Facial soft tissue changes after transverse palatal distraction in adult patients.

This longitudinal study investigated the 3-D facial soft-tissue response to transverse palatal bone-anchored osteodistraction in 18 adult patients. Laser-scanned facial surface data were obtained for all patients before (T(0)), 6 months (T(1)) and 1 year (T(2)) after transverse palatal distraction. The averaged facial morphologies at T(0), T(1) and T(2) were calculated and compared. Sagittal and vertical measurements were obtained from lateral cephalograms to evaluate skeletal and dental movements. Pre- and immediate post-distraction dental casts were used to investigate transverse maxillary movements. Cutaneous changes were mainly observed in the paranasal regions and cheeks, in the range 1-3 mm, reflecting the underlying increase in the maxillary width. A significant enlargement of the nasal base was also demonstrated. The absolute magnitude of these facial changes was limited but clinically relevant. Variable skeletal movements were observed. These were of low magnitude and no systematic tendency could be demonstrated statistically. Significant changes were documented only with regard to orthodontic repositioning of the upper and lower incisors. The mean transverse increases in the maxillary dental arch were 6.7 mm at the intercanine, 6.8 mm at the interpremolar, and 6.1 mm at the intermolar levels.

Reconstruction of facial morphology from laser scanned data. Part I: reliability of the technique.

OBJECTIVES: The aim of this study was to evaluate the effects of scanning parameters on the precision of the data acquired using a facial laser scanner and to assess the reliability of automatic model recording in humans. METHODS: Data were acquired using a laser scanner (Cyberware 3030RGB); analysis and measurements were performed with Rapid Form 2004 software. A mannequin and six volunteers were scanned to investigate the effects of environmental conditions, positioning, head orientation, and software procedures. Precision and accuracy of the data were evaluated comparing six linear measures calculated on scanned data with those obtained directly. Two sessions with different head inclination were performed. The reliability of repeated scans was also assessed measuring the distance between the surfaces reconstructed from two separate scans of the same subject, at 12 anatomical points, in 5 subjects, during two sessions using a different head inclination. Differences were analysed using paired t-tests or analysis of variance (ANOVA). RESULTS: The accuracy of scanning was +/-0.65 mm. The development of a specific protocol resulted in a mean scanning error of 1-1.2 mm and a recording error of 0.3-0.4 mm on repeated scans of human subjects. CONCLUSIONS: This study indicates that scanning of the human face may be hampered by errors and artefacts, mainly due to movements. While the effect of trembling and involuntary movements during the exam may be minimized using faster scanning devices, comparative observation over time may be affected by unreal differences due to the uncertainty of facial expression. The overall error is, however, in the range useful for most clinical studies.

Transverse maxillary distraction with a bone-anchored appliance: dento-periodontal effects and clinical and radiological results.

In 29 adult patients presenting with maxillary deficiency, a bone-anchored palatal distractor (Surgi-Tec NV, Brugge, Belgium) was applied after osteotomy of the anterolateral walls of the maxillary sinuses, midpalatal suture, and, eventually, separation of the pterygomaxillary sutures. Expansion proceeded at a rate of 0.33-0.66 mm per day and the device was retained for 4-6 months for consolidation. Active orthodontic therapy was started after 8-10 weeks. The increment of arch width and the perimeter were evaluated using dental casts. Tooth thermal sensitivity and the periodontal side effects of treatment were monitored clinically after distraction, at device removal, and after 1 year. Bone healing was also investigated during the procedure using conventional radiological techniques. This experience confirms that transverse maxillary distraction is an effective technique in adult patients, leading to the formation of new bone. There were no noticeable intraoperative complications, but postsurgical periodontal side effects were documented. The procedure offers advantages over traditional teeth-borne appliances in terms of rapidity of treatment and the absence of mechanical forces acting on the teeth. Further evaluation is required to assess the long-term stability and periodontal consequences of this technique.

Diagnosis and treatment of retrobulbar haematomas following blunt orbital trauma: a description of eight cases.

Retrobulbar haematoma following blunt orbital trauma is a rare, but potentially serious, complication, since it can evolve rapidly from visual impairment to permanent loss of vision. This sight-threatening situation most commonly arises from orbital bleeding accompanying undisplaced fractures of the orbital walls, an event that increases the pressure inside the orbit and results in vascular damage to the optic nerve. The clinical presentation includes pain, exophthalmos with proptosis, and internal ophthalmoplegia, with impairment or loss of the pupillary reflex. A thin-layer orbital CT scan is an essential diagnostic aid. Any delay between the onset of symptoms and treatment can have a significant effect on functional recovery. Therapy is based on orbital decompression, via different surgical approaches, with the intention of reducing the pressure on the nerve and vascular structures inside the orbit. This paper presents eight cases of retrobulbar haematoma and their follow-up, in detail.