Nobel Biocare AB Research Articles

Spontaneous progression of experimental peri‐implantitis at implants with different surface characteristics: An experimental study in dogs

To analyse spontaneous progression of ligature-induced peri-implantitis at implants with different surface characteristics. Four implants with similar geometry and with two different surface characteristics (turned/TiUnite; Nobel Biocare AB) were placed pairwise in one side of the mandible in five dogs, 3 months after tooth extraction. Experimental peri-implantitis was initiated by placement of ligatures and plaque formation. The ligatures were removed when about 40% of the supporting bone was lost. After 6 months, block biopsies were obtained and prepared for histological analysis. The amount of bone loss that occurred during the plaque accumulation period after ligature removal was significantly larger at implants with a TiUnite surface than at implants with a turned surface. The histological analysis revealed that the vertical dimensions of the lesion and the pocket epithelium and the apical extension of the biofilm were significantly larger at TiUnite implants than at turned implants. It is suggested that the implant surface characteristics influence progression of peri-implantitis.

“All‐on‐4” Immediate‐Function Concept for Completely Edentulous Maxillae: A Clinical Report on the Medium (3 Years) and Long‐Term (5 Years