Marked differences existed with respect to tissue composition of the edentulous ridge between the maxilla and the mandible. The cortical crest was wider in the mandible than in the maxilla, and widest in the symphysis region of the mandible. The proportion of bone marrow was greater in the maxilla than in the mandible. The maxillary front tooth region was poor in lamellar bone but rich in bone marrow, while the anterior mandible contained large amounts of mineralized bone but small amounts of bone marrow.

A graft comprised of collagen-enriched deproteinized bovine bone mineral, placed to fill extraction sockets failed to influence the overall diminution of the ridge that occurred during healing. The thickness of the buccal bone wall apparently had a significant influence on volumetric alterations of the edentulous ridge following tooth extraction.

Summary Objectives This observational clinical study evaluated the patient satisfaction and the clinical outcomes of edentulous arches rehabilitated with overdentures retained by CAD‐CAM milled titanium bars. Materials and Methods Edentulous patients were treated with a full‐arch removable overdenture anchored on two milled bars based on a friction retention system. Patient satisfaction was tested using the validated Oral Health Impact Profile (OHIP‐14) questionnaire at the pre‐ and post‐treatment visits, up to two years after prosthesis delivery (possible score range: 0‐56. Best: 0). The prosthodontist satisfaction was also assessed through a designed questionnaire (best possible range 0‐4. Best:0). Radiographic and clinical examinations were performed at baseline and after 2 years of function. Implant and prostheses complications were recorded. Results Forty (25 mandible) edentulous patients, mean age 69 ± 9.5 (SD) (52% males, 10% smokers), were treated with a total of 185 implants. The mean difference between pre‐ and post‐treatment OHIP‐14 score was 20.6 ± 8.0 (P < 0.0001) showing a high level of satisfaction for aesthetics, functional and psychological outcomes. This perception was not influenced by patient's age or gender. The clinicians' mean score was 3.4 ± 4.0. There was a marginal bone level (MBL) gain of 0.02 ± 0.22 mm between the two time points. Minor complications were reported in five patients. Conclusions This procedure may lead to satisfaction regarding aesthetics and mastication function. One of the most relevant aspects is the versatility, which allows selection of the most suitable treatment option according to patient needs. The prosthodontist satisfaction questionnaire showed that this procedure met the clinical expectations.

This assignment applies to all translations of the Work as well as to preliminary display/posting of the abstract of the accepted article in electronic form before publication. If any changes in authorship (order, deletions, or additions) occur after the manuscript is submitted, agreement by all authors for such changes must be on file with the Publisher. An author's name may be removed only at his/her written request. (Note: Material prepared by employees of the US government in the course of their official duties cannot be copyrighted.

ObjectivesThis RCT compares marginal bone level (MBL) change and the clinical parameters after a 3‐year function in maxillary implant‐supported fixed complete dentures (FCDs) treated with four‐implants (4‐I) or six‐implants (6‐I).Material and methodThree centres treated 56 patients with 280 implants allocated to the 4‐I or 6‐I group. Radiographic and clinical examinations were performed. The primary outcome was to investigate MBL change between the groups.ResultsImplant survival rates were 100% and 99% in the 4‐I and 6‐I groups, respectively. Considering the clustering effects, the MBL change was not significantly different between the groups over the 3‐year follow‐up. The MBL in the 4‐I group was 0.30 ± 0.50 mm at baseline, 0.24 ± 0.31 mm at 1 year and 0.24 ± 0.38 mm at 3 years. In the 6‐I group, MBL was 0.14 ± 0.32 mm at baseline, 0.16 ± 0.35 mm at 1 year and 0.12 ± 0.26 mm at 3 years. There was a statistically significant difference between the groups at BL and 3Y. No significant differences between the groups were reported for clinical parameters at each time point as well as in between the visits. The technical and biological complications rates were 1.6% and 6.0%, respectively. Prosthetic complications affected 25 FCDs (47.2%).ConclusionMarginal bone level change revealed a stable condition in the 3‐year period in the two groups. Few technical and biological complications occurred apart from the chipping/fracture of the prosthetic teeth. Four‐implant is a feasible solution if the rehabilitation is oriented towards the most cost‐effective treatment and towards avoiding bone augmentation procedures. Clinicians have to consider the potential required visits for prosthetic maintenance.