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Background Several studies have reported the efficiency of immediate loading techniques. Purpose The aim of this multicenter prospective study was to evaluate the clinical efficiency of the one-piece screw ( OPS) implants used by general dentists. Materials and Methods A total of 272 patients were treated with 533 implants at five dental clinics by five general dentists. Some implants were provided with provisional restoration. Implants in partially edentulous spaces were splinted with acryl, composite, and intraoral welding. The implant survival rates, bone resorption, plaque accumulation, and soft tissue health were evaluated after 3, 6, and 12 months. The final restorations were cemented in the maxilla after 6 months and in the mandible after 3 months. Results Twelve implants failed (98% survival rate) after 12 months. None of the splinted implants failed during the follow-ups. There were five failures in unsplinted partial cases. The average amounts of bone loss around the implants were 0.40 ± 0.35 mm, 0.56 ± 0.41 mm, and 0.59 ± 0.41 mm after 3, 6, and 12 months, respectively. Visible plaque was registered in 18% of the implants, and bleeding on probing was observed in 17% of the implants after 12 months. Conclusions High survival rates and favorable host tissue responses support the clinical performance of OPS implants. This study demonstrated that one-piece implants can be efficiently used by well-trained general dentists. [ABSTRACT FROM AUTHOR]

Background Titanium (Ti) implants have been used in the last four decades to replace missing teeth. Alternatives to Ti such as zirconia (Zr) may offer aesthetic advantages and be more acceptable to patients and clinicians concerned about Ti allergy but must show equivalent biological acceptability to Ti. Purpose The research aimed to investigate soft and hard tissue response to Ti and Zr implants in edentulous patients. Materials and Methods The research included 24 participants ( Ti = 12, Zr = 12) restored with one-piece ball-abutment implants to support overdentures. Participants received four maxillary implants (two in the premolar alveolus, one off center in the alveolar midline, and one wide-diameter implant in the anterior median palate) and three mandibular implants (one in the midline and bilateral posterior implants). Results Success rates for both Ti and Zr implants were low, 67.9% for all alveolar implants and a survival rate of 50.0% for the palatal implants. Only 11 (52.4%) of 21 palatal implants survived the follow-up period. Peri-implant health was equivalent for Ti and Zr implants and showed no statistically significant changes from loading to the 1-year follow-up. Statistically significant differences were noted in radiographic bone level between Ti and Zr implants ( p = .02), with Zr showing greater bone loss. Conclusions Although the failure rates with the one-piece Zr implants were higher than with the Ti ones, suggesting that the former's clinical usage as in this study cannot be recommended, it should be borne in mind that the fault may also lie with the novel prosthodontic design which was used. [ABSTRACT FROM AUTHOR]

Aim: To investigate whether the lack of keratinized mucosa (KM) affects peri‐implant health after 10 years of loading. Materials and Methods: Data from 74 patients with 148 implants from two randomized controlled studies comparing different implant systems were included and analyzed. Clinical parameters including bleeding on probing (BOP), probing depth (PD), plaque index, marginal bone loss (MBL), and KM width (KMW) at buccal sites were collected at baseline (time of the final prosthesis insertion), 5‐year and 10 years postloading. Multivariable logistic and linear regression models by means of a generalized estimated equation (GEE) were used to evaluate the influence of buccal KM on peri‐implant clinical parameters; BOP, MBL, PD, and adjusted for implant type (one‐piece or two‐piece) and compliance. Results: A total of 35 (24.8%) implants were healthy, 67 (47.5%) had mucositis and 39 (27.6%) were affected by peri‐implantitis. In absence of buccal KM (KM = 0 mm), 75% of the implants exhibited mucositis, while in the presence of KM (KMW >0 mm) 41.2% exhibited mucositis. Regarding peri‐implantitis, the corresponding percentages were 20% (KM = 0 mm) and 26.7% (KM >0 mm). Unadjusted logistic regression showed that the presence of buccal KM tended to reduce the odds of showing BOP at buccal sites (OR: 0.28 [95% CI, 0.07 to 1.09], p = 0.06). The adjusted logistic regression model revealed that having buccal KM (OR: 0.21 [95% CI, 0.05 to 0.85], p = 0.02) and using two‐piece implants (OR: 0.34 [95% CI, 0.15 to 0.75], p = 0.008) significantly reduced the odds of showing BOP. Adjusted linear regression by means of GEE showed that KM and two‐piece implants were associated with reduced MBL and MBL changes (p < 0.05). Conclusion: The lack of buccal KM appears to be linked with peri‐implant parameters such as BOP and MBL, but the association is weak. The design of one‐piece implants may account for their increased odds of exhibiting BOP. [ABSTRACT FROM AUTHOR]

Background: Interest in the use of one-stage surgery and immediate loading of oral implants has lately been increasing. Purpose: The aim of this study was to compare the 3-year results of one-stage surgery versus two-stage surgery, early loading versus loading after a 3-month healing period, and the use of one-piece implants versus the use of two-piece implants. Materials and Methods: The study included 108 patients with edentulous mandibles. Each patient was treated with four Brånemark System® implants (Nobel Biocare AB, Göteborg, Sweden) and with full fixed prostheses. Patients were consecutively treated and were distributed in four groups: group A (one-stage surgery), group B (control group with two-stage surgery), group C (one-piece implants), and group D (early loading). In groups A and B Brånemark Standard implants and standard abutments were used. In group C the conical one-piece Brånemark implant was used, and in group D the patients had Brånemark System Mk III implants together with multiunit abutments. All patients were observed for 3 years. Results: Of the 432 inserted implants, 24 were lost. Survival rates in the three experimental groups ranged from 93.2 to 93.3% whereas the survival rate in group B (the control group with two-stage surgery) was 97.5%. The differences between the groups were not statistically significant. The changes in marginal bone level were measured from fixture insertion to the final follow-up at 3 years. The bone loss in group D (early loading) was significantly less than in group B (the control group) whereas there were no differences in marginal bone change between the other groups. Conclusions: Early loading seemed to give good results in the anterior part of the mandible. The survival rate of the early-loaded implants did not significantly differ from that of implants inserted with the conventional two-stage procedure, but the mean marginal bone loss around the surviving implants was less with early loading. [ABSTRACT FROM AUTHOR]

Objectives: To analyze changes in radiographic bone density around short implants with and without cantilevers at 5 years post‐loading. Materials and Methods: Thirty‐six patients with two adjacent posterior missing teeth participated in this randomized controlled clinical trial. All patients were randomly allocated to receive either two short implants (6 mm) with single‐unit restorations (group TWO) or one single short implant (6 mm) with a cantilever restoration (group ONE‐C). Patients were followed up at 6 months, 1, 3, and 5 years. Radiographic analysis was performed, through an arbitrary gray scale value (GSV) of the peri‐implant bone, assessing the changes in radiographic density between groups and between time points. Differences in GSV between groups and over time were calculated using a generalized estimating equation to allow for adjustments for the correlation within individuals and between time points. Results: At 5 years, 26 patients remained in the study (15 in group ONE‐C; 11 in group TWO). Implant survival rates were 80.4% in group TWO and 84.2% in group ONE‐C (p = 0.894). The radiographic analysis revealed that GSVs increased in both groups over time (p < 0.001). The overall radiographic density was higher in group ONE‐C than in group TWO in the maxilla (p = 0.030). Conversely, in the mandible, these significant differences between the groups were not found (p > 0.05). Compared to the implants that survived, the implants that failed demonstrated a distinct radiographic density pattern (p < 0.05). Conclusion: Within the limitations of the present study, the radiographic bone density in the maxilla appears to increase distinctly around short implants when cantilevers are used. In contrast, the radiographic density in the mandible appears to be unaffected by the use of a cantilever, suggesting a lower threshold of adaptation to occlusal forces and thus a higher susceptibility to overload and implant loss at earlier time points. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to establish an objective criterion in terms of marginal bone level (MBL) to know the prognosis of an implant. Materials and Methods: A group of 176 patients in whom 590 implants were placed were included in this retrospective study. Patients older than 18 years, presenting either Kennedy class I or II edentulous section, or totally edentulous at least in one of the dental arches were included in this study. Those with any type of disturbance able to alter bone metabolism or with nontreated periodontal disease were excluded. Data on radiographic MBL at loading, 6 and 18 months later, age, gender, smoking habits, history of periodontitis, bone substratum, implant, and prosthetic features were recorded. Nonparametric receiver operating curves (ROC) were constructed for the MBL at 18 months in order to establish a distinction among high bone loser (HBL) and low bone loser (LBL) implants. Differences as a function of main variables were also determined, particularly abutment height and periodontal disease. Results: HBL implants lost at least 0.48 mm of MBL 6 months after loading; they reached at least 2 mm of MBL 18 months after loading. MBL rate followed a nonlinear trend, except in implants restored over long prosthetic abutments and in patients with history of severe periodontitis; in whom the rate of MBL over the time was nearly zero. Conclusion: Implants that lose more than 0.5 mm of marginal bone 6 months after loading are at great risk of not being radiographically successful anymore. Therefore, 0.5 mm of MBL is proposed as a distinctive and objective criterion of success in Implant Dentistry within a 6‐month follow‐up period. A prosthetic abutment height ≥2 mm resulted the most protective factor in the peri‐implant bone maintenance. [ABSTRACT FROM AUTHOR]

