Radiography-based score indicative for the pathogenicity of bacteria in odontogenic infections.

OBJECTIVE: To develop a new radiography-based score to assess the potential of bacteria to cause odontogenic infections derived from the occurrence of bacteria at small or large radiographical lesions. MATERIALS AND METHODS: The patients analyzed were a sub-population from a large randomized clinical trial comparing moxifloxacin and clindamycin in the treatment of inflammatory infiltrates and odontogenic abscesses. Routine radiographs were used to analyze the area of the periapical radiolucent lesions. Lesions were stratified by their radiographically measured area as large (>9 mm(2)) or small (≤9 mm(2)). A risk ratio was calculated for each species from the frequency of their occurrence in large vs in small lesions. RESULTS: Fifty-one patients, 19 with abscesses and 32 with infiltrates, were evaluated. Overall, the radiographical lesion areas ranged from 0.4-46.2 mm(2) (median = 9 mm(2)). An increased risk (risk ratio >1) to occur at large abscess lesions was observed for Prevotella (P.) oralis, P. buccae, P. oris, P. intermedia, Fusobacterium nucleatum and Streptococcus (Strep.) anginosus group. An increased risk to occur at large infiltrate lesions was found for Strep. salivarius, Strep. parasanguis, Strep. anginosus group, Capnocytophaga spp., Neisseria (N.) sicca, Neisseria spp., Staphylococcus (Staph.) aureus, P. intermedia, P. buccae, Prevotella spp. and P. melaninogenica. CONCLUSIONS: The radiography-based score suggests that certain Prevotella spp., F. nucleatum and Strep. anginosus groups play a crucial role in the pathogenesis of odontogenic abscesses, and that various streptococci, Neisseria spp., Capnocytophaga spp., Staph. aureus and Prevotella spp. are involved in the pathogenesis of odontogenic infiltrates.

Correlation of age and ossification of the medial clavicular epiphysis using computed tomography.

OBJECT: The aim of this study was the examination of relationship between the age and the ossification of medial epiphysis of the clavicle referred to CT examination. MATERIALS AND METHODS: Concerning the epiphyseal ossification of the clavicle CT's of 100 patients (50 male and 50 female) between 16 and 25 years (10 patients for each year) were analyzed by three viewers. RESULTS: In the legal relevant age segment (16-25a) we saw a turnover from stage 3 to stage 4 at the age of 21 years. The calculated empiric distribution function showed 95% of stage 4 over 21 years while 75% of the patients with stage 3 were under 21 years. A reconstruction kernel suitable for osseous structures should be used, images should be viewed or presented in a bone window. CONCLUSION: According to these results it can be concluded that a person with stage 4 is probably 21 years or older, while a stage 3 leads to an estimated age under 21 years. On the other hand, a confidence level of 99.67% is not reached. Therefore, CT of the medial epiphysis of the clavicle will only be suitable for age estimation around the age of 21 years, if this relevant statistic obstacle is defeated. Bearing this in mind, further studies are needed to evaluate slice thickness as the most critical parameter.

Evaluation of quality of reformatted images from two cone-beam computed tomographic systems.

PURPOSE: The aim of the study was to compare image quality of two different systems based on cone-beam computed tomography (CBCT). STUDY DESIGN: Primary and secondary reconstructions were performed from data sets of the Siremobil Iso-C(3D) (Siemens Medical Solutions, Erlangen, Germany) and the NewTom 9000 (NIM s.r.l., Verona, Italy) using a dried human skull. Using defined anatomical structures, image quality was analysed by 10 examiners using a ranking scale. RESULTS: Regarding image quality there was no statistically significant difference between the two systems compared. CONCLUSION: The preliminary results show, that imaging of the facial skeleton using the Siremobil Iso-C(3D) can be performed with a quality comparable to the NewTom 9000.

Postoperative imaging of zygomaticomaxillary complex fractures using digital volume tomography.

PURPOSE: Three-dimensional imaging using digital volume tomography after reduction of zygomaticomaxillary complex fractures was performed and evaluated. PATIENTS AND METHODS: Ten patients admitted for surgical treatment of zygomaticomaxillary complex fractures were included in the study. All patients were male, aged 17 to 81 years (average, 43.8 years). Preoperative diagnostics and surgical treatment involving open reduction under general anesthesia were performed as usual. One to 3 days (average, 1.6 days) postoperatively, a digital volume tomography data set was generated using the NewTom 9000 (NIM s.r.l., Verona, Italy). After DICOM-import in eFilm Workstation 1.8.3 (Merge Technologies Inc, Milwaukee, WI), axial, coronal, and sagittal reconstructions were evaluated by 6 examiners with the help of 5 defined criteria. RESULTS: One data set was sufficient to visualize all fracture sites of the midface in all patients. Postprocessing using eFilm was successfully performed in all cases. Best scoring results were found regarding bony anchorage of screws and fitting of plates. Remarkable was the low level of metal artifacts in primary and secondary reconstructions, even in close proximity of the material. Most difficulty was encountered during the identification of the medial orbital wall, especially next to poorly ventilated ethmoidal cells. Osseous structures of older patients with decreased bone density proved difficult to visualize. CONCLUSION: Digital volume tomography using the NewTom 9000 is suitable for assessment of postoperative results after zygomaticomaxillary complex reduction.