Evaluation of Bone Availability Skin Thickness Size of the Ear and relationship to the Cephalic Index for Selection and Placement of Implant in the Temporal Bone to Retain Auricular Prosthesis in Patients having Auricular Defects attending Tamilnadu Government Dental College and Hospital A Clinical study

Abstract

The bone availability in the temporal bone is proportionate to cephalic index. The bone availability in the temporal bone is shown in the decreasing order - Brachycephalic gt Mesocephalic gt Dolichocephalic. Skin thickness is not proportionate to cephalic index. The average skin thickness is 4-7mm in healthy individual. The average skin thickness is 7-12 mm in burn scar patients. A new instrument designed to measure the ear axis. Auricular index is formulated. The relationship between the Auricular index and cephalic index is = 1:1.5. AIM OF THE STUDY: To establish a guideline and treatment planning for implant retained auricular prosthesis by using cephalic index. OBJECTIVES: 1. To assess the bone thickness in the dried skull. 2. To assess the bone thickness at the proposed implant site using CT scan. 3. To assess the skin thickness at the implant site by needle penetration technique. 4. Morphometric evaluation of the ear - length, width, axis of the ear. MATERIALS AND METHODS: The materials and method for the study is divided in to four parts. Part I - Anatomical assessment of the bone availability in dry skull and its relation to cephalic index. Part II - Clinical assessment of the cephalic index, and measurement of bone thickness using CT scan and its relation to cephalic index. Part III - Clinical assessment of skin thickness by needle penetration method. Part IV - Evaluation of the morphology of the ear by morphometric and its relation to the cephalic index. CONCLUSION: Cephalic index influences the bone thickness in the skull for placing the implant to retain the auricular prosthesis. The bone availability in the skull is given in the decreasing order Brachycephalic gt Mesocephalic gt Dolichocephalic. Cephalic index does not have influence on the skin thickness and the morphometric measurement of ear. The new classification CITB (Cephalic index- temporal bone) on the bone availability in the temporal bone will help the clinician to select the length of the implant by relating to the shape of the head.