Background: Most implant treatment is performed with a two-stage surgical procedure. A disadvantage of these implant treatments is that they are time-consuming. Purpose: The aim of the present study was to evaluate the results of early loading in the edentulous mandible and to compare those results with treatment results of one-stage surgery followed by a healing period and with two-stage surgery. Material and Methods: The material comprises four treatment groups with a total of 108 patients with edentulous lower jaws and 432 implants. All patients were treated with Brånemark implants (Nobel Biocare AB, Gothenburg, Sweden) with a turned surface and fixed prostheses in the lower jaw, supported by four implants. The patients in group A were treated with a one-stage procedure, a two-piece implant, and a 3-month healing period before loading. Group B (control group) had a two-stage procedure, a two-piece implant, and a 3-month healing period. Group C had a one-stage procedure, a one-piece implant, and a 3-month healing period. Group D was treated with a one-stage surgical procedure, a two-piece implant, and early loading (within 3 weeks). All patients were provided with a Procera R Implant Bridge (Nobel Biocare) with a framework made by computer-assisted milling of one piece of pure titanium. All patients have been followed up for 1 year. Results: The survival rates were 93.2 to 93.3% in the experimental groups and 97.5% in the control group. The difference was not statistically significant. The measurements of the marginal bone level demonstrated a mean bone loss of 0.8 mm between fixture insertion and the 1-year examination in patients with early loading (group D) whereas the bone loss in patients who underwent a healing period before loading was 1.3 to 1.6 mm. The difference between the control group and the group with early loading was significant. Conclusions: Survival rates for patients treated with a one-stage procedure were lower than survival rates f... [ABSTRACT FROM AUTHOR]

Background: Narrow‐diameter implants (NDIs) have been proposed to address the dilemma of implant installation in cases of insufficient bone volume. However, the potential risk factors of failed NDIs, and whether reimplants with reliable efficacy are still controversial. Purpose: This study aimed to evaluate the survival/success rate of NDIs in the maxillary anterior region and that of reimplants at the same site, as well as to explore the potential risk factors of original and replaced implants. Materials and Methods: From January 2015 to April 2019, patients receiving NDIs in the anterior maxilla were enrolled in the present study. Multiple variables were assessed to exploit the risk factor of failed NDIs, including age, sex, implant sites, length, surface characteristics, and healing abutment designs. The relationship between bone augmentation and the number of missing teeth was assessed. For failed NDIs, the reasons for NDIs removal and marginal bone loss (MBL) were analyzed. The details and outcomes of reimplants were evaluated. Results: Cumulative survival rates (CSRs) and success rates of 1095 NDIs installed in 835 patients were 96.99% and 96.51%, respectively. In total, 33 of these NDIs failed. TiUnite (TU) surface was a risk factor and it affected the success rate (92.56%) and CSR (92.4%) of NDIs (P <.001). The single NDIs with bone augmentation have lower failure rate. The average MBL for 33 failed NDIs was 1.92 ± 1.91 mm. Additionally, 22 patients with 23 NDIs accepted reimplantation of previously failed NDIs, and the success rate of reimplants was 95.65%. Conclusions: Surface characteristic (TU surface) was a risk factor for failure of NDIs in the maxillary anterior region. Bone augmentation simultaneously performed during NDIs implantation was favorable for a single missing tooth. As an alternative plan, the reimplantation of failed NDIs was reliable and stable after successful bone reconstruction. [ABSTRACT FROM AUTHOR]

Background: Ongoing marginal bone loss is a threat to the longevity of implant‐supported prostheses. Aim: The aim of the present study was to retrospectively evaluate the survival rate and factors affecting marginal bone levels at a hydrophilic implant design after 5 years in function. Materials and Methods: The study group consisted of 51 consecutive patients previously treated with 159 hydrophilic implants (Neoss Straight Proactive implants) and scheduled for annual check‐ups with clinical and radiographic examinations during 5 years. Data were compiled for the entire study population as well as for two subgroups: one where guided bone regeneration (GBR) was performed (91 implants) and the other where no GBR procedures (68 implants) were performed. Marginal bone levels were measured from peri‐apical radiographs taken at placement and annual follow‐ups. Statistical analyses were applied to evaluate the effect of different factors on marginal bone remodeling. Results: Two implant failures, one from each subgroup, occurred during the first year of function resulting in an overall cumulative survival rate (CSR) of 98.7% after 5 years of loading. The mean marginal bone loss amounted to 0.7 ± 0.7 mm after 1 year and 0.8 ± 0.6 mm after 5 years. No implants showed more than 3 mm bone loss after 5 years. Age, gender, implant position, biotype, implant diameter, implant length, indication, surgical/loading protocol, and ISQ at prosthesis delivery were found to affect bone remodeling. No significant differences or correlations were seen for smoking, jaw, bone quantity, bone quality, GBR, sinus lift, and ISQ at implant placement. Conclusions: The present implant design performed well with few failures and minimal marginal bone loss after 5 years of loading. Marginal bone remodeling at implants is a complex phenomenon, which is affected by many patient‐, procedure‐, and implant‐related factors that need to be further investigated. [ABSTRACT FROM AUTHOR]

Background: The evolution of retention forces in one‐piece mini dental implants (MDIs) retaining implant overdentures (IODs) is of major importance, as the male parts cannot be exchanged, due to the implant design. Purpose: To report the evolution of retention forces of one‐piece MDIs, retaining mandibular IODs with ball/ O‐ring attachments during 5 years assessed in vivo. Materials and Methods: Four MDIs were installed in the interforaminal region and immediately loaded using the existing mandibular complete denture. Directly post‐op, at the 1‐year and the 5‐year follow‐up, the retention forces were assessed with a validated strain gauge at each implant site separately. Results: At the male part, changes could only be observed at implant site 34: During the first year, there was a statistically significant increase, whereas the retention forces were decreased at the 5‐year follow‐up. At the female part, retention forces decreased significantly over time. Baseline values could be reestablished by exchanging the O‐rings. The changes of the retention forces were more obvious in the posterior, compared to the anterior implants. Conclusions: Retention forces at the female part decrease significantly over time, when retaining mandibular IODs by MDIs with ball/ O‐ring attachments. Baseline values can be reestablished by exchanging the O‐rings. At the male part, changes of retention forces depend on the implant location. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: To investigate the effect of the apico‐coronal implant position on early and late crestal bone loss (CBL), in bone and tissue level implants. Materials and methods: Electronic and manual literature searches were conducted for controlled clinical trials reporting on CBL before and after functional loading of implants. Random effects meta‐analyses were applied to analyze the weighted mean difference (WMD) and meta‐regression was conducted to investigate any potential influences of select confounding factors. Results: Fourteen articles were included in the systematic review and 12 were included in the quantitative synthesis. For bone level implants, WMD comparing early CBL in equi and subcrestal placement was 0.15 mm (P = .18). For analyses of late CBL in bone level implants, equi and subcrestal placement revealed a 0.03 mm WMD (P = .88). Where in supra and subcrestal placement, WMD was 0.04 mm (P = .86). The comparison presented considerable heterogeneity between these two arms, where the P value for chi‐square test presented as .006. Finally, for CBL between supra and equicrestal placement, WMD was −0.64 mm (P < .0001), favoring the supracrestal group. For tissue level implants, WM of early and late CBL in implants placed equi‐crestally was 0.68 ± 0.12 mm and 0.69 ± 0.54 mm, respectively, where for implants placed sub‐crestally, the WM of CBL was 1.72 ± 0.15 mm and 2.26 ± 0.63 mm, respectively. Conclusion: Within the limitations of this study, it is recommended to place tissue level implants equicrestally, and bone level implants subcrestally. [ABSTRACT FROM AUTHOR]

