ou zon . ▁ ▁Tre at ment ▁The ▁c ran io fa cial ▁surg ery ▁to ▁correct ▁hy pert elor ism ▁is ▁usually ▁done ▁between ▁five ▁and ▁eight ▁years ▁of ▁age . ▁This ▁addresses ▁the ▁psych oso cial ▁aspects ▁in ▁the ▁child ' s ▁early ▁school ▁years . ▁Another ▁reason ▁for ▁correction ▁age ▁five ▁or ▁older ▁is ▁that ▁the ▁surg ery ▁should ▁be ▁delayed ▁until ▁the ▁to oth ▁bud s ▁have ▁grown ▁out ▁low ▁enough ▁into ▁the ▁max illa , ▁thus ▁prevent ing ▁damage ▁to ▁them . ▁Also , ▁before ▁age ▁five ▁the ▁c ran io fa cial ▁b ones ▁are ▁thin ▁and ▁frag ile , ▁which ▁can ▁make ▁surg ical ▁correction ▁difficult . ▁In ▁addition , ▁it ▁is ▁possible ▁that ▁orb ital ▁surg ery ▁during ▁inf ancy ▁may ▁in hib it ▁mid face ▁growth . ▁ ▁For ▁the ▁treatment ▁of ▁hy pert elor ism ▁there ▁are ▁two ▁main ▁oper ative ▁options : ▁The ▁box ▁o ste ot omy ▁and ▁the ▁fa cial ▁b ipart ition ▁( also ▁referred ▁to ▁as ▁median ▁fas ci ot omy ). ▁ ▁Box ▁o ste ot omy ▁This ▁treatment ▁of ▁orb ital ▁hy pert elor ism ▁was ▁first ▁performed ▁by ▁Paul ▁T ess ier . ▁The ▁surg ery ▁starts ▁off ▁by ▁various ▁o ste ot om ies ▁that ▁separate ▁the ▁entire ▁b ony ▁part ▁of ▁the ▁orbit ▁from ▁the ▁sk ull ▁and ▁surrounding ▁fa cial ▁b ones . ▁One ▁of ▁the ▁o ste ot om ies ▁consists ▁of ▁removing ▁the ▁b one ▁between ▁the ▁or bits .