Open-mouth posture and maxillary arch width in young children: a three-year evaluation.

A large biracial sample of children were assessed for open mouth posture and maxillary arch width once a year for 3 years. Analyses revealed that although the youngsters exhibited open-mouth posture at high levels, over time, there was a significant decrease in this behavior. Racial and gender differences, as well as a race-by-time interaction, were also evidenced. The children displayed a significant increase in maxillary arch width across time, with gender and racial differences seen in this growth pattern. Finally, when the youngsters were classified as exhibiting primarily open-mouth or closed-mouth posture, it was observed that children with open-mouth posture displayed a significantly slower pattern of maxillary growth compared with children who display anterior lip seal posture. The implications of the findings were discussed.

A longitudinal evaluation of open mouth posture and maxillary arch width in children.

Open mouth posture and maxillary arch width were assessed annually for 4 years in a group of children. While younger children exhibited high levels of open mouth posture, this behavior decreased significantly over time. Racial and sex differences, as well as a race-by-time interaction were also evident. The children displayed a significant increase in maxillary arch width across time with sex and racial differences in this growth pattern. Subjects were classified as exhibiting primarily open mouth or closed mouth posture. Although both groups showed increased maxillary arch widths over time, the closed mouth subjects showed significantly greater maxillary arch growth.

Open mouth posture and cross-sectional nasal area in young children.

A biracial sample of two-hundred ninety-six children were assessed for open-mouth posture (OMP) in the natural environment. In addition, rhinometry was performed on 288 of the youngsters. Means were computed for percent OMP and cross-sectional nasal airway. Results indicated that in general these children exhibited relatively high rates of OMP. Boys displayed significantly greater OMP than girls. However, children exhibiting OMP on 80% of the observation intervals had significantly smaller cross-sectional nasal areas than the youngsters who displayed OMP on fewer than 20% of observation intervals. The implications of the findings were discussed.

Rhinometry and open-mouth posture in young children.

A biracial sample of 348 elementary school children who were in the first grade were assessed for open-mouth posture (OMP) in the natural environment. In addition, rhinometry was performed on 296 of the children. Means were computed for percent OMP and cross-sectional nasal airway. Results indicated that, in general, these children exhibited relatively high rates of OMP. Boys displayed significantly greater OMP than girls, and black children showed significantly larger cross-sectional nasal areas than white children. A significant correlation between OMP and nasal area only was evident for children exhibiting OMP during more than 80% of the observation intervals. The implications of the findings were discussed.

Myofunctional and dentofacial relationships in second grade children.

One hundred and thirty-three second graders in rural public school were assessed on a number of dental, skeletal, and oral muscle function measures. Correlational analyses were conducted in order to determine whether specific myofunctional variables were associated with dentofacial development. Significant relationships were observed between open mouth posture and a narrow maxillary arch and long facial height. Labial and lingual rest and swallow patterns were also related to poor coordination of lip and tongue movements.

Microbial indicators of oil-rich salt marsh sediments.

Selected microbial parameters were monitored in sediments from a pristine and an oil-field salt marsh. Although numbers of hydrocarbonoclastic bacteria and fungi were significantly greater in the oil field, the values did not show a strong correlation with levels of hydrocarbons (r = 0.43 and r = 0.49, respectively). However, a high correlation was noted between ratios of hydrocarbonoclastic and total aerobic heterotrophic bacteria and levels of hydrocarbons as well as the relative concentration of hydrocarbons (ratio of hydrocarbons to chloroform extractables) (r = 0.87 and r = 0.77, respectively). Data suggest that this first ratio is a more valid microbial indicator of hydrocarbon abundance than other factors examined. Significant differences in the ratio of pigmented to total colony-forming units, the ratio of different to total colony-forming units, and the diversity index were noted between the natural and oil-field marsh. It is suggested that the presence of hydrocarbons alters the relative abundance of the most predominant aerobic heterotrophic bacteria.