The effect of age and abstinence time on semen quality: a retrospective study / 亚洲男科学杂志(英文版)

This study analyzed the effects of male age and abstinence time on semen quality and explored the best abstinence time for Chinese males among different age groups. Semen parameters, including sperm kinetics, morphology, and DNA fragmentation index (DFI), were reviewed from 2952 men. Samples were divided into six age groups (≤25 years, 26-30 years, 31-35 years, 36-40 years, 41-45 years, and >45 years) and were divided into six groups according to different abstinence time (2 days, 3 days, 4 days, 5 days, 6 days, and 7 days). The differences in semen quality between the groups were compared, and the effect of age and abstinence time on semen quality was analyzed. Significant differences were observed in semen volume, progressive motility (PR), and DFI among the age groups (all P < 0.05), and no significant differences were observed in sperm morphological parameters (all P > 0.05). There were significant differences in semen volume, PR, and DFI among different abstinence time groups (all P < 0.05) and no significant differences in sperm morphological parameters (all P > 0.05). Pearson analysis showed that male age and abstinence time were both significantly correlated with sperm kinetics and DFI (both P < 0.05), while no significant correlation was found with sperm morphological parameters (all P > 0.05). The box plots and histograms of men's age, abstinence time, and semen quality show that most semen quality parameters differ significantly between the 2 days and 7 days abstinence groups and other groups at different ages. Except for the sperm morphology parameters, sperm kinetic parameters and sperm DFI are linearly related to male age and abstinence time.

Clinical study of complete dentures supported by two endosteal magnetic-attachment implants / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To evaluate treatment outcomes of mandibular complete denture supported by two endosteal magnetic-attachment implants in edentulous patients with severe mandibular alveolar ridge absorption.</p><p><b>METHODS</b>Eight edentulous patients with severe mandibular alveolar ridge absorption were chosen. Each of them was treated with a complete denture supported by two CDIC implants. The implants were inserted at the areas of two the first premolars respectively. After five months, two magnets were adhered to the inside of the complete dentures. Retention, masticatory efficiency and maximal masticatory force were measured before and after the magnets were adhered and six months later.</p><p><b>RESULTS</b>Statistical analysis revealed that retention, masticatory efficiency and maximal masticatory force were all increased after the magnets were adhered (P < 0.01) and six months later (P < 0.01).</p><p><b>CONCLUSION</b>Retention, maximal masticatory force and masticatory efficiency were significantly increased after the endosteal magnetic attachment implants were applied. It is concluded that mandibular complete denture supported by two endosteal magnetic attachment implants is an effective method for severe alveolar ridge absorption cases.</p>