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Facial typing methods: A comparative study
Volume 100 Number 2
of these parameters would suggest an increased flexure of the posterior cranial base, (5) the association of molar relation, ramus position, and potion location correctly classified 92.14% of the total population, (6) observation of simple .correlation of coefficients between the seven Class III indicators demonstrated a high correlation of the proposed new variables (Xi. to Pt vertical, Xi to SNa vertical, and Xi-S-Na angle) with ramus position, and (7) multiple regression tests indicated that ramus position was the most consistent indicator of Class III malocclusion.
Load deformation tesI of metal brackets: A comparative study Luke K. Choi, Joseph M. Caruso, Daniel A. Flores, M. Toufic Jeiroudi, Jack L. Tomlinson, Garland E. Scott, Jr. Loma Linda, Calif.: Loma Linda University, 1990
The purpose of this study was to determine the effect material and design (slot torque degree and wing type) had on the force and stress to permanently deform metal brackets. Fourteen different types of metal brackets were tested and categorized into three categories. The three categories were raw material composition, slot torque degree, and wing type. There were five types of raw material (310SS, 316L, 303SE, 303S, and 17-4PH), three types of slot torque degree (0 °, 7 °, and 12°), and four types of wing design (mini twin, single, regular twin, and modified twin). All brackets were tested with the arch wire torque test developed by Flores. An analysis of variance (ANOVA) and Student's t test showed that raw material, wing type, and slot torque degree had a significant effect on the force and stress to permanently deform metal brackets. Of the three variables, raw material had the greatest effect on the force to permanently deform metal brackets. Results showed that 17-4PH and 303S had higher yield strengths, and regular twin had higher resistance to deformation. Also, as slot torque increased, brackets deformed with less force. A positive correlation between the micro hardness and the stress to deform metal brackets confirmed that brackets with the greatest stress to permanently deform were made of steels with the greatest hardness.
R e v i e w s a n d abstracts
195
CO-CR comparison of untreated and treated CL II Div 1 Cases James W. Davis, James R. Wise, Cielan G. Ehrler, John K. Pearson Loma Linda, Calif.: Loma Linda University, 1990
The purpose of this retrospective study was to compare the CO-CR differences in pretreatment and posttreatment Class II, Division 1 patients. Similar sample groups were chosen from patients of the graduate orthodontic clinic at Loma Linda University School of Dentistry. Each patient's models were mounted on a Sam II articulator with a face-bow transfer and a centric relation check bite. The CO-CR discrepancies in the anterior-posterior, superior-inferior, and side-shift dimensions were determined with the Mandibular Position Indicator. With t test analyses, statistically significant differences were found between the pretreatment and posttreatment groups, with the posttreatment sample exhibiting a smaller CO-CR discrepancy than the pretreatment sample.
Facial typing methods: A comparative study James A. Grabow, M. Toufic Jeiroudi, Michael J. Fillman, Roland D. Waiters Loma Linda, Calif.: Loma Lhzda Universit). 1990
Facial typing methods are used to determine to which of three basic facial pattern categories an individual patient belongs. These three categories are mesofacial, brachyfacial, and dolichofacial. It is important to establish the correct facial type because the reaction to treatment mechanics and the stability of the denture is dependent on the analysis of the facial patterns. The purpose of this paper was to show a comparative study of facial typing classification method used on 100 patients (47 boys and girls). The eight different methods used were as follows: Bioprogressive, Ricketts, LLU1, LLU2, QuickCeph, Jarabak, Facial-Mandibular Index, and Steiner. The Biopro~gressive method served as the control. The Bioprogressive derivative methods (Ricketts, LLU1, LLU2, and QuickCeph) had approximately 93% agreement, whereas Steiner, Jarabak, and FacialMandibular Index had 75%, 62%, and 46% agreement, respectively.
of these parameters would suggest an increased flexure of the posterior cranial base, (5) the association of molar relation, ramus position, and potion location correctly classified 92.14% of the total population, (6) observation of simple .correlation of coefficients between the seven Class III indicators demonstrated a high correlation of the proposed new variables (Xi. to Pt vertical, Xi to SNa vertical, and Xi-S-Na angle) with ramus position, and (7) multiple regression tests indicated that ramus position was the most consistent indicator of Class III malocclusion.
Load deformation tesI of metal brackets: A comparative study Luke K. Choi, Joseph M. Caruso, Daniel A. Flores, M. Toufic Jeiroudi, Jack L. Tomlinson, Garland E. Scott, Jr. Loma Linda, Calif.: Loma Linda University, 1990
The purpose of this study was to determine the effect material and design (slot torque degree and wing type) had on the force and stress to permanently deform metal brackets. Fourteen different types of metal brackets were tested and categorized into three categories. The three categories were raw material composition, slot torque degree, and wing type. There were five types of raw material (310SS, 316L, 303SE, 303S, and 17-4PH), three types of slot torque degree (0 °, 7 °, and 12°), and four types of wing design (mini twin, single, regular twin, and modified twin). All brackets were tested with the arch wire torque test developed by Flores. An analysis of variance (ANOVA) and Student's t test showed that raw material, wing type, and slot torque degree had a significant effect on the force and stress to permanently deform metal brackets. Of the three variables, raw material had the greatest effect on the force to permanently deform metal brackets. Results showed that 17-4PH and 303S had higher yield strengths, and regular twin had higher resistance to deformation. Also, as slot torque increased, brackets deformed with less force. A positive correlation between the micro hardness and the stress to deform metal brackets confirmed that brackets with the greatest stress to permanently deform were made of steels with the greatest hardness.
R e v i e w s a n d abstracts
195
CO-CR comparison of untreated and treated CL II Div 1 Cases James W. Davis, James R. Wise, Cielan G. Ehrler, John K. Pearson Loma Linda, Calif.: Loma Linda University, 1990
The purpose of this retrospective study was to compare the CO-CR differences in pretreatment and posttreatment Class II, Division 1 patients. Similar sample groups were chosen from patients of the graduate orthodontic clinic at Loma Linda University School of Dentistry. Each patient's models were mounted on a Sam II articulator with a face-bow transfer and a centric relation check bite. The CO-CR discrepancies in the anterior-posterior, superior-inferior, and side-shift dimensions were determined with the Mandibular Position Indicator. With t test analyses, statistically significant differences were found between the pretreatment and posttreatment groups, with the posttreatment sample exhibiting a smaller CO-CR discrepancy than the pretreatment sample.
Facial typing methods: A comparative study James A. Grabow, M. Toufic Jeiroudi, Michael J. Fillman, Roland D. Waiters Loma Linda, Calif.: Loma Lhzda Universit). 1990
Facial typing methods are used to determine to which of three basic facial pattern categories an individual patient belongs. These three categories are mesofacial, brachyfacial, and dolichofacial. It is important to establish the correct facial type because the reaction to treatment mechanics and the stability of the denture is dependent on the analysis of the facial patterns. The purpose of this paper was to show a comparative study of facial typing classification method used on 100 patients (47 boys and girls). The eight different methods used were as follows: Bioprogressive, Ricketts, LLU1, LLU2, QuickCeph, Jarabak, Facial-Mandibular Index, and Steiner. The Biopro~gressive method served as the control. The Bioprogressive derivative methods (Ricketts, LLU1, LLU2, and QuickCeph) had approximately 93% agreement, whereas Steiner, Jarabak, and FacialMandibular Index had 75%, 62%, and 46% agreement, respectively.