RESUMEN
Objective@#To explore the relationship between lifestyle and myopia and construct Nomogram model to predict myopia risk among primary school students in Tianjin, so as to provide a scientific basis for precision myopia prevention and control.@*Methods@#From April to July of 2022, a census method was used to conduct vision testing and lifestyle related questionnaires among 373 180 primary school students in 15 districts of Tianjin. The relationship between lifestyle and myopia was analyzed by the multivariate Logistic regression, and a nomogram prediction model was constructed to predict myopia risk.@*Results@#The detection rate of myopia among primary school students in Tianjin was 37.6%. The results of the multivariate Logistic regression showed that daily outdoor activity time of 1-2 h ( OR =0.94) and >2 h ( OR =0.84), time of using daily electronic devices of >2 h ( OR =1.03), daily paper materials reading and writing time of 1-2 h ( OR =1.02) and >2 h ( OR =1.09), weekly fresh vegetable intake of 2-6 times ( OR =0.93) and ≥7 times ( OR =0.88) were statistically correlated with myopia ( P <0.01). The Nomogram prediction model showed that the factors associated with myopia were grade, family history of myopia, gender, daily outdoor activity time, weekly frequency of fresh vegetable intake, daily paper materials reading and writing time, and time of using daily electronic devices time.@*Conclusions@#The lifestyle of primary school students in Tianjin is associated with myopia. The constructed nomogram model could provide a scientific basis for identifying key intervention populations for myopia prevention and taking targeted prevention and control measures.
RESUMEN
The aims of the present study were to describe an impression method of "inner circular sealing area" and to evaluate the effect of the method on retention, aesthetics and comfort of complete dentures, which lack labial base for patients with maxillary protrusions. Three patients were subjected to the experiment, and two sets of complete maxillary dentures were made for each patient; the first set was made without labial base via an inner circular sealing area method (experimental group) and the second had an intact base that was made with conventional methods (control group). Retention force tests were implemented with a tensile strength assessment device to assess the retention and a visual analogue scale (VAS) was used to evaluate the comfort between the two groups. Results showed larger retention force, better aesthetics and more comfort in the experimental group. The improved two-step impression method formed an inner circular sealing area that prevented damage to the peripheral border seal effect of the denture caused by incomplete bases and obtained better denture retention.
O objetivo deste caso foi descrever um método de impressão por "área de selamento circular interno" e avaliar o efeito deste método na retenção, estética e conforto de próteses totais sem base labial para pacientes com protrusão maxilar. Três pacientes foram objeto desta experiência e foram feitas duas próteses maxilares completas para cada um deles; a primeira foi elaborada sem base labial pelo método de área de selamento circular interno (grupo experimental) e a outra teve uma base feita pelo método convencional (grupo controle). Foram realizados testes de retenção com estudo de tensão para avaliar a retenção e para avaliação do conforto dos dois grupos, foi empregada a escala analógica visual (EAV). Os resultados demonstraram que o grupo experimental apresentou força de retenção maior, estética melhor e mais conforto. O método modificado de impressão em duas etapas formou uma área de selamento circular interno que evitou danos ao selamento periférico causados por bases incompletas e obteve melhor retenção da prótese.