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Objective: To obtain reference values for tip, torque and in-out from digital models of Italian and Mozambican subjects in ideal occlusion using a repeatable and validated method and to compare these measurements with previously reported values. Material and Methods: Dental parameters were acquired from digital models of each subject, categorized to one of two groups: Italians (23 males, 27 females; mean age 28.3 years, ±5.7 years) and Mozambicans (14 males, 15 females; mean age, 23.4 years, ±5.9), using VAM software. All subjects had ideal occlusion, permanent dentition and no previous orthodontic treatment, fillings or prostheses. After normality of data was assumed (p

Summary Objective To accurately describe compliance in headgear wearing time by using a temperature- and force-sensitive device over an 8 month period of use in a prospective clinical manner. Materials and methods Twenty children with Class II malocclusion aged 8–12 years were randomly selected for treatment with cervical headgear. The headgears were equipped with an electronic module, which measured temperature and force, and patients were instructed to wear the headgear 12 hours daily. The recorded values were analysed to determine the number of days the headgear was used, the number of hours per day it was worn, and the percentage of compliance (100 per cent corresponding to 12 hours daily). Results The average treatment period was 8.4 months with 5.8 months of effective use. When effectively used, headgear was worn 8.7 hours a day (compliance of 73 per cent). Including days where it was not worn, compliance was 6.4 hours (54 per cent). The appliance was used on average 0.5 hours during the day (8 am–8 pm) and 5.9 hours during the night (8 pm–8 am). Very low compliance was recorded during July and August. Conclusion The average compliance with cervical headgear use was 54 per cent of the 12 hour prescription. The headgear was effectively used only 5.8 months over the study period, with roughly 30 per cent of no use. Headgear was used almost exclusively during evening and night-time. During the summer period, compliance was particularly poor.

Objective: To analyze variations in palatal morphology in subjects presenting unilaterally impacted maxillary permanent central incisors compared with a control group of subjects without eruption anomalies using a three-dimensional (3D) analysis. Materials and Methods: Twenty-six white subjects (10 girls and 16 boys; mean age 9.5 ± 1.5 years) with unilaterally impacted maxillary permanent central incisors (impacted incisor group [IIG]) were compared with a control group (CG) of 26 subjects (14 girls and 12 boys, mean age 8.7 ± 1.6 years) presenting no eruption disorders. For each subject, dental casts were taken and the upper arch was scanned using a 3D laser scanner. To study the entirety of the shape of the palate in any point of the surface, 3D geometric morphometrics was applied. Results: Subjects with impacted maxillary incisors showed skeletal adaptations of the maxilla. In the IIG, both the superior palatal region and lateral palatal surface showed significantly different morphology when compared with CG, with a narrower and higher palatal vault. Conclusion: The absence of maxillary central incisors over the physiological age of eruption influenced the development of the palatal morphology compared with subjects without eruption anomalies.

Introduction The aims of this study were to evaluate the differences between 2 regions of maxillary voxel-based registration and to test the reproducibility of the registration. Methods Three-dimensional models were built for before-treatment (T1) and after-treatment (T2) based on cone-beam computed tomography images from 16 growing subjects. Landmarks were labeled in all T2 models of the maxilla, and voxel-based registrations were performed independently by 2 observers at 2 times using 2 reference regions. The first region, the maxillary region, included the maxillary bone clipped inferiorly at the dentoalveolar processes, superiorly at the plane passing through the right and left orbitale points, laterally at the zygomatic processes through the orbitale point, and posteriorly at a plane passing through the distal surface of the second molars. In the second region, the palate and infrazygomatic region had different posterior and anterior limits (at the plane passing through the distal aspects of the first molars and the canines, respectively). The differences between the registration regions were measured by comparing the distances between corresponding landmarks in the T2 registered models and comparing the corresponding x, y, and z coordinates from corresponding landmarks. Statistical analysis of the differences between the T2 surface models was performed by evaluating the means and standard deviations of the distances between landmarks and by testing the agreement between coordinates from corresponding landmarks (intraclass correlation coefficient and Bland-Altman method). Results The means of the differences between landmarks from the palate and infrazygomatic region to the maxillary region 3-dimensional surface models at T2 for all regions of reference, times of registrations, and observer combinations were smaller than 0.5 mm. The intraclass correlation coefficient and the Bland-Altman plots indicated adequate concordance. Conclusions The 2 regions of regional maxillary registration showed similar results and adequate intraobserver and interobserver reproducibility values.

