatment.
One of the most popular indices of dental alignment is the peer assessment rating PAR index. The advantage of using the PAR index is its ease of use, reliability, and validity. However, considering some of the inherent drawbacks in the PAR index such as it measures only one outcome of treatment, i. It is one of the most detailed indices in use. It consists of seven distinct model-scoring criteria and one panoramic radiographic criterion.
The American Board of Orthodontics Index ABOI is gaining increased recognition in the orthodontic profession as a valid measure of excellence in orthodontic finishing.
The aim of this study was to assess whether small changes in bracket prescription can lead to visually detectable differences in tooth positions as claimed by the bracket manufacturers. However, with little clinical evidence to show advantages of either of the bracket systems, orthodontists are forced to make clinical decisions with little scientific guidance. Confirmation of the bracket prescription used was obtained from the hospital notes, the departmental database, and by examination of clinical photographs taken during treatment.
The study received institutional research board approval to review patient records. Pre-treatment and post-treatment orthodontic records including panoramic and cephalometric radiographs as well as dental casts were obtained from the archives of Department of Orthodontics, Manipal College of Dental Sciences, Mangalore, India. These 40 cases were a subgroup selected from a larger sample that was collected without conscious bias as part of a concurrent outcomes study and fit the purposes of this study well.
It was an equal representation of different types of finished cases because it was stratified by sex, pretreatment Angle Class, and extraction pattern. Aged 20 years or under Treated with comprehensive orthodontic care using maxillary and mandibular fixed labial appliances Placement of a 0. Broken dental casts Mixed dentition state Incomplete records A non-extraction approach Extractions other than premolars A functional appliance treatment Use of headgear Surgical cases.
Using the pretreatment records, a discrepancy index DI was determined for each case by one examiner. Treatment time was calculated using the dates of initial bonding and removal of fixed appliances. Patients debonded prior to estimate time of treatment were not recorded. The gender and initial age of the patient were also recorded. P value less than or equal to 0.
The age, DI, and treatment time for the two groups are summarized in [Table – 1]. On correlation of the DI and the treatment time, r value of 0. Preadjustee adjusting for the covariates DI, age, gender, and treatment timewe found that the MBT bracket group had a lower score of 2. The alignment thd was further divided into four components: Maxillary anterior canine to canine alignment, mandibular anterior alignment, maxillary posterior alignment second premolar to second molarand mandibular posterior alignment.
When these four components were analyzed separately, mean maxillary and mandibular posterior alignment showed higher values; however, they are not statistically significant [Table – 3]. As the data distribution was skewed the Mann Whitney U test was done for interproximal contact and root angulations. The DI developed by the ABO  is ogthodontic objective method to describe the complexity of the treatment for a patient based on observations and measurements taken tge standard pretreatment orthodontic records.
Hence, DI can be used for prediction of treatment duration, although various other factors also contribute to the length of orthodontic treatment. Contrary to the findings of Schafer et al.
A possible explanation for this could be that this study wlth cases with bi-maxillary dento-alveolar protrusion treated with extraction of teeth, which is not considered in evaluating case complexity in DI in the other studies. Hence, not considering the axial inclinations of anterior teeth on basal bone as a parameter while evaluating the malocclusion could be considered a deficiency of the DI method in its current form.
The mean occlusal contact score obtained for MBT prescription is lower by 1.
Finishing and detailing with a preadjusted appliance system.
This could be attributed to the absence of overhanging palatal cusps sometimes seen in cases treated with other prescription; therefore, we can assume that the MBT prescription helps in achieving better intercuspation. However, only the buccolingual inclination preadjuzted occlusal contact categories were shown to be statistically significant, but with little or no clinical significance. The largest discrepancy in any one category was only 0.
When these four components were analyzed separately, maxillary and mandibular posterior alignment sub-categories scored higher in both Roth and MBT group; however, they were not statistically significant [Table – 3]. This may be attributed to the fact that second molar alignment was not given importance during treatment in both groups. As the data distribution was skewed, the Mann Whitney U test was done for interproximal contact and root angulations. The difference of 2.
A method of finishing the occlusion.
A difference of five points in the total ABO-OGS score and a difference of 6 months in treatment time would be considered clinically significant. Similarly, the increased palatal root torque of maxillary central and lateral incisors  present in MBT prescription does not have any apparent affect on clinical outcome.
This might be because of the possibility that the clinician manipulated the working arch-wire to introduce more torque into the cases treated with the Roth prescription.
Therefore, it can be stated that the overall clinical outcome will not be affected by the use of either one of the Roth or the MBT bracket prescriptions, and the quality of treatment result depends entirely on clinician judgment and experience.
No correlation was found between DI and treatment duration MBT prescription group had a statistically significant 2. However, it can be concluded that use of either one of the Roth and MBT bracket prescriptions have no impact to the overall clinical outcome and quality of finishkng entirely depends on clinician judgment and experience.
Although we used ABO-OGS to assess clinical outcome, which is a clear and objective method of measurement, other methods such as three dimensional laser scanning are more precise and may be able to detect differences between appliances. However, we would still state that orthodontics as a specialty always has a goal to produce the best esthetic result. Hence, a difference that is not appreciated by the human eye is of little importance. A further potential criticism of the study is that the patients were treated by different clinicians.
Operator variability might, therefore, have masked the differences in bracket prescription. However, it could be argued that the main aim of pre-adjusted edgewise appliances was to reduce the amount of wire bending required when treating patients and, therefore, promote more consistent treatment outcomes both within- and between-individual operators;  hence, it can be assumed that operator variability may not have had much influence the outcome of the study.
Torque expression in stainless steel orthodontic brackets. Back to cited text no. Gioka C, Eliades T. Materials-induced variation in the torque expression of preadjusted appliances. Am J Orthod Dentofacial Orthop ; Torque expression of self-ligating brackets.
An evaluation of slot size in orthodontic brackets-Are standards as expected? The variability of the curvature of the labial surface of the upper anterior teeth along the facial axis of the clinical crown. Arch Oral Biol ; Systemized orthodontic treatment mechanics. A scientific assessment of the straight-wire appliance. Am J Orthod ; Vardimon AD, Lambertz W. Statistical evaluation of torque angles in reference to straight-wire appliance SWA theories.
Ugur T, Yukay F. Normal faciolingual inclinations of tooth crowns compared with treatment groups of standard and pretorqued brackets. Comparison of Roth appliance and standard edgewise appliance treatment results.
The development of the PAR index: Eur J Orthod ; The ABO discrepancy index: A measure of case complexity. Objective grading system for dental casts and panoramic radiographs.
Treatment complexity index for assessing the relationship of treatment duration and outcomes in a graduate orthodontics clinic.
The relationship between the ABO discrepancy index and treatment duration in a graduate orthodontic clinic. Does bracket prescription have an effect on the subjective outcome of pre-adjusted edgewise treatment?