An investigation of the ability of computerized axiography to reproduce occlusal contacts.

Intraoral excursive tooth contacts were compared with contacts made on both an unprogrammed and programmed Denar D5a articulator. 20 subjects were used to obtain study models which were mounted using a facebow transfer in Intercuspal Position. Cadiax Data was used to customise the articulator and left and right intraoral excursive contacts were examined and transferred from the mouth to the articulator using occlusagram wax bites. Using image analysis, the proportion of corresponding tooth contacts and the percentage of corresponding tooth contacts were significantly better when the articulator was programmed.

Consensus review: A method of assessment of calcifications that appropriately undergo a six-month follow-up.

RATIONALE AND OBJECTIVES: Breast calcifications seen on mammography may be associated with benign conditions or malignancies. Accurate characterization of these calcifications is crucial to providing optimal care that may spare women unnecessary biopsies and appropriately allow interval mammography. The purpose of this study is to determine if consensus characterization of calcifications by two breast imaging experts using standardized criteria can establish that follow-up is a safe option. MATERIALS AND METHODS: For this retrospective study, our breast imaging database was reviewed and the cases imaged between the years 1999 and 2001 were used to identify patients with calcifications who were recommended for a six-month follow-up or biopsy. All cases had been prospectively assessed by at least two expert breast imagers using standardized features to assess the findings before a recommendation for follow-up or a biopsy was made. A retrospective chart review examining the radiology reports was done to determine the percentage of women from each of the two groups who developed malignancies. RESULTS: Of 744 patients who had mammographically identified clusters of calcifications, 490 clusters (409 single and 81 multiple) were diagnosed as probably-benign, and a short-interval 6-month follow-up was recommended. Of these calcifications followed for three years, only two (0.5%) of the single clusters proved to be malignant, and malignancy was diagnosed at the 12-month follow-up examination. In both cases, the women were diagnosed with ductal carcinoma in situ (DCIS). Of 254 clusters recommended for biopsy, 242 (215 single and 27 multiple) underwent biopsy. A total of 70 cancers were diagnosed: 54 (77.1%) were DCIS and 16 (22.9%) were primary invasive mammary carcinoma (10 cases of invasive ductal carcinoma, 3 cases of invasive lobular carcinoma, 2 cases of invasive ductal carcinoma with DCIS, and one case of invasive mucinous carcinoma with DCIS). Twenty-nine percent of women who had a biopsy performed had calcifications associated with malignancy. In contrast, in the women whose calcifications were followed by mammography, only 0.5% went on to develop malignancies. CONCLUSION: Consensus review of calcifications by two breast imagers using standardized criteria is a safe follow-up option.

The positive predictive value for diagnosis of breast cancer full-field digital mammography versus film-screen mammography in the diagnostic mammographic population.

RATIONALE AND OBJECTIVES: Diagnostic mammography is performed on women with clinical symptoms that suggest breast cancer or women for whom further mammographic evaluation has been requested because of an abnormal screening mammography. We assessed whether the use of full-field digital mammography would improve the positive predictive value (PPV) for the diagnosis of breast cancer in a diagnostic population compared with film-screen mammography. MATERIALS AND METHODS: From January 2002 to December 2003, 11,621 patients underwent diagnostic mammography at the University of North Carolina Hospital, Chapel Hill. Among these 11,621 patients, 1400 lesions in 1121 patients underwent biopsy. We included the biopsy-performed lesions, so PPV3 was used for comparison of PPVs between film-screen mammography and full-field digital mammography. Six breast radiologists interpreted the images using the Breast Imaging Reporting and Data System of the American College of Radiology. PPV3s were compared between film-screen and full-field digital mammography in the entire study cohort and in specified subgroups according to different radiologists, breast density, and lesion type on mammography. The chi(2) and Fisher's exact tests were used for comparison of PPV3s between two modalities of mammography with the Bonferroni procedure for subgroup analysis. RESULTS: In the entire study cohort, PPV3s of full-field digital mammography and film-screen mammography were similar (difference in PPV3,-0.007; 95% confidence interval, -0.081 to 0.068; P = .8602). In predefined subgroups, there was no difference in PPV3 by the radiologist, breast density, or lesion type between two modalities of mammography (P > .005). CONCLUSION: There is no improvement in PPV for the diagnosis of breast cancer with full-field digital mammography compared with film-screen mammography in a large diagnostic population.