Aim: To evaluate maxillary and mandibular dental arch changes induced by a passive self-ligating system by analysing digital dental casts. Subjects and methods: A sample of 25 growing patients (16 females and 9 males, mean age 12.8 years) treated with passive self-ligating brackets was compared to a sample of 25 untreated controls (15 females and 10 males, mean age 13.4 years). Sixty three-dimensional points were digitised on the maxillary and mandibular pre- and post-treatment virtual models to evaluate differences in the transverse and antero-posterior arch dimensions and in the torque values of representative anterior and posterior teeth. Statistical comparisons were performed with independent sample t -tests with Holm-Bonferroni correction for multiple tests. Results: The greatest increments in arch widths were found at the maxillary and mandibular premolar level (ranging from 2.0 to 2.2mm) and they were associated with significant increases in maxillary and mandibular arch perimeters (2.3 and 2.5mm, respectively), and in buccal crown torque of the upper premolars (with adequate torque control of all other teeth). Conclusions: The passive self-ligating system produced a modest but statistically significant widening of both maxillary and mandibular dental arches that were associated with significant net gains in maxillary and mandibular arch perimeters.

OBJECTIVE: To evaluate treatment and posttreatment dentoskeletal effects induced by the Forsus device (FRD) in growing patients with Class II malocclusion in a retrospective controlled clinical study. MATERIALS AND METHODS: Thirty-six Class II patients (mean [SD] age 12.3 [1.2] years) were treated consecutively with the FRD protocol and compared with a sample of 20 subjects with untreated Class II malocclusion (mean [SD] age 12.2 [0.9] years). Lateral cephalograms were taken at the beginning of treatment, at the end of comprehensive treatment (after 2.3 ± 0.4 years), and at a postretention period (after 2.3 ± 1.1 years from the end of comprehensive treatment). Statistical comparisons were carried out with the unpaired t-test and Benjamini-Hochberg correction (P < .05). RESULTS: After comprehensive treatment, the FRD sample showed a significant restriction of the sagittal maxillary growth together with a significant correction in overjet, overbite, and molar relationship. During the overall observation interval, the FRD group exhibited no significant sagittal or vertical skeletal changes, while significant improvements were recorded in overjet (−3.8 mm), overbite (−1.5 mm), and molar relationship (+3.7 mm). CONCLUSION: The FRD protocol was effective in correcting Class II malocclusion mainly at the dentoalveolar level when evaluated 2 years after the end of comprehensive treatment.

Background Continuous physiologic eruption of teeth may become a main aesthetic issue for implants inserted in the maxillary anterior region. Purpose To study maxillary tooth vertical changes during a 10 years period by 3-dimensional superimposition of digital dental casts. Material and methods Alginate impressions were taken at both baseline and at the 10-year follow-up in a sample of 24 adult Swedish women (average age of 48 years at T0). The upper arch plaster casts were digitized with a 3-dimensional scanner and then superimposed on the palate and the palatal rugae. Occlusal and gingival anatomic structures were digitized for each upper tooth from first molar to first molar. The vertical changes of these structures gave an indication of tooth extrusion and apical or coronal displacement of the gingival margin. Results A trend was found for eruption in the anterior region (+0.3 mm on average) while a slight extrusion if not any was found in the first molars and premolars area. Vertical displacement of the gingival margin showed also a positive trend from first molars to incisors. Negative average values, corresponding clinically to gingival recession, were found on first molars (−0.36 mm) and premolars (−0.15 mm), while no displacement was detected in the anteriors. Clinical crown lengths increased in all teeth and it is mainly due to gingival recession for first molars and premolars, while for the incisors the eruption is coupled to a slight equivalent gingival coronal migration. Conclusions During a 10-year period, continuous eruption takes place in female adult subjects, especially in the upper incisors area while gingival recession occurred in first molars and premolars area leading to crown length elongation. Implant placement in the anterior area of the maxilla may have an aesthetic impact even in mature adults due to the continuous eruption of the adjacent teeth.

Upper molar distalization supported by miniscrews has become increasingly popular in the last years. A detailed clinical and lab procedure for the realization of a distalization appliance (fast back or distal jet) connected to miniscrews inserted in the anterior region of the palate is presented. A case report illustrates the use of a fast back appliance supported by miniscrews to correct the mesial shift of the molars and of the premolars as a consequence of an early loss of the maxillary deciduous canines.

