Case report of segmental odontomaxillary dysplasia with cutaneous manifestations.

BACKGROUND: Segmental odontomaxillary dysplasia is an uncommon nonhereditary growth disorder that affects the maxilla, gums and ipsilateral dentition. The disorder is diagnosed mainly based on dental (over-retention of primary teeth, dental agenesis and diastemas) and bone findings (bone sclerosis, irregular trabeculation of immature bone and reduced maxillary sinus). This paper provides a case report. CASE REPORT: A 5-year-old child with skin manifestations including hypertrichosis, facial erythema and pigmented nevus was diagnosed with type II segmental odontomaxillary dysplasia based on clinical, radiographic and histopathological analysis. CONCLUSION: The skin findings can help with the suspicion of segmental odontomaxillary dysplasia, although the definitive diagnosis is typically established by a paediatric dentist based on clinical and radiological findings.

Cone Beam Computed Tomography evaluation of palatal bone thickness for miniscrew placement in Down's syndrome.

OBJECTIVES: To quantify palatal bone thickness (PBT) in Down's syndrome (DS) patients in order to identify the best areas for miniscrew placement. DESIGN: The study group was formed of 40 DS patients (25 male and 15 female) with a mean age of 18.4±6.3 years (range, 9-40 years). A control group of 40 non-syndromic age- and sex-matched individuals was selected. Maxillary CBCT images were available for all participants. Coronal sections of the hard palate were selected at 4, 8, 16 and 24mm posterior to the distal wall of the incisive foramen. PBT measurements were performed at 20 selected points on these coronal sections at the midline and at 3 and 6mm to right and left of the suture. RESULTS: Overall, PBT was similar in DS and controls and it was not affected by age or sex. In both groups PBT decreased progressively with increasing distance from the posterior wall of the nasopalatine foramen in an anteroposterior direction, except along the median palatal suture. PBT along the suture was lower in DS than in controls in all the paracoronal image planes (P=0.02, 0.007, 0.01 and 0.02 at 4mm, 8mm, 16mm and 24mm, respectively, from the incisive foramen). PBT at the most anterior paramedian locations was also lower in DS than in controls (P=0.02 and 0.03, respectively, 3mm to the right and left of midline). CONCLUSIONS: In DS individuals, the most suitable area for miniscrew placement in terms of bone volume is the median palatal suture, irrespective of age or sex, as occurs in the general population, followed by the paramedian sites closest to the incisive foramen.

Morphometry of the hard palate in Down's syndrome through CBCT-image analysis.

OBJECTIVES: To define the morphometry of the hard palate in Down's syndrome (DS) on cone beam computed tomography (CBCT) images. SETTING AND SAMPLE POPULATION: Santiago de Compostela University (Spain). The study group included 40 white DS individuals aged 10 to 40 years (mean = 18.8 ± 7.3 years), 25 males and 15 females. The control group consisted of 40 individuals matched for age and sex were selected. MATERIAL & METHODS: Nine measurements were taken on the CBCT images. Axial plane: anteroposterior length (aAPL) and arch length (aARL); sagittal plane: anteroposterior length (sAPL), maximum height (sMH) and sagittal arch (sAR); coronal plane: interdental width (cIDW), height (cHE), skeletal width (cSW) and coronal arch (cAR). RESULTS: aAPL, aARL, sAPL, sMH, sAR, cMH and cAR were comparable in the two groups. cIDW and cSW were greater in controls than in DS. We found no statistically significant differences between males and females with DS. In the controls, sAPL and sAR were greater in males than females. In DS, age only had a statistically significantly increasing effect on aAPL and sAPL. In the controls, age significantly affected sAR and cHE. CONCLUSION: The hard palate is narrower in DS than in controls, but the anteroposterior measurements and the height of the vault are comparable in both groups.

Three-dimensional numerical simulation of dental implants as orthodontic anchorage.

Endosseous oral implants have been used as orthodontic anchorage in subjects with multiple tooth agenesis, and their application under orthodontic loading has been demonstrated clinically and experimentally. The aim of this investigation was to examine three-dimensional (3D) bone and implant finite element (FE) models. The first model assumed that there was no osseointegration and the second that full osseointegration had occurred. These models were used to determine the pattern and distribution of stresses within the ITI-Bonefit endosseous implant and its supporting tissues when used as an orthodontic anchorage unit. The study examined a threaded implant placed in an edentulous segment of a human mandible with cortical and cancellous bone. The results, using both models, indicated that the maximum stresses were always located around the neck of the implant, in the marginal bone. Thus, this area should be preserved clinically in order to maintain the bone-implant interface structurally and functionally.

In-plane electronic speckle pattern of interference (ESPI) with optical fibre system applied to the study of the human jaw.

The standard illumination set-up for measurement of in-plane displacement in electronic speckle pattern of interference (ESPI) requires the use of two oblique coherent beams for the illumination of the object. These two beams define a direction in the plane perpendicular to the optical axis in which the displacement can be measured, while in the perpendicular direction the interferometer has no sensitivity. In this paper, a new ESPI system for the measurement of in-plane displacements is used. The novelty presented by this assembly is the use of optical fibres to split and guide the light beams. In this way, it is possible to vary with great precision and ease the direction of the projected beams and, consequently, the direction of the plane in which the displacements undergone by the object can be studied. This set-up makes possible the study of objects with complex geometries, which have deformations with unknown symmetry. We present results obtained with this interferometer applied to the study of the mechanical behaviour of the human jaw.