Prosthetic Survival Rate Research Articles

Effect of Simultaneous Immediate Implant Placement and Guided Bone Reconstruction with Ultra-Fine Titanium Mesh Membranes on Radiographic and Clinical Parameters after 18 Months of Loading.

Background: The aim of the present prospective case series study was to evaluate the implant and prosthetic survival rates, complications and marginal bone loss using ultra-fine titanium mesh membrane with simultaneous implant placement, to provide space maintenance mandatory for guided bone reconstruction of alveolar bone defects. Materials and Methods: patients were recruited and treated at a private clinic in Rome, Italy, between March 2016 and October 2017. Self-tapping tapered implants were placed through a computer-guided template-assisted approach. Autogenous bone was placed alone over the exposed implant surface, then mixed with inorganic bovine bone material. Finally, the membrane was connected and shaped in order to securely enclose the graft area, and the healing cap was connected and screwed onto the height connector. Outcome measures were: implant and prosthetic failure, biological and mechanical complications, marginal and volumetric bone level changes, esthetic evaluation performed according to the pink aesthetic score (PES). Results: in total, seven patients (five women, two men) with a mean age of 52.7 ± 20.3 years (range: 27–71) received 10 self-tapping tapered implants and simultaneous guided bone regeneration with ultra-fine titanium mesh membranes. No implants and no prostheses failed during the entire follow-up period. One slightly membrane exposure was observed one month after implant placement in one patient. The mean marginal bone loss (MBL) at implant loading was 0.13 ± 0.09 mm (95% CI 0.08–0.19). At the 18-month follow-up examination, the mean MBL was 0.28 ± 0.33 mm (95% CI 0.07–0.50) The difference was not statistically significant (0.15 ± 0.31; 95% CI 0.05–0.35; P = 0.1888). The mean horizontal alveolar ridge width was 3.72 ± 1.08 mm (95% CI 3.22–4.22 mm). At the II-stage surgery, the mean bone width was 8.79 ± 0.98 mm (95% CI 8.51–9.07 mm). The mean bone gain was 5.06 ± 1.13 mm (95% CI 4.68–5.44 mm; P = 0.000). The mean volume of the grafted bone calculated using the superimposition technique was 0.99 ± 0.38 CC (95% CI 0.75–1.23 CC). The mean PES at implant loading was 8.2 ± 0.8 mm (95% CI 7.7–8.7). At the 18-month follow-up examination, the mean PES was 12.0 ± 0.7 mm (95% CI 11.5–12.5) The difference was statistically significant (3.8 ± 0.4; 95% CI 3.5–4.1; P = 0.0000); Conclusion: with the limitation of the present prospective study, the guided bone reconstruction using an ultra-fine titanium mesh membrane with simultaneous implant placement seems to provide good and stable results in implant/prosthesis success. Further research with a longer follow-up and a higher sample size are needed to confirm the results from this preliminary report.

The All-on-4 treatment concept for the rehabilitation of the completely edentulous mandible: A longitudinal study with 10 to 18 years of follow-up.

There is a need for studies evaluating the long term outcomes of the All-on-4 treatment concept. To evaluate the long term clinical and radiographic outcomes of the All-on-4 treatment concept in the mandible. This retrospective longitudinal case series study included 471 patients (women: 286, men: 185, average age = 57.7 years) rehabilitated with 1884 implants in immediate function supporting 471 fixed full-arch mandibular prostheses and followed for 10 to 18 years. Primary outcome measures were prosthetic survival and implant success and survival (estimated using life tables). Secondary outcome measures were marginal bone loss (MBL) at 10 and 15 years, biological and mechanical complications. Multivariable analysis was used to estimate potential risk indicators for implant failure (Cox regression to estimate hazard ratios and 95% confidence intervals (95%CI)), MBL > 3 mm at 10 and 15 years, biological and mechanical complications (binary logistic regression to estimate odds ratios [ORs] with 95%CI). Twenty-seven patients deceased (5.7%) and 149 patients (31.6%) were lost to follow-up. The cumulative prosthetic survival rate was 98.8%; the implant cumulative survival and success rate was 93% and 91.7%, respectively up to 18 years of follow-up. Previous biological complications (HR = 4.43) were significantly associated with implant failure. Average (95% CI) MBL at 10- and 15-years were 1.72 mm (95%CI: 1.59, 1.85) and 2.32 mm (95% CI: 1.98, 2.66). Smoking (OR = 2.72), previous failure of a contiguous implant (OR = 3.89) and biological complication (OR = 8.11) were associated with MBL > 3 mm. The incidence of biological complications was 11.8% at implant level, with previous failure of a contiguous implant (OR = 5.56), smoking (OR = 1.75), and systemic condition (OR = 1.65) were significantly associated. The incidence of mechanical complications was 36.7% with male gender (OR = 1.67) and type of prosthetic material used in the restoration significantly associated (metal-acrylic OR = 0.30; metal-ceramic OR = 0.22)). Considering the implant, prosthetic and MBL outcomes it is concluded that the All-on-4 is a viable treatment option validated in the long term. Nevertheless, biological and mechanical complications can occur.

