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Maxillary transverse discrepancy is often diagnosed in childhood. The evaluation of morphological characteristics of the maxilla is crucial for appropriate treatment of this condition, however conventional diagnostic method is based on visual inspection and transversal linear parameters. In this paper, we described a user-friendly diagnostic digital workflow based on the surface-to-surface analysis. We also described a case report.A 6-year-old female patient presenting mild transversal maxillary deficiency associated with functional posterior crossbite was treated by using maxillary removable appliance. In this respect, the appliance was designed in accordance to the morphological characteristics of the maxilla obtained by using the diagnostic digital work-flow and the maxillary surface-to-surface analysis.The present user-friendly diagnostic digital workflow based on surface-to-surface analysis helps clinicians to detect specific morphological characteristics of the maxilla, such as shape and area of asymmetry, in order to reach a comprehensive diagnosis and choose the correct biomechanics for treating the condition.

OBJECTIVES: To compare transverse skeletal changes produced by rapid (RME) and slow (SME) maxillary expansion using low-dose computed tomography. The null hypothesis was that SME and RME are equally effective in producing skeletal maxillary expansion in patients with posterior crossbite. SETTING AND SAMPLE POPULATION: This study was carried out at the Department of Oral Sciences, University of Naples Federico II, Italy. Twelve patients (seven males, five females, mean age ± SD: 10.3 ± 2.5 years) were allocated to the SME group and 14 patients (six males, eight females, mean age ± SD: 9.7 ± 1.5 years) to the RME group. MATERIALS AND METHODS: All patients received a two-band palatal expander and were randomly allocated to either RME or SME. Low-dose computed tomography was used to identify skeletal and dental landmarks and to measure transverse maxillary changes with treatment. RESULTS: A significant increase in skeletal transverse diameters was found in both SME and RME groups (anterior expansion = 2.2 ± 1.4 mm, posterior expansion = 2.2 ± 0.9 mm, pterygoid expansion = 0.9 ± 0.8 mm). No significant differences were found between groups at anterior (SME = 1.9 ± 1.3 mm; RME = 2.5 ± 1.5 mm) or posterior (SME = 1.9 ± 1.0 mm; RME = 2.4 ± 0.9 mm) locations, while a statistically significant difference was measured at the pterygoid processes (SME = 0.6 ± 0.6 mm; RME = 1.2 ± 0.9 mm, p = 0.04), which was not clinically relevant. CONCLUSION: Rapid maxillary expansion is not more effective than SME in expanding the maxilla in patients with posterior crossbite.

The aim of this study is to assess if, and to what extent, myotonic dystrophy can affect the craniofacial growth pattern.The research was conducted on a sample of 27 patients with Steinert's myotonic dystrophy (study group). Each subject underwent a clinical examination with impression-taking and intra- and extraoral photographs. A latero-lateral projection teleradiography in the mirror position was also taken and a cephalometric examination was performed. The assessed values were compared with those obtained from a group of healthy subjects (control group).Statistical analysis of the data obtained from the myotonic patients who developed the disease during the growth phase revealed alterations in the transversal plane and, to an even greater extent, the vertical one, with a high frequency of anterior open bite. Discussion and conclusions Regarding the pathogenesis of these types of skeletal dysplasias, the authors hypothesise a posterior rotation growth pattern, resulting from gravitational force prevailing over the deficit of the elevator muscles.

Background and objectives: The aim of the present paper is to use low-dose computed tomography (CT) to evaluate the changes in the midpalatal suture density in patients treated with rapid maxillary expansion (RME) and slow maxillary expansion (SME). Materials and Methods: Thirty patients (mean age 10.2 &plusmn, 1.2 years) were retrospectively selected from the existing sample of a previous study. For each patient, a low-dose computed tomography examination was performed before appliance placement (T0) and at the end of retention (T1), seven months later. Using the collected images, the midpalatal suture density was evaluated in six regions of interest. Results: No significant differences were found between the timepoints in the rapid maxillary expansion group. Three out of six regions of interest showed significant decreases between the timepoints in the slow maxillary expansion group. No significant differences were found in comparisons between the two groups. Conclusions: The midpalatal suture density showed no significant differences when rapid maxillary expansion groups were compared to slow maxillary expansion groups, suggesting that a similar rate of suture reorganization occurs despite different expansion protocols.

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

Background The aim of this study was to evaluate the amount of radiation doses absorbed by soft tissues (entrance skin dose) with a low-dose spiral computed tomography (CT) protocol compared to conventional X-ray techniques commonly used in orthodontics. Methods The amount of skin dose has been evaluated using a tissue-equivalent head-neck radiotherapy humanoid phantom with thermoluminescent dosimeters placed at the level of eye lens, parotid glands, and thyroid glands. CT images have been taken using a Sensation 16 Siemens CT scan and a low-dose protocol (15 mAs, 1 pitch, 2.5 mGy (CTDIvol), 80 kV, 1-mm slice thickness). Results The difference in image quality between traditional X-ray techniques and low-dose spiral CT was statistically significant (P Conclusions Our protocol allows a more accurate orthodontic diagnosis without an increase of radiological risk for the patients in comparison to traditional X-ray techniques.