Self-adhesive resin cements should ease the placement of dental restorations. The purpose of this study was to evaluate their shear bond strength to enamel and dentin. Sixty molars were randomly assigned to 12 test groups (each n = 10), and the approximal surfaces were ground flat to get an enamel and dentin surface with a diameter of at least 4 mm. Ceramic specimens were bonded to the surfaces with either Variolink/Syntac Classic (VSC), Panavia F2.0 (PAF), RelyX Unicem (RLX), Maxcem Elite (MCE), iCem (IC), or an experimental self-adhesive resin cement (EXP). The shear bond strength (crosshead speed: 1 mm/min) was measured after 24-h storage in NaCl (37 degrees C). The fracture modes were determined with a stereomicroscope (magnification, 8-50-fold). VSC had the highest shear bond strength within the enamel groups (42.9 +/- 9 MPa) and IC the lowest (10.5 +/- 4.2 MPa, p < 0.001). The highest dentin shear bond strength was determined for VSC (39.2 +/- 8.9 MPa, p < 0.001) and the lowest for EXP (7.8 +/- 3.9 MPa, p < 0.001). Self-adhesive resin cements fractured mainly between resin and enamel or dentin. The shear bond strength of self-adhesive resin cements was inferior compared to conventional composite resin cements.

The aim of this three-phase prospective study was to determine the effects of a primary-primary prevention program on the oral health of children. Eighty-six pregnant women from various social backgrounds participated in the first phase of this study. In the second phase (at 3 years of age) 54 of the mother-child couples and in the third phase (at 4 years of age) 47 of the mother-child couples remained. Participants were recalled every 6 months and received individual prophylactic care. The following clinical parameters were assessed at each examination period for mother and child: DMF-S or dmf-s, proximal plaque index, and the salivary level of Streptococcus mutans (Dentocult SM). The control group consisted of 65 (at 3 years of age) and 45 (at 4 years of age) children from various kindergartens. All children in the second phase of the study group revealed a naturally healthy dentition with an API of 0-25% and a salivary S. mutans score of 0 (0-10(3) cfu/ml). In the third phase, only four of the 47 children of the study group showed caries, with a mean dmf-s of 1.5. No S. mutans could be detected in 20 (42.6%) children. Ten (21.3%) children of the study group showed a S. mutans score of > or = 2 (> 10(5) cfu/ml). In contrast, only 53 of the 65 children of the control group (second phase) and 26 of the 45 control children (third phase) revealed a naturally healthy dentition. The remaining 19 children of the control group revealed a mean dmf-s of 7.0 at 4 years of age. In the control group, no S. mutans could be detected in 25 (38.5%) children at 3 years of age whereas 21 (32.3%) children showed a S. mutans score of > or = 2. In the third phase, a salivary S. mutans score of > or = 2 was found in 27 (60%) children of the control group. The statistical comparison between the study and the control groups revealed significant differences for all results determined (P < 0.001). Additionally, all mothers revealed a significant improvement in oral health and a reduction of salivary S. mutans colonization. From our data we conclude that a pre- and postnatal prevention program (primary-primary vs primary prevention) may significantly improve the oral health of mother and child.

Prevention programs starting during pregnancy may establish an improved health behavior. Caries, periodontitis, and dietary complications in mother and child can be avoided by improving maternal oral health and by a tooth-friendly diet.

SUMMARYThis study evaluated the shear bond strength of self-etch adhesives to enamel and the effect of additional phosphoric acid etching.Seventy sound human molars were randomly divided into three test groups and one control group. The enamel surfaces of the control group (n=10) were treated with Syntac Classic (SC). Each test group was subdivided into two groups (each n=10). In half of each test group, ground enamel surfaces were coated with the self-etch adhesives AdheSe (ADH), Xeno III (XE) or Futurabond NR (FNR). In the remaining half of each test group, an additional phosphoric acid etching of the enamel surface was performed prior to applying the adhesives. The shear bond strength was measured with a universal testing machine at a crosshead speed of 1 mm/minute after storing the samples in distilled water at 37°C for 24 hours. Fracture modes were determined by SEM examination. For statistical analy-© Operative Dentistry, 2008, 33-2, 155-162 Clinical RelevanceWhen using self-etch adhesives to bond composite materials to enamel, there is concern about the ability to achieve bond strengths comparable to approved etch-and-rinse systems. An additional phosphoric acid etching can improve the shear bond strength of self-etch adhesives to enamel.

Various in vivo and in vitro investigations have indicated that tobacco smoking as well as the use of smokeless tobacco products may be important risk factors for the development and severity of inflammatory periodontal disease. The purpose of this study was to determine the cytotoxicity of nicotine by means of human primary oral fibroblast cultures and a permanent cell line. The cytotoxicity of nicotine was evaluated by determination of cell growth, cell membrane integrity, protein content, and alterations of the cytoskeleton. Furthermore, recovery following nicotine exposure was assessed by vital staining (trypan blue). Dose-dependent toxic effects of nicotine were measured within a range of 0.48 mM to 62 mM. Growth of fibroblasts was decreased by nicotine concentrations higher than 7.8 mM. Additionally, the protein content was significantly decreased and cell membranes were damaged. Morphological alterations of microtubules and vimentin filaments were observed at concentrations higher than 3.9 mM. Nicotine-exposed cells revealed atypical shapes and vacuoles. The toxic effects of nicotine became irreversible in the range between 10.5 and 15.5 mM, whereas at lower concentrations cells recovered after the withdrawal of nicotine. Our results confirm clinical oberservations regarding the important role of nicotine as a risk factor in the etiology and progression of periodontal disease.