Conventional versus Digital Impressions for Full Arch Screw-Retained Maxillary Rehabilitations: A Randomized Clinical Trial.

Background: The objective of this study was to compare conventional versus digital impressions for Full-Arch maxillary rehabilitations. Methods: Patients selected for this study were treated with full-arch screw-retained rehabilitations supported by six immediately loaded dental implants. Patients have been scheduled randomly into control (conventional impression group, CIG) and test (digital impression group, DIG) groups respectively for a fully conventional workflow and a fully digital workflow. In both groups, within 24 h, temporary prostheses were delivered. Four months after the implant positioning, the two groups dealt with the fabrication of definitive restorations: conventional pick-up was performed in the control group, and definitive digital impressions were carried out in the test group. The time involved following these two procedures was recorded. Patients underwent intraoral digital radiographs to evaluate the accuracy of the framework-implant connection, check for the presence of voids at the bar-implant connection and measure bone level. Criteria used to assess success at the prosthetic level were the occurrence of prosthetic maintenance, the absence of fractures of the acrylic resin superstructure and voids. Results: A total of 50 patients received immediately loaded prostheses supported by six implants (total 300 implants). A fixture and prosthetic survival rate of 100% was observed. All digital X-ray examinations revealed a bar-implant connection accuracy and no voids. Differences that were not statistically significant (p > 0.05) in marginal bone loss were found between control and test groups. Significantly less time was spent to perform digital impression procedure (p < 0.05). Conclusions: Clinical and radiological results of the test group advocate a satisfactory accuracy and predictability of the intraoral scanner (IOS) to be a reliable alternative in clinical practice for implant full-arch rehabilitations and suggest fabrication of definitive restorations with a successful marginal fit precision.

Megaprosthetic replacement of the distal humerus: still a challenge in limb salvage

The distal humerus is a rare location of bone tumors. Because of the complexity of the elbow joint, poor soft-tissue coverage, and proximity of nerves and vessels, resection and endoprosthetic reconstruction are demanding. This retrospective study evaluated the clinical results after distal humeral resection and megaprosthetic reconstruction in 12 patients with an average age of 46 years. All patient files were reviewed for clinical information, and postoperative function and patients' contentment were assessed using the Musculoskeletal Tumor Society score. The predominant diagnoses were bone and soft-tissue sarcoma (n = 6), giant cell tumor (n = 2), and renal cell carcinoma metastasis (n = 2). Local recurrence was the reason for secondary amputation in all cases (n = 3). The prosthetic survival rate after surgery was 82% at 2 years and 64% at 5 years. Reconstruction failure was mainly caused by aseptic loosening of the humeral stem, occurring in 27% (n = 3), followed by aseptic loosening of the ulnar stem in 9% (n = 1) and periprosthetic infection in 9% (n = 1). The mean Musculoskeletal Tumor Society score was 24 points (range, 20-30 points). An extension lag of more than 10° was noted in 6 patients (55%). Our results suggest that limb salvage with a distal humeral replacement can achieve good functional results in most patients, although the complication rate with special emphasis on the loosening rate of the humeral stem is high. However, limb salvage was not achieved in 27% of patients because of local recurrence.

Do the New Hydrophilic Surface Have Any Influence on Early Success Rate and Implant Stability during Osseointegration Period? Four-Month Preliminary Results from a Split-Mouth, Randomized Controlled Trial.

Objective The objective of this study is to compare the implant stability of Hiossen ET III implants with its new hydrophilic (NH) surface and Hiossen ET III implants with the sandblasted and acid-etched (SA) surface. Materials and Methods Patients required at least two teeth to be rehabilitated with a fixed, implant-supported restoration, consecutively enrolled. Patients randomly received SA surface implants (SA group) or SA implants with a newly developed bioabsorbable apatite nanocoating (NH group). Outcome measures were implant and prosthetic survival rate, complications, insertion torque, and implant stability quotient (ISQ) measured at implant placement and every week up to 8 weeks after implant placement. Comparison between groups was made by unpaired t -test, while the comparison between each follow-up will be made by paired t -tests to detect any change during the follow-up. Complications and failures were compared using Fisher's exact test. Results A total of 14 patients were treated with 28 implants (14 SA and 14 NH). No implant and prosthesis failed 4 months after implant placement. No complications were experienced. At the 2nd week after implants placement, two implants in the SA group showed discontinuous measurements versus none in the NH group ( p = 0.4815). Implants unscrewed during ISQ measurements and were rescrewed. Data recording stopped for 6 weeks. Both implants osseointegrated without any further complication. The NH implants did not show physiological ISQ decrease between 2nd and 4th week after implant placement, showing a more even pattern of ISQ values compared with SA implants (77.1 ± 4.6 vs. 72.9 ± 11.5; difference: 4.2 ± 12.1; p = 0.258). High ISQ values were found in both groups at each time point. Conclusions NH implants are a viable alternative to SA surface, as they seem to avoid the ISQ drop during the remodeling phase.

