Rolf G Behrents

Saint Louis University, Сент-Луис, Michigan, United States

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Publications (52)66.73 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Long-term soft tissue response to extraction orthodontic treatment has been a subject of interest for years. The purposes of this study were to investigate long-term soft tissue profile changes in an extraction sample and to compare them with profile changes in an untreated sample. A premolar extraction-treated sample (n = 47) and an untreated control sample (n = 57) were studied. Descriptive statistics were collected, and individual t tests were used for comparison and contrast of the treated and untreated samples. We found that the untreated soft tissue profile changed in the downward and forward direction. The treated soft tissue profile change was similar, but with more of a forward component than in the untreated sample. Most noteworthy was the finding that the soft tissue profiles of both the untreated and the treated samples were similar at the end point. The following conclusions were derived from the study. (1) There was no substantive difference in the soft tissue profiles of the samples, but there were some differences in the directional changes between them. (2) The changes for the untreated sample were the greatest for the lips and the chin, with the change occurring in the downward and forward direction. (3) The soft tissue profiles of the extraction sample also had the greatest measurable changes in the lips and the chin, but the changes had more of a forward component than they did in the untreated sample. (4) Extraction treatment does not adversely impact soft tissue profile changes over time. Copyright © 2015 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.
    American journal of orthodontics and dentofacial orthopedics: official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics 05/2015; 147(5):596-603. DOI:10.1016/j.ajodo.2015.01.018 · 1.44 Impact Factor
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    ABSTRACT: Background The purpose of this study was to examine changes in mandibular arch dimensions of subjects submitted to either bonded or banded maxillary expansion. Methods The sample comprised of two groups, one with patients who underwent maxillary expansion with banded, Haas-type expanders, retrospectively selected (banded group), and the other patients carefully matched in sex, age, and malocclusion, prospectively observed with bonded, Hyrax-type expanders (bonded group). Each group was composed of 29 subjects evaluated at T1, before maxillary expansion, and T2, after expansion and stabilization. The mandibular arches were evaluated for changes in arch width, depth, and perimeter. Paired and independent Student's t tests were used to compare groups. Results Patients in the banded group experienced significantly more mandibular arch width expansion in the molar region. Both groups experienced a decrease in arch depth; however, the bonded group showed significantly greater loss. Conclusion Rapid maxillary expansion is an effective method for achieving a gain in arch width and space in the maxillary arch and, depending on the type of expander, banded or bonded, it produces a different response on an untreated mandibular arch.
    09/2014; DOI:10.1016/j.ejwf.2014.05.003
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    ABSTRACT: Introduction The purpose of this study was to evaluate the treatment effects of maxillary posterior tooth distalization performed by a modified palatal anchorage plate appliance with cephalograms derived from cone-beam computed tomography. Methods The sample consisted of 40 lateral cephalograms obtained from the cone-beam computed tomography images of 20 Class II patients (7 men, 13 women; average age, 22.9 years) who underwent bilateral distalization of their maxillary dentition. The lateral cephalograms were derived from the cone-beam computed tomography images taken immediately before placement of a modified palatal anchorage plate appliance and at the end of distalization. Paired t tests were used for comparisons of the changes. Results The distal movement of the maxillary first molar was 3.3 ± 1.8 mm, with distal tipping of 3.4° ± 5.8° and intrusion of 1.8 ± 1.4 mm. Moreover, the maxillary incisors moved 3.0 ± 2.7 mm lingually, with lingual tipping of 6.2° ± 7.6° and insignificant extrusion (1.1 mm; P = 0.06). The occlusal plane angle was increased significantly (P = 0.0001). Conclusions The maxillary first molar was distalized by 3.3 mm at the crown and 2.2 mm at root levels, with distal tipping of 3.4°. It is recommended that clinicians should consider using the modified palatal anchorage plate appliance in treatment planning for patients who require maxillary total arch distalization.
