In 2007, new clinical criteria were approved by the FDI World Dental Federation and simultaneously published in three dental journals. The criteria were categorized into three groups: esthetic parameters (four criteria), functional parameters (six criteria) and biological parameters (six criteria). Each criterion can be expressed with five scores, three for acceptable and two for non-acceptable (one for reparable and one for replacement). The criteria have been used in several clinical studies since 2007, and the resulting experience in their application has led to a requirement to modify some of the criteria and scores. The two major alterations involve staining and approximal contacts. As staining of the margins and the surface has different causes, both phenomena do not appear simultaneously. Thus, staining has been differentiated into marginal staining and surface staining. The approximal contact now appears under the name "approximal anatomic form" as the approximal contour is a specific, often non-esthetic issue that cannot be integrated into the criterion "esthetic anatomical form". In 2008, a web-based training and calibration tool called e-calib ( www.e-calib.info ) was made available. Clinical investigators and other research workers can train and calibrate themselves interactively by assessing clinical cases of posterior restorations which are presented as high-quality pictures. Currently, about 300 clinical cases are included in the database which is regularly updated. Training for eight of the 16 clinical criteria is available in the program: "Surface lustre"; "Staining (surface, margins)"; "Color match and translucency"; Esthetic anatomical form"; "Fracture of material and retention"; "Marginal adaptation"; "Recurrence of caries, erosion, abfraction"; and "Tooth integrity (enamel cracks, tooth fractures)". Typical clinical cases are presented for each of these eight criteria and their corresponding five scores.

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The objective of this study was to assess the bonding performance of a new universal self-adhesive cement RelyX Unicem (RXU) to dentin and enamel compared to four currently used luting systems, using a shear bond strength test with and without thermocycling. Median bond strengths were determined after 24 h storage, and after thermocycling (6,000 cycles, 5-55 degrees C) for RXU and compared to Syntac/Variolink II (SynC/V) as a standard for luting conventional ceramics, ED-Primer II/Panavia F2.0 (EDII/PF2), Prime and Bond NT/Dyract Cem Plus (PBNT/DyCP), and a glass ionomer cement, Ketac Cem (KetC), as a standard for luting high-strength ceramic and metal-based restorations. Data (n=10 per group) were statistically analyzed using the Mann-Whitney-Wilcoxon test at the 0.05 level of significance. The bond strength (MPa) of RXU to dentin (10.8) was not statistically different from those of SynC/V (15.1), EDII/PF2 (10.5) or PBNT/DyCP (10.1), and statistically higher than KetC (4.1). The bond strength of RXU to enamel (14.5) was significantly lower than those of SynC/V (32.8), EDII/PF2 (23.6), and PBNT/DyCP (17.8), but higher than KetC (6.1). After thermocycling, the bond strength of RXU to enamel significantly decreased, but was still significantly higher than that of KetC. RelyX Unicem may be considered an alternative to Ketac Cem for high-strength ceramic or metal-based restorations, and may be used for luting conventional ceramic crowns with little or no enamel left.

The purpose of this study was to collect information on the main causes of tooth loss in the western states of Germany as perceived by dentists and their patients. Sixty-eight dentists, out of 80 that were selected with a systematic random method for an epidemiological study in the western states of Germany, recorded their reason for tooth extraction. Included in the study were only extractions of permanent teeth during a period of 2 weeks (March 1990), up to a maximum of 20 patients per dentist. Of 926 returned questionnaires, 882 could be evaluated. In all 1215 teeth in 882 patients were extracted. The extraction of third molars was included as a reason, when caries, periodontal reasons and others were not indicated. Caries was the reason given for 20.7% of all extractions; periodontal diseases for 27.3%; caries and periodontal reasons for 18.7%; third molars for 14.7%; prosthetic reasons for 11.2%; orthodontic reasons for 4.1%; trauma for 0.4% and others for 2.9%. While caries is a major reason in all age groups, periodontal diseases and the combination of caries and periodontal reasons are more frequent than all other reasons for the age groups beyond 40 or 45 yr, respectively. The third molar was the most often extracted tooth. The patients were asked for their main reason for tooth extraction. For the patients, pain was the major reason for extraction (47.2%). According to the participating dentists periodontal disease is the most frequent cause of tooth extraction for people over 40 yr of age, while for those below 40 yr of age, caries and third molar extractions are the most frequent reasons.

Background: Millions of people are tattooed. However, the frequency of health problems is unknown. Methods: We performed an Internet survey in German-speaking countries. Results: The provenance of tattooed participants (n = 3,411) was evenly distributed in Germany. The participants had many (28%; >4) and large tattoos (36%; ≧900 cm²). After tattooing, the people described skin problems (67.5%) or systemic reactions (6.6%). Four weeks after tattooing, 9% still had health problems. Six percent reported persistent health problems due to the tattoo, of which females (7.3%) were more frequently concerned than males (4.2%). Colored tattoos provoked more short-term skin (p = 0.003) or systemic (p = 0.0001) reactions than black tattoos. Also the size of tattoos and the age at the time of tattooing play a significant role in many health problems. Conclusions: Our results show that millions of people in the Western world supposedly have transient or persisting health problems after tattooing. Owing to the large number and size of the tattoos, tattooists inject several grams of tattoo colorants into the skin, which partly spread in the human body and stay for a lifetime. The latter might cause additional health problems in the long term.