Abstract: Background: Single piece implant in fixed prosthesis is widely been evaluated, however, long term evaluation of crestal bone loss and the wear of O‐ring in single piece ball attachment implant supported overdenture is yet to be evaluated Purpose: The present article evaluates the crestal bone loss around single piece ball attachment implants placed bilaterally in the canine region and the wear of O‐ring in implant supported overdenture over a period of three years. Materials and Methods: Twelve completely edentulous patients between the age group of 55‐65 years were selected. Two 3.3 mm × 13 mm myriad snap fit implants were placed in the mandibular interforaminal region. All the implants were conventionally loaded at three months after surgical placement. Intra‐oral periapical radiographs were made and crestal bone loss was measured at the end of one year and three years. The elasticity and wear of O‐Ring was assessed after three years of usage. Results: The crestal bone loss showed no significant difference between the first and third year after implant placement. The mean bone loss at the end of third year was 1.5 mm. Analysis of O‐ring for change in the elasticity showed reduction in displacement and a significant increase in maximum displacement and elongation. The area of O‐ring and yield stress did not show any changes from the standard value. Compression set damage was observed in the O‐ring at the end of three years. Conclusions: The present study shows that the bilateral single piece implant supported overdenture has a success rate equivalent to the two piece implant supported overdenture and is a viable treatment option. [ABSTRACT FROM AUTHOR]

Background Emerging evidence suggests that implant therapy may be a viable option for diabetic individuals with elevated glycemic levels. Purpose The purpose of this 2 year observational study was to evaluate survival and clinical complications of dental implants following placement in type 2 diabetes individuals having poor glycemic control. Materials and Methods Adult participants ( n = 24) with poorly controlled type 2 diabetes (8.0% ≤ HbA1c ≤ 12.0%) received two or more transgingival dental implants. Survival was evaluated after 1 (23 participants, 72 implants) and 2 (20 participants, 59 implants) years. Clinical complications were evaluated in 18 participants (52 implants) after 21-34 months. Relationships between complications and stratified HbA1c levels were assessed using Pearson's correlation test. Results Survival rates were 98.6% (71/72 implants) after 1 year and 96.6% (57/59 implants) after 2 years. Complications were identified in 29% of participants with peri-implant mucositis, the most common event. Complications correlated directly with number of implants across HbA1c strata (0.42, R2 = 0.66). There was no correlation between HbA1c and the occurrences of complications or mucositis. Conclusions This 2-year evaluation supports the broader application of implant therapy in type 2 diabetes individuals with poor glycemic control in demonstrating high survival rates with limited complications. [ABSTRACT FROM AUTHOR]

Background Peri-implant bone levels can vary according to the implant neck macro-design and the implant-abutment interface. Purpose To compare the changes in soft and hard tissues when using a one-piece implant with a machined collar (TG) versus a two-piece implant with a progressive platform widening and a platform switching connection (SP). Material and methods Partially edentulous patients willing to receive one or two implants in the posterior maxilla or mandible were randomized to the control (TG) or to the test group (SP). Final prostheses were delivered after 12 months. Radiographic measurements of interproximal bone levels (primary outcome) were assessed at implant loading and 1-year postloading. Clinical, patient related outcomes and adverse events were assessed at loading and after 6 and 12 months. Results Sixty-one implants were placed in 47 patients, 37 patients (18 in the TG group and 19 in the SP group), and 47 implants (23 TG and 24 SP) completed the 24-months follow up. At the patient level, a significantly greater bone resorption from baseline to implant loading was observed in the SP group (−0.42 ± 0.45 vs −0.07 ± 0.45; P = .001*), while from loading to the final visit, the TG group had significantly greater bone loss than the SP group (−0.26 ± 0.22 vs −0.11 ± 0.2; P = .020*). At 24 months after surgery, there were no significant differences between both groups (control: 0.33 ± 0.49 vs test: 0.53 ± 0.53; P = .230). Similarly, no significant differences were observed for the secondary outcomes. Conclusions Both types of implant reported high survival rates and similar bone level changes, clinical parameters, and patient related outcomes after 12 months of loading. [ABSTRACT FROM AUTHOR]

Background The use of narrow-diameter implants ( NDIs; <3.75 mm) constitutes an alternative to bone augmentation procedure. Long-term evaluation of NDIs with a diameter <3.0 mm is still lacking. Purpose Analyze the long-term outcomes of 2.5-mm NDIs splinted to regular-sized implants for supporting partial and complete fixed prostheses. Materials and Methods Patients charts were retrospectively analyzed to select patients treated by the insertion of at least one 2.5-mm two-piece implant before July 2005. The study was based on the available charts (no patient was recalled). Patient's demographic data were described. The known implant length was used as a reference to calibrate the linear measurements of marginal bone loss on digital periapical radiograph. Implant details, survival and prosthetic complications were analyzed. Results Thirty-seven 2.5-mm implants placed in 20 patients (mean age at surgery: 54.05 ± 9.7 years) in maxilla and mandible were included and evaluated. The implants' mean follow-up time since insertion was 6.5 ± 3.2 years (range 0 to 9.7 years). The follow-up time was more than 7 years for 22 implants. One implant failed due to lack of osseointegration. Two prosthetic complications (connector and porcelain fracture) occurred. The survival rate was 97.3% for implants and 92.0% for prostheses. The mean marginal bone loss at the mesial and distal aspect was 0.70 ± 0.55 and 0.72 ± 0.56 mm, respectively. Conclusions When dental implants of 2.5 mm in diameter are splinted by a fixed prosthesis, long-term favorable outcomes could be obtained. [ABSTRACT FROM AUTHOR]

Background Current strategies to reduce medical device-associated infections propose zirconia as a potential implant material which may limit bacterial adhesion. Because multinucleated giant cells ( MNGCs) have been detected on these implant surfaces, concerns have been raised regarding tissue integration. Purpose The present study examined the presence of MNGCs and their subsequent effect upon tissue integration. Surface-modified implants made of yttria-stabilized ( TZP) and alumina-toughened zirconia ( ATZ) were compared with commercially pure titanium ( Ti). Materials and Methods Seven miniature pigs received three implants on either side of the maxilla. After healing periods of 4 and 8 weeks, the tissue response at the implant surfaces was characterized according to three specific parameters: bone-to-implant contact ( BIC), MNGC-to-implant contact ( MIC), and the peri-implant bone density ( BD). Results Despite being present on all tested implant surfaces, MNGCs were not associated with an inflammatory cell infiltrate or with fibrous encapsulation. MNGCs were less numerous on the Ti implants (range: 3.9-5.2%) compared with the ceramic implants (range: 17.6-30.3%, p < .0001). Even though the values of newly formed bone and pristine bone in direct contact with the implant surfaces were high at 4 weeks ( tBIC: Ti = 82.3%, TZP = 64.3%, ATZ = 70%), a negative correlation was observed between the presence of MNGCs and newly formed bone at the implant surface ( p < .001). Interestingly, the newly formed peri-implant bone density, defined as the percentage of new bone area inside the screw threads ( nBD), was not diminished by the presence of MNGCs. Conclusions Differences in the presence of MNGCs and the BIC parameters between Ti and the ceramic implants appear to be a local cellular phenomenon which is restricted to the implant-bone marrow interface and do not affect the peri-implant bone formation. Factors triggering MNGC differentiation and their persistence in response to biomaterial surface need to be investigated in future studies. [ABSTRACT FROM AUTHOR]

