To measure is to know. If you cannot measure it, you cannot improve it : Lord Kelvin. The teeth and their surrounding structures are so definite, so easy to observe and carry them, so much of their previous disease history, that the measurement of dental diseases is much easier than this measurement of any other forms of the disease.Dental indices are tools used to quantify dental diseases thereby cross comparisons can be made based on disease burden and treatment efficacy. In dental literature, there exists an ambiguity on selecting the ideal scale or index to measure dental diseases. This is because of the availability of different indices and the lack of standardization among dental associations in measuring diseases. This warrants the need for a critical assessment of available indices commonly used in dental research and clinical practice. This book is to learn about dental indices used in children specifically.