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Purpose: To compare the clinical outcomes of single implants with titanium (Ti) or zirconia (Zr) abutments after up to 5 years in function.Materials and Methods: This study was a retrospective analysis on single implants with screw-retained abutments (Zr or Ti) covered with porcelain veneer placed between 2011 and 2013 at one referral specialist clinic. Clinical data from patient records were collected from 132 patients and 174 implants. Technical complications such as fractures, chipping, and abutment screw loosening were registered. Radiographs were analyzed comparing both annual bone loss and accumulated bone loss at 5 years. In 57 patients with 85 implants, the values of accumulated bone loss at 5 years were compared to baseline.Results: Technical complications occurred in 16 (9%) of the implants, most often during the first year. The following complications were found: fracture of the abutment (n = 1); loosening of the abutment screws (n = 5); and chipping of the porcelain veneer (n = 11). Ti abutments had more complications than Zr abutments (79%). Of all the implants, 45% had an annual bone loss ranging between 0.05 and 2.15 mm, and 59% had an accumulated bone loss at 5 years ranging between 0.05 and 4.25 mm. Zr abutments had a statistically significantly higher amount of yearly and accumulated bone loss at 5 years.Conclusion: Abutment material affected marginal bone loss. The Zr group displayed statistically more bone loss both yearly and after 5 years compared to the Ti group. Technical complications were not affected by abutment material but were affected by age of the patient. [ABSTRACT FROM AUTHOR]

Purpose: Knowledge of the early mortality patterns in edentulous implant patients is limited. This study aimed to report patient mortality within the first year after surgery and compare the cause of death with preexisting conditions reported before surgery. Materials and Methods: In this retrospective cohort study, data from the Swedish National Death Register on patients, consecutively treated in the edentulous arch between 1986 and 2013, were compared with information from the patient files regarding the preexisting health conditions of the deceased patients. One-year survival rates were calculated and compared with expected mortality in a Swedish reference population based on three age groups: young (< 45 years of age), middle-aged (45 to 64 years of age), and old patients (> 64 years of age). Proportions of mortality between study groups and reference populations were tested by means of a log-rank test, and agreement between diagnoses before surgery and cause of death was tested by means of kappa test. Results: Altogether, 3,877 patients were included, of whom 60 patients died within 1 year after implant surgery (1.5%). The expected mortality in the Swedish reference population was 2.1% (P < .05). Mortality was higher for middle-aged (P = .02) but lower for old patients (P = .0001) compared with the Swedish reference populations. Eight of the deceased patients (13%) had no preexisting conditions, while 48 patients reported a health diagnosis before implant surgery. The most common of these were related to the circulatory system (ICD 10-I), which was the cause of death for 30 patients. A “none to slight agreement” between presurgical diagnoses and cause of death was observed in the population (kappa: 0.152). Conclusion: Edentulous implant patients presented overall lower mortality than expected in the general population during the first year after surgery. However, middle-aged patients showed a higher proportion of deceased patients compared with control people of the same age. Cardiovascular diseases were the cause of death in 50% of the group, and the agreement between presurgical and cause of death diagnoses was poor. [ABSTRACT FROM AUTHOR]

