Rosamaria Fastuca

Effects of orthopedic maxillary expansion on nasal cavity size in growing subjects: A low dose computer tomography clinical trial

OBJECTIVE The aim of this retrospective clinical trial was to evaluate the effects of rapid maxillary expansion on skeletal nasal cavity size in growing subjects by use of low dose computer tomography. METHODS Eight Caucasian children (three male; five female) with a mean age of 9.7 years (SD±1.41) were the final sample of this research that underwent palatal expansion as a first phase of orthodontic treatment. The maxillary expander was banded to the upper first molars and was activated according a rapid maxillary expansion protocol. Low-dose computer tomography examinations of maxilla and of the low portion of nasal cavity were performed before inserting the maxillary expander (T0) and at the end of retention (T1), 7 months later. A low-dose computer tomography protocol was applied during the exams. Image processing was achieved in 3 steps: reslicing; dental and skeletal measurements; skeletal nasal volume computing. A set of reproducible skeletal and dental landmarks were located in the coronal passing through the first upper right molar furcation. Using the landmarks, a set of transverse linear measurements were identified to estimate maximum nasal width and nasal floor width. To compute the nasal volume the lower portion of the nasal cavity was set as region of interest. Nasal volume was calculated using a set of coronal slices. In each coronal slice, the cortical bone of the nasal cavity was identified and selected with a segmentation technique. Dependent t-tests were used to evaluate changes due to expansion. For all tests, a significance level of P<0.05 was used. RESULTS Rapid maxillary expansion produced significant increases of linear transverse skeletal measurements, these increments were bigger in the lower portion of the nasal cavities: nasal floor width (+3.15 mm; SD ± 0.99), maximum nasal width (+2.47 mm; SD ± 0.99). Rapid maxillary expansion produced significant increment of the total nasal volume (+1.27 cm(3) ± SD 0.65). The anterior volume increase was 0.58 cm(3) while the posterior one was 0.69 cm(3). CONCLUSION In growing subjects RME is able to significantly enlarge the dimension of nasal cavity. The increment is bigger in the lower part of the nose and equally distributed between the anterior e the posterior part of the nasal cavity.

Airway compartments volume and oxygen saturation changes after rapid maxillary expansion: A longitudinal correlation study

OBJECTIVE To evaluate changes in airway volumes and respiratory performance in patients undergoing rapid maxillary expansion and determine whether any correlations exist between the morphological and respiratory functional modifications induced by rapid maxillary expansion and pretreatment airway stenosis. MATERIALS AND METHODS Fifteen patients (11 females and 4 males; mean age, 7.5 ± 0.3 years) were enrolled in the study. Each patient underwent cone beam computed tomography and polysomnography examination before rapid maxillary expansion and after the removal of the maxillary expander 12 months later. The airway regions were segmented and the volumes were computed. RESULTS The upper, middle, and lower airway volumes were significantly increased 2305 mm(3), 1144 mm(3), and 1915 mm(3), respectively. Similarly, oxygen saturation was increased (+5.3%) and the apnea/hypopnea index was improved (-4.2 events). All the observed modifications were statistically significant (P < .05). Baseline middle and lower airway volume showed a significant negative correlation with the oxygen saturation modification. CONCLUSIONS The results of this study showed that when rapid maxillary expansion is performed in subjects having posterior crossbite, oxygen saturation is improved. The improvement is greater in subjects having more reduced middle and lower airway volumes.

Correlation Assessment between Three-Dimensional Facial Soft Tissue Scan and Lateral Cephalometric Radiography in Orthodontic Diagnosis

Purpose. The aim of the present prospective study was to investigate correlations between 3D facial soft tissue scan and lateral cephalometric radiography measurements. Materials and Methods. The study sample comprised 312 subjects of Caucasian ethnic origin. Exclusion criteria were all the craniofacial anomalies, noticeable asymmetries, and previous or current orthodontic treatment. A cephalometric analysis was developed employing 11 soft tissue landmarks and 14 sagittal and 14 vertical angular measurements corresponding to skeletal cephalometric variables. Cephalometric analyses on lateral cephalometric radiographies were performed for all subjects. The measurements were analysed in terms of their reliability and gender-age specific differences. Then, the soft tissue values were analysed for any correlations with lateral cephalometric radiography variables using Pearson correlation coefficient analysis. Results. Low, medium, and high correlations were found for sagittal and vertical measurements. Sagittal measurements seemed to be more reliable in providing a soft tissue diagnosis than vertical measurements. Conclusions. Sagittal parameters seemed to be more reliable in providing a soft tissue diagnosis similar to lateral cephalometric radiography. Vertical soft tissue measurements meanwhile showed a little less correlation with the corresponding cephalometric values perhaps due to the low reproducibility of cranial base and mandibular landmarks.

