Patient comfort in periapical examination using digital receptors.

OBJECTIVES: The aim of this study was to compare digital and conventional radiography with regard to patient comfort during periapical radiographic examination. METHODS: 300 patients were submitted to a simulation of a radiographic periapical examination of a dentate region using conventional intraoral radiographic film (Kodak Insight) with and without the use of an RINN film holder, a Schick charge-coupled device (CCD) sensor, a Visualix CCD sensor and a Denoptix phosphor plate. The patients were asked to score how they felt in terms of comfort on a 100 mm visual analogue scale. The Wilcoxon test (alpha = 0.05) was applied to compare the comfort score of different types of imaging receptor from each simulated radiographic region reported by the patients. RESULTS: The median of the "comfort data" according to the type of imaging receptor was 40 mm for conventional intraoral radiographic film with the use of the film holder, 85 mm for conventional intraoral radiographic film without the film holder, 80 mm for Schick and Visualix receptors, and 90 mm for the Denoptix receptor. CONCLUSIONS: Denoptix was the most comfortable imaging receptor, followed in decreasing order by Schick and Visualix, conventional intraoral radiographic film without using the film holder and conventional intraoral radiographic film with a film holder.

Effect of image compression of digital lateral cephalograms on the reproducibility of cephalometric points.

OBJECTIVES: To evaluate the influence of JPEG quality factors 100, 80 and 60 on the reproducibility of identification of cephalometric points on images of lateral cephalograms, compared with the Digital Imaging and Communications in Medicine (DICOM) format. METHODS: The sample was composed of 30 images of digital lateral cephalograms obtained from 30 individuals (15 males and 15 females) on a phosphor plate system in DICOM format. The images were converted to JPEG with quality factors 100, 80 and 60 with the aid of software, adding up to 90 images. The 120 images (DICOM, JPEG 100, 80 and 60) were blinded and 12 cephalometric points were identified on each image by three calibrated orthodontists, using the x-y coordinate system, on a cephalometric software. RESULTS: The results revealed that identification of cephalometric points was highly reproducible, except for the point Orbitale (Or) on the x-axis. The different file formats did not present a statistically significant difference. CONCLUSIONS: JPEG images of lateral cephalograms with quality factors 100, 80 and 60 did not present alterations in the reproducibility of identification of cephalometric points compared with the DICOM format. Good reproducibility was achieved for the 12 points, except for point Or on the x-axis.

Evaluation of optical density of the midpalatal suture 3 months after surgically assisted rapid maxillary expansion.

OBJECTIVES: This study evaluated new bone formation at the midpalatal suture after surgically assisted rapid maxillary expansion (SARME) by optical density analysis. METHODS: The study population consisted of 18 patients, 10 males and 8 females. All patients presented maxillary atresia with posterior crossbite and were submitted to SARME. Maxillary occlusal radiographs were taken at three stages (before SARME, immediately after SARME and after 3 months). Three patients did not attend the session at the 3-month period for achievement of the occlusal radiography and thus were excluded, leading to a final sample of 15 patients. Two regions were selected and analysed at each stage. Region A measured 8 x 1 mm(2) and was located 1.2 cm from the tangent to the maxillary central incisors at the region of the midpalatal suture. Region B measured 5 x 9 mm(2) and was located 4.3 cm from the tangent to the maxillary central incisors at the region of the midpalatal suture. An aluminium scale (step wedge) with eight steps varying from 1 mm to 8 mm was adapted at the end of the films. Radiographs were taken on a Spectro 70X machine (Dabi Atlante, Ribeirão Preto, Brazil) set at 70 kVp and 10 mA with an exposure time of 1.0 s. Radiographs were scanned using a Power Look 1000 scanner (Umax, Taiwan, China) and a computer Dimension E510 (Dell Computer, Taiwan, China). Optical density analysis was performed after digitization of radiographs using the software Image Tool (UTHSCSA, San Antonio, TX). RESULTS: Statistical analysis of region A revealed statistically significant differences between Stages I and II (P=0.0001), Stages II and III (P=0.0001) and Stages I and III (P=0.0003). In region B, statistically significant differences were observed between Stages I and II, I and III and II and III (P=0.0018, P=0.0003 and P=0.0003, respectively). CONCLUSIONS: Optical density analysis improves post-treatment control of SARME procedures by surgeons and orthodontists. After 3 months, new bone formation at the midpalatal suture is not complete.

Clinical and radiographic presentation and preparation of the prototyping model for pre-surgical planning in Apert's syndrome.

Acrocephalosyndactyly, or Apert's syndrome, described nearly a century ago, is a craniofacial dysostosis, an autosomal dominant condition characterized by severe development disturbances of the craniofacial region including bilateral coronal synostosis associated with midface hypoplasia, exophthalmia, hypertelorism, symmetric syndactyly of the hands and feet, cone-shaped calvarium, pharyngeal attenuation and malocclusion. The aim of this study was to assess clinical and computed tomography (CT) imaging patterns of a non-operated patient with Apert's syndrome, correlating the cranium, face and the skull base bone abnormalities. Three-dimensional images were generated from spiral CT scans in order to produce a prototyping model in polyamide material. Clinical examination determined that syndactyly of the hands and feet, pseudocleft in the midline palate and midface hypoplasia were present. The surgical model allowed the analysis of some abnormalities regarding to calvaria morphology, nasal bones and maxilla, improving the criteria for a case diagnosis and surgical plan.