Ion Release and Surface Changes of Nickel-Titanium Archwires Induced by Changes in the pH Value of the Saliva-Significance for Human Health Risk Assessment.

The aim of this study was to explore whether changes in the salivary pH influence mechanical properties, surface roughness, and ion release from NiTi archwires with various surface coatings, and discuss the clinical significance of the findings. The uncoated, rhodium-coated, and nitrified NiTi wires were immersed into artificial saliva of different pH values (4.8, 5.1, 5.5, and 6.6). Released nickel and titanium ions were measured with inductively coupled plasma-optical emission spectroscopy at the end of 28 days. Atomic force microscopy was used to measure the arithmetic average surface roughness Ra, the root-mean-square roughness Rq, and the maximum height of the asperities RZ. The nanoindentation hardness (HIT) and Young's modulus (EIT) measurements were performed. The change in the pH of artificial saliva is inversely proportional to the release of titanium from both coated and uncoated wires, and the release of nickel from uncoated wires. The surface roughness parameters of both coated and uncoated wires are unaffected by the change in the pH of artificial saliva. The change in the pH of saliva has minor influence on the hardness and Young's modulus of elasticity of both coated and uncoated wires. The concentration of released metal ions measured was below the recommended upper limit for daily intake; nevertheless, hypersensitivity effects cannot be excluded, even at lower concentrations and at low pH.

Correlation between the DAI and ICON Indices used for Assessment of Orthodontic Treatment need in Croatian Schoolchildren.

INTRODUCTION: The aims were: evaluation of the correlation between the Dental Aesthetic Index (DAI) and Index of Complexity, Outcome and Need (ICON); the assessment of orthodontic treatment need for schoolchildren in a population with two indices, separately for schoolchildren with mixed and permanent dentition; the estimation of the population share that could not receive orthodontic treatment because of the presence of caries and/or gingivitis. METHODS: A total of 2652 Zagreb school children (7 - 19 years old, 52.4% of them were females) completed a questionnaire regarding previous orthodontic treatment and the type of appliance used. Their oral cavity was also inspected. The DAI and ICON indices were used for the assessment of malocclusion prevalence. RESULTS: The subjects with mixed dentition had a greater need for orthodontic treatment, when compared to subjects with permanent dentition, when using the DAI index (p<0.001). When using the ICON index, 11.7% of subjects with mixed dentition had very severe malocclusion, as opposed to 5.8% of subjects with permanent dentition. The DAI and ICON scores correlated positively linearly (r=0.521; p<0.001). A higher prevalence of both gingivitis and caries was recorded more often in boys; caries more often in the group with the mixed dentition, and gingivitis in the group with permanent dentition (p<0.05). CONCLUSION: The DAI and ICON indices have moderate agreement in assessment of malocclusion severity scores. One third of all schoolchildren with various degrees of both ICON and DAI indices have gingivitis, and half of them have caries.

History of Orthodontic Treatment, Treatment Needs and Influencing Factors in Adolescents in Croatia.

AIM: The aim of this study was to assess the orthodontic treatment needs of adolescents in Zagreb, Croatia, in relation to their orthodontic treatment history, caries experience and socio-demographic parameters. METHODS: The study sample comprised 1,289 adolescents from 12 randomly selected public schools in Zagreb, Croatia. The subjects were 15-18 years old (mean age 16.3±1.4), and 51% of them were girls. The Dental Aesthetic Index (DAI), the sum of the numbers of decayed, missing and filled teeth (DMFT index), and a questionnaire (covering socio-demographic issues, oral health-related attitudes and behaviours) were employed in this study. The data was analyzed by means of Chi-square test, analysis of variance, and multiple logistic regression models. RESULTS: The DMFT score was higher in adolescents with no orthodontic history (5.2±3.7) than in those who were under orthodontic treatment at the time of the research (4.5±3.2; p=0.043). More than 60% of the adolescents have never undergone any orthodontic treatment, around 24% previously undergone treatment and 15% were under treatment at the time of the research. Overall, 85% of the adolescents' orthodontic appliances were removable, and the girls were more often under orthodontic treatment. One fifth of the studied population had severe or very severe malocclusion. Adolescents with previous orthodontic treatment were more often interested in better teeth alignment, changes in their teeth positioning and continuing orthodontic treatment. Multiple logistic regression model demonstrated that previously treated adolescents, in comparison with their untreated peers, were on average older (p=0.002), were less satisfied with the appearance of their teeth (p=0.001), they had higher malocclusion severity (p=0.046), and fewer dental caries (p<0.001), changed toothbrushes more often (p=0.012), and their mothers attained higher education (p<0.001). CONCLUSIONS: Although many adolescents received orthodontic treatment, the severity of their malocclusion was still somewhat high, and they were more often dissatisfied with their treatment outcome. Mothers' educational level was found to be the most important socio-demographic predictor for children's involvement in orthodontic treatment. The caries experience increased in comparison with the Croatian national survey data from 1999.

Feedback of Individual Genetic Results to Research Participants: Is It Feasible in Europe?

BACKGROUND: There is growing consensus that individual genetic research results that are scientifically robust, analytically valid, and clinically actionable should be offered to research participants. However, the general practice in European research projects is that results are usually not provided to research participants for many reasons. This article reports on the views of European experts and scholars who are members of the European COST Action CHIP ME IS1303 (Citizen's Health through public-private Initiatives: Public health, Market and Ethical perspectives) regarding challenges to the feedback of individual genetic results to research participants in Europe and potential strategies to address these challenges. MATERIALS AND METHODS: A consultation of the COST Action members was conducted through an email survey and a workshop. The results from the consultation were analyzed following a conventional content analysis approach. RESULTS: Legal frameworks, professional guidelines, and financial, organizational, and human resources to support the feedback of results are largely missing in Europe. Necessary steps to facilitate the feedback process include clarifying legal requirements to the feedback of results, developing harmonized European best practices, promoting interdisciplinary and cross-institutional collaboration, designing educational programs and cost-efficient IT-based platforms, involving research ethics committees, and documenting the health benefits and risks of the feedback process. CONCLUSIONS: Coordinated efforts at pan-European level are needed to enable equitable, scientifically sound, and socially robust feedback of results to research participants.