    American Journal of Orthodontics and Dentofacial Orthopedics 07/2014; 146(1):47–54. DOI:10.1016/j.ajodo.2014.03.023 · 1.44 Impact Factor
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    American Journal of Orthodontics and Dentofacial Orthopedics 06/2014; 145(6):711. DOI:10.1016/j.ajodo.2014.04.007 · 1.44 Impact Factor
  • American Journal of Orthodontics and Dentofacial Orthopedics 01/2014; 145(1):2-3. DOI:10.1016/j.ajodo.2013.11.009 · 1.44 Impact Factor
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    ABSTRACT: With the advent of cone beam computed tomography (CBCT), it is now possible to quantitatively evaluate the effects of rapid maxillary expansion (RME) on the entire maxillary complex in growing patients. The purpose of this study is to use three-dimensional images to evaluate the displacement that occurs at the circummaxillary sutures (frontonasal, zygomaticomaxillary, intermaxillary, midpalatal, and transpalatal sutures) following rapid maxillary expansion in growing children. The CBCT scans of 25 consecutively treated RME patients (10 male, 15 female) with mean age of 12.3 ± 2.6 years, were examined before expansion and immediately following the last activation of the expansion appliance. Statistically significant (P < 0.05) amounts of separation were found for the displacement of the bones of the frontonasal suture, the intermaxillary suture, the zygomaticomaxillary sutures, and the midpalatal suture. The change in angulation of the maxillary first molars due to RME was also statistically significant. There was no statistically significant displacement of the transpalatal suture. Rapid maxillary expansion results in significant displacement of the bones of circummaxillary sutures in growing children.
    01/2014; 19(1):26-35. DOI:10.1590/2176-9451.19.1.026-035.oar
  • American journal of orthodontics and dentofacial orthopedics: official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics 10/2013; 144(4):499-500. DOI:10.1016/j.ajodo.2013.08.009 · 1.44 Impact Factor
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    ABSTRACT: The purpose of this study was to determine whether Angle Class II subdivision malocclusions have skeletal or dental asymmetries between the Class II and Class I sides. A sample of 54 untreated Angle Class II subdivision patients with pretreatment photos and cone-beam computed tomography (CBCT) scans was used. The photos were used to identify the Class II subdivision malocclusion and to record the amount of crowding per quadrant. Landmarks were plotted on each CBCT volume so that direct 3-dimensional measurements could be made to compare the positions and dimensions of the skeletal and dental structures on the Class II side vs the Class I side. Significant differences were found for 2 skeletal measurements: the position of the maxilla relative to the cranial base, and the mandibular dimension from the mandibular foramen to the mental foramen. Statistically significant dental differences were found for the position of the mandibular first molars and canines in relation to the maxilla and the mandible. Statistically significant differences were found for the maxillary first molars and canines in relation to the mandible. There were significant skeletal and dental differences between the Class I and Class II sides. The dental asymmetries accounted for about two thirds of the total asymmetry.
    American journal of orthodontics and dentofacial orthopedics: official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics 07/2013; 144(1):57-66. DOI:10.1016/j.ajodo.2013.02.026 · 1.44 Impact Factor
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    ABSTRACT: INTRODUCTION: Sequential stages in the development of the hand, wrist, and cervical vertebrae commonly are used to assess maturation and predict the timing of the adolescent growth spurt. This approach is predicated on the idea that forecasts based on skeletal age must, of necessity, be superior to those based on chronologic age. This study was undertaken to test this reasonable, albeit largely unproved, assumption in a large, longitudinal sample. METHODS: Serial records of 100 children (50 girls, 50 boys) were chosen from the files of the Bolton-Brush Growth Study Center in Cleveland, Ohio. The 100 series were 6 to 11 years in length, a span that was designed to encompass the onset and the peak of the adolescent facial growth spurt in each subject. Five linear cephalometric measurements (S-Na, Na-Me, PNS-A, S-Go, Go-Pog) were summed to characterize general facial size; a sixth (Co-Gn) was used to assess mandibular length. In all, 864 cephalograms were traced and analyzed. For most years, chronologic age, height, and hand-wrist films were available, thereby permitting various alternative methods of maturational assessment and prediction to be tested. The hand-wrist and the cervical vertebrae films for each time point were staged. Yearly increments of growth for stature, face, and mandible were calculated and plotted against chronologic age. For each subject, the actual age at onset and peak for stature and facial and mandibular size served as the gold standards against which key ages inferred from other methods could be compared. RESULTS: On average, the onset of the pubertal growth spurts in height, facial size, and mandibular length occurred in girls at 9.3, 9.8, and 9.5 years, respectively. The difference in timing between height and facial size growth spurts was statistically significant. In boys, the onset for height, facial size, and mandibular length occurred more or less simultaneously at 11.9, 12.0, and 11.9 years, respectively. In girls, the peak of the growth spurt in height, facial size, and mandibular length occurred at 10.9, 11.5, and 11.5 years. Height peaked significantly earlier than both facial size and mandibular length. In boys, the peak in height occurred slightly (but statistically significantly) earlier than did the peaks in the face and mandible: 14.0, 14.4, and 14.3 years. Based on rankings, the hand-wrist stages provided the best indication (lowest root mean squared error) that maturation had advanced to the peak velocity stage. Chronologic age, however, was nearly as good, whereas the vertebral stages were consistently the worst. Errors from the use of statural onset to predict the peak of the pubertal growth spurt in height, facial size, and mandibular length were uniformly lower than for predictions based on the cervical vertebrae. Chronologic age, especially in boys, was a close second. CONCLUSIONS: The common assumption that onset and peak occur at ages 12 and 14 years in boys and 10 and 12 years in girls seems correct for boys, but it is 6 months to 1 year late for girls. As an index of maturation, hand-wrist skeletal ages appear to offer the best indication that peak growth velocity has been reached. Of the methods tested here for the prediction of the timing of peak velocity, statural onset had the lowest errors. Although mean chronologic ages were nearly as good, stature can be measured repeatedly and thus might lead to improved prediction of the timing of the adolescent growth spurt.
