Long-term retrospective observational cohort study on the survival rate of stepped screw titanium implants followed up to 20 years.

PURPOSE: The aim of this long-term retrospective study was twofold: (1) to evaluate the survival and success rates of stepped screw titanium implants with a sandblasted and acid-etched surface, and (2) to assess the influence of hypothetical predictors of implant failure on the survival rate. MATERIALS AND METHODS: From 75 possible candidates, 67 patients contributing 346 Frialit-2 (DPS Frialit-2 implant system, Friatech) implants placed between 1997 and 2005 were retrospectively evaluated. The inclusion criteria consisted of implants placed in either native or augmented bone, rehabilitated with an implant-supported prosthesis, and radiographically documented at the time of prosthetic loading (T0). At the follow-up recall performed between January and October 2018 (T1), clinical and radiologic examinations were conducted to evaluate the survival and success rates. The influence of specific variables on the survival rate was subsequently investigated, including gender and smoking habits, location and size of the implants, and bone augmentation procedures. Cox regression and shared frailty models were used, with the patient representing the statistical unit. RESULTS: A survival rate of 91.62% over a median observation time of 189 months with a range of 11 to 20 years was observed. A total of 14 out of 29 implants failed before delivery of the provisional prosthesis. Overall, the median marginal bone loss was 1.25 mm, with an annual increase of 0.12 mm. Different from the other variables, the results of the multivariate model indicated that smoking was strongly correlated with implant failure (P = .002). CONCLUSION: Considering the limitations of this study, stepped screw titanium implants with a sandblasted and acid-etched surface provided a good survival rate. Smoking might be considered a relevant risk factor for implant failure.

Reproducibility of a Digital Method to Evaluate Soft Tissue Modifications: A study of Inter and Intra-Operative Measurement Concordance.

BACKGROUND: The soft tissue healing and quality around dental implant is a current debated topic in the recent literature. The free gingival margin and the quantity and quality of the mucosa around teeth and surrounding dental implants still determine the hard and soft tissue healing status. OBJECTIVE: The aim of this study is to assess inter and intra-operative measurement concordance of a method aimed at evaluating the apico-coronal migration of free gingival margin, using intra-oral photography. METHODS: The method was tested on peri-implant tissues that were treated with a connective tissue graft on the second stage surgery. Thirty-eight measurements on 13 implants in 8 patients were recorded. An intra-oral photograph was taken for the graft and the provisional crown, which enclosed a circular landmark with a previously determined diameter. The landmark was prepared with a red-resin by the same technician. Before crown cementation, the landmark was calibrated with a digital calibrator by the main investigator, to determine the precise diameter up to two decimal numbers. RESULTS: On the intra-oral photograph, the distance was measured from the most apical point of the determined landmark to the zenith of the gingiva, using an image-processing program designed for scientific multidimensional images (Image J). Three independent examiners took these measurements. CONCLUSION: The main advantage of the present non-invasive technique is that the spatial plane of the prosthetic landmarks is the same of the tooth unlike the utilization of periodontal probe, which is generally positioned on different plans in the space (generally more vestibular).

Soft-Tissue Enhancement Combined With Biologically Oriented Preparation Technique to Correct Volumetric Bone Defects: A Clinical Case Report.

The aim of the present case report was to illustrate how to obtain an ideal alveolar ridge contour by means of peri-implant soft-tissue management combined with the prosthetic approach of the biologically oriented preparation technique (BOPT). A patient presenting a moderate vertical and horizontal bone loss in the posterior maxilla was treated with sinus floor elevation and simultaneous implant placement. During the reentry procedure, the horizontal defect was corrected with an apically repositioned flap combined with a connective tissue graft. To increase the volume of the interimplant papillae, a pedunculated flap originating from the primary flap was turned within the interimplant space. BOPT one-time abutments have been employed to maximize the space available for the papilla-like tissues. A focused and combined surgical and prosthetic procedure has permitted enhancement of both peri-implant esthetics and function without the need for further invasive and costly bone regeneration techniques.