Cellular Midpalatal Suture Changes after Rapid Maxillary Expansion in Growing Subjects: A Case Report

The present case report aimed to investigate immediate histologic changes in midpalatal suture in humans following rapid maxillary expansion compared to control. Three patients (mean age 8.3 ± 0.9 years) were enrolled in the case report and underwent midpalatal suture biopsy. Two patients underwent treatment before biopsy. The third patient did not show transversal maxillary deficiency and was enrolled as a control. Biopsy samples of midpalatal suture at 7 (subject 1) and 30 days (subject 2) after maxillary expansion as well as of one control (subject 3) were collected and processed for histology. In the control (subject 3) inter-digitations at the palatal suture gap were observed. At 7 days (subject 1) mature bone with small marrow spaces and trabecular bone with the peculiar storiform appearance inside the soft tissue and collagen fibers running parallel only in the central part were present. At 30 days (subject 2), a greater number of newly-formed bone trabeculae with a perpendicular orientation to the long axis of the suture could be seen. At 30 days the fibrous component of bone tissue was less represented compared to the sample at 7 days. Data from the preliminary histological results showed that bone formation was observed in the gap after rapid maxillary expansion, although the healing process was still ongoing.

Digital Dynamic 3D Monitoring of Lower Incisors Intrusion in Lingual Orthodontics

Objective: The aim of the present study is to propose a 3-dimensional evaluation of lower intrusion obtained with lingual orthodontics considering not only the crowns but also dental roots. Methods: 9 adult patients underwent fixed lingual orthodontic treatment with i-TTя lingual brackets system for the correction of crowding in the lower arch associated with a deep overbite. Initial records, consisting of photos, CBCTs and intraoral scans were collected. Threshold segmentation of the CBCT was performed to generate a three-dimensional virtual model of each the teeth of the lower arch, superimposed with the crown of the same teeth obtained by intraoral scan models to generate a complete set of digital composite lower arch The same procedure was performed to monitor one key step of the i-TTЯ technique consisting in lower incisors intrusion (T2). T1-T2 three-dimensional superimposition and color displacement maps were generated to measure and evaluate the movements obtained at the lower arch. Results: The root displacement of the incisors during their intrusion in the early stage was totally “bone-safe” in the 88.9% (8 of 9) of the cases observed. No significant extrusion of the premolars used as anchorage unit was measured. Conclusion: This method has proved to be an accurate and reliable approach to dynamically visualize the 3-dimensional positions of the teeth, including their roots, with no additional radiation for in-progress treatment monitoring. The 3-dimensional evaluation showed that the employed lingual appliance allowed to obtain significant lower incisors intrusion with negligible undesired extrusion of premolars employed as anchorage teeth.

No Compliance Correction of Class II Malocclusion in Growing Patients Whit HERBST Appliance: A Case Report

Background: Class II malocclusion is the most common sagittal skeletal discrepancy, with a prevalent skeletal pattern of mandibular retrusion. The correction of mandibular retrusion with functional removable appliance needs a good patient’s compliance; for this reason, some clinicians prefer to use no compliance apparatus. Objective: Objective of the present therapy note is to demonstrate that the use of no compliance apparatus can provide a good correction of skeletal class II malocclusion. Methods: In the present study, authors report a therapy note referred to a 10 years old patient, woman, affected by Class II, with mandibular retrusion and deep bite, treated in 2013 at the Dep. of Orthodontics of Messina University. An orthodontic treatment has been planned with the aim of stimulating mandibular growth; an Herbst appliance with a cantilever design, bonded on first maxillary and mandibular molars, has been used. After eleven months of functional therapy a bilateral molar class I have been obtained. Results: In the therapy note proposed, authors obtained a resolution of mandibular retrusion, a correction of overjet, overbite and dental crowding in both arches, and a bilateral molar and canine class I has been achieved. Conclusion: Herbst appliance seems to be efficient in the correction of II Class Malocclusion, independently from patient’s cooperation; moreover , early correction of Class II malocclusion with functional appliances produces several clinical advantages.