    American journal of orthodontics and dentofacial orthopedics: official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics 06/2013; 143(6):845-854. DOI:10.1016/j.ajodo.2013.01.019 · 1.44 Impact Factor
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    ABSTRACT: Abstract Objective: To describe maxillary growth and maturation during infancy and early childhood. Materials and Methods: Serial cephalograms (N  =  210) of 30 subjects (15 females and 15 males) from the Bolton-Brush Growth Study were analyzed. Each subject had a series of six consecutive cephalograms taken between birth and 5 years of age, as well as one adult cephalogram. Twelve maxillary measurements (eight linear and four angular) and seven landmarks were used to characterize maxillary growth. Maturation of the linear measures was described as a percentage of adult status. Results: Maxillary and anterior cranial base size increased in both sexes between 0.4 and 5 years of age. The linear anteroposterior (AP) measures (S-SE, SE-N, ANS-PNS) increased almost as much as the vertical measures (S-PNS, SE-PNS, N-A, N-ANS) over the first 5 years. After 5 years of age there was significantly more vertical than AP growth. The size and shape changes that occurred were greatest between 0.4 and 1 years; yearly velocities decelerated regularly thereafter. Overall linear growth changes that occurred between 0.5 and 5 years of age (a span of 4.5 years) were generally greater than the changes in maxillary growth that occurred between 5 and 16 years (a span of 11 years). The linear measures showed a gradient of maturation, with the AP measures being more mature than the vertical measures. Male maxillae were less mature than female maxillae at every age. Conclusions: The maxilla undergoes its greatest postnatal growth change during infancy and early childhood, when relative AP growth and maturation are emphasized.
    The Angle Orthodontist 11/2012; DOI:10.2319/071312-580.1 · 1.28 Impact Factor
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    ABSTRACT: Abstract Objective: To understand the relationships between facial divergence, vertical growth, and postretention mandibular crowding. Materials and Methods: Seventy-five white extraction patients were evaluated immediately posttreatment (15.4 years) and again 16.6 years later. Hyperdivergent subjects, subjects with open bite or severe deep bites were not evaluated. Changes in incisor irregularity and tooth-size arch-length discrepancies (TSALD) were evaluated and correlated with measures of divergence and skeletal growth. Results: Incisor irregularity increased 0.9 mm and TSALD increased 0.7 mm after treatment; 68% of the subjects had less than 3.5 mm incisor irregularity at postretention. Male patients showed significantly more growth than female patients did. Female patients, who were significantly more hyperdivergent than male patients, showed weak to moderately weak associations between posttreatment facial divergence and crowding. Female posttreatment changes in anterior face height, lower incisor eruption, and changes in arch depth were also related to crowding; male patients showed moderate relationships between posttreatment changes in arch width and crowding. Conclusions: Greater vertical growth, incisor eruption, and especially facial divergence are related to greater posttreatment mandibular crowding.
