The accuracy of alveolar crest dimensions measurement for dental implants. In vitro study

The aim of this study was to evaluate the accuracy of radiological examination methods in quantitative preimplantar bone assessment.

The study was carried out on a dry cranium, totally edentate. There have been radiological appreciated the height of the alveolar process and its width, both to the maxilla and the mandible. Also, it has been established the distance between the free edge of the alveolar crest and the superior edge of the mandibular canal. The values radiological measured have then been compared with those obtained through direct measurement of these dimensions on the cranium.

The results were performed in tables and diagrams. The greatest deviation from the real values was at the panoramic radiography, while the computer tomography was the most accurate examination among the radiological techniques used in this study. The panoramic radiography doesn't give information about the alveolar crest thickness, about it's declivity and the alveolar crest measurement generates significant errors. Linear tomography implies a difficult technique, but it has the advantage of a low irradiation,a wider accessibility and a lower cost than the CT. Computer tomography is the most accurate preimplantar evaluation technique but it has the disadvantage of a high patient radiation.

The panoramic radiography represents an insufficient method for appreciating the preimplantar bone status. That's why it has to be supplemented with other radiological examinations, especially at the cases with alveolar crest atrophy, to avoid accidental penetration of adjacent structures.