Purpose: To investigate direct bonding of a 10-MDP-based cement to two novel translucent yttria-stabilized tetragonal zirconia polycrystal ceramics (4Y-TZP, 5Y-TZP) and observe the influence of thermocycling on this bonding. Materials and Methods: Powders of presintered and isostatically pressed 5Y-TZP, 4Y-TZP and 3Y-TZP were mixed with a 10-MDP-based cement (Panavia F 2.0), then stored in deionized water for 48 h at 37°C or thermocycled 10,000 times. Raman spectroscopy and Fourier-transform infrared spectroscopy were used to assess the presence of a functional group (PO32-) that could indicate bonding before and after thermocycling. X-ray photoelectron spectroscopy was used to identify the presence of the suspected Zr-O-P bond in the same specimens. A shearbond strength (SBS) test was conducted based on ISO 29022:2013. Results: Marked peaks assigned to the asymmetric vibrations of the PO32- functional group were observed in both zirconias before and after thermocycling. The binding energy corresponding to Zr-O-P interactions (531.5 eV) was masked by the aluminosilicate in the filler of the cement. Shear bond strengths were approximately 20 MPa after water storage and approximately 6 MPa after thermocycling. No differences were found between the control group and the translucent zirconias. Conclusion: Direct bonding of the 10-MDP-based cement to both 4Y-TZP and 5Y-TZP was highly plausible. Both 4YTZP and 5Y-TZP may be promising alternatives to glass-ceramic restorations. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to evaluate the fit of additively manufactured cobalt-chromium and titanium and CNC-milled titanium frameworks before and after ceramic veneering. Materials and Methods: Ten stone casts simulating an edentulous maxilla provided with six abutment analogs were produced. For each stone cast, one additively manufactured cobalt-chromium framework (AM CoCr) and one titanium framework (AM Ti) were fabricated. The fit was analyzed with a coordinate measuring machine in three dimensions (x, y, and z axes) using best-fit virtual matching of center point coordinates, before and after ceramic veneering. CNC-milled titanium frameworks (CNC Ti) and earlier results from CNC-milled cobalt-chromium frameworks (CNC CoCr) were used for comparison. Results: All frameworks presented minor misfit before and after veneering in the horizontal plane (x- and y-axes) between 2.9 and 13.5 μm and in the vertical plane (z-axis) between 1.6 and 5.4 μm. Ceramic veneering affected the fit of all groups of frameworks. Both AM Ti and AM CoCr presented significantly smaller distortion in the vertical plane compared with the CNC-milled frameworks. Conclusion: Implant-supported frameworks can be produced in either Ti or CoCr using either CNC milling or additive manufacturing with a fit well within the range of 20 μm in the horizontal plane and 10 μm in the vertical plane. The fit of frameworks of both materials and production techniques are affected by the ceramic veneering procedure to a small extent [ABSTRACT FROM AUTHOR]

Purpose: The literature shows that the performance of densely sintered zirconia single crowns seems to be unaffected by the cement material. The purpose of this study was to evaluate the effects of various cement materials on the stress distribution in a monolithic translucent zirconia crown.Materials and Methods: A crown-cement-dentin complex was modeled. Six cements were evaluated: zinc phosphate, glass-ionomer, resin-modified glass-ionomer, dual-cure resin, calcium aluminate-based, and a theoretical or conceptual cement with mechanical properties close to those of dentin (ie, monoblock cement).Results: While varying stress concentrations were found within the cements, the stress concentrations in the crown and dentin were consistent irrespective of cement material.Conclusion: Within the limitations of this study, it can be concluded that cement material had a negligible effect on stress distribution in the monolithic zirconia crown. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to report the distribution of patients with early implant failures after implant treatment in the edentulous jaw with regard to age at surgery and association with patient mortality over a 15-year period.Materials and Methods: All consecutively treated patients treated in the edentulous jaw at a single specialist clinic from 1986 to 1997 were included and followed up for 1 year for implant failures and for 15 years with regard to patient mortality. Patients were arranged into age groups, and life tables for patients and reference groups of patients with comparable age (based on national population data) were calculated. Log rank test was used to test differences in patient survival between those with reported early implant failures and those with no early failures. Mantel-Haenszel chi-square test was used to test association between proportions of implant failures and age groups.Results: A total of 55 patients were excluded because they were not living in Sweden (nonresidents/emigrated). Altogether, 2,566 patients were included, with a mean age of 65 years (SD: 11). Of these, 988 patients were deceased during the 15 years of follow-up (38%), and 291 presented an early implant failure (11.3%), most of them before prosthesis placement (72%). Patients with early implant failures presented higher mortality rates than patients with no failures (P < .05), and failure rates decreased consistently from younger to higher age groups (P < .05).Conclusion: Patients in the younger age groups showed an increased mortality compared with the reference group (P < .05) and a higher prevalence of early failures compared with older patients (P < .05). Older patients showed an opposing pattern of lower mortality compared with reference groups of comparable age (P < .05), but both younger and older patients with early failures showed a higher mortality compared to patients with no failures (P < .05). [ABSTRACT FROM AUTHOR]