    The Angle Orthodontist 10/2012; 83(3). DOI:10.2319/061912-505.1 · 1.28 Impact Factor
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    ABSTRACT: OBJECTIVE: To evaluate immediate soft tissue changes following rapid maxillary expansion (RME) in growing patients, using cone beam computed tomography (CBCT). METHODS: Twenty-three consecutive patients (10 male, 13 female) treated by RME were selected. Patients were scanned using CBCT prior to placement of the rapid maxillary expander (T0), then immediately following full activation of the appliance (T1). Defined landmarks were then located on the pre- and post-treatment orientated images. Change in landmark position from pre- to post-treatment was then measured. In addition to landmarks, 10 direct measures were made to determine distance change without regard to direction to measure soft tissue change of the lips. RESULTS: Significant transverse expansion was measured on most soft tissue landmark locations. All the measures made showed significant change in the lip position with a lengthening of the vertical dimension of the upper lip, and a generalized decrease of anterior-posterior thickness of both the upper and lower lips. CONCLUSIONS: Significant changes in the soft tissue do occur with RME treatment. There is a transverse widening of the midface, and a thinning of the lips.
    10/2012; 17(5):157-164. DOI:10.1590/S2176-94512012000500022
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    ABSTRACT: The purpose of this study was to use cone-beam computed tomography to compare mandibular dimensions in subjects with asymmetric skeletal Class III malocclusion and those with normal occlusion. Cone-beam computed tomography scans of 38 subjects with normal occlusion and 28 patients with facial asymmetry were evaluated and digitized with Invivo software (Anatomage, San Jose, Calif). Three midsagittal and 13 right and left measurements were taken. The paired t test was used to compare the right and left sides in each group. The Mann-Whitney U test was used to compare the midsagittal variables and the differences between the 2 sides of the group with normal occlusion with those of asymmetry patients. The posterior part of the mandibular body showed significant differences between the deviated and nondeviated sides in asymmetric Class III patients. The difference of the asymmetry group was significantly greater than that of the normal occlusion group for the mediolateral ramal and the anteroposterior condylar inclinations (P = 0.007 and P = 0.019, respectively). The asymmetric skeletal Class III group showed significant differences in condylar height, ramus height, and posterior part of the mandibular body compared with the subjects with normal occlusion. These results might be useful for diagnosis and treatment planning of asymmetric Class III patients.
    American journal of orthodontics and dentofacial orthopedics: official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics 08/2012; 142(2):179-85. DOI:10.1016/j.ajodo.2012.03.024 · 1.44 Impact Factor
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    ABSTRACT: The purpose of this study was to assess differences in dentoalvolar cortical bone thickness between hyperdivergent and hypodivergent young adults. Pretreatment cone-beam computed tomography images of 57 patients, including 30 hypodivergent subjects (22 women, 8 men) and 27 hyperdivergent subjects (20 women, 7 men), were analyzed. The data were imported into imaging software (version 10.5; Dolphin Imaging Systems, Chatsworth, Calif); standardized orientations were used to measure buccal and lingual cortical bone thicknesses at 16 interradicular sites of the maxilla and the mandible. Total alveolar ridge thickness and medullary space thickness were measured at the same sites. T tests showed significant (P <0.05) group differences, with hypodivergent subjects having significantly thicker buccal cortices. The lingual cortex of the maxilla was also significantly thicker in the hypodivergent than in the hyperdivergent subjects. Alveolar ridge thickness was significantly greater at all sites of the hypodivergent mandible and at the anterior 2 sites of the hypodivergent maxilla. Medullary thickness was significantly greater only in the hypodivergent mandibles between the first molars and the second premolars, and between the first and second premolars. Buccal cortical bone was significantly thicker than lingual cortical bone in the mandible; lingual bone was significantly thicker in the maxilla. Cortical bone tends to be thicker in hypodivergent than in hyperdivergent subjects. This explains the concomitant differences in alveolar ridge thickness. Medullary space thickness is largely unaffected by facial divergence.