The objective of this study is to evaluate the effect of timing on Mandibular Anterior Repositioning Appliance (MARA) and fixed appliance treatment of Class II malocclusion in a prospective clinical trial. The treated sample consisted of 51 consecutively treated patients at prepubertal ( n = 21), pubertal ( n = 15), and postpubertal ( n = 15) stages of development. Control groups for the three treated groups were generated from growth data of untreated Class II subjects. Lateral cephalograms were digitized and superimposed via cephalometric software at T1 (pre-treatment) and T2 (after comprehensive treatment). The T1–T2 changes in the treated groups were compared to those in their corresponding control groups with Mann–Whitney tests with Bonferroni correction. Mandibular elongation was greater at the pubertal stage (Co–Gn +2.6 mm, with respect to controls). Headgear effect on the maxilla was greater in the pre-peak sample (Co–A −1.9 mm, with respect to controls). Dentoalveolar compensations (proclination of lower incisors, extrusion and mesialization of lower molars, and reduction in the overbite) were significant in the pre-peak and post-peak groups. Optimal timing for Class II treatment with MARA appliance is at the pubertal growth spurt, with enhanced mandibular skeletal changes and minimal dentoalveolar compensations.

Objective: To evaluate morphologic characteristics of occlusion (contact points, contact areas, and frequency of contact) in clinically successful patients 1 year after orthodontic and surgical-orthodontic therapy followed by passive retention. Materials and Methods: Twenty-two orthodontic and 18 surgical-orthodontic patients were analyzed. All patients were treated with standard edgewise technique by the same orthodontist. Contact points and areas were evaluated using a new method of digital image analysis of occlusal impressions. Polivinylsyloxan impressions were taken, scanned, and turned into gray-scale images. The physic relationship of light absorbance through the polivinylsyloxan for known thickness was calculated to determine contact areas (less than 50 μm of thickness) and near contact areas (less than 350 μm of thickness). Results: The contact area was significantly larger in the orthodontic than in the surgical-orthodontic patients (Student's t-test, P < .05). The surgical-orthodontic group had significantly fewer contact points than the orthodontic group only at 150 μm of thickness. In both groups of patients, the first molar had the largest contact surface. Occlusal support was distributed mainly in the posterior regions with an important role involving the first molars. Conclusion: Surgical-orthodontic patients appear to have smaller contact surfaces and fewer contact points than orthodontic patients do. However, there were no differences in the number of teeth in contact with opposing teeth.

Summary Objectives: To compare the dental ef fects produced by a bonded versus a banded expander combined with facial mask (FM) in patients with Class III malocclusion by means of digital dental casts. Materials and methods: Two groups of patients with Class III malocclusion and maxillary transverse deficiency in the deciduous or early mixed dentition were selected. The first group consisted of 25 subjects (12 females; 13 males) with a mean age of 7.4 years (SD 1.2 years) treated with a bonded expander and FM. The second group consisted of 25 subjects (13 females; 12 males) with a mean age of 8.1 years (SD 1.3 years) treated with a banded expander and FM. For each subject of the two groups, initial (pre-treatment, T1) and final (post-treatment, T2) dental casts were taken and scanned. Maxillary digital models of T1 and T2 were superimposed on the palatal rugae in order to analyse the maxillary anchorage loss. Significant between-group differences were tested with independent sample t-test (P

Objective: To assess maxilla and mandibular arch widths' response to Haas-type rapid maxillary expansion (RME) anchored to deciduous vs permanent molars on children with unilateral posterior crossbite. Materials and Methods: Seventy patients with unilateral posterior crossbite recruited at the Universities of Genova, Siena, and Insubria (Varese) were randomly located into GrE (RME on second deciduous molars) or Gr6 (RME on first permanent molars) and compared. Results: Upper intermolar distance and permanent molar angulation increased significantly in Gr6 vs GrE at T1. Upper intercanine distance increased significantly in GrE vs Gr6 at T1 and T2. GrE showed significant increases for upper intermolar and upper intercanine widths. Gr6 showed statistically significant increases for upper intermolar widths, for upper and lower intercanine widths, and for increases of angulation of upper and lower permanent molars. Conclusions: GrE showed reduced molar angulation increases at T1 and reduced molar angulation decreases at T2 when compared with Gr6. At T2, the net increase of the upper intercanine distance in GrE was still significant compared with Gr6, indicating a more stable expansion in the anterior area.