Purpose: Little is known about the relationship between implant patient mortality compared to reference populations. The aim of this study was to report the mortality pattern in patients treated with dental implants up to a 15-year period, and to compare this to mortality in reference populations with regard to age at surgery, sex, and degree of tooth loss.Materials and Methods: Patient cumulative survival rate (CSR) was calculated for a total of 4,231 treated implant patients from a single clinic. Information was based on surgical registers in the clinic and the National Population Register in Sweden. Patients were arranged into age groups of 10 years, and CSR was compared to that of the reference population of comparable age and reported in relation to age at surgery, sex, and type of jaw/dentition.Results: A similar, consistent, general relationship between CSR of different age groups of implant patients and reference populations could be observed for all parameters studied. Completely edentulous patients presented higher mortality than partially edentulous patients (P < .05). Furthermore, implant patients in younger age groups showed mortality similar to or higher than reference populations, while older patient age groups showed increasingly lower mortality than comparable reference populations for edentulous and partially edentulous patients (P < .05).Conclusion: A consistent pattern of mortality in different age groups of patients compared to reference populations was observed, indicating higher patient mortality in younger age groups and lower in older groups. The reported pattern is not assumed to be related to implant treatment per se, but is assumed to reflect the variation in general health of a selected subgroup of treated implant patients compared to the reference population in different age groups. [ABSTRACT FROM AUTHOR]

Purpose: Implant treatment using osseointegrated implants has been performed for more than 40 years, but limited knowledge is available on how treatment outcomes have changed over time. The aim of this study was to report and compare the prosthetic treatment outcomes from two patient cohorts provided with fixed implant prostheses in the edentulous maxilla between 1986 and 1987 (early) and 2001 to 2004 (late) at the same clinic.Materials and Methods: The two groups of patients comprised 76 and 109 edentulous patients consecutively provided with 450 and 670 Branemark System implants and fixed screw-retained prostheses, respectively. Both groups were followed for 5 years with regard to prosthetic treatment, clinical maintenance, and complications.Results: Altogether, 37 patients (20%) were lost to follow-up during the 5 years, and more patients were noncompliant in the late group (P < .05). Prosthetic treatment was performed using significantly less chair time in the late group (P < .05), and 22 and 68 patients were followed for 5 years without any reported complications in the early and late groups, respectively (P < .05). The 5-year prosthesis cumulative survival rate was 97.1% in the early group and 100.0% in the late group. Patients in the late group presented fewer problems with diction and veneer fractures, and fewer patients had their prostheses temporarily removed for adjustments (P < .05).Conclusion: Prosthetic treatment and maintenance of implant-supported fixed prostheses improved significantly between the groups. Int J Prosthodont 2011;24:356-362. [ABSTRACT FROM AUTHOR]

Purpose: Implant treatment has been performed for more than 45 years, but there is still limited knowledge on how treatment outcomes are changing over time. The aim of this study was to report and compare the treatment outcomes of two patient cohorts from the same clinic, rehabilitated with fixed implant prostheses in the edentulous maxilla between 1986 and 1987 (early) and 2001 to 2004 (late).Materials and Methods: The early group included 76 edentulous patients who were consecutively provided with 450 turned Branemark System implants; the late group included 109 edentulous patients provided with 360 turned and 310 TiUnite Branemark System implants. Both groups were followed and evaluated clinically and radiographically for 5 years according to similar protocols.Results: Altogether, 37 patients (20%) were lost to follow-up over 5 years; more patients were noncompliant in the late group (P < .05). The 5-year overall implant cumulative survival rates were 93.4% and 97.3% for the early and late groups, respectively. In the early group, significantly more turned implants failed before prosthesis insertion compared to the outcome of TiUnite implants in the late group (P < .05). Mean bone loss was comparable for the early and late groups during the 5 years of follow-up (0.5 ± 0.46 and 0.7 ± 0.76 mm, respectively), but more patients presented at least 1 implant with more than 2 mm of bone loss during the follow-up period in the late group (P < .05). Mucosal hyperplasia and inflammation showed a trend of higher frequency at implants in the early group of patients (P > .05).Conclusion: Implant treatment was more predictable before loading in the late group of patients, related to the change in the implant surface (P < .05). On the other hand, it was observed that the prevalence of patients with more bone loss at at least 1 implant (> 2 mm) was higher in the late group (P < .05). This could possibly be attributed to a more bioactive implant surface and shorter healing period before implant surgery in the late group. Int J Prosthodont 2011;24:345-355. [ABSTRACT FROM AUTHOR]