A digital workflow for computer-guided implant surgery integrating CBCT, model scanning, and CAD/CAM for a complete edentulism implant-supported prosthesis: a technique procedure.

The utilization of digital 3D surface images (STL format) for planning cases of computer-guided implant surgery is very useful in partially edentulous cases. In fully edentulous cases, however, the absence of teeth makes it necessary to add reference markers. The proposed protocol demonstrates a simple procedure that allows for the superimposition of STL and radiologic data (DICOM format). In the presented patient case, the tissue-bearing area of the prosthesis was relined with a polysulfide impression material and sent to the laboratory. A master cast was produced. The prosthesis was relined to improve intraoral stability and was provided with at least three radiopaque 3D markers. An STL copy of the prosthesis and the model was generated through a laboratory scanner. The patient wore the prosthesis with the attached markers during the 3D radiologic examination. In the planning software (CoDiagnostiX; Dental Wings), the prosthesis markers on the STL were matched to the corresponding markers visible on the DICOM data. Then, the STL of the model was matched to that of the prosthesis. Once the STL of the mucosa and the prosthesis were imported into the software, new possibilities arose, ie, the option to add other digital or traditional tooth setups to the same radiologic data or to design a surgical guide based on the actual mucosa of the patient.

Special-needs patients in pediatric dentistry: Progeroid syndrome. A case of dental management and oral rehabilitation.

This report presents a case of an eightyear- old girl affected by a progeroid syndrome of unclear genetic origins. The patient's dental history included oligodontia, premature deciduous exfoliation and roots abnormalities. She was treated with comprehensive oral rehabilitation using dentures. Oral health instructions were given during the whole treatment and follow- up period. The goal of improving the masticatory function and the esthetic was achieved, allowing the patient to increase her social abilities and self-confidence.

Implant supported cantilevered fixed dental rehabilitations in partially edentulous patients: Systematic review of the literature. Part I.

OBJECTIVES: To investigate in which clinical situations a cantilever fixed implant supported restorations can be a treatment alternative and which complications are reported. MATERIALS AND METHODS: Two operators screened the literature (MEDLINE, EMBASE) and performed a hand search on the main journals dealing with implantology and prosthetics until 31 December 2017. Only articles that considered cantilever implant fixed restorations with at least 10 patients and with a mean follow-up of at least 5 year were selected. The outcome variables were survival of implants and prosthesis, mechanical, technical and biological complications, marginal bone loss. The review was performed according to the PRISMA statements. Risk of bias assessment was evaluated. Failure and complication rates were analysed using random effect Poisson regression models to obtain summary estimate of 5- and 10-year survival and complication rates. RESULTS: A total of nine papers were selected for partially edentulous patients and reported high survival rate of the prosthesis. The estimated survival rate for 5-10 years was calculated to be 98.4% for the implants and 99.2% for the rehabilitations. Mechanical, technical and biological complications were reported with a cumulative 5-10 years complication rate of 28.66% and 26.57% for the patients and for the prosthesis, respectively. Two papers for single implant supporting 2-unit cantilever were not sufficient to draw conclusions. CONCLUSIONS: There is evidence that cantilever can be successful treatment in partially edentulous patients. In two adjacent edentulous sites, data are not yet sufficient.

Implant-supported cantilevered fixed dental rehabilitations in fully edentulous patients: Systematic review of the literature. Part II.

AIM: To investigate fully edentulous patients rehabilitated with cantilever-fixed implant-supported restorations and to analyse which complications are reported for this type of treatment. MATERIALS AND METHODS: Two operators screened the literature (MEDLINE, EMBASE) and performed a hand search on the main journals dealing with implantology and prosthetics until 31 December 2017. Only articles that considered cantilever implant-fixed restorations with at least 10 patients and with a mean follow-up of at least 5 years were selected. The outcome variables were survival of implants and prosthesis, mechanical, technical and biological complications, marginal bone loss. The review was performed according to the PRISMA statements. The risk of bias was evaluated for each article. Failure and complication rates were analysed using random effect Poisson regression models to obtain summary estimate of 5- and 10-year survival and complication rates. RESULTS: Fourteen papers for fully edentulous patients were selected. The estimated 5 to 10 years survival rate was calculated to be 99.00% and 96.7% for the implants and the prosthesis, respectively. A total of 299 complications (technical and biological) were reported with a cumulative 5-10 years complication rate of 44.41% and 39.46% for the patients and for the prosthesis, respectively. CONCLUSIONS: There is evidence that cantilever can be successful treatment in fully edentulous patients.

6 mm vs 10 mm-long implants in the rehabilitation of posterior jaws: A 10-year follow-up of a randomised controlled trial.