Randomized Controlled Clinical Trial of All-Ceramic Single-Tooth Implant Reconstructions Using Modified Zirconia Abutments: Results at 5 Years After Loading

The objective of this trial study was to assess whether submucosal veneering of internally connected zirconia abutments influences clinical, radiographic, and technical outcomes of single-tooth implant-borne reconstructions at 5 years after loading. A total of 20 patients with 20 single-tooth implants in the anterior or premolar area of the maxilla or mandible were included. The implants were randomly restored with fixed single-tooth reconstructions using either pink-veneered customized zirconia abutments (test group = 10) or nonveneered customized zirconia abutments (control group = 10). All reconstructions were adhesively cemented with all-ceramic crowns. Follow-up examinations were performed at baseline (7 to 10 days after crown insertion) and at 1, 3, and 5 years after loading, at which points the following were assessed: periodontal parameters such as probing depth (PD), bleeding on probing (BOP), and marginal bone levels, as well as technical outcomes using the modified United States Public Health Service (USPHS) criteria. Statistical comparisons were based on the Wilcoxon-Mann-Whitney test. Sixteen patients attended the 5-year follow-up. At 5 years, the implant survival rate was 100% and the prosthetic survival rate was 94.1% (one abutment fracture in the test group). Veneering of the submucosal part of zirconia abutments resulted in significantly higher mean PD values: 3.6 ± 0.4 mm (test group) and 3.0 ± 0.5 mm (control group), P = .042. Marginal bone levels at 5 years and changes up to 5 years were not significantly different between groups (P > .05). One crown exhibited an abutment fracture and two crowns a minor chipping (17.6% overall technical complication rate). Limited by a small sample size, veneering of the submucosal part of internally connected zirconia abutments led to outcomes that were less favorable biologically (PD, BOP, and KM), but similar to nonveneered abutments radiographically and technically.

All-ceramic versus titanium-based implant supported restorations: Preliminary 12-months results from a randomized controlled trial.

PURPOSEThe aim of the present randomized controlled study was to compare prefabricated all-ceramic, anatomically shaped healing abutments followed by all-ceramic abutments and all-ceramic crowns and prefabricated standard-shaped (round-diameter) titanium healing abutments followed by final titanium abutments restored with porcelain-fused-to-metal (PFM) implant crowns in the premolar and molar regions.MATERIALS AND METHODSForty-two patients received single implants restored either by all-ceramic restorations (test group, healing abutment, final abutment, and crown all made of zirconia) or conventional titanium-based restorations. Immediately after prosthetic incorporation and after 12 months of loading, implant survival, technical complications, bone loss, sulcus fluid flow rate (SFFR) as well as plaque index (PI) and implant stability (Periotest) were analyzed clinically and radiologically.RESULTSAfter 12 months of loading, an implant and prosthetic survival rate of 100% was observed. Minor prosthetic complications such as chipping of ceramic veneering occurred in both groups. No statistical significant differences were observed between both groups with only a minimum of bone loss, SFFR, and PI.CONCLUSIONAll-ceramic implant prostheses including a prefabricated anatomically shaped healing abutment achieved comparable results to titanium-based restorations in the posterior region. However, observational results indicate a benefit as shaping the peri-implant soft-tissue with successive provisional devices and subsequent compression of the soft tissue can be avoided.

Multicenter Retrospective Analysis of Implant Overdentures Delivered with Different Design and Attachment Systems: Results Between One and 17 Years of Follow-Up.

