RESUMO
PURPOSE: Conventional orthodontic treatment with stainless steel orthodontic wires may be detrimental to oral health, as it contributes to demineralized lesions and increases adhesion and bacterial biofilm formation, which contributes to cavity development. An alternative that has been investigated to reduce the side effects of orthodontic treatment is the use of coating materials with antimicrobial nanoparticles. This study aims to evaluate the antiadherent and antibacterial properties of TiO2-coated and TiO2:Ag-coated stainless steel orthodontic wires against S. mutans bacteria. METHODS: In the sol-gel method, TiO2:Ag thin films were deposited on stainless steel orthodontic wires. Coated archwires were analyzed for their antibacterial and antiadherent properties. The evaluation of Streptococcus mutans adhesion to the orthodontic wires' surface was conducted according to the type of coating used, biofilm formation assay, and measurement of the pH of the bacterial community. RESULTS: In the microbiological test, the TiO2:Ag coatings revealed a statistically significant difference in terms of microbial adhesion and biofilm formation by Streptococcus mutans. The TiO2:Ag coating on stainless steel wire increased pH levels in the saliva environment. CONCLUSIONS: It can be concluded that antimicrobial orthodontic wires coated with silver TiO2 nanoparticles using the sol-gel thin film are a promising choice for improving orthodontic treatment.
RESUMO
BACKGROUND: The meta-analysis of the data collected in the years 1939-1993 clearly shows an increasing incidence of hypodontia. The disorder is characterized by a congenital absence of deciduous or permanent teeth. It is a significant esthetical and functional problem, which may negatively affect the patient's psychosocial development. OBJECTIVES: The aim of the study was to determine the scale of hypodontia using a sample of Polish orthodontic patients. MATERIAL AND METHODS: The orthopantomograms and medical records of 674 patients aged 6-15 years (376 girls and 298 boys) were analyzed in order to identify dental agenesis. Deciduous and wisdom teeth were excluded from the study. Data regarding gender, the location of the disorder as well as the number and type of missing buds was recorded. RESULTS: Hypodontia was found in 11.6% of the subjects (7.6% girls and 4% boys), more often in the mandible (44.9%) than in the maxilla (28.2%) or in both jaws (26.9%), and these differences were statistically significant (p = 0.096). The occurrence rates of uniand bilateral hypodontia were similar: 51.3% and 48.7%, respectively. The incidence of left-sided hypodontia (37.2%) significantly prevailed over rightsided hypodontia (14.1%) (p < 0.01). Tooth 35 was the most frequently missing one (13.5%). CONCLUSIONS: The large discrepancy in hypodontia prevalence indicates that geographical differences and varying sample sizes greatly affect the results of studies. The literature lacks comprehensive studies regarding hypodontia in Poland. More studies with similar sample sizes and selection criteria need to be carried out. Through an early detection of hypodontia, it is possible to plan comprehensive, interdisciplinary treatment. Regardless of the discrepancies in the literature as to the exact location of the problem, hypodontia affects over 10% of the population of patients treated orthodontically, which justifies the need to study this issue.
