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P Lionel Sadowsky

Publications and source records attributed to P Lionel Sadowsky.

3 recordsLinked to original sources

An evaluation of the use of digital study models in orthodontic diagnosis and treatment planning.

The purpose of the present study was to determine the diagnostic and treatment planning value of digital models when compared with plaster study casts. In addition, the level of orthodontic experience of the examiner was assessed to determine whether this would have an influence on the decision-making process. Thirty randomly selected orthodontic patients from the Department of Orthodontics at the University of Alabama were selected for the study. From the 30 record sets, seven were selected attempting to mirror cases required for presentation to the American Board of Orthodontics. The seven evaluators were divided into two groups on the basis of their level of orthodontic experience. Initially, each evaluator assessed each patient record. Each evaluator was given a standardized questionnaire which recorded the evaluator's diagnosis based on use of the digital study models (T1). Regardless of whether the evaluator requested a review of the plaster study casts, the evaluator was given the plaster study casts. The evaluator then, using the plaster casts, filled out another identical questionnaire (T2). A chi-square test was used to determine any group differences in the frequency of changed diagnostic characteristics, treatment mechanical procedures, or proposed treatment plans after evaluating plaster study models. The statistical significance selected was P = .05 level of significance. The results showed that 12.8% of diagnostic characteristics, 12% of treatment mechanic procedures, and 6% of proposed treatment plans changed after T2. The results of the present study indicate that in the vast majority of situations digital models can be successfully used for orthodontic records.

Calcium Sulfate↗

Evaluation of the debonding characteristics of 2 ceramic brackets: an in vitro study.

The objectives of this study were to evaluate and compare the shear bond strengths and bond failure locations of 2 currently available orthodontic ceramic brackets. Forty polycrystalline ceramic brackets (Clarity, 3M Unitek, Monrovia, Calif) and 40 monocrystalline ceramic brackets (Inspire, Ormco, Orange, Calif) were bonded to 80 extracted premolars with the same bonding system. All bonded specimens were placed in distilled water for 42 hours at 37 degrees C followed by thermal cycling for 700 complete cycles. Forty ceramic brackets, 20 of each type, were tested on a universal testing machine to determine the shear force levels required to debond them. Forty ceramic brackets were removed with the debonding pliers recommended by the manufacturers. All teeth were examined under an optical microscope, and the adhesive remnant index was used to assess the bond failure locations. The mean shear bond strength of the Clarity brackets was 21.67 +/- 5.19 MPa, and the mean shear bond strength of the Inspire brackets was 20.32 +/- 8 MPa. The mean shear bond strengths of both brackets were higher than those considered clinically optimal. Most of the brackets (85% of Clarity and 75% of Inspire) tested on the machine failed at the bracket-adhesive interface. One premolar bonded with an Inspire bracket had enamel fracture upon debonding. Most of the brackets (90% of Clarity and 95% of Inspire) debonded with pliers failed at the bracket-adhesive interface. No enamel damage was evident in any specimen when the brackets were removed with the appropriate pliers. The results indicate that the safest way to remove ceramic brackets with respect to reducing the chance of enamel damage is to use the debonding technique specifically designed for each.

Bicuspid↗