Skeletal and Dental Effectiveness of Treatment of Class II Malocclusion With Headgear: A Systematic Review and Meta-analysis

Objective To evaluate the skeletal and dental effects of headgear treatment by systematically reviewing the best available scientific evidence. Materials and Methods A survey of articles published up to February 2017 investigating the effects of headgear in the treatment of patients with class II malocclusion was performed using 19 electronic databases. Only randomized clinical trials and prospective controlled clinical trials investigating growing patients with class II malocclusion treated with headgear were included. Two authors performed independently study selection, data extraction, and risk of bias assessment. All pooled data analyses were performed using the random‐effect model. Statistical heterogeneity was evaluated. Results In total, 6 trials were included (4 randomized clinical trials and 2 prospective controlled clinical trials), grouping data from 337 patients (170 treated patients and 167 untreated controls). The ages of the patients varied across the studies, but the majority of the trials had a sample with an age range between 8 and 9 years. The times of daily wear of the appliance varied across studies from 8 to 14 h/d. The significant mean differences in treatment effects compared with the untreated controls were −1.41° per year for SNA angle cephalometric parameter (95% confidence interval [CI]: −2.25° to −0.56°), −0.57 mm/y for anterior maxillary displacement (95% CI: −0.75 to −0.40 mm), −1.42° per year for ANB angle cephalometric parameter (95% CI: −2.12° to −0.72°), and −1.31 mm/y for the overjet cephalometric parameter (95% CI: −2.34 to −0.29 mm). Conclusion Headgear treatment is effective in restricting sagittal maxillary growth and reducing the overjet in the short term.

Effects of rapid vs slow maxillary expansion on nasal cavity dimensions in growing subjects: A methodological and reproducibility study

AIM To evaluate the methodological feasibility of a RCT comparing skeletal changes of nasal cavity size obtained with RME and SME, assessed via CBCT. MATERIALS AND METHODS Twenty Caucasian children with a mean age of 10.4 years were recruited and allocated to receive RME (10 subjects, mean age 10.4 years) or SME (10 subjects, mean age 10.5 years). INCLUSION CRITERIA constricted maxillary arch, upper and lower first molars erupted, unilateral or bilateral posterior crossbite. EXCLUSION CRITERIA age above 15 years, history of previous orthodontic treatment, periodontal disease, systemic disease affecting craniofacial growth, or craniofacial congenital syndrome. CBCT examinations were performed before treatment (T0) and 7 months after expander removal (T1). Changes of nasal width (NW), palatal width (PW) and total nasal volume (TNV) were assessed; palatal and nasal expansion was also calculated as a percentage of the increase of intermolar width IMW (PW% and NW%). RESULTS The correlation between the first and the second readings ranged from 0.991 to 0.995 for linear measurements and was of 0.915 for volumetric measurements. The method error, as described by the value of ?, was in general less than 0.3 mm for linear measurements and 0.372 cm³ for volumetric measurements. All linear transverse skeletal and dental measurements and the nasal volume increased with both RME and SME protocols. CONCLUSION The reported methodology can be reasonably used to investigate the transverse dimension of nasal cavity. The PW% and NW% parameters more accurately described the efficacy of the two expansion protocols as compared to their corresponding absolute measurement (PW and NW).

Maxillary expansion and breathing function: Where we are now?

According to the anatomical proximity between nasal cavity and hard palate, an orthopedic expansion of the former might occur as consequence of the RME treatment. This hypothesis has initially been investigated decades ago. In particular, earlier studies[4,5] evaluated the advantages of RME treatment in improving nasal airflow in patients with nasal stenosis. It was later suggested that RME treatment triggers effects on nasal width[6‐8] and volume.[9‐14] Indeed, some studies[15,16] showed a reduction in nasal airway resistance after RME treatment. Consistently, a more recent investigation[17] reported up to 45% increase in nasal cross‐sectional areas after expansion. In spite of this evidence, considering the V‐shaped opening pattern of the midpalatal suture,[4,5] the only purpose of increasing respiratory performance has been reported as not sufficient to indicate an RME treatment.[17]

Measurements of orbital protrusion from childhood to young adulthood.

Background:Ocular protrusion is usually measured as the deepest part of the lateral orbital rim to the apex of the cornea. Several studies have been carried out to propose normative data for ocular protrusion according to different age ranges. The protrusion of the eyeball seemed to increase during childhood and adolescence and become stable after the late teens during adulthood. Relationships of ocular protrusion with age are still not completely clarified. The purpose of the current retrospective study was to investigate ocular protrusion on lateral x-rays at different growth stages. Methods:Ninety-five patients were retrospectively selected and divided into 5 different groups according to ages. Subjects were of both sexes with an age range from 5 to 20 years (mean 12.3 years). The cephalometric analysis proposed in the current study allowed to successfully evaluate sagittal relationships of the orbital-globe and the orbital-cavity in growing patients. All other sagittal and vertical measurements were successfully computed by one trained operator. Results:Analysis of variance results with post hoc corrections showed for the orbital measurements indicating a significant increase of the orbital protrusion from childhood to pubertal stage. Conclusions:Ocular protrusion measurements showed significant increase from childhood (5–8 years) to teen age (13–15 years) and remained stable after the pubertal growth spurt (17–20 years) in the examined sample of patients.