Purpose: To analyze implant and prosthetic survival rates, complications, patient satisfaction, and biological parameters of patients rehabilitated with implant overdentures (IOV) on splinted and nonsplinted implants and different attachment systems, in function for one to 17 years. Methods: This retrospective study evaluated data collected from patients rehabilitated with implant overdentures between January 2001 and December 2016 in nine different centers. Outcome measures were implant and prosthetic success rates, mechanical complications, marginal bone loss (MBL), oral health impact profile (OHIP), bleeding on probing, and plaque index. Results: A total of 581 implants were installed in 194 patients. Patients were followed for a mean period of 60.6 months (range 6–206). Eighty-nine patients received 296 low profile attachment (OT Equator), 62 patients received 124 ball attachments, and 43 patients received 107 Locator attachments. In eighty-three patients the implants were splinted with computer aided design/computer aided manufacturing (CAD/CAM) or casted bar. At the last follow-up, 10 implants failed in eight patients. Statistical significance was found for failed prostheses (P = 0.0723) and complications (P = 0.0165), with better values for splinted implants. No statistically significant differences were found in proportion of implant and prosthetic failure (P > 0.05). At a five-year follow-up, proportion of complications (P = 0.0289) and failed prostheses (P = 0.0069) were statistically higher for IOV on Locator attachments. No difference was founded in MBL at one- and two-year follow-up between different attachment systems (P > 0.05). Statistically significant improvement in all the OHIP categories was reported in all the patients, after one year of function. Conclusions: Implant overdenture showed high implant and prosthetic survival rates, low complications, high patient satisfaction, and good biological parameters in the long-term follow-up. Splinting the implants may reduce number of mechanical complications. Locator attachments showed higher number of complications. Further studies are needed to confirm these preliminary results.

Bilateral, Simultaneous Total Knee Replacement (TKR) Surgery for Hemophilia a with Eloctate (Extended Half Life Product)—A Feasible and Cost Effective Approach

Abstract INTRODUCTION: The majority of bleeds experienced by people with Haemophilia occur into the joints or muscles.The joints most frequently involved are the knees, ankles, and elbows. The consequences of recurrent bleeding into a joint leads to chronic hemophilic arthropathy. Knee arthropathy is crippling situation affecting Quality of Life (QOL) for Patient with Hemophilia (PWH).With the advent of the availability of Clotting Factor Concentrates (CFC), Total Knee Replacement (TKR) can now be performed safely. TKR is performed using Total 2000IU/kg of Plasma Derived (PD) or Recombinant CFC. Literature recommends 1000-1200IU/kg of Total Eloctate for TKR. METHODS: Aim for feasible, safe &amp; cost effective CFC replacement policy for TKR 1) Use lower dose Eloctate during TKR 2) Perform Simultaneous Bilateral TKR Patients and Methods: Total 24 Severe Hemophilia A patients underwent 48 bilateral, simultaneous TKR. Age range was 28-51 years. Pre-operative 50IU/Kg Eloctate was infused. Pre-operative FVIIIc Level was median 108IU/kg (86-126 IU/dl). Post-operative Eloctate replacement was 40-50IU/kg once daily till day 5, then 30IU/kg once daily till Day15. FVIIIc assay was monitored at least once daily till day 10. Dose was tailored according to FVIIIc levels. Trough FVIIIc level was maintained above 60iu/dl for first 5 days. Average duration of surgery was 4 hours. Drains were removed after 48 hours. LMWH Thromboprophylaxis &amp; physiotherapy was started from post-operative Day 2. Clips were removed on Day 14. Eloctate was received through Humanitarian Aid Program of WFH. RESULTS: Total of 48 bilateral, simultaneous TKR were performed on 24 patients. 23 patients had no significant intra or post-operative bleeding &amp; no transfusion support was needed . One patient underwent pseudo tumour excision and TKR in the same sitting &amp; required extra 50IU/kg Eloctate+ 8 packed red cells + 8 FFP + 10 Cryoprecipitate intra operative during excision of Pseudo Tumour for total blood loss of 2200 ml as expected . He also experienced no post-operative bleeding till discharge. No wound or prosthesis infection was noted. Prosthesis survival was 100%. Total Eloctate used was 510- 640 IU/kg over 14 days. DISCUSSION: There was no excess bleeding in our patients. The results from our assessment are quite similar to the overall prosthetic survival rates reported for TKAs performed on patients without hemophilia.In our study there were no periprosthetic infections reported. Other studies have showed rates of periprosthetic infection after primary TKA in patients with hemophilia are much higher (up to 11%). Late infection is a major concern after TKA in patients with hemophilia, an important factor is the high rate of HIV-positive patients (3).Another important complication of TKA surgery is aseptic loosening of the prosthesis. Aseptic loosening was not found in any of our patients. Rates of this complication increase over follow-up (4). In our data the ROM improved and flexion contracture reduced significantly after arthroplasty following the scheduled physiotherapy.As mentioned in an article by Schild FJA et al the Median amount of CFC (Plasma derived &amp; recombinant) used for multi-joint procedure per patient was 57,680 IU; in another retrospective study by A Thes et al where the median CFC (Plasma derived &amp; recombinant) usage per patient was 1,500 IU/kg; whereas we used Total Eloctate of 510- 640 IU/kg and hence reduced CFC usage compared to western protocol. CONCLUSIONS : Low dose Eloctate replacement is safe and cost effective for TKA in PWH. Bilateral TKA in same sitting is feasible and increases cost effectiveness in PWH. Thrombo-prophylaxis with LMWH can be done safely in PWH. Bleeding events did not increase with low dose Eloctate &amp; LMWH. At these doses, total Eloctate replacement was 40-50% lower than previously reported for TKR surgery for PWH. Our protocol offers a cost effective and safe option in resource constraint countries. Disclosures No relevant conflicts of interest to declare.

