Phrenic nerve stimulation (PNS) can assess airflow dynamics of the upper airway (UA) during wakefulness in man. Using PNS, we aimed to assess the impact of neck flexion and mouth opening in promoting UA unstability. Measurements were made during nasal breathing in seven healthy subjects (ages = 23-39 yr; one woman). Surface diaphragm electromyogram, esophageal pressure referenced to mask pressu...

This study examined the effect of mouth breathing on the strength and duration of vertical effect on the posterior teeth using related functional parameters during 3 min of gum chewing in 39 nasal breathers. A CO(2) sensor was placed over the mouth to detect expiratory airflow. When no airflow was detected from the mouth throughout the recording period, the subject was considered a nasal breath...

Objective: To examine changes in reports of common cold symptoms and mouth ulcers following smoking cessation. It was hypothesised that reports of these symptoms would increase on stopping smoking. Design: Smokers were assessed one week before stopping smoking (baseline), then after one, two, and six weeks of smoking abstinence. Participants: 174 smokers attending a seven week smoking cessation...

Mouth-exhaled hydrogen cyanide (HCN) concentrations have previously been reported to originate from the oral cavity. However, a direct correlation between the HCN concentration in oral fluid and in mouth-exhaled breath has not been explicitly shown. In this study, we set up a new methodology to simultaneously measure HCN in the headspace of oral fluid and in mouth-exhaled breath. Our results sh...

OBJECTIVE To investigate the relationship between excursion of the diaphragm muscle and spinal curvatures in mouth breathing children. METHODS A total of 52 children of both sexes, aged from 5 to 12 years, were studied. After otorhinolaryngological assessment, the children were divided into two groups: mouth breathers and nose breathers. All of the children underwent videofluoroscopic examina...

OBJECTIVE To assess the knowledge and attitudes of local primary health care physicians in relation to cardiopulmonary resuscitation (CPR) and defibrillation. METHODS We conducted a survey on general practitioners in Singapore by using a self-administered questionnaire that comprised 29 questions. RESULTS The response rate was 80%, with 60 of 75 physicians completing the questionnaire. The ...

To investigate dental erosion in employees working with sulfuric acid at a lead storage battery manufacturing plant and level of personal exposure to sulfuric ions, we measured sulfuric ion concentrations in the mouth rinse of those employees. We also measured exposure levels from air samples obtained from 2 employees from the same plant who did not work with sulfuric acid using a portable air ...

OBJECTIVE This study compares the effects of three different mouth rinses with respect to reducing Streptococcus mutans (S. mutans) colony counts on the teeth and tongue surfaces. MATERIALS AND METHODS In this study, comparison tests using the alcohol-free 0.1% chlorhexidine mouth rinse, alcohol-containing essential oil mouth rinse, and alcohol-free essential oil-containing mouth rinse were c...

OBJECTIVE The primary objective of this study was to compare the effectiveness of a water flosser plus sonic toothbrush to a sonic toothbrush alone on the reduction of bleeding, gingivitis, and plaque. The secondary objective was to compare the effectiveness of different sonic toothbrushes on bleeding, gingivitis, and plaque. METHODS One-hundred and thirty-nine subjects completed this randomi...

BACKGROUND Nose and mouth leaks impair effective pressure transmission during neonatal continuous positive airway pressure (CPAP), but little is known about how these leaks affect physiological parameters. This study investigated the influence of nose leaks and spontaneous mouth opening on peripheral oxygen saturation (SpO₂) and respiratory rate (RR) using nasopharyngeal CPAP. METHODS In 32 n...