PURPOSE: The aim of this study was to compare survival and success rates of 6 mm-long and 10 mm-long implants in partially edentulous posterior areas. MATERIALS AND METHODS: Twenty-four patients with a partially edentulous area were included in the study. Patients were randomly allocated according to a parallel group design to receive 6 mm or 10 mm-long implants. A total of 54 implants were placed (26 × 6 mm implants). Patients were followed for 10 years after prosthetic loading. Outcome measures were prosthesis and implant survival, marginal bone level changes and complications. RESULTS: After 10 years, 17 patients (eight with 6 mm implants and nine with 10 mm implants) were available: three 6 mm and four 10 mm patients were lost to follow-up. One 6 mm implant failed during the healing period and its related prosthesis could not be placed. No implants were lost after loading. Nine patients in the 6 mm group registered a total of 15 complications: two mucositis, six decementations and seven chippings. Ten patients in the 10 mm group registered a total of 13 complications: five mucositis, two decementations and six chippings. Overall the difference for complications between the two groups was not statistically significant (P = 0.22; difference in proportion = -0.02; 95% CI: -0.31 to 0.27). Decementations in the 6 mm group were statistically significant higher than the 10 mm group (P = 0.04; difference in proportion = 0.39; 95% CI: 0.03 to 0.74). Marginal bone loss at 10 years was 0.84 and 0.37 mm with the 6 mm and 10 mm groups, respectively (difference between the two groups 0.49 mm; 95% CI -0.31; 1.29; not statistically significant: t test P = 0.22). CONCLUSIONS: Rehabilitations supported by 6 mm or 10 mm-long implants showed similar clinical outcomes in terms of survival and success rates, although 6 mm implants had more decementations.

Comparison of Cemented vs Screw-Retained, Customized Computer-Aided Design/Computer-Assisted Manufacture Zirconia Abutments for Esthetically Located Single-Tooth Implants: A 10-Year Randomized Prospective Study.

PURPOSE: To compare the clinical outcomes of screw-retained vs cemented single crowns supported by customized zirconia abutments on implants. MATERIALS AND METHODS: Thirty-two patients received implant-supported (Regular Neck, Tissue-Level, Straumann AG), single-tooth restorations with customized zirconia abutments in the anterior areas. Participants were randomly assigned to the screw-retained (full-crown abutment [FCA]) group or the cemented (zirconia crown [ZrC]) group and followed up over a 10-year period. Prosthetic and biologic complications, marginal bone level (MBL), mucosal recession, and pink and white esthetic scores (PES and WES, respectively) were evaluated. RESULTS AND CONCLUSION: There were no implant failures during the study period; after 10 years, 94% of crowns were functional. Prosthetic complications were recorded in both groups (three FCA and two ZrC), and no significant difference was found (P = .65). Two cases of mucositis were recorded, one in each group. Esthetic outcomes were assessed using PES and WES scores. MBL was 0.95 mm in the ZrC group and 0.82 mm in the FCA group, with no significant difference between groups. These encouraging preliminary results need to be confirmed with long-term follow-up on larger study samples.

Stratification of prosthetic complications by manufacturer in implant-supported restorations with a 5 years' follow-up: systematic review of the literature.

INTRODUCTION: Prosthetic complications on implant-supported restorations have been documented in several papers published in the literature. Several manufacturers are present on the market but results are often cumulated and may thus be misleading. The objective of the present review is to assess the prosthetic complications of implant-supported restorations with particular interest of the results obtained with prostheses from different manufacturers. EVIDENCE ACQUISITION: A manual search of Medline/PubMed was carried out up to June 2016, yielding a total of 6832 articles, which were narrowed down to 1450, then 347 abstracts to include 55 papers after full text reading. Papers with at least 5 years of follow-up reporting on prosthetic complications of single and fixed partial prosthesis were included. Prosthetic complications were divided into mechanical and technical complications, and reported in a table. EVIDENCE SYNTHESIS: Overall 14.4% of prosthetic complication was found for a total of 6623 restorations followed for an average of 7.4 years (range 5-16 years). Results where then sorted and compared. Single crowns were affected by 1.4% of mechanical complications and 10.9% of technical complications after a mean of 7.4 years. Fixed partial prosthesis were affected by 2.5% of mechanical complications and 18% of technical complications. Screw-retained and cemented restorations were calculated to have a 5 years rate of complications of 21.2% and 9.3%, respectively, which demonstrated a statistically difference with fisher exact test with P<0.1. Only 3 manufacturers presented more than 10 articles and were directly compared with Fisher's exact test with P<0.1. The incidence of overall complications was estimated to be after 5 years of 11.2%, 10.8% and 13.8% for Straumann, Nobel, and Astratech, respectively, but dividing results in mechanical and technical complications, gave different results. Straumann was estimated to have less mechanical complications after 5 years in respect to Nobel and Astratech, but the three were similar for technical complications. CONCLUSIONS: although studies present very different material and methods and do not report all data, some conclusions can be made. The difference between mechanical complications lead the authors to suppose that there might be a difference in results obtained by different implant abutment connections. It is also noticed that all papers were published by expert clinicians and universities research centers that apply rigid surgical and prosthetic protocols and use original abutments.

Reproducibility of Buccal Gingival Profile Using a Custom Pick-Up Impression Technique: A 2-Year Prospective Multicenter Study.