Background and Purpose Osteoporosis is a major skeletal disease affecting millions of people worldwide. Recent studies claim that patients with osteoporosis do not have a higher risk of early implant failure compared to non-osteoporotic patients. The aim of this study was to assess the effect of skeletal osteoporosis and local bone density on initial dental implant stability. Materials and Methods Seventy-three patients were recruited and were assigned (based on a Dual-energy X-ray Absorptiometry scan) to either the osteoporosis (Opr), osteopenia (Opn), or control (C) group. Forty nine of the 73 patients received dental implants and had implant stability measured by means of resonance frequency analysis (RFA) at implant placement and at prosthetic abutment placement. On the computerized tomography scans, the cortical thickness and the bone density (Hounsfield Units) at the sites of implant placement were measured. Results At implant placement, primary stability was on average lower in group Opr (63.3 ± 10.3 ISQ) than in group Opn (65.3 ± 7.5 implant stability qutient (ISQ)), and group C (66.7 ± 8.7 ISQ). At abutment placement, a similar trend was observed: group Opr (66.4 ± 9.5 ISQ) scored lower than group Opn (70.7 ± 7.8 ISQ), while the highest average was for group C (72.2 ± 7.2 ISQ). The difference between groups Opr and C was significant. Implant length and diameter did not have a significant effect on implant stability as measured with RFA. A significant correlation was found between local bone density and implant stability for all regions of interest. Conclusions Implant stability seems to be influenced by both local and skeletal bone densities. The lower stability scores in patient with skeletal osteoporosis reinforce the recommendations that safe protocols and longer healing times could be recommended when treating those patients with dental implants. [ABSTRACT FROM AUTHOR]

Background The aim of this clinical study was to compare clinical evaluations of implants in the aesthetic zone with smooth collars of different length. Materials and Methods Sixty-six patients requiring extractions of one, two, or three teeth in the aesthetic zone of the maxilla were enrolled in this study. Ninety-four implants were positioned and were loaded immediately after tooth extraction. Forty-seven implants with a short smooth collar of 0.5 mm ( SCI) and 47 implants with a long smooth collar of 1.8 mm ( LCI) were utilized in this study and were placed using a nonsubmerged approach. Clinical (gingival index, modified plaque index, modified bleeding index, probing depth, gingival recession) and intraoral digital radiographic parameters were measured at baseline and after 6, 12, 24, and 36 months of healing to evaluate crestal bone loss levels over time. Results After a follow-up period of 36 months, a survival rate of 100% was reported. The SCI group showed a mean bone loss of 1.07 ± 0.38 mm at 12 months and 1.09 ± 0.38 mm at 36 months. The LCI group showed a mean bone loss of 0.46 ± 0.14 mm at 12 months and 0.53 ± 0.12 mm at 36 months. After the 36-month follow-up period, both groups showed stable bone levels over time. Statistically significant differences were found between groups ( p < .05). No statistically significant differences were found between SCI and LCI groups with regard to clinical parameters over time. Conclusions This study revealed significant differences in radiographically observed marginal bone loss between the two types of implant with different smooth-collar lengths, but no differences in gingival vestibular margin outcome were observed. [ABSTRACT FROM AUTHOR]

Background Long-term data regarding survival and crestal bone loss for Replace Select Tapered implants (Nobel Biocare AB, Gothenburg, Sweden) are lacking. Purpose The study aims to present the 5-year outcomes from a retrospective analysis of Replace Select Tapered implants placed and restored in consecutive patients. Materials and Methods A total of 88 consecutive patients (32 male, 56 female, mean age 65 ± 12 years) treated by one clinician ( PP) were clinically and radiographically evaluated during at least 5 years of function. A total of 271 dental implants ( Replace Select Tapered, Nobel Biocare AB) with an oxidized surface ( Ti Unite, Nobel Biocare AB) had been placed in both jaws (228 in the maxilla, 43 in the mandible). The majority of implants were placed in healed sites ( n = 244), while 27 implants were immediately placed in extraction sockets. The majority of implants ( n = 262) healed for 3 to 4 months prior to loading, and nine implants were immediately loaded. A total of 121 implant-supported restorations were delivered; 42 single tooth replacements, 61 fixed partial bridges, 14 fixed full bridges, and 4 fixed partial implant-tooth connected bridges. The marginal bone level was measured in intraoral radiographs taken after surgery (baseline), and after 1, 2, 3, 4, and 5 years. Results Fifty-one patients with 160 implants were followed throughout the study. One implant failed at healing abutment connection 4 months after insertion, resulting in a cumulative survival rate of 99.6%. The average crestal bone loss was 0.9 ± 1.6 mm after 1 year and 0.1 mm ± 2.4 after 5 years. There were 14.8% of measured implants that showed more than 2 mm and 5.2% more than 3 mm bone loss after 5 years, with no progression since the 1-year examination. One patient (2.0%) treated with six implants presented with significant crestal bone loss and recurrent peri-implant purulent infections at all implants. Conclusion The present retrospective 5-year study showed high survival rate and steady crestal bone levels for Replace Select Tapered dental implants. [ABSTRACT FROM AUTHOR]

Objectives A 3-year proof-of-principle study was initiated to evaluate the clinical efficacy of immediately loading titanium dental implants with surfaces enhanced with porous tantalum trabecular metal ( PTTM). First-year interim results are presented. Materials and Methods Healthy, partially edentulous patients ( n = 30) were enrolled and treated per protocol (minimum insertion torque: ≥35 Ncm) with 37 implants placed in one or two premolar or molar locations in either jaw (study group). Implants were immediately provisionalized out of occlusion with single acrylic crowns. After 7 to 14 days of soft tissue healing, implants were definitively restored in occlusion with ceramometal crowns. Because most study group implants (54.1%, n = 20) had less than 1 year of clinical follow-up, this interim analysis was limited to the first 22 consecutively placed implants in 17 subjects (10 women and 7 men) who completed 1 year of clinical follow-up to date (focus group). Results To date, one implant failed to integrate in the study group (survival = 97.3%, n = 36/37). Focus group implants achieved 100% ( n = 22/22) survival with 0.43 ± 0.41 mm of mean marginal bone loss. There were no serious complications. Conclusion Early clinical findings indicated that immediate loading of PTTM implants was safe and effective under the controlled study conditions. [ABSTRACT FROM AUTHOR]

Purpose The study aims to assess the total soft tissue (ST) width, crestal bone level (CBL), bone-to-implant contact (BIC), and bone density (BD) for zirconia implants textured with microgrooved surfaces and immediately loaded. Materials and Methods This study included 51 implants; one implant from each study group was retained for surface characterization. The 48 remaining implants were inserted randomly in premolar areas of both sides of the healed edentulous lower jaws of foxhound dogs. They were divided into three groups of 16: control (titanium); test A (zirconia), and test B (microgrooved zirconia). The implants were splinted and covered with an acrylic bridge. A split-mouth design was used and immediate occlusal loading was applied on one side, while the other side did not have occlusal contact. ST, CBL, BIC, and BD were evaluated after 3 months. The effects of immediate loading on these parameters were analyzed. Results All the implants were osseointegrated. ST was established at 3 months with mean values of 2.9 ± 0.4 mm for all groups. No differences were appreciated between loaded and unloaded sides regarding ST ( p > .05). CBL showed a mean of 1.2 ± 0.3 mm for all groups without differences between loaded and unloaded sides ( p > .05). BIC percentages were significantly higher for loaded all-microgrooved implants ( p < .05). BD percentages were higher in areas close to all-microgrooved implants ( p < .05) and significantly higher for loaded implants than unloaded. Conclusions Within the limitations of the present study, it may be concluded that for zirconia dental implants with microgrooved surfaces and immediate loading, the thickness of STs remains stable resulting in 3 mm mean biologic width, that crestal bone preservation is related to insertion depth, and that higher BIC percentages and increased BD around implants microgrooved over the entire intraosseous area may be expected at 3 months following implant insertion and immediate loading. [ABSTRACT FROM AUTHOR]

