BackgroundGiven the prevalence of malocclusions and the impact they have on oral health, patients’ quality of life assessments provide useful information, not only in terms of patients’ needs and expectations before treatment, but about whether or not orthodontic treatments meet them satisfactorily. The present systematic review was carried out to evaluate changes in the quality of life of adolescent patients after orthodontic treatment.Material and MethodsAn electronic search was conducted in the Pubmed, Embase, Cochrane and Scopus databases. The review followed PRISMA guidelines for systematic reviews and meta-analyses.ResultsOf the 817 studies identified in the initial search, only 10 met the inclusion criteria. In relation to the instrument used to assess oral health-related quality of life (OHRQoL), half the studies used the oral health impact profile-14 (OHIP-14) and the other half the child perceptions questionnaire (CPQ 11-14). All the studies, with the exception of Benson et al., reported a significant improvement in OHRQoL at the end of treatment.ConclusionsThere is a positive association between OHRQoL and orthodontic treatment in adolescent patients. Key words:Quality of life, life quality, oral health related quality of life, QoL, OHRQoL, orthodontic treatment, adolescents, teenagers.

Background and Objectives: Nanotechnology has become a significant area of research focused mainly on increasing the antibacterial and mechanical properties of dental materials. The aim of the present systematic review and meta-analysis was to examine and quantitatively analyze the current evidence for the addition of different nanoparticles into dental restorative materials, to determine whether their incorporation increases the antibacterial/antimicrobial properties of the materials. Materials and Methods: A literature search was performed in the Pubmed, Scopus, and Embase databases, up to December 2018, following PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analysis) guidelines for systematic reviews and meta-analyses. Results: A total of 624 papers were identified in the initial search. After screening the texts and applying inclusion criteria, only 11 of these were selected for quantitative analysis. The incorporation of nanoparticles led to a significant increase (p-value < 0.01) in the antibacterial capacity of all the dental materials synthesized in comparison with control materials. Conclusions: The incorporation of nanoparticles into dental restorative materials was a favorable option; the antibacterial activity of nanoparticle-modified dental materials was significantly higher compared with the original unmodified materials, TiO2 nanoparticles providing the greatest benefits. However, the high heterogeneity among the articles reviewed points to the need for further research and the application of standardized research protocols.