The evaluation of the colour changes of traditional composites, ceramic blocks and cad/cam composites in different solutions.

AIMS: The aim of this study is to investigate the color changes of three different traditional composites, one ceramic and two resin-based composites CAD/CAM blocks in different solutions. METHODS: The materials used in the study were CAD/CAM block containing lithium disilicate glass ceramic (Ivoclar), Vita Enamic containing resin (VITA), Lava Ultimate Block containing resin (3M ESPE), G-aenial anterior composite (GC,), Filtek™ Ultimate Universal composite (3M ESPE) and Clearfil Majesty Esthetic composite (Kuaray). As colouring solutions, red wine (Buzbaǧ), black tea (Lipton), coffee (Nescafe) and distilled water (EAU distillee) were used. For the preparation of the traditional composite samples to be used in the study, 7 × 7 mm square-shaped plexiglass moulds, 1.2 mm in thickness, were used. The CAD/CAM blocks with ceramic and resin content were cut at the same thickness using a Struers sensitive cutting device. The samples were then randomly separated into grups of 10 and of the 240 samples, groups were separated into 6 different materials and 4 different solutions. The colour measurements of the 240 samples were taken at baseline, 30 days and 120 days with a Lovibond spectrophotometer (Tintometer). RESULTS: A statistically significant difference was determined between the materials in respect of the ΔE values in the 30-day solution groups (P < 0.05). No statistically significant difference was determined in the ΔE values of the different materials in the 30-day and 120-day distilled water groups (P > 0.05). A statistically significant difference was determined between the materials in respect of the ΔE values in the 120-day solution groups (P < 0.05). CONCLUSION: In respect of discolouration, ceramic blocks are more successful. Resin-based blocks and traditional aesthetic composites showed more discolouration. The dietary habits of the patient should be taken into consideration in the selection of the restorative material.

The evaluation of microleakage and fluoride release of different types of glass ionomer cements.

BACKGROUND: The aim of this study was to evaluate six different glass ionomer cement (GIC)-based restorative materials through comparisons of microleakage and fluoride release. MATERIALS AND METHODS: For microleakage, 30 teeth were randomly separated into 6 groups of 5: Group 1 (Dyract: compomer), Group 2 (Freedom: compomer), Group 3 (Equia: high-viscosity glass ionomer cements), Group 4 (Fuji IX: resin-modified glass ionomer cement), Group 5 (Ketac Molar: traditional glass ionomer cement [TGIC]) and Group 6 (Voco: TGIC). For fluoride release of six different GIC-based restorative materials, standard samples were prepared of 4 mm thickness and 7 mm diameter. A total of 60 samples were obtained as 10 samples from each group. The analyses were made using a Thermo Orion 720 A+ ionometer with the Orion fluoride electrode. At the end of 24 h, 72 h, 7 days, 14 days, and 30 days, the electrode was placed into the dish containing the sample, distilled water, and TISAB II; a reading was taken; and the value shown on the screen was recorded. RESULTS: For microleakage, a statistically significant difference was determined between the groups in respect of the occlusal variable (P < 0.05), no statistically significant gingival variable (P > 0.05). About fluoride release: According to the repeated measures variance analysis results, the difference between the groups, and between the time-group interaction and according to time, was found to be statistically significant (P < 0.05). CONCLUSIONS: In terms of microleakage, it was concluded that all materials could be used in clinical applications. The Equia high-viscosity glass ionomer cements (HVGIC) was determined to be the material with the highest fluoride release value.

The reliability of microleakage studies using dog and bovine primary teeth instead of human primary teeth.

AIM: This was to investigate if dental restorations on human, dog and bovine primary teeth are equitable for microleakage analysis, and the respective marginal adaptation deficiency in in vitro conditions. MATERIALS AND METHODS: In order to determine the level of microleakage in Class V poly acid-modified composite restorations of human, dog and bovine primary teeth, samples were evaluated by dye-leakage method in sections of the inner area of the restorations. RESULTS: We found no leakage in 6 out of 10 (60%) human restorations, in 7 out of 10 (70%) of dog and in 7 out of 10 (70%) of bovine teeth. The levels of dye-microleakage were tested with Kruskal-Wallis one-way variant analysis method. The relative leakage differences were not statistically significant among all species (p>0.05). CONCLUSION: We concluded that dog and bovine primary teeth might be suitable for in vitro studies instead of human ones.

An analysis of the aetiology, prevalence and clinical features of dentine hypersensitivity in a general dental population.

AIM: Dentine hypersensitivity may be defined as pain arising from exposed dentine typically in response to chemical, thermal or osmotic stimuli that cannot be explained as a rising from any other form of dental defect or pathology. The aim to this cross-sectional study was to determine prevalence of dentine hypersensitivity (DH) and to examine some associated etiological factors in a study of patients visiting general dental practitioners in Turkey. PATIENTS AND METHODS: A total of 1368 patients were examined for the presence of cervical dentine hypersensitivity by means of a questionnaire and intraoral tests by (air and probe stimuli). The patients have at least two different quadrants which have sensitive teeth with sound exposed cervical dentin on the facial surface were included the study. RESULTS: A total of 285 teeth were diagnosed as having dentine hypersensitivity in 73 patients, giving an overall prevalence figure for dentine hypersensitivity of 5.3%. 40-49 years age group was the cohort with the greatest number of subjects with DH and females had more predilection than males. Upper premolars were most affected and the commonest initiating factor was cold drinks. Subjects who smoked did not have more sensitive teeth on average than subjects who did not smoke (p > 0.05). Approximately half of the patients reported DH for a duration of within 1-3 days. The commonest etiological factor with the sensitive teeth was the gingival recession. CONCLUSIONS: The prevalence of dentine sensitivity in this sample was lower compared to studies carried out previously in different populations both general practice and hospital clinics. Further larger scale studies are required to assess its prevalence in Turkish population.

Can exposure to manganese and extremely low frequency magnetic fields affect some important elements in the rat teeth?

BACKGROUND: Length and level of exposure to electromagnetic fields (EMFs) is increasing in association with the widespread use of electrical and electronic devices and technological progress. The undesirable effects of extremely low frequency magnetic fields (ELF-MFs) on health have attracted considerable interest. MATERIALS AND METHODS: Sixty-four four-month-old male Wistar rats divided into eight groups of eight rats each were used. Seven groups were exposed to varying dosages of manganese (Mn) and a 50 Hz magnetic field (MF) of approximately 1 mT, while the last group was set aside as the cage control group and not subjected to any procedure. This study was intended to investigate the interactions between the application of MF and Mn and the elements Ca, Zn, Mg, and P thought to be involved in caries, in rat teeth. RESULTS: Levels of Ca, Mg, Zn, and P in the experimental group rats were different to those in the control group. CONCLUSIONS: The results demonstrate that ELF-MF and Mn can have significant effects on levels of elements in rat teeth. Further experimental and epidemiological studies of ELF-MF and Mn are needed in order to evaluate their dental effects.