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Results indicate that tested orthodontic bonding composites are suitable for clinical application, but that further studies using different test methods are needed for Transbond XT.

) were prepared and the samples were extracted in 3 mL of Basal Medium Eagle with 10% newborn calf serum for 24 hours. The L929 cells were plated (25,000 cells/mL) in wells of 96-well dishes and maintained in a humidified incubator for 24 hours at 37uC, 5% CO 2 , and 95% air. After 24-hour incubation of the cells, the incubation medium was replaced by the immersed medium in which the samples were stored. Then L929 cells were incubated in contact with eluates for 24 hours. The cell mitochondrial activity was evaluated by the methyltetrazolium test. Twelve wells were used for each specimen, and methyltetrazolium tests were applied two times. The data were statistically analyzed using one-way analysis of variance and Tukey Honestly Significantly Different tests. Results:Results with L929 fibroblasts demonstrated that all freshly prepared resin-modified orthodontic band adhesive materials reduced vital cell numbers (P . .05), in comparison to the control group. Our data demonstrate that all materials showed significant cytotoxicity compared to the control group. Conclusions:The results indicate that all materials showed significant cytotoxicity compared to the control group, and further studies using different test methods are needed for all resin-modified orthodontic band adhesives. (Angle Orthod. 2010;80:890-895.)

Objective: To test the null hypothesis that there is no difference between the effects of fan-type rapid (FRME) and rapid maxillary expansion (RME) used with an acrylic bonded expansion appliance on dentofacial structures in early occlusal stages. Materials and Methods: This was a prospective clinical trial. The FRME group had an anterior constricted maxillary width with a normal intermolar width, and the RME group had bilateral constricted maxillary width. The FRME group consisted of 20 patients (mean age, 8.96 6 1.19 years), and the RME group consisted of 22 patients (mean age, 8.69 6 0.66 years). Lateral and frontal cephalometric radiographs and dental casts were taken before and after expansion and 3 months after completing treatment for each patient. The data were compared using repeated-measures analysis of variance. The paired-samples t-test was used to evaluate treatment and retention effects, and the independent samples t-test was used to consider the differences between the two groups. Results: The maxilla moved downward and forward in both groups. The nasal cavity and maxillary width were expanded more in the RME group, and there were only a few relapses in this group during the retention period. There was significant labial tipping of the upper incisors in the FRME expansion group. The expansion of intercanine width was similar in both groups, but the expansion of intermolar width was significantly greater in the RME group. Conclusion: The null hypothesis was rejected. There was a difference between the effects of FRME and RME used with an acrylic bonded expansion appliance on dentofacial structures in the early occlusal stages. (Angle Orthod. 2013;83:842-850.)

IntroductionOrthodontics is a unique science in dentistry since its workspace sets on the external surface of enamel when using fixed appliances for treatment. Orthodontists or patients may encounter unwanted changes on the enamel surface or structure, such as discoloration, white spots, microcracks, fractures, and abrasions during and after fixed orthodontic treatment (FOT) because of, e.g., diet, oral care, bonding materials and techniques, composites, appliances, debonding, and clean-up procedures (1-3). Bonding materials and composites of FOT are the most prominent factors responsible for enamel color alterations (3,4). Enamel discolorations may occur by direct absorption of food colorants and products arising from the corrosion of the orthodontic appliance into resin tags (5,6). The long-term presence of these residues in the enamel tags during fixed treatment makes the color stability of these materials critical for tooth color (7).A great deal of orthodontic research has concentrated on the assessment of the physical and mechanical performances of the adhesive resins. However, comparatively few studies have investigated the effects of bonding materials used in brackets on enamel color (3,5,8-10) and only 2 clinical studies examined the color alterations of teeth associated with FOT (3,4). According to the findings of those studies, visible enamel color changes may occur with fixed appliances, which would be detected in clinical trials (3,4). Although enamel color was changed after orthodontic treatment, the lightcured composite was associated with lower discoloration rates than chemically cured resins (4). According to Karamouzos et al. (4), orthodontists may choose the use of no-mix and light-cured composites, whose effects on enamel color were the same. However, a recent in vitro study about discoloration of these types of orthodontic composites revealed that unsatisfactory color stability was Background/aim: To determine the color alterations of natural teeth associated with different orthodontic composites used in comprehensive short-term treatment.Materials and methods: Twenty-two patients were treated with fixed appliances and 22 untreated subjects were also evaluated. Lower incisors were bonded with different orthodontic composites: 42 with Grengloo, 41 with Light Bond, 31 with Kurasper F, and 32 with Transbond XT. The color parameters of the Commission Internationale de l'Eclairage (CIE) were measured for each tooth with a spectrophotometer. Color assessment in relation to time, adhesive material, and their interaction was made with 2-way mixed analysis of variance (ANOVA) and 1-way ANOVA for the color differences (∆E*). Further analyses were done using Tukey's honestly significant difference tests and paired-samples t-tests. Results:The color of teeth was affected by treatment. The mean L* and a* values increased, whereas the mean b* values decreased. Total color differences of teeth demonstrated visible color changes clinically after treatment, ranging from 1.12 to 3.34 ∆E units. However, there w...

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BackgroundThe aim of this study was to evaluate the effects of long and short term systemic usage of royal jelly on bone formation in the expanded maxillary suture in a rat model.Material and MethodsTwenty eight Wistar albino rats were randomly divided into 4 equal groups: Control (C); Only Expansion (OE), Royal Jelly (RJ) group, Royal Jelly was given to rats by oral gavage only during the expansion and retention period; Royal Jelly plus Nursery (RJN) group, Royal Jelly was given to rats by oral gavage during their nursery phase of 40 days and during the retention period. After the 5 day expansion period was completed, the rats underwent 12 days of mechanical retention. All rats were sacrificed in same time. Histological examination was performed to determine the number of osteoclasts, number of osteoblasts, number of capillaries, inflammatory cell infiltration, and new bone formation.ResultsNew bone formation, number of osteoclasts, number of osteoblasts, and the number of capillaries in the expanded maxillary sutures were higher in the RJ and RJN groups than in the other groups. Statistical analysis also demonstrated that new bone formation and the number of osteoblasts was also highest in the RJN group.ConclusionsThe systemic administration of Royal Jelly in conjunction with rapid maxillary expansion may increase the quality of regenerated bone. Key words:Bone formation, rapid maxillary expansion, Royal jelly.