Introduction: The purpose of this investigation was to evaluate craniofacial growth changes from late adolescence through late adulthood in participants from the University of Michigan Elementary and ...Secondary School Growth Study. Methods: This was a recall study with 39 subjects (19 male, 20 female). Their lateral cephalograms taken during late adolescence (T1; mean age, about 17 years), midadulthood (T2; mean age, about 47 years), and late adulthood (T3; mean age, about 57 years) were evaluated. To test for significant differences between times, sexes, and the sex and time interaction, repeated measures analysis of variance was used. For the comparisons of time (T1 vs T2, T2 vs T3), the nominal α level was set at 0.01. Results: Skeletal changes were significant only from late adolescence to midadulthood; soft-tissue changes were significant from late adolescence to midadulthood, and mid- to late adulthood. Changes in skeletal tissues consisted of increases in sella-nasion length, midfacial length, and lower anterior facial height. Sex differences were apparent in the mandible. The women had downward and backward mandibular rotation; the men, on the other hand, had more forward rotation of the mandible and increased chin prominence. Mandibular growth was greater in the men. Changes in the soft tissues were the most remarkable and included significant thinning and elongation of the upper lip. Significant changes in the nose took place, including drooping of the nasal tip and columella, the latter leading to more acute nasolabial angles. Conclusions: Our findings in this longitudinal study provide insights on several significant changes in the aging craniofacial complex.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Summary
Objective
To evaluate the role of treatment timing on long-term dentoskeletal effects of Class II treatment with removable functional appliances followed by full-fixed appliance therapy.
...Materials and methods
A group of 46 patients (23 females and 23 males) with Class II malocclusion treated consecutively with either Bionator or Activator, followed by fixed appliances was compared with a matched control group of 31 subjects (16 females and 15 males) with untreated Class II malocclusion. The treated sample was evaluated at T1, start of treatment (mean age: 9.9 ± 1.3 years); T2, end of functional treatment and prior to fixed appliances (mean age: 11.9 ± 1.3 years); and T3, long-term observation (mean age: 18.3 ± 2.1 years). The treated and the control samples were divided into pre-pubertal and pubertal groups according to skeletal maturity observed at the start of treatment. Statistical comparisons were performed with independent sample t-tests.
Results
When treatment was initiated before puberty, Class II correction was mostly confined to the dentoalveolar changes, with significant improvements of both overjet and molar relationships. On the other hand, treatment with the outset at puberty produced significant long-term improvement of sagittal skeletal relationships, which were mainly sustained by mandibular changes.
Conclusions
Treatment with removable functional appliances (Bionator or Activator) followed by full-fixed appliances produced significant skeletal long-term changes when it begins at puberty. Prepubertal Class II treatment results primarily in dentoalveolar changes.
Introduction: The purpose of this longitudinal study was to compare the craniofacial growth changes in untreated subjects with Class II Division 1 malocclusion with those in subjects with normal ...(Class I) occlusion from the prepubertal through the postpubertal stages of development, as defined by a biological indicator of individual skeletal maturity (cervical vertebral maturation method). Methods: The Class II Division 1 sample consisted of 17 subjects (11 boys, 6 girls). The Class I sample also consisted of 17 subjects (13 boys, 4 girls). The lateral cephalograms of the subjects in both groups were analyzed at 6 consecutive stages of development, from CS1 through CS6. The statistical comparisons of the growth changes in the study groups were performed with Mann-Whitney U tests. Results: Craniofacial growth in subjects with untreated Class II malocclusion is essentially similar to that in untreated subjects with normal occlusion at all developmental intervals, with the exception of significantly smaller increases in mandibular length ( P <0.001) at the growth spurt (interval CS3-CS4) and during the overall observation period (intervals CS1-CS6). Conclusions: Class II dentoskeletal disharmony does not tend to self-correct with growth in association with worsening of the deficiency in total mandibular length and mandibular ramus height.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
To analyze the long-term skeletal and dentoalveolar effects and to evaluate treatment timing of Class II treatment with functional appliances followed by fixed appliances.