PURPOSE: The aim of this study was to transfer the provisional restoration emergence profile to the final implant-supported restoration and to buccal gingival margin (BGM) stability after 2 years of function. MATERIALS AND METHODS: A total of 33 patients were recruited for treatment of single gaps by means of 33 implant-supported restorations. Fixed provisional crowns were screwed to the fixture and adjusted until the complete peri-implant soft tissue maturation was achieved. After 12 weeks, a second fixture impression was taken by means of a pick-up customization technique in order to transfer the clinical aspect of the peri-implant soft tissues to the master cast. A definitive restoration was delivered. A standardized method from digital photographs was used to assess the gingival margin modification (BGM) from the provisional (P) to the definitive prosthesis installation at baseline (D0), and after 1 (D1) and 2 years (D2) of function. Also, marginal bone loss (MBL) was calculated after 1 (D1) and 2 years (D2) of definitive restoration function. RESULTS: The BGM index at the time of the final restoration installation (D0) was 0.12 ± 0.33 mm if compared with the BGM position of the provisional restoration (P); it was of 0.12 ± 0.46 mm after 1-year of follow-up (D1) and of 0.31 ± 0.21 after 2 years of function (D2). No significant difference was calculated between measurements in different follow-up visits (p > 0.05). No significant MBL was measured between the baseline (D0) and the 1-year follow-up (p = 0.816) with a mean MBL value of 0.2 ± 0.1 mm. Similar result was calculated after 2 years (p = 0.684) with a mean MBL value of 0.3 ± 0.2. CONCLUSION: A modified impression pick-up may be helpful to reproduce the gingival margin position from the provisional to the definitive restoration. Moreover, the gingival zenith position during the follow-up period seemed to be stable. CLINICAL SIGNIFICANCE: The modification of the standard impression pick-up technique may contribute to reproducing a natural emergence profile of esthetic implant prosthetic restorations (from the provisional to the definitive restoration.) With this technique, implant soft tissues stability around CAD-CAM (computer aided design-computer aided manufacturing) abutments can be easily obtained, and the customized abutment shape may better support the scalloped peri-implant soft tissues architecture, especially in anterior areas.

Six-mm versus 10-mm long implants in the rehabilitation of posterior edentulous jaws: a 5-year follow-up of a randomised controlled trial.

PURPOSE: To compare the clinical outcome of 6-mm and 10-mm long implants in partially edentulous posterior areas. MATERIALS AND METHODS: Twenty-four patients, with a partially edentulous area in the jaws with a height and width allowing the positioning of 2 to 3 adjacent 10 × 4.1 mm implants without any augmentation procedure, were randomly allocated according to a parallel group design to receive 6-mm long or 10-mm long implants. A total of 54 implants were placed (26 × 6 mm and 28 × 10 mm implants). Patients were restored 8 weeks after surgery and were followed for 5 years. Outcome measures were prosthesis and implant survival, as well as marginal bone level changes and complications. RESULTS: After 5 years, 18 patients were available. One 6 mm implant failed during the healing period and its related prosthesis could not be placed. No implants were lost after loading. The 6 mm group registered 5 complications (1 mucositis, 3 prosthesis decementations and 1 chipping), while only 3 were registered in the 10 mm group (2 decementations and 1 chipping). The difference in complications between the two groups was not statistically significant (P = 0.39). Marginal bone loss at 5 years was 0.43 and 0.24 mm with the 6 mm and 10 mm groups, respectively (not statistically significant; difference between the two groups 0.19 mm; SD 0.23 mm; 95% CI -0.34;0.73; t test P = 0.42). CONCLUSIONS: Implant and prosthetic survival and success rates were similar between prostheses supported by 6-mm or 10-mm long implants.

Phagocyte spreading and phagocytosis in the compound ascidian Botryllus schlosseri: evidence for an integrin-like, RGD-dependent recognition mechanism.

The involvement of integrins in phagocyte spreading and phagocytosis was investigated in the compound ascidian Botryllus schlosseri. The number of spreading cells was significantly reduced when adhesion occurred in the presence of the tetrapeptide Arg--Gly--Asp--Ser (RGDS), but not of Arg--Gly--Glu--Ser (RGES) indicating the involvement of RGD-mediated adhesion mechanisms in phagocyte spreading. The significant decrease of the fraction of spreading cells in the presence of Botryllus blood plasma suggests the presence of RGD-containing molecules in the blood of our species. The increase in the same index when blood plasma-coated slides as well as fibrinogen- and fibronectin-coated coverslips were used, fits with the above hypothesis. Adhesion in the presence of RGDS leads to a consistent alteration of the actin cytoskeleton, in agreement with the known role of integrin adhesion in microfilament organization. Phagocytosis was greatly reduced by RGDS in the incubation medium, but not by RGES, and was significantly increased by coating yeast cells with fibronectin or blood plasma. Both spreading and phagocytic capability were severely inhibited by wortmannin, suggesting the importance of phosphatidylinositol-3-kinase in integrin-mediated signal transduction in ascidians.