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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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According to Hoyme et al classification of hemihyperplasia, Hemifacial hyperplasia involves:
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The correct answer is  Hoyme et al (1998) provided an anatomic classification of hemihyperplasia: 

Complex hemihyperplasia is the involvement of half of the body (at least one arm and one leg); affected parts may be contralateral or ipsilateral.
Simple hemihyperplasia is the involvement of a single limb.
Hemifacial hyperplasia is the involvement of one side of the face.

Ref: Shafer's textbook of oral pathology 7th edition page 14