Examination of Climate and Environmental Factors in a Dental Hospital by Cluster Analysis and Partial Correlation Analysis

Abstract

To identify dental hospital climate and environmental problems, the temperature, humidity, air flow, number of persons, opened windows, and outlets of functional air-conditioner were measured for 2 years in orthodontics, pedodontics, restoration, and prosthetics clinics at Asahi University dental hospital. Analytical points were as follows: 1. chronological changes caused by the clinic climatic and environmental factors, 2. classification of the clinics according to climatic and environmental factors by cluster analysis, and 3, the degree of influence of emvironmental factors on the clinic climate by partial correlation analysis.
The following conclusions were obtained.
1. Temperature was 17.1-27.2°C, humidity was 38.4-73.9%, and air flow was 0.09-0.31m/sec. in middle-sized clinics, and these factors were 19.6-28.3°C, 22.9-60.6%, and 0.09-0.31m/sec. in large clinics.
2. Humidity was high when the conditioner was not operating, but was low in winter because of excessive heating with the air-conditioner.
3. Four dental clinics were classified into two groups by cluster analysis. Cluster analysis is a useful method for classifying the dental clinics by climatic and environmental factors.
4. By partial correlation analysis, we found that varying climate and emvironmental facters affected the clinic climate.
As a result, we suggest that operating the air-conditioner in all seasons is necessary in order to obtain amenable conditions in dental clinics.