Multicenter retrospective analysis on survival rate, complications, patient satisfaction and biological parameters of implant overdentures delivered with different design and attachment systems‐ results between 1 and 17 years of follow‐up

Background Edentulism can lead to significant functional impairment and psychological changes in patients. The conventional method for treating edentulism is to provide complete dentures. An implant overdenture may improve oral function and patient satisfaction compared with a conventional complete denture. Nevertheless, evidence is lacking about the number of implants, prosthetic design and type of attachments. Aim/Hypothesis To report implant and prosthesis survival rates, complications, patient satisfaction, and biological parameters of patients rehabilitated with an implant overdentures on splinted and non-splinted implants and different attachment systems, in function for a mean period of 5 years (1–17 years) Material and Methods The present retrospective multicenter study evaluated data collected from fully or partially edentulous patients rehabilitated with an implant overdenture between January 2001 and December 2016 in 9 different centers. The outcome measures were implant and prosthetic success rates, mechanical complications, oral health impact profile, marginal bone loss, bleeding on probing and plaque index. Results A total of 581 implants were installed in 194 patients, followed for a mean period of 60.6 months (range 6-206). Sixty-nine patients were rehabilitated in the maxilla+ while, 125 patients in the mandible. Eight-nine patients received 296 OT Equator attachments, 62 patients received 124 ball attachments, and 43 patients received 107 Locator attachments. In eighty-two patients the implants were splinted. At the last follow-up, 10 implants (1.7%) failed in 8 patients (4.1%). At 5-year follow-up, proportion of complications was statistically higher for not splinted overdenture (P = 0.0171). No statistically significant differences were founded in proportion of implant and prosthetic failure (P>. No difference between overdenture on splinted and not splinted implants for HOIP, MBL, BoP, PI at each time points, up to 5 years on function (P > 0.05). At 5-year follow-up, proportion of complications (P = 0.0289) and failed prostheses (P = 0.0069) were statistically higher for IOV on Locator attachments Conclusions and Clinical Implications Implant overdenture showed high implant and prosthetic survival rates, low complications, high patient satisfaction, and good biological parameters in the long term follow-up. Splinting the implants may reduce number of mechanical complications. Locator attachments showed higher number of complications. Further studies are needed to confirm these preliminary results.

Short-term report of an ongoing prospective cohort study evaluating the outcome of full-arch implant-supported fixed hybrid polyetheretherketone-acrylic resin prostheses and the All-on-Four concept.

More research is needed on the study of new materials for fixed prosthetic implant-supported rehabilitations. The purpose of this study was to report the short-term outcome of full-arch implant-supported fixed hybrid polyetheretherketone (PEEK)-acrylic resin prostheses and the all-on-four concept. This prospective cohort clinical study included 37 patients (29 women, eight men) with an average age of 60 years (range: 38-78 years) with 49 full-arch hybrid PEEK-acrylic resin prosthesis supported by implants through the all-on-four concept. Primary outcome measures were prosthetic survival. Two patients with two maxillary prostheses were lost to follow-up. One patient with a double full-arch rehabilitation fractured the mandibular PEEK framework, rendering a 98% prosthetic survival rate. No implants were lost. The average (SD) marginal bone remodeling after 1 year of follow-up was 0.37 mm (0.58 mm). Technical complications concerning the veneer adhesion occurred in six patients and were resolved in all patients (with exception of the patient with prosthetic failure) through the creation of mechanical retentions and changing the bonding primer. Mechanical complications occurred in three patients and five prostheses consisting in prosthetic screw loosening (n = 2 patients) and fracture of the acrylic resin teeth (the patient with a prosthetic failure). Within the limitations of this study, the results suggest that hybrid polymer (PEEK)-acrylic resin prostheses supported by implants for full-arch rehabilitation may represent a valid treatment option, still requiring longer-term validation.

Clinical and Radiographic Evaluation of Short Implants Placed in the Posterior Mandible: A 1-Year Pilot Split-Mouth Study.

