Angulated screw channels (ASC) allow the clinician to reposition the access hole of screw-retained restorations, improving the design of the rehabilitation and the esthetic outcome. Few clinical studies are available on the efficacy of these restorations, especially at longer follow-ups and with a large number of subjects. The objective of this study was therefore to retrospectively evaluate patients rehabilitated with screw-retained restorations using ASC. The time of delivery and their adherence to the maintenance program was obtained, as well as the characteristics of the restoration and of the patient’s occlusion; a Kaplan–Meier survival curve was then built to investigate the success rate of these restorations and the effects of several variables were evaluated with a Cox model. A total of 105 subjects and 162 implants were enrolled in this study; after 42 months a success rate (92%) similar to what is reported for conventional screw-retained restorations was encountered. Monolithic zirconia restorations (n = 52) had a higher success rate (95%) when compared to partially veneered restorations (n = 53), which suffered a higher number of complications (90%). The other variables had no statistically significant effect. Implant supported prostheses adopting ASC provide a favorable outcome both in the posterior and anterior regions and can therefore be adopted to treat cases where the implant angulation is unfavorable for a conventional screw-retained prosthesis.

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Edentulous patients’ quality of life can be greatly diminished by the use of a badly fitting removable prosthesis, as many aspects of social life become notably impaired. The object of this study was to evaluate if treating these patients with a two implants mandibular overdenture could improve their quality of life as measured with the Italian version of the OHIP-14 (Oral Health Impact Profile). Edentulous patients, in good clinical condition, were selected. Two implants were placed following the recommended guidelines and three months after new mandibular dentures were manufactured, implants were uncovered and connected to the prosthesis using LOCATOR abutments. OHIP-14 was measured at baseline, one month after delivery and one year after delivery. An improvement was observed even after one month (with a mean reduction of 17 points in OHIP) and that improvement appeared to be stable at the one-year follow-up. Mandibular overdentures can improve a patient’s quality of life when compared to a tissue-supported removable complete denture, as long as the patient is subjected to an appropriate follow-up as the retentive rings of the attachment can deteriorate even after two years and lose a great deal of retentive capabilities.