    American journal of orthodontics and dentofacial orthopedics: official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics 08/2012; 142(2):170-8. DOI:10.1016/j.ajodo.2012.03.021 · 1.44 Impact Factor
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    ABSTRACT: Abstract Objective: To determine whether dentoalveolar changes or vertical condylar growth is more closely related to the true forward rotation of the mandible during the transition between the late primary and early mixed dentition stages of development. Materials and Methods: The sample included 50 subjects (25 males and 25 females) with Class I (N  =  25) and Class II (N  =  25) molar relationships. They were selected based on the availability of lateral cephalograms at two developmental stages: T1: last film with complete primary dentition (5.8 ± 0.4 years) and T2: first film with permanent incisors and permanent molars fully erupted (8.0 ± 0.2 years). Seventeen landmarks were identified and 22 measurements were calculated. The mandibles at T1 and T2 were superimposed using natural reference structures in order to measure true mandibular rotation. Results: The mandible underwent -2.4° ± 2.6° of true rotation, 1.9° ± 2.4° of remodeling, and -0.6° ± 1.8° of apparent rotation. There were no significant sex or Class differences in true rotation, remodeling, and apparent rotation. There was a moderate correlation (r  =  0.76) between true rotation and remodeling and a moderately low correlation (r  =  0.40) between true rotation and apparent rotation. There was a weak correlation between true rotation and SNA (r  =  0.28). True rotation was most closely associated with the increases in U1/S-N (r  =  -0.34), increases in U1/PP (r  =  -0.36), and decreases in Id-Me (r  =  0.36). Conclusions: Independent of sex and Class, the true mandibular rotation that occurred between the late primary and early mixed dentition was mostly masked by angular remodeling, resulting in limited amounts of apparent rotation. True rotation was significantly related to anterior dentoalveolar changes but not to the vertical growth changes that occurred.
    The Angle Orthodontist 06/2012; DOI:10.2319/031312-220.1 · 1.28 Impact Factor
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    ABSTRACT: To experimentally study the effects of altering implant length, outer diameter, cortical bone thickness, and cortical bone density on the primary stability of orthodontic miniscrew implants (MSIs). Maximum insertion torque (IT) and pullout strength (POS) of 216 MSIs were measured in synthetic bone with different cortical densities (0.64 g/cc or 0.55 g/cc) and cortical thicknesses (1 mm or 2 mm). Three MSIs were evaluated: 6-mm long/1.75-mm outer diameter, 3-mm long/1.75-mm outer diameter, and 3-mm long/2.0-mm outer diameter. To test POS, a vertical force was applied at the rate of 5 mm/min until failure occurred. The 6-mm MSIs displayed significantly (P < .001) higher IT and POS than the 3-mm MSIs did. The 3-mm MSIs with 2.0-mm outer diameters showed significantly higher (P < .001) IT and POS than the 3-mm MSIs with 1.75-mm outer diameters. The IT and POS were significantly (P < .001) greater for the MSIs placed in thicker and denser cortical bone. Both outer diameter and length affect the stability of MSIs. Increases in cortical bone thickness and cortical bone density increase the primary stability of the MSIs.
    The Angle Orthodontist 12/2011; 82(4):603-10. DOI:10.2319/070111-427.1 · 1.28 Impact Factor
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    ABSTRACT: To characterize the mixed-longitudinal craniofacial growth of untreated, white, Class III subjects 6 to 16 years of age. Serial cephalograms of 19 females and 23 males with Class III malocclusion were evaluated at three time points (6-8, 10-12, and 14-16 years of age). A similar number of Class I controls were randomly selected and matched for age and sex. The cephalograms were traced and digitized, and 20 variables were evaluated. Growth patterns were quantified, and class and sex differences were evaluated using multi-level analyses. In comparison with Class I subjects, Class III subjects had significantly (P ≤ .05) larger mandibular plane angles, gonial angles, mandibular ramus heights, mandibular corpus lengths, and SNB angles, with differences that were maintained between 6 and 16 years of age. Maxillary lengths and ANB angles were significantly smaller and remained smaller in Class III subjects than in Class I subjects. Lower face height, maxillary-mandibular differential, and mandibular body length were also significantly larger and increased significantly more between 6 and 16 years of age in Class III subjects. The WITS appraisal was significantly smaller in Class III subjects and decreased significantly more over time. Most linear measures showed significant sex differences favoring males; the angular measures and anteroposterior (AP) maxillomandibular relationships showed no sex differences. The AP maxillomandibular relationship of Class III subjects worsens over time. AP discrepancies are primarily due to excessive mandibular growth, which produces a protrusive, hyperdivergent phenotype. The AP discrepancies of males are larger than those of females, with differences increasing over time.