Summary Objective: To compare the anatomical characteristics of the maxillary arch, identified as palatal surface area and volume, between mouth-breathing and nose-breathing subjects using a threedimensional (3D) analysis of digital dental casts. Methods: Twenty -one Caucasian subjects (14 females and 7 males) with a mean age of 8.5 years [standard deviation (SD) 1.6 years] were selected according to the following criteria: mouth-breathing pattern due to allergic rhinitis, early mixed dentition, skeletal Class I relationship, and pre-pubertal stage of cervical vertebral maturation. This study group (SG) was compared with a control group (CG) of 17 nose-breathing subjects (9 females and 8 males, mean age: 8.5 years; SD: 1.7 years). For each subject, initial dental casts were taken and the upper arch was scanned using a 3D laser scanner. On each digital model, 3D measurements were performed to analyse maxillary arch morphology. Between-group differences were tested with the independent sample Student’s t-test (P

Background: This study tested the validity of, and describes, a novel method of constructing an average morphology of the dental arch. Methods: Upper dental arches of adult patients with a sound full permanent dentition were selected for the study. Laser-scanned images of the dental casts were obtained with an optical laser scanning device. The scanned images were analyzed using 3-dimensional graphic visualization and quantification software. Seventy-nine landmarks were identified on each dental arch on the basis of a protocol previously validated for dental analysis. An average dental arch (ADA) shell was then created and analyzed. Linear measures (crown height and mesiodistal width, intermolar and intercanine distances) and angular measures (inclination of the tooth on a reference plane), derived from the created ADA, were compared with the traditional average of measures, derived from single models, using 1-sample Student’s t test (P < 0.05). After validation, the ADA was used as a template for comparison with other dental arches presenting some form of malocclusion. Results: A total of 24 upper dental arches of adult patients with a sound full permanent dentition (mean [SD] age 28.8 [5.6] years) were selected for the study. The differences between the upper ADA and the average of single models were small (

OBJECTIVE: To evaluate the treatment and posttreatment dentoskeletal effects induced by the Mandibular Advancement Repositioning Appliance (MARA) in the treatment of Class II malocclusion. MATERIALS AND METHODS: The treated sample consisted of 23 consecutively treated patients at prepubertal or pubertal stages, as assessed by the cervical vertebral maturation method. A control group of untreated Class II subjects was generated from published normative growth data. Lateral cephalograms were digitized and superimposed via cephalometric software at three different times: T1, pretreatment; T2, post-MARA treatment; and T3, at least 1 year after T2. The T1–T2, T2–T3, and T1–T3 changes in the treated group were compared to those in the control group with independent-sample Student's t-tests. RESULTS: Skeletal and dentoalveolar effects of MARA were assessed after the active phase of the treatment (T1–T2). Mandibular elongation in length (Co-Gn, +2.2 mm) was evident together with lower incisor proclination (IMPA, +5.8 mm). A relapse tendency for IMPA was noticed after removing the appliance (IMPA, −2.1° during T2–T3). Significant skeletal effects (Co-Gn, +2.0 mm) and headgear effects on the maxilla (SNA, −1.2°) were significant in the long term (T1–T3). CONCLUSIONS: The MARA appliance provides an effective correction of Class II malocclusion, which is maintained at a posttreatment observation with a moderate skeletal effect.

Background The purpose of this controlled study was to investigate indirect effects on mandibular arch dimensions, 1 year after rapid palatal expansion (RPE) therapy. Methods Thirty-three patients in mixed dentition (mean age 8.8 years) showing unilateral posterior crossbite and maxillary deficiency were treated with a RPE (Haas type) cemented on the first permanent molars. Treatment protocol consisted of two turns per day until slight overcorrection of the molar transverse relationship occurred. The Haas expander was kept on the teeth as a passive retainer for an average of 6 months. Study models were taken prior (T1) and 15 months on average (T2) after expansion. A control group of 15 untreated subjects with maxillary deficiency (mean age 8.3 years) was also recorded with a 12-month interval. Stone casts were digitized with a 3D scanner (3Shape, DK). Results In the treated group, both mandibular intermolar distance (+1.9 mm) and mandibular molar angulation (+9°) increased. Mandibular incisor angulation showed an increase of 1.9°. There was little effect on intercanine distance and canine angulation. Controls showed a reduction in transverse arch dimension and a decrease in molar and canine angulation values. Conclusions RPE protocol has indirect widening effects on the mandibular incisors and first molars.

In this article, we report the successful use of miniscrews in the distalization of the lower dentition to correct an Angle class III malocclusion with lower anterior crowding in a dolichofacial adult patient. Conventional intraoral and extraoral appliances have many disadvantages, including the need for patient cooperation, potential for anchorage loss, and vertical extrusion of upper molars and lower incisors. Extrusion should be prevented or minimized when treating long-faced patients with reduced overbite. After third molar extractions, miniscrews were placed in the retromolar area. A sliding jig was applied to distalize the lower molars, while the anterior teeth were bonded and retracted secondarily to avoid round tripping. After 18 months of treatment, molar and canine class I relationship with normal overjet and overbite were achieved. In addition, there was an esthetic improvement in the profile with only a small increase of the lower anterior facial height. These results remained stable at a 12-month follow-up.