lya, van't Hof & Konig, 1997). Some earlier work has not only noted that there is a connection but has attempted to explore its nature (e.g., Milsom, Woodward, Haran & Lennon, 1996).
The original research study selected from references provided in the review article consists of research conducted by Ng'ang'a & Valderhaug (1993) which attempted to assess prevalence and severity of dental fluorosis in the primary and permanent teeth of a sample of children living in Nairobi. The study was not experimental in that it did not manipulate any of the variables examined for the purpose of determining the effects of the variable on certain measures. Rather, it was an observational, cross-section study which examined data collected at one point in time.
In general, Ng'ang'a and Valderhaug's (1993) research examined for the presence of fluorosis as it existed in the sample at the time the study was conducted. It was retrospective in the sense that attempts were made to look at already occurring factors (gender of the children, the degree of fluoride in nearby waters, etc.) and to determine whether these factors, to at least some extent, accounted for variance in fluorosis in primary and permanent dentition.
No hypotheses were formulated in the study. However, the implications of the introductory explanation for the research were that Ng'ang'a and Valderhaug (1993) sought answers to the following questions:
1. What is the prevalence and severity of fluorosis in sample children's primary teeth and in their permanent teeth?
2. Does degree of fluorosis (in primary and permanent detention) differ as a function of sample children's gender?
3. Does degree of fluorosis (in primary and permanent detention) differ depending upon whether children are living in an area served with b
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