A group of 40 patients (22 ...females and 18 males) with Class II malocclusion consecutively treated either with a Bionator or an Activator followed by fixed appliances was compared with a control group of 20 subjects (9 females and 11 males) with untreated Class II malocclusion. Lateral cephalograms were available at the start of treatment (mean age 10 years), end of treatment with functional appliances (mean age 12 years), and long-term observation (mean age 18.6 years). The treated sample also was divided into two groups according to skeletal maturity. The early-treatment group was composed of 20 subjects (12 females and 8 males) treated before puberty, while the late-treatment group included 20 subjects (10 females and 10 males) treated at puberty. Statistical comparisons were performed with analysis of variance followed by Tukey's post hoc tests.
Significant long-term mandibular changes (Co-Gn) in the treated group (3.6 mm over the controls) were associated with improvements in the skeletal sagittal intermaxillary relationship, overjet, and molar relationship (∼3.0-3.5 mm). Treatment during the pubertal peak was able to produce significantly greater increases in total mandibular length (4.3 mm) and mandibular ramus height (3.1 mm) associated with a significant advancement of the bony chin (3.9 mm) when compared with treatment before puberty.
Treatment of Class II malocclusion with functional appliances appears to be more effective at puberty.
To evaluate the capability of both cervical vertebral maturation (CVM) stages 3 and 4 (CS3-4 interval) and the peak in standing height to identify the mandibular growth spurt throughout diagnostic ...reliability analysis.
A previous longitudinal data set derived from 24 untreated growing subjects (15 females and nine males,) detailed elsewhere were reanalyzed. Mandibular growth was defined as annual increments in Condylion (Co)-Gnathion (Gn) (total mandibular length) and Co-Gonion Intersection (Goi) (ramus height) and their arithmetic mean (mean mandibular growth mMG). Subsequently, individual annual increments in standing height, Co-Gn, Co-Goi, and mMG were arranged according to annual age intervals, with the first and last intervals defined as 7-8 years and 15-16 years, respectively. An analysis was performed to establish the diagnostic reliability of the CS3-4 interval or the peak in standing height in the identification of the maximum individual increments of each Co-Gn, Co-Goi, and mMG measurement at each annual age interval.
CS3-4 and standing height peak show similar but variable accuracy across annual age intervals, registering values between 0.61 (standing height peak, Co-Gn) and 0.95 (standing height peak and CS3-4, mMG). Generally, satisfactory diagnostic reliability was seen when the mandibular growth spurt was identified on the basis of the Co-Goi and mMG increments.
Both CVM interval CS3-4 and peak in standing height may be used in routine clinical practice to enhance efficiency of treatments requiring identification of the mandibular growth spurt.
Objective
To analyse the craniofacial growth of a long‐term semi‐longitudinal sample of Caucasian subjects with untreated Class III malocclusion.
Setting and sample population
A total of 144 ...Caucasian subjects (of North American and Italian origin) with untreated Class III malocclusion.
Materials and methods
Subjects aged 2 years and 9 months up to 21 years and 7 months were selected. A multilevel model was used to calculate growth curves for ten variables for both each individual subject and for the whole sample.
Results
There was a statistically significant increase for total mandibular length (Co‐Gn. T2‐T1 = 8.4 mm), midfacial length (Co‐A. T2‐T1 = 3.4 mm) and lower anterior facial height (ANS‐Me. T2‐T1 = 3.8 mm). The multilevel analysis showed two points of acceleration of growth (about 3‐5 years of age and 11‐15 years of age) for seven out of ten variables. For Co‐Gn and Co‐A variables, males presented points of maximum growth delayed by 1 year in comparison with females, with a greater duration (1 year longer) and a greater total growth of about 5 mm. Active mandibular growth continued for a long time after the pubertal spurt: increases in mandibular length ended at about 17 years of age in females and at 21 years and 7 months in males.
Conclusions
Untreated Class III malocclusion showed a specific growth curve, especially for the mandible, whose excesses added up over time. In males, the amounts of mandibular and midfacial growth during the whole observation time were greater and lasted longer than in females.
