The impact of dental caries and its treatment by conventional or biological approaches on the oral health-related quality of life of children and carers

Background The effect of untreated dental caries and the approaches taken to its treatment have not been extensively elucidated in children. Aim To investigate the impact of untreated dental caries on children aged 4–9 years and whether its treatment with either a conventional or a biological approach influenced the oral health-related quality of life (OHRQoL) of the children and their carers. Design Children (n = 110) and their carers attending two specialist centres for treatment of carious primary teeth completed the Early Childhood Oral Health Impact Scale and the Self-reported Scale of Oral Health Outcomes for 5-year-old Children at baseline prior to dental treatment and at 3–6 months following completion of dental care. Dental treatment was provided using either a conventional or a biological approach. Results Dental caries showed a negative impact on the child and family's OHRQoL (P = 0.001). Children reported difficulty eating (55.5%), sleeping (40%), and avoiding smiling because of how the teeth looked (27.3%). More than half of the parents reported their child had toothache. Parents perceived difficulty eating (40.9%), being irritable (38.2%), and difficulty drinking (30.9%) as being impacts of caries on their child's OHRQoL. In addition, approximately half the parents reported feeling a sense of guilt because of their child's dental disease. Following dental treatment, participants reported significant improvement in their overall health status (P = 0.001). Children's age, gender, or the treatment approach were not statistically significantly associated with changes in OHRQoL of the child or carer. Children and parents who initially reported greater impacts of untreated dental caries demonstrated greater improvements in their overall oral health status (P < 0.0001). Conclusion Dental caries was associated with negative impacts on children and parents' quality of life. Treatment of caries improved the quality of life of children and families significantly, irrespective of whether the treatment was provided by a conventional or a biological approach

Survival of extremophilic yeasts to the stratospheric environment on balloon flights and laboratory simulations

The high-altitude atmosphere is a harsh environment with extremely low temperatures, low pressure, and high UV irradiation. For this reason, it has been proposed as an analogue for Mars, presenting deleterious factors similar to those on the surface of that planet. We evaluated the survival of extremophilic UV-resistant yeasts isolated from a high-elevation area in the Atacama Desert under stratospheric conditions. As biological controls, intrinsically resistant Bacillus subtilis spores were used. Experiments were performed in two independent stratospheric balloon flights and with an environmental simulation chamber. The three following different conditions were evaluated: (i) desiccation, (ii) desiccation plus exposure to stratospheric low pressure and temperature, and (3) desiccation plus exposure to the full stratospheric environment (UV, low pressure, and temperature). Two strains, Naganishia (Cryptococcus) friedmannii 16LV2 and Exophiala sp. strain 15LV1, survived full exposures to the stratosphere in larger numbers than did B. subtilis spores. Holtermanniella watticus (also known as Holtermanniella wattica) 16LV1, however, suffered a substantial loss in viability upon desiccation and did not survive the stratospheric UV exposure. The remarkable resilience of N. friedmannii and Exophiala sp. 15LV1 under the extreme Mars-like conditions of the stratosphere confirms its potential as a eukaryotic model for astrobiology. Additionally, our results with N. friedmannii strengthen the recent hypothesis that yeasts belonging to the Naganishia genus are fit for aerial dispersion, which might account for the observed abundance of this species in high-elevation soils