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Updated: Aug 19, 2026

3D Planning and Printing of Patient Specific Implants for Reconstruction of Bony Defects
Published on: August 4, 2020
Pattern of permanent teeth present in individuals with ectodermal dysplasia and severe hypodontia suggests treatment
A D Guckes1, M W Roberts, G R McCarthy
1Department of Prosthodontics, University of North Carolina School of Dentistry, USA.
Purpose:
The objective of this study was to assess the pattern of permanent teeth present in a self-selected sample of 17 female and 35 male patients with ectodermal dysplasia presenting for treatment with dental implants.
Methods:
Mean age of sample: 18.7 years, age range: 5.9 to 60.9 years. Panoramic radiographs were examined independently by two investigators to determine the permanent teeth present. None of the sample reported extractions of permanent teeth prior to presenting for implants.
Results:
Permanent teeth most likely to be present, reported as a percentage of the patient sample with that tooth, were: maxillary central incisors (42%), maxillary first molars (41%), mandibular first molars (39%), maxillary canines (22%), mandibular second molars (17%), maxillary second premolars (15%), and mandibular premolars (12%). Comparing dentition by quadrants, mandibular anterior teeth (canines and incisors) were least likely to be present.
Conclusions:
Results support previous findings that the maxillary central incisors, maxillary first molars, mandibular first molars, and maxillary canines are the most conserved teeth in hypodontia. Successful use of osseointegrated implants in the anterior mandibles of most of these patients suggests that habilitation of the mandible with dental implant-supported prostheses is a reasonable option.
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