Background Dental literature has limited number of publications regarding long-term outcome data of immediate restoration of single missing teeth with an implant-supported provisional crown. Purpose This 5-year study evaluated hard and soft tissue responses to the immediate placement of single implant-supported provisional crowns. Materials and Methods Twenty patients received one dental implant restored immediately with a provisional acrylic resin screw-retained crown. Crestal bone loss was evaluated from standardized periapical radiographs collected at 3-month intervals for the first 21 months followed by a 5-year evaluation. Historical controls acquired from available dental literature were used for comparison. Results One implant failed within 2 months of surgical placement, presenting with pain and mobility. The remaining implants demonstrated no infection, pain, or radiolucencies. Nineteen implants were clinically immobile, osseointegrated, and asymptomatic at 21 months. At 5 years, one patient died, three patients were noncompliant, and 15 implants were evaluated as functional. Mean bone loss ( MBL) at 1 year and 21 months was approximately 0.5 ± 0.5 mm and 0.70 ± 0.26 mm at 5 years. There was no statistically significant difference between MBLs at p < 0.05. Conclusions Immediate provisionalization of single dental implants compares favorably with conventional loading protocols. Long-term data suggest that immediate provisionalization of single dental implants is a viable treatment option. [ABSTRACT FROM AUTHOR]

Aim To elucidate the influence of initial soft tissue thickness on peri-implant bone remodeling. The research hypothesis was that implants installed in patients or at sites with thin mucosal tissues would show increased peri-implant bone loss. Material and Methods 79 edentulous patients were consecutively treated with two non-splinted implants supporting an overdenture in the mandible. During recall-visits, peri-implant health was determined by means of probing pocket depth and the modified plaque/bleeding index. Digital peri-apical radiographs were taken from individual implants. Bone level changes were measured from a reference point (lower border of the smooth implant collar) to the marginal bone-to-implant contact level. The linear mixed-effect model analysis was adopted to analyze the influence of clinical parameters and transmucosal abutment height on peri-implant bone loss. Results 67 patients attended the 1-year and 66 the 2-year recall-visit. Mean bone level changes were 0.89 mm ( SD 0.62) and 0.90 mm ( SD 0.66), plaque scores 0.82 ( SD 0.94) and 0.87 ( SD 0.92), bleeding scores 0.46 ( SD 0.68) and 0.56 ( SD 0.72) and PPD 1.65 mm ( SD 0.60) and 1.78 mm ( SD 0.59) after 1 year and 2 years respectively. The linear mixed-effect model revealed increasing bone level changes with decreasing abutment heights. Peri-implant bone level changes were significantly higher for implants with abutments of <2 mm (1.17 mm, p < .01; 1.23 mm, p < .01), 2 mm (0.86 mm, p < .01; 1.03 mm, p < .01) or 3 mm (0.38 mm, p = .046; 0.41 mm, p = .044) compared to ≥4 mm-abutments (bone level changes set to zero as reference value) both after 1 year and 2 years and bone level changes were significantly influenced by probing pocket depth ( p < .01, p < .01), but not by plaque ( p = .31, p = .09) and bleeding scores ( p = .30, p = .40). Conclusion The present study suggests that implants with lower abutments, reflecting the initial gingival thickness, lose more peri-implant bone, possibly by a re-establishment of the biological width. [ABSTRACT FROM AUTHOR]

Aim: To assess the effect of platform switching on peri-implant bone remodeling around short implants (8.5 mm) placed in the resorbed posterior mandibular and maxillary region of partially edentulous patients. Materials and Methods: Seventeen patients with one or more missing teeth at both sides in the posterior region were, according to a split-mouth design, randomly assigned to be treated with a platform-matched (control) implant on the one side and a platform-switched implant (test) on the other side. A total of 62 short implants (8.5 mm) with a dual-acid etched surface with nanometer-sized calcium phosphate particles was placed. Follow-up visits were conducted one month and one year after placing the implant crown. Outcome measures were interproximal bone level changes, implant survival and clinical parameters. Results: One year after loading, peri-implant bone remodeling around test implants (0.53 ± 0.54 mm) was significant less than around control implants (0.85 ± 0.65 mm; p = .003). With regard to implant survival and clinical parameters no significant differences were observed between test and control implants. Conclusions: This study suggested that peri-implant bone remodeling is affected by platform switching. One year after loading, interproximal bone levels were better maintained at implants restored according to the platform switching concept. [ABSTRACT FROM AUTHOR]

Purpose: The present article aims to analyze the available clinical data on the survival and success rate of dental zirconia implants (ZI). Material and Method: Studies (2006-2011) listed in the bibliography were obtained by using the key words 'zirconia, zirconium, implants, dental, clinical' and combinations of these in different databases and on the internet. These articles served as a basis for the article. Results: A total of 17 clinical studies were found, involving 1,675 implants and 1,274 patients. In 16 studies, one-piece implant systems were investigated. The survival rates for ZI range from 74-98% after 12-56 months, with success rates between 79.6-91.6% 6-12 months after prosthetic restoration. However, the design of most of the studies show considerable shortcomings, and only low evidence level. Conclusion: The small number of studies and the limited period of observation permit only a qualified statement on the clinical success of ZI. The results available to date indicate that ZI are inferior to titanium implants (TI) with regard to survival and success rates. Well-conducted long-term studies are urgently needed to permit a meaningful assessment of the survival or success rates of ZI and a statement concerning their application as an alternative to TI. [ABSTRACT FROM AUTHOR]

ABSTRACT Aim: The aim of this study was to assess the performance of conventional rotative instruments and a piezoelectric device for maxillary sinus floor elevation surgery, and to assess whether application of a resorbable membrane reduces resorption of an augmented site in a randomized clinical trial. Materials and Methods: Thirty-six consecutive patients (59.2 ± 10.7 years, range 38-76 years) needing bilateral sinus floor elevation surgery agreed to participate in this study. In a parallel split mouth design randomized clinical trial, in which the allocation of the surgical technique to be used on the determined sites was randomly assigned, one site was always treated with conventional rotative instruments (control group) and the other site with piezosurgery (test group). In addition, in a random order, the grafted sites were covered with a collagen membrane or no membrane. After a healing period of 3-4 months implants were placed. Results: Comparison of clinical features of the test and control sites revealed no differences with regard to wound healing and complications (perforations of the sinus membrane) during or postsurgery ( p = .458, p = 1.0, respectively). A clinically insignificant, but statistically shorter operation time was observed when using conventional rotative instruments (11.1 ± 2.4 minutes) than using piezosurgery (15.1 ± 2.9 minutes; p < .001). In both groups, application of a resorbable membrane did not result in less horizontal bone resorption (membrane: 1.43 mm, no membrane: 1.06 mm; p = .062); All 193 implants could be placed with primary stability. One year after functional loading, survival rate was 100%. Conclusion: It can be concluded that, for maxillary sinus floor elevation surgery, a piezoelectric device shows no advantages over rotative instruments as well as that placement of a barrier membrane did not reduce resorption of the augmented site. [ABSTRACT FROM AUTHOR]