In many cases, due to anatomical limitations, the placement of regular-length implants cannot be facilitated without the performance of advanced surgical procedures. However, these are associated with morbidity, prolonged treatment time, and costs. To overcome such disadvantages, short implants were introduced. The aim of this prospective pilot split-mouth study was to compare the clinical outcome between short implants (7 mm) and regular-length (≥10 mm) implants placed in the posterior mandible after 1 year of prosthetic delivery. Ten patients received 4 implants in the posterior mandible. Two short implants were placed in one side and 2 regular-length implants were placed contralaterally. These were restored by means of splinted screw-retained metal-ceramic crowns. Marginal bone loss (MBL) and soft-tissue parameters were compared. No implant failed. Both types of implants showed success rates of 90% and survival rates of 100%. From prosthetic delivery to 1 year post-loading a bone gain of +0.29 mm for short implants and +0.19 mm for regular-length implants was present without showing any statistically significant differences in MBL between the 2 implant types ( P > .05). Bleeding on probing, clinical attachment level, probing depth, and crown-to-implant ratio did not show any statistically significant differences between the 2 implant lengths ( P > .05). One case of chipping occurred in the regular-length implant group, leading to a prosthetic survival rate of 95%. Short implants showed a prosthetic survival rate of 100%. After 1 year, short implants showed comparable clinical outcomes to that of regular-length implants, making them a viable treatment option in the posterior mandible.

Complete-arch Implant-supported Composite Pressed Restorations Fixed Dental Prostheses

The aim of this study was to evaluate the clinical performance of the composite pressed on metal framework for full-arch implant-supported fixed prosthesis in order to eliminate the drawbacks related to the chipping of porcelain fused to metal or to zirconia restorations. Sixteen patients received 22 implant-supported screw-cement-retained complete-arch restorations, consisting of composite pressed restorations. All patients were follow-up visit up to 2 years on function (range 24 to 30 months, mean 28.3 months). The outcomes were implant and prosthetic survival rates and calculations of wear determination (mm). After two years of function, the wear values were 95.54�6.88 mm on pressed composite restoration. Using composite pressed restorations appears to be a predictable, esthetic and successful treatment option for method of full arch restorations over implants.

Double Guided Surgery in All-on-4® Concept: When Ostectomy Is Needed.

Background The rehabilitation of edentulous jaws with guided and flapless surgery applied to the All-on-4 concepts is a predictable treatment with a high implant and prosthetic survival rates, but there are several contraindications for this technique like when bone reduction is needed due to a high smile line in the maxilla or when there is an irregular or thin bone crest. Purpose To report a technique with double guided surgery for bone reduction and implant placement with the All-on-4 concept. Materials and Methods 7 patients were included in the study. Guided implant planning was performed using CBCT, and the virtual templates were created with three dedicated software. Custom surgical templates were made for the ostectomy and for implants positioning. Results 28 implants were placed using a double bone-supported surgical guide. The mean angular errors between the preoperative-planned implant and the postoperative-placed implant were 2.155° ± 2.03°; the mean distance errors between the planned and the placed implants were 0.763 mm ± 0.55 mm on the shoulder implant and 0.570 mm ± 0.40 mm on the apex implant. Conclusions The results of our study indicate that this treatment is predictable with an excellent survival rate allowing excellent results even when bone reduction is mandatory.

Prefabricated Bar System for Immediate Loading in Edentulous Patients: A 5-Year Follow-Up Prospective Longitudinal Study

Objectives The aim of this clinical study was to evaluate a new type of prefabricated bar system, supported by axial and tilted implants at 5-year follow-up. Materials and Methods Twenty-nine consecutive participants (19 females, 10 males) (mean age 61.4 years), edentulous in one or both jaws, with severe atrophy of the posterior regions, were treated according to the All-on-four® protocol with immediately loaded axial (64) and tilted (64) implants supporting complete-arch screw-retained prostheses (12 maxillary, 20 mandibular) featuring a prefabricated bar as framework. Follow-up visits were performed at 3, 6, 12, 24, 48, and 60 months after implant insertion. Radiographic assessments were made using panoramic radiographs obtained immediately after surgery and at each follow-up visit. Bone level measurements around the axial and tilted implants were compared by means of the Student's t-test. Results One axial implant failed in the lower jaw and did not compromise prosthetic function. The 60-month overall implant survival rate was 100% for axially positioned implants and 98.44% for tilted implants. The implant survival rates were 100% in the maxilla and 98.75% in the mandible. None of the 32 fixed prostheses were lost during the observation period, representing a prosthetic survival rate of 100%. No statistically significant differences (P > 0.05) in marginal bone loss between tilted and axial implants were detected in either jaw over time. Conclusions The use of the evaluated prefabricated bar for immediately loaded implants placed according to the All-on-four concept may significantly reduce implant failures; however, more long-term prospective clinical trials are needed to affirm the effectiveness of the surgical-prosthetic protocol.

