RESUMEN
The incorporation of computer-aided design/computer-aided manufacturing (CAD/CAM) technology into complete denture fabrication brings about several advantages to the fabrication process, providing better predictability of the desired outcomes and high accuracy of denture fit, mainly because the milling of prepolymerized acrylic resin eliminates the shrinkage of the acrylic base. Also, there is a decrease in the porosity when compared to a conventionally processed denture, and consequently there is a decrease in the retention of Candida albicans on the denture base. The presented workflow for complete denture fabrication presents a totally wax-free manufacturing process, combining rapid prototyping (RP) and rapid milling. With the presented technique, the maxillomandibular relation (MMR) and the ideal setup of the tooth arrangement are developed by using occlusion rims and trial setup made with RP. For the definitive final denture, the denture base and the basal surfaces of the conventional denture teeth were milled according to the individual clinical situation. Posteriorly, the teeth were adapted and bonded into the milled sockets of the milled base.
RESUMEN
OBJECTIVE: To evaluate dimensional alterations of the alveolar ridge that occurred following tooth extraction at sites grafted with Bio-Oss(®) Collagen. MATERIAL AND METHODS: Twenty-eight subjects with maxillary incisors, canines, and premolars scheduled for extraction were included. The tooth was carefully removed. The patients were randomly assigned to a test or a control group. In the test group patients, Bio-Oss(®) Collagen was placed in the fresh extraction socket while in the controls no grafting was performed. Radiographic examination (cone beam computed tomograms, CBCT) was performed immediately after tooth extraction and socket treatment. Four months later, a new CBCT was obtained. In the radiographs, (i) the distance (mm) between base of the alveolar process (apex) and the buccal and palatal crests was determined, (ii) the outer profile of alveolar process of the experimental sites was outlined, and the cross section of the area (mm(2) ) determined. RESULTS: After 4 months of healing, the buccal and to a less extent also the palatal bone plate had become markedly reduced in height. The placement of a biomaterial in the socket failed to prevent resorption of the buccal and palatal bone walls. The cross-sectional area of the control ridge was reduced about 25% and of the test ridge with 3%. CONCLUSION: The placement of a xenograft in fresh extraction sockets markedly counteracted the reduction in the hard tissue component of the edentulous sites.