ABSTRACT Background: Concerns have been raised that use of surface-modified implants may result in peri-implant infection and marked marginal bone loss over time. Purpose: The aim of this prospective study was to evaluate the survival rate, marginal bone, and soft tissue conditions at surface-modified titanium dental implants after 10 years of function. Material and Methods: Forty-six totally and partially edentulous patients were provided with 121 Brånemark oxidized implants (TiUnite™, Nobel Biocare AB, Gothenburg, Sweden). Twenty-four (20%) implants were immediate loaded and 97 (80%) were placed using a two-stage procedure. A total of 22 single, 23 partial, and 7 total restorations were delivered. Clinical and radiographic checkups were carried out after 3, 6, 12 months, and thereafter annually up to 10 years. At these occasions, oral hygiene was evaluated and peri-implant mucosa examined by probing. If needed, patients were enrolled in an individual program for hygiene controls and professional cleaning. Marginal bone loss was evaluated in intraoral radiographs taken at baseline and after 1, 5, and 10 years of function. Results: One (0.8%) implant failed after 8 years giving a Survival Rate (SR) of 99.2% after 10 years. A total of 11 sites (9.2%) showed bleeding on probing (BP) at the 10th annual checkup. The mean marginal bone loss was 0.7 ± 1.35 mm based on 106 readable pairs of radiographs from baseline and from the 10th annual examination. Twelve (11.3%) implants showed more than 2 mm bone loss, and five (4.7%) showed more than 3 mm of bone loss after 10 years. For the latter, all patients were smokers and had poor or acceptable oral hygiene. All five implants with >3 mm bone loss showed BP and two (1.9%) showed suppuration from the pocket. For the remaining seven implants with more than 2 mm bone loss, no correlation to smoking, oral hygiene, bleeding, or pus could be seen. Time/marginal bone level plots of the 12 implants with more than 2 mm bone loss after 10 years, showed minor changes from the first annual checkup except for the two infected implants. Conclusions: It is concluded that good long-term clinical outcomes can be obtained with oxidized titanium dental implants. Only 1.9% of examined implants showed significant marginal bone loss together with bleeding and suppuration after 10 years of function. [ABSTRACT FROM AUTHOR]

Background The reasons for long-term marginal bone loss around oral implants are not well understood. Purpose The aim of this paper is to analyze presented evidence behind anticipated reasons for long-term marginal bone loss around oral implants. Materials and Methods A computerized research was conducted on Pub Med in April 2011 with the following keywords: oral implants and marginal bone resorption/crestal bone loss/bone loss/bone resorption. This search resulted in a total of one thousand one hundred ninety-four papers of which seven hundred fifty-three were clinical contributions. Further search and filtering finally resulted in 21 experimental studies and one hundred sixteen clinical studies, which were reviewed. Results No evidence was found that primary infection caused marginal bone resorption. Clinical papers that have reported high levels of peri-implantitis were not supported by data given. Clinical evidence was presented that the so-called combined factors (implant hardware, clinical handling, and patient characteristics) may lead to marginal bone resorption. However, once tissue damage has been caused by combined factors, inflammation and/or infection may develop secondarily and then result in peri-implantitis that may need particular clinical treatment. Conclusions As marginal bone loss primarily depends on numerous background factors, it seems logical that, for example, the use of poorly constructed implants placed and handled by untrained clinicians may result in high numbers of patients with secondary problems in form of peri-implantitis; having said this, control of combined factors may likewise lead to very good clinical results where peri-implantitis would represent a very rare disease indeed even at follow-up times of 10 years or more. [ABSTRACT FROM AUTHOR]

ABSTRACT Background: Implant survival and success have shown to be related to a number of factors. Aim: To evaluate the impact of implant design on implant survival and success, focusing on thread pitch and implant shape. Materials and Methods: Non-smoking patients treated by two experienced periodontists with standard diameter externally-hexed Southern® implant(s) inserted in healed bone were retrospectively selected. A one-stage surgical approach was used in all cases and implants had been installed for at least 6 months. Information pertaining to patient-related variables, time of loading, implant design and radiographical outcome was retrieved from patients' records. Implant success was defined according to the criteria by Albrektsson and Isidor, taking into consideration bone level, defined as the distance from the implant-abutment interface to the first bone-to-implant contact. Results: In total, 59 patients treated with one hundred eleven externally-hexed Southern Implants® met the inclusion criteria. Fifty-six straight implants with a thread pitch of 0.6 mm and 55 tapered implants with a thread pitch of 1.0 mm were placed. The total implant survival rate was 98.2% after a mean follow-up period of 14 months (range 6-28). The mean bone level was 1.35 mm (SD 0.46, range 0.59-3.70) and the overall implant success rate was 75.7%. Age, gender, length, and time of loading were not decisive for implant neither failure nor bone loss in contradiction to implant design and thread pitch ( p < .01). Tapered implants with a 1.0 mm thread pitch were less successful than parallel-walled implants with a 0.6 mm thread pitch. Conclusion: The Southern Implants® system shows good short-term survival rates and bone preservation. However, bone remodeling seems affected by the implant design. Whether this is due to the tapered shape of the implant or the thread pitch is unclear and needs to be elucidated in future research. [ABSTRACT FROM AUTHOR]

ABSTRACT Purpose: A recent in vivo study has shown considerable contamination of internal implant and suprastructure components with great biodiversity, indicating bacterial leakage along the implant-abutment interface, abutment-prosthesis interface, and restorative margins. The goal of the present study was to compare microbiologically the peri-implant sulcus to these internal components on implants with no clinical signs of peri-implantitis and in function for many years. Checkerboard DNA-DNA hybridization was used to identify and quantify 40 species. Material and Methods: Fifty-eight turned titanium Brånemark implants in eight systemically healthy patients (seven women, one man) under regular supportive care were examined. All implants had been placed in the maxilla and loaded with a screw-retained full-arch bridge for an average of 9.6 years. Gingival fluid samples were collected from the deepest sulcus per implant for microbiological analysis. As all fixed restorations were removed, the cotton pellet enclosed in the intra-coronal compartment and the abutment screw were retrieved and microbiologically evaluated. Results: The pellet enclosed in the suprastructure was very similar to the peri-implant sulcus in terms of bacterial detection frequencies and levels for practically all the species included in the panel. Yet, there was virtually no microbial link between these compartments. When comparing the abutment screw to the peri-implant sulcus, the majority of the species were less frequently found, and in lower numbers at the former. However, a relevant link in counts for a lot of bacteria was described between these compartments. Even though all implants in the present study showed no clinical signs of peri-implantitis, the high prevalence of numerous species associated with pathology was striking. Conclusions: Intra-coronal compartments of screw-retained fixed restorations were heavily contaminated. The restorative margin may have been the principal pathway for bacterial leakage. Contamination of abutment screws most likely occurred from the peri-implant sulcus via the implant-abutment interface and abutment-prosthesis interface. [ABSTRACT FROM AUTHOR]

ABSTRACT Background: Flapless, free-handed implant surgery offers advantages for patient comfort, but studies on long-term clinical success based on marginal bone loss are scarce. Aim: The aim of this study was to compare single implants installed with a flap (F) or flapless (FL) surgery with respect to survival and marginal bone preservation after at least 3 years. Materials and Methods: Fifty-three TiUnite™ Brånemark implants, installed in 49 patients (27 females; 22 males; mean age 53 years) were examined. Then, 25 F and 28 FL were delayed loaded; bone level from the abutment-implant level was measured on intraoral radiographs. From 44 (21 F, 23 FL), 31 (18F, 13FL), and 36 (18 F, 18 FL) implants, radiographs were available at baseline and after 1 and 3 years of function. Results: The overall survival rate was 100% and the overall mean bone loss after an average of 38 months was 1.35 mm (SD 0.91; range 0-3.7). Both F and FL showed increasing bone loss during the first year with a higher bone loss for FL than for F sites ( p < .01). Afterward, no further bone loss occurred and both groups were statistically equal ( p > .7). On individual implant level, nearly 80% in both F and FL were considered a success showing bone loss between 1.5 and 1.9 mm. Conclusions: Single implants yield an excellent prognosis with stable bone levels irrespective of the surgical technique, and free-handed flapless surgery is a viable alternative to more extensively planned guided surgery. Proper case selection and clinical experience are considered prerequisites for a predictable treatment outcome. [ABSTRACT FROM AUTHOR]

