Hearing loss prevalence and risk factors among older adults in China.

Objective: This study aims to investigate the prevalence of hearing loss, and to analyse the major demographics and risk factors that influence the prevalence in older adults of China.

Design: Cross-sectional investigation.

Study Sample: Probability proportionate to size sampling (PPS) was adopted for this survey.

Effects of folic acid supplementation during different pregnancy periods and relationship with the other primary prevention measures to neural tube defects.

Objective: To find out the prevention effects of folic acid supplements during different pregnancy periods on neural tube defects (NTDs) and the relationship of folic acid supplements with the other NTDs' primary preventive measures.

Methods: A 1:1 case-control study was conducted. Four hundred and fifty-nine women who delivered or gestate infants/fetuses with NTDs in the last two years were randomly selected as cases and were matched with women who delivered babies without obvious birth defects as controls.

Soft tissue image reconstruction using cone-beam computed tomography combined with laser scanning: a novel method to evaluate the masticatory mucosa.

Objective: To construct a 3-D model of the masticatory mucosa to measure the thickness of the facial/lingual gingiva and palatal mucosa.

Study Design: Maxillofacial regions of 8 volunteers were scanned using cone-beam computed tomography to generate 3-D maxillary and mandibular models. Digital models were obtained by laser scanning of the impressions.