    The Angle Orthodontist 03/2011; 81(2):211-6. DOI:10.2319/051010-252.1 · 1.28 Impact Factor
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    ABSTRACT: To assess the spatial changes in the relationship of the mandible to the maxilla with different extraction patterns and techniques when treated Class II patients are compared with untreated subjects. Pretreatment and posttreatment cephalometric radiographs of 125 Class II adolescent patients and 30 untreated Class II patients were traced. The treated patients were divided by technique and extraction pattern into four groups: preangulated appliance with four first premolar (4/4) extractions, preangulated appliance with maxillary first and mandibular second premolar (4/5) extractions, standard edgewise (Tweed-Merrifield technique) with four first premolar (4/4) extractions, and standard edgewise (Tweed-Merrifield technique) with maxillary first and mandibular second premolar (4/5) extractions. The mandibular displacement vector angle was determined by using two different superimposition methods: the superimposition on the cranial base and the superimposition on the maxillary base. The differences in the mean vector angles of mandibular displacement in the two superimposition methods were statistically compared. There was a significant difference between the vector angle of mandibular displacement in each treated group when the superimposition techniques (ie, cranial base and maxillary base) were compared. Significant differences between the standard edgewise treated group and the preangulated treated group were found using both superimposition methods. The standard edgewise appliance groups showed a more forward horizontal displacement of the mandible than the preangulated appliance groups. Within the standard edgewise sample, the patients with four first premolars extracted had a greater horizontal mandibular displacement than did the maxillary first, mandibular second premolar extraction sample.
    The Angle Orthodontist 02/2011; 81(4):584-91. DOI:10.2319/071610-405.1 · 1.28 Impact Factor
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    ABSTRACT: To characterize postorthodontic settling of the posterior occlusion of patients wearing Hawley retainers vs patients who initially wore Perfector retainers and then switched to Hawley retainers. This follow-up study was based on 40 patients (25 Perfector and 15 Hawley), who were part of a larger sample of 50 patients randomly assigned to wear either Hawley or Perfector retainers. The Perfector patients were given Hawley retainers 2 months after retainer delivery. Occlusal bite registrations were scanned and traced to quantify posterior areas of contact and near contact (ACNC). A seven-item questionnaire was used to assess the patient's perception of occlusion. Measurements were obtained at the on the day of retainer delivery, 2 months post delivery, 6 months post delivery, and 8 months post delivery. ACNC increased significantly (P < .05) during the first 6 months of retainer wear. The ACNC of the Hawley and Perfector/Hawley groups increased by 129% and 105%, respectively, over 8 months of retention. The greatest increases in ACNC occurred during the first 2 months. The ACNC further increased between 2 and 6 months in both groups. The Perfector/Hawley group also showed slight increases in ACNC between 6 and 8 months. Overall group differences were not statistically significant. The Perfector/Hawley group perceived greater improvements in occlusion than the Hawley group, but group differences after 8 months were small. Substantial amounts of settling occurred at decelerating rates during the first 6 months after retainer delivery. No significant differences in ACNC were found between the Hawley and Perfector/Hawley groups after 8 months of retainer wear.
    The Angle Orthodontist 09/2010; 80(5):853-60. DOI:10.2319/090109-496.1 · 1.28 Impact Factor
  • Yi-Ping Liu, Rolf G Behrents, Peter H Buschang
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    ABSTRACT: To describe the growth, maturation, and remodeling changes of the mandible during infancy and early childhood. Seven Bolton-Brush Growth Study longitudinal cephalograms (N = 336) of each of 24 females and 24 males, taken between birth and 5 years of age, as well as early adulthood, were traced and digitized. Five measurements and nine landmarks were used to characterize mandibular growth, remodeling, and degree of adult maturity. Overall, mandibular length showed the greatest growth changes, followed by ramus height and corpus length. Corpus length was the most mature of the three linear measures; ramus height was less mature than overall mandibular length. The greatest growth rates occurred between 0.4-1 year; yearly velocities decelerated thereafter. The ramus remodeled superiorly only slightly more than it remodeled posteriorly. Male mandibles were significantly (P < or = .05) larger, displayed greater growth rates, and were significantly less mature than female mandibles. There were no significant differences in mandibular growth or maturation between Class I and Class II patients. The mandible displays decelerating rates of growth and a maturity gradient during infancy and early childhood, with males showing more growth and being more mature than females.
    The Angle Orthodontist 01/2010; 80(1):97-105. DOI:10.2319/020309-67.1 · 1.28 Impact Factor

Publication Stats

496 Citations
66.73 Total Impact Points

Institutions

  • 2005–2015
    • Saint Louis University
      • Center for Advanced Dental Education "CADE"
      Сент-Луис, Michigan, United States
  • 2000–2006
    • Baylor College of Dentistry
      • Department of Orthodontics
      Dallas, Texas, United States
  • 1987–1996
    • University of Tennessee
      • Department of Orthodontics
      Knoxville, Tennessee, United States
    • University of Alabama at Birmingham
      • Division of Biomaterials
      Birmingham, Alabama, United States