Purpose: With the increasing popularity and publication of loading implants at the time of placement, including at time of dental extraction and simultaneous with reconstructive procedures, the objective was to evaluate known variables identified for a traditional unloaded healing period and determine the applicability of these variables to immediate loading. Materials: A total of 124 published reports available as of January 2008 that contained information about loading from the time of surgery up to 3 months postsurgically were examined in light of published variables affecting osseointegration based on a 2 stage surgical approach. Methods: The articles were examined to differentiate between immediate loading (within the initial 48 hours) and early/delayed loading of implants. Success or survival criteria were noted, and where reasons for failure were available, categorized according to six variables considered as determinants for maintaining a long-term bone-to-implant contact. Results: Approximately 60 of the 124 reports described immediately loading implants within 48 with single-tooth, partial, and full-arch restorations, as well as implant overdentures. The implant success or survival rates ranged from 70.8% to 100%. Most studies considered implant survival to be the only criterion for success. Conclusions: Of six parameters identified in 1981 as influencing osseointegration, two parameters (the status of the bone/implant site and implant loading conditions) appear to have diagnostic implications, whereas three (implant design, surgical technique, and implant finish) may affect immediate loading positively or adversely. [ABSTRACT FROM AUTHOR]

Introduction: The Nobel Direct® implant (Nobel Biocare AB, Göteborg, Sweden) was developed to minimize marginal bone resorption and to result in “soft tissue integration” for an optimized aesthetic outcome. However, conflicting results have been presented in the literature. The aim of this present study was to evaluate the clinical and microbiologic outcomes of Nobel Direct implants. Materials and Methods: Ten partially edentulous subjects without evidence of active periodontitis (mean age 55 years) received 12 Nobel Direct implants. Implants were loaded with single crowns after a healing period of 3 to 6 months. Treatment outcomes were assessed at month 24. Routine clinical assessments, intraoral radiographs, and microbiologic samplings were made. Histologic analysis of one failing implant and chemical spectroscopy around three unused implants was performed. Paired Wilcoxon signed-rank test was used for the evaluation of bone loss; otherwise, descriptive analysis was performed. Results: Implants were functionally loaded after 3 to 6 months. At 2 years, the mean bone loss of remaining implants was 2.0 mm (SD ± 1.1 mm; range: 0.0–3.4 mm). Three out of 12 implants with an early mean bone loss >3 mm were lost. The surviving implants showed increasing bone loss between 6 and 24 months ( p = .028). Only 3 out of the 12 implants were considered successful and showed bone loss of <1.7 mm after 2 years. High rates of pathogens, including Aggregatibacter actinomycetemcomitans, Fusobacterium spp., Porphyromonas gingivalis, Pseudomonas aeruginosa, and Tanerella forsythia, were found. Chemical spectroscopy revealed, despite the normal signals from Ti, O, and C, also peaks of P, F, S, N, and Ca. A normal histologic image of osseointegration was observed in the apical part of the retrieved implant. Conclusion: Radiographic evidence and 25% implant failures are indications of a low success rate. High counts and prevalence of significant pathogens were found at surviving implants. Although extensive bone loss had occurred in the coronal part, the apical portion of the implant showed some bone to implant integration. [ABSTRACT FROM AUTHOR]

Background: The use of immediate/early implant loading protocols offers obvious advantages for the patient. Although well documented in the totally edentulous mandible, information about clinical outcomes from such protocols in the partially edentate maxilla is lacking. Purpose: The present study was conducted to clinically and radiographically evaluate a tapered implant design with an oxidized surface for immediate/early loading in the partially edentulous maxilla. The aim was also to correlate implant stability measurements using resonance frequency analysis (RFA) with implant diameter and length, bone quality and quantity, and marginal bone levels and marginal bone loss. Materials and Methods: A total of 32 patients with a need of implant treatment in their partially edentulous maxilla were included in the study. A total of 53 Replace Select TiUnite™ implants (Nobel Biocare AB, Göteborg, Sweden) were used in the study; 16 for single tooth replacements in 16 patients and 37 implants for partial bridges in another 16 patients. The single tooth replacements were loaded the same day with a temporary crown, while permanent partial bridges were delivered within 16 days. Intraoral radiographs were taken at surgery and after 1 year for marginal bone measurements. RFA measurements were performed at baseline and after 3, 6, and 12 months. Results: One implant used for a single tooth replacement failed, giving an overall survival rate of 98.1% after 1 year. On average, 1.1 mm (SD 1.0) bone was lost during 1 year; 1.5 mm (SD 1.0) in single tooth and 0.9 mm (SD 1.0) in partial cases. The implant stability increased with time from 63.3 implant stability quotient (ISQ) (SD 6.1) at baseline to 64.3 (SD 5.3), 65.0 (SD 4.6), and 66.8 (SD 5.6) after 3, 6, and 12 months, respectively. The average change from baseline to 1 year was 3.3 ISQ (SD 5.0) and was statistically significant ( p < .05). There was no difference between single and partial cases. Implant stability correlated with bone quantity and quality at implant sites, but not with marginal bone level measurements. Conclusions: It is concluded that immediate/early loading can be used in the partially edentulous maxilla with good clinical and radiographic short-term outcomes. Implant stability at placement correlated with bone quantity and quality, and increased with time as measured with RFA, indicating a favorable bone tissue response to the loaded implants. Any correlations between RFA and marginal bone level measurements were not observed in the present study. [ABSTRACT FROM AUTHOR]

Background: Early loading of implant-supported prostheses in the edentulous mandible is widely accepted, but do the clinical results replicate those of delayed loading? Purpose: The aim of this study was to evaluate clinical outcome and patient satisfaction with early or delayed loading in patients treated with fixed prostheses, using three different implant systems. Materials and Methods: One hundred and nine consecutively treated patients received 490 implants supporting fixed prostheses; 82 patients with Brånemark System® implants (Nobel Biocare AB, Göteborg, Sweden), 16 with Astra Tech® implants (Astra Tech AB Dental Implant system, Mölndal, Sweden), and 11 with ITI® MonoType® implants (ITI Dental Implant System®, Institute Straumann AG, Waldenburg, Switzerland). Prostheses were placed within 2 to 3 weeks in 55 patients; 54 patients underwent a two-stage procedure. Data were collected from patient records and radiographs; 83 patients attended a clinical examination and received a questionnaire. Results: All patients had fixed prostheses at follow-up with a mean observation time of 3.5 years. Cumulative survival rates (CSRs) were 92.5% of prostheses and 94.4% of implants for early loading, and 98.0 and 97.9% for delayed loading. The mean radiographic bone loss after the first year was small, and at 5 years less than 0.2 mm for both groups. With early loading, significantly more prostheses ( p < .05) needed adjustment or replacement. Conclusion: Statistically significantly more prostheses needed adjustment or replacement in the early group. The present study suggested lower CSRs for prostheses and implants in the early loading group after 5 years; the difference was not statistically significant. Larger study samples are needed to verify statistically small differences between treatment techniques. [ABSTRACT FROM AUTHOR]

Background: Zirconia (ZrO2) might be an alternative material to titanium (Ti) for dental implant fabrication. However, no data are available on the fracture strength of one-piece ZrO2 oral implants. Purpose: The objective of this study was to evaluate the fracture strength of ZrO2 implants after exposure to the artificial mouth. Materials and Methods: One hundred twenty ZrO2 and Ti implants were used. The Ti implants were divided into two control groups (A and B). ZrO2 implants manufactured from yttria-stabilized tetragonal ZrO2 polycrystal (Y-TZP) in group C, from Y-TZP dotted with alumina (Y-TZP-A) in group D, and from Y-TZP-A with a modified surface in groups E and F were used. In group F, the implant heads were prepared, and in group G, the implants were restored with ZrO2 crowns. Each group included 16 samples with the exception of group D, which included 24 samples. A subgroup of each implant type (eight implants) was subjected to thermomechanical cycling in a chewing simulator prior to fracture testing. Test specimens were then loaded until a fracture occurred. Results: Seven of the 120 samples failed in the chewing simulator. ZrO2 implant fracture occurred at 725 to 850 N when the implants were not prepared, and at 539 to 607 N when prepared. The samples in group A fractured at the level of the abutment screw. All ZrO2 implants fractured at the level of the Technovit® resin (Heraeus Kulzer GmbH & Co., Wehrheim, Germany). No fracture of the ZrO2 crowns in group G was observed. Conclusion: Mean fracture strength values obtained were all within the limits of clinical acceptance. However, implant preparation had a statistically significant negative influence on the implant fracture strength. Long-term clinical data are necessary before one-piece ZrO2 implants can be recommended for daily practice. [ABSTRACT FROM AUTHOR]