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CMK, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Background: to determine the role of treatment timing in the long-term effects produced by rapid maxillary expansion and facemask therapy (RME/FM) in Class III patients. Methods: This study compared ...two sample groups treated with RME/FM followed by fixed appliances: the early prepubertal group (EPG) (17 patients; mean age before treatment (T0), 5.8 ± 0.7 years; range, 4.3–6.9 years) and the late prepubertal group (LPG) (17 patients; mean age at T0, 10.1 ± 0.8 years; range, 9.0–11.1 years). Lateral cephalograms for the two groups were examined before treatment (T0) and at a long-term observation (T1) (EPG, 19.8 ± 1.0 years; LPG, 21.0 ± 2.1 years). Independent sample t-tests were performed to compare the two groups at T0 and T1. Results: No statistically significant differences were found for any of the cephalometric variables at T0, except for the total mandibular length, overjet, and inclination of the maxillary incisors to the palatal plane, which were greater in the LPG. At T1, no statistically significant differences were detected for any of the cephalometric variables. Conclusions: There were no significant long-term differences when treating Class III patients with RME/FM, either during an early prepubertal phase (≤7 years of age) or during a late prepubertal phase (≥9 years of age).
Introduction: The purpose of this investigation was to broaden the understanding of how various skeletal, dental, and soft-tissue relationships are related to the esthetics of the smile in patients ...with malocclusions before orthodontic treatment. Methods: Images of the posed smile were captured from digital video clips of 60 growing patients (33 girls, 27 boys) seeking orthodontic treatment; they were judged by panels of laypersons and orthodontists. Discriminant analysis identified determinants of the “pleasing smile” from the results of a visual analog scale. Quantitative measurements of the soft and hard tissues were made by using the smile images, cephalometric radiographs, and study models. The esthetics of the smile were correlated with specific skeletal, dental, and soft-tissue structures in the anteroposterior, vertical, and transverse dimensions (Pearson test on nontopographic correlations). Results: The esthetic smile judgments of orthodontists agreed with those of laypersons (r >0.93). The vertical thicknesses of the lips were the most significant component of a pleasant smile, for both the orthodontists (upper lip) and laypersons (lower lip) (discriminant power: 75%). The vertical thickness of the upper lip had a significant positive correlation with the position of the maxillary incisor. Conclusions: Vertical lip thickness proved to be the most influential variable in smile esthetics. The significant relationship of incisor protrusion with the vertical thickness of the vermilion border of the upper lip must be considered when planning orthodontic treatment.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
This study aimed to determine the volumetric effects on the upper airways of growing patients with Class II malocclusion treated with the Herbst appliance (HA).
Volumetric measurements of the upper ...airways of 42 skeletal Class II malocclusion patients (mean age: 13.8 ± 1.2 years; ranging from 12.0 to 16.9 years) were assessed using cone-beam computed tomography scans acquired before treatment (T0) and approximately 1 year later (T1). The sample comprised a Herbst appliance group (HA group HAG; n = 24), and a comparison group (comparison group CG; n = 18) of orthodontic patients who had received dental treatments other than mandibular advancement with dentofacial orthopedics.
In CG, nasopharynx and oropharynx volumes decreased slightly during the observation period (9% and 3%, respectively), whereas the nasal cavity volume increased significantly (12%; P = 0.046). In HAG, there was an increase in the volume of all regions (nasal cavity, 5.5%; nasopharynx, 11.7%; and oropharynx, 29.7%). However, only the oropharynx showed a statistically significant increase (P = 0.003), presenting significant volumetric changes along the time (T1-T0) in HAG.
Mandibular advancement with the HA significantly increased the volume of the oropharynx, but no significant volumetric modifications were observed in the nasal cavity and nasopharynx.
•Oropharynx volume increased significantly after Herbst appliance therapy.•The oropharynx volume of comparison patients with Class II malocclusion was stable in the observation period.•Nasal cavity and nasopharynx volumes were stable after Herbst appliance therapy.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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