Abstract: Algorithm for the treatment of unilateral condylar hyperplasia（UCH） is based on the assessments of the growing of the condyle. Isotope bone scan is as a new assessment way which contains two mainly ways of planar imagine scintigraphy and single photon emission computed tomography, and no dubiety superior to the clinical and traditional radiological way in the diagnosis and planning of treatment of UCH. Thus, many scientists and clinical surgeons have been doing many research on isotope bone scan technique of its mechanism, different assessment ways, and their applying to the assessments of the growing of the condyle in the diagnosis and planning of treatment of UCH, how they work up and also their advantage and disadvantage compared to the clinical way and each other. This article is introducing the new findings and results in recent years.