Background: A recently introduced implant, the NobelDirect (Nobel Biocare AB, Göteborg, Sweden), has previously been documented with substantial bone resorption in a large number of operated cases. PurposeL The aim of this study was to evaluate the failure rate of NobelDirect implants in a retrospective multicenter survey. Materials and Methods: A total of 550 NobelDirect implants consecutively placed in over 269 patients at 18 centers were evaluated with regard to failure rate after an average follow-up of about 1 year. Results: The overall failure percentage was 10.9% (59 failures). The 58 implants not loaded directly showed only one failure (1.7%) versus 58 failures (11.8%) of those implants that were loaded directly. A chemical x-ray photoelectron spectroscopy analysis of an implant from the original batch showed up to 3.5% silicon at parts of the implants. A retrieval analysis of one implant removed at 2 years after placement demonstrated bone resorption down to the level of the fifth thread. Conclusions: It is concluded that the NobelDirect implant, if placed with a punch procedure, ground down in situ, and loaded directly, shows an unusually high failure rate at 1 year. [ABSTRACT FROM AUTHOR]

Purpose: The aim of the present study was to compare the treatment outcome of TiUniteTM- and turned-surfaced Brånemark System® (Nobel Biocare AB, Göteborg, Sweden) implants when applying immediate loading of cross-arch designed fixed partial dentures in the anterior mandible. Materials and Methods: Fifteen patients with edentulous mandibles participated in the study. In one half of the jaw, between the exit of the nerve-vessel bundle and the midline, one type of implant was placed and in the remaining half the other type. The implants were loaded the day of surgery via a fixed, temporary supra-construction. Ten days later, the permanent one was screw retained to the implant pillars. Results: The present 18-month clinical trial failed to demonstrate any differences regarding healing and cumulative success rate of an an-oxidized implant surface (TiUnite) and a turned (turned) one when implants in the anterior mandible were exposed to functional load within 24 hours after installation. Conclusion: A high predictability regarding the treatment outcome for immediately loaded Brånemark implants in the anterior mandible was observed. Furthermore, no difference between the traditional turned and the an-oxidized implant surface (TiUnite) could be observed. However, it has to be stressed that all implants (irrespective of surface) were placed in the anterior mandible and also that all the patients demonstrated a high level of oral hygiene. [ABSTRACT FROM AUTHOR]

Background: Following connection to the oral cavity, osseointegrated dental implants and surrounding tissues are exposed to microbiologic and biomechanical challenges. The establishment of a firm functional periimplant soft tissue barrier (PSTB) is considered to be important to protect the implant's interface from invasion of bacteria. The current knowledge on the histologic architecture of the PSTB is mainly based on animal experiments. Purpose: The aim of this study was to histologically characterize the PSTB formed in humans around experimental one-piece mini-implants with different surface topography. Materials and Methods: Five patients received a total of 12 experimental titanium, one-piece mini-implants with an oxidized (n = 4), an acid-etched (n = 4), or a machined (n = 4) surface distal to therapeutic implants. Following transmucosal healing of 8 weeks and at abutment connection of the regular implants, the mini-implants were harvested with a layer of surrounding hard and soft tissue. The specimens were fixed and processed for histologic sectioning according to standard procedures. The most central bucco-oral section cut in the long axis was used for morphologic analyses of the PSTB. The vertical soft tissue morphology was quantified using histometric measurements. Results: The overall height of the soft tissue, that is, the biologic width, was around 4 to 4.5 mm and consisted of an epithelial and a supracrestal connective tissue barrier. The junctional epithelium established the attachment to the implant surface, whereas the collagen fibers and fibroblasts of the connective tissue seal were oriented parallel to the implant. The epithelial attachment was shorter at the oxidized and acid-etched surfaces compared with the machined surfaces. Accordingly, the oxidized and acid-etched mini-implants exhibited a longer zone of connective tissue seal. Conclusion: The periimplant soft tissue formed at the experimental one-piece mini-implants in humans was of a character similar to that described in animal studies. The oxidized and acid-etched implants revealed less epithelial downgrowth and longer connective tissue seal than machined implants. [ABSTRACT FROM AUTHOR]

Background: Many longitudinal studies of different implant systems have been published but few controlled randomized investigations have been reported. A 1-year report of a comparative study of ITI Dental Implant System® implants (Straumann AG, Waldenburg, Switzerland) and Brånemark System® implants (Nobel Biocare AB, Gothenburg, Sweden) has been published by the present authors. This paper is a 3-year follow-up of that randomized study. Purpose: The aim of the study was to compare the outcome of fixed partial prostheses supported by ITI or Brånemark implants. The outcome was evaluated primarily in terms of survival rates and changes in marginal bone level. Material and Methods: The study group comprised 28 patients with anterior residual dentition in the maxilla. The patients were provided with two to four implants on each side of the dentition and were randomly allocated to Brånemark implants or ITI implants; 77 ITI implants and 73 Brånemark implants were inserted. After 6 months abutment connections were made to both ITI and Brånemark implants. All patients were provided with fixed partial prostheses of gold-ceramic. The patients were followed up annually with clinical and radiographic examinations for 3 years. Results: Two Brånemark implants and two ITI implants were lost. The Brånemark implants were lost before loading whereas the ITI implants were lost because of periimplantitis. The survival rate for both groups was 97.3%. The mean marginal bone level of the Brånemark implants was situated 1,8 mm from the reference point at both the baseline and the 3-year examinations. The corresponding values for the ITI implants were 1.4 mm at baseline and 1.3 mm after 3 years. There was no significant difference between the implant systems with regard to bone level or bone level change. A steady state of the marginal bone level was calculated to have been reached after 3 years for 95.5% of the Brånemark implants and 87.1% of the ITI implants. Periimplantitis (infection including pus and bone loss) was observed with seven ITI implants but with none of the Brånemark implants. This difference was statistically significant. Conclusions: No statistically significant differences were found between the implants studied, except for the frequency of periimplantitis, which was higher for the ITI implants. The survival rates were high, and the marginal bone loss was small for both systems. [ABSTRACT FROM AUTHOR]

Presents a prospective study on mandibular overdentures supported by conical transmucosal and standard MK II implants. Information on the possible side effects of dental rehabilitation with traditional removable prostheses in cases of atrophic edentulous mandibles; Observation on the success rate for immediately loaded mandibular implants; Criteria used for determining success rate.

Presents a study which compared the outcome of fixed partial bridges in the maxilla supported by both ITI Dental and Brånemark implant systems. Prerequisites for dental implant insertion; Materials and methods used in the study; Criteria of implant survival.

Presents a study which examined the outcome of a simplified method of implant treatment in the edentulous lower jaw. Method for the evaluation of the marginal bone level of the patients; Assessment of implant failures in the study; Comparison between the survival rate of the one-stage and two-stage technique.

Background: Osseointegration may be described as a direct contact between living bone and an alloplastic implant. It is thought that a period of undisturbed healing is required to ensure osseointegration. The length of the healing period is dependent on a number of factors, such as implant material, surface configuration, site preparation technique, bone quality, healing capacity of the osteotomy, and implant design. Elimination of the healing period offers distinct advantages in terms of cost of therapy and convenience to patients. Recently, a new one-piece implant design was proposed that provides improved stability of the implant to allow immediate support of an interim prosthesis. Purpose: This article presents the initial clinical experiences when the Altiva Natural Tooth Replacement one-piece implant was used in a human clinical trial. Materials and Methods: This was a prospective multicenter study of the placement and immediate loading of the one-piece implant. A total of 142 implants were placed in the jaws of 93 patients. Implants were placed consecutively and were followed at specified intervals in three private clinical practices. Clinical performance was recorded relative to implant survival and prosthesis support. Results: The implant survival rate was 93.7%, with similar responses in the maxilla (95.0%) and the mandible (92.7%). When implant failure occurred, it was observed as mobility without infection within 3 to 5 weeks of implant insertion. Conclusions: On the basis of this trial, there is promising evidence that this implant design can succeed at rates similar to other designs that require conventional healing times. [ABSTRACT FROM AUTHOR]