Primary Hemiarthroplasty Following Severe Proximal Humerus Fracture Dislocations with Irretrievable Humeral Head in Young Patients

Neer first popularised the use of primary hemiarthroplasty to treat complex proximal humerus fractures, especially when the humeral head is nonviable or not reconstructable with internal fixations, and with younger patients. A 16-year-old boy had a motor vehicle accident and sustained a closed right proximal humerus fracture dislocation without neurovascular injury. Intraoperatively, due to difficulty retrieving the humeral head which dislocated and positioned behind the clavicle, hemiarthroplasty was done to avoid injuring the brachial plexus, vessels and lung. Mr Y, a 34-year-old man similarly sustained closed left proximal humerus fracture dislocation with an irretrievable head. He too underwent hemiarthroplasty. Both patients were followed up for a year with no pain and fairly good range of movement and muscle power. In complex proximal humerus fractures, there is still debate regarding primary hemiarthroplasty. There are risks of secondary displacement of fracture fragments and head necrosis after internal fixation. Neer and Cofield reported over 90% patients had relief of pain and 66% patients had free range of movement post hemiarthroplasty. Other authors described primary malposition and subsequent migration or deficient osseous integration as a complication after prosthesis. In a thirteen-year observational cohort study of 163 patients with hemiarthroplasty, the overall rate of prosthetic survival was 96.9% at one year, 95.3% at five years, and 93.9% at ten years. Of the factors that were assessed, the age is most important due to factors such as degenerative changes in the rotator cuff, osteoporosis, and motivation to achieve a good range of motion. Successful treatment of acute proximal humerus fractures with prosthetic replacement is challenging to orthopaedic surgeons as it requires proper patient evaluation, good surgical technique, especially in soft-tissue tensioning and stability, and meticulous rehabilitation. In young patients with good bone quality and irretrievable head, hemiarthroplasty is a choice.

Use of Intraoral Welding to Increase the Predictability of Immediately Loaded Computer-Guided Implants.

Inaccuracy of computer-guided implant placement may lead to complications when combined with an immediately loaded prefabricated prosthesis. The aim of this case series was to describe the use of an intraoral welding technique to increase the predictability of immediately loaded implants supporting a fixed full-arch prosthesis after computer-guided flapless implant placement. A total of 60 Ankylos plus implants (Dentsply) with a width of 3.5 mm and a length of 8 to 14 mm were placed consecutively in 10 patients. The implants were functionally loaded using the intraoral welding technique on the day of surgery. The accuracy of guided implant placement was assessed by matching the planning cone beam computed tomography (CBCT) scans with postoperative CBCT scans. No mechanical or biologic complications were registered at the 1-year follow-up. The global coronal deviation of implant placement from the guide plan ranged from 0.25 to 2.84 mm (SD: 0.6 mm), with a mean of 1.28 mm. Average angle deviation was 3.42 degrees (range 0.38-7.82 degrees; SD: 1.52 degrees). The global apical deviation ranged between 0.36 and 3.85 mm (SD: 0.71 mm), with a mean of 1.65 mm. Despite the inaccuracy registered, this guided-welded approach allowed successful achievement of a passive fit of the full-arch prosthesis on the inserted implants the same day of the surgery and provided a high implant and prosthetic survival rate at the 1-year follow-up.

Immediate full-arch rehabilitation of the severely atrophic maxilla supported by zygomatic implants: a prospective clinical study with minimum follow-up of 6 years

The aim of this study was to evaluate the outcomes of immediate full-arch prostheses supported by zygomatic implants alone or in combination with standard fixtures after a minimum of 6 years of loading. From October 2008 to April 2010, 15 patients with severely atrophic maxillae were treated using four zygomatic implants or two zygomatic implants in conjunction with two conventional fixtures. All subjects received a fixed screw-retained prosthesis within 3hours of surgery, while the final restoration was delivered after 6 months. Follow-up examinations were scheduled to evaluate zygomatic implant survival, conventional dental implant success, prosthetic success, plaque and bleeding scores, marginal bone loss for conventional dental implants, and patient satisfaction. Forty-two zygomatic fixtures and 18 standard implants were placed. Patients were followed up for a minimum of 79 months (range 79–97 months, average 90.61 months). No implant was lost, leading to implant and prosthetic survival rates of 100%. Bone loss for conventional implants averaged 1.39±0.10mm after 6 years of function, leading to a 100% implant success rate. High levels of patient satisfaction were recorded. These medium-term results indicate that immediate full-arch rehabilitation supported by zygomatic implants could be considered a viable treatment modality for the severely atrophic maxilla.

Randomized controlled clinical trial comparing one-piece and two-piece dental implants supporting fixed and removable dental prostheses: 4- to 6-year observations.

To test whether or not a one- (S1) and a two-piece (S2) dental implant systems render the same biological, technical, and esthetic outcomes regarding implants and implant-supported reconstructions over an observation period of 4 to 6years. Sixty patients were randomly assigned to receive S1 or S2 implants. The implants were restored with either fixed or removable prostheses. The insertion of the final reconstruction was chosen as baseline. One-year and 4- to 6-year (FU-5) measurements included biological (e.g. marginal bone level, probing pocket depth, peri-implant mucositis, and peri-implantitis), technical (e.g. fracture or loosening of prosthetic screws, fracture or loosening of abutments, fracture of framework, and/or veneering ceramic (minor, major), loss of retention for cemented restorations), and esthetic parameters (visibility of the crown margin, shimmering of the implant through the mucosa, the level of the facial margo mucosae compared to the contralateral tooth or implant site and the modified papilla index) for implants and reconstructions. Survival and success rates of implants and reconstructions were calculated. Because of the asymmetric data distributions, nonparametric statistical methods were applied. The implant-based analysis revealed a cumulative implant survival rate of 97.9% (S1: 96.6%; S2: 98.9%) at FU-5. The median marginal bone level for group S1 changed from 0.51mm at baseline to 0.49mm at FU-5 and for group S2 from 1.02mm to 1.35mm (P<0.001). Patient-level analyses demonstrated a frequency of peri-implant mucositis of 7.7% (S1) and 10.0% (S2) and for peri-implantitis of 7.7% (S1) and 13.3% (S2) at FU-5. The patient-based cumulative implant survival rate was 94.6% (S1: 92.3%; S2: 96.7%). The overall patient-based biological complication rate amounted to 15.4% (S1) and to 23.3% (S2) (P=0.517), whereas the overall technical complication rates were 30.8% (S1) and 13.3% (S2) (P=0.349). The prosthetic survival rates were 93.1% for S1 and 100% for S2 (P>0.05). Both implant systems reveal high survival rates on the implant and prosthetic level. Apart from marginal bone-level changes, biological and technical outcomes did not reveal significant differences between the two implant systems.

Reemplazo Total de Rodilla en pacientes menores de 55 años de edad con gonartrosis Seguimiento de 2 a 13 años. [Total Knee Arthroplasty for gonarthrosis in patients 55 years old or younger. 2-13 years follow-up.

&lt;p&gt;&lt;strong&gt;Introducción&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;&lt;strong&gt;&lt;/strong&gt;El número de reemplazos totales de rodilla (RTR) en pacientes jóvenes continua en aumento. La literatura muestra resultados contradictorios y la mayoría incluyen pacientes con Artritis Reumatoide (AR). El propósito de este estudio fue analizar un grupo de RTR en menores de 55 años, excluyendo pacientes con AR, evaluando la sobrevida protésica, las fallas radiológicas y sus resultados funcionales.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Materiales y Métodos&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;&lt;strong&gt;S&lt;/strong&gt;e analizaron retrospectivamente 53 RTR en 46 pacientes, con una edad promedio de 49 (26-54) años y un seguimiento promedio de 6,5 (2-15) años. Los diagnósticos preoperatorios correspondieron a 46 gonartrosis idiopáticas, 5 postraumáticas y 2 osteonecrosis.&lt;strong&gt; &lt;/strong&gt;22 presentaban antecedentes de cirugías previas. Se utilizaron 49 implantes importados y 4 nacionales. Los resultados clínico-funcionales se objetivaron mediante Knee Society Score y WOMAC, mientras que para la evaluación radiológica se utilizo el sistema de la Knee Society.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Resultados&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;&lt;strong&gt;&lt;/strong&gt;La puntuación funcional del KSS mejoró de 49,3 a 92,6 en promedio, mientras que la puntuación propia de rodilla paso de 46,8 a 91,4 puntos en el posoperatorio. La puntuación WOMAC en promedio fue de 2,3 para dolor, 2,6 para rigidez y 27,3 para la capacidad funcional. El 16% presento líneas de radiolúcidas &amp;lt;1mm que no progresaron en el tiempo. Hubieron 3 infecciones que requirieron de una revisión en dos tiempos evolucionando favorablemente y 4 rigideces que fueron tratadas mediante movilización artrocópica. La sobrevida protésica fue del 94,34%.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusiones&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;&lt;strong&gt;&lt;/strong&gt;El RTR en pacientes &amp;lt;55 años mostró ser un procedimiento confiable en lo que respecta a la mejora de la función, con una aceptable sobrevida protésica teniendo en cuenta los antecedentes quirúrgicos previos. No observamos fallas radiológicas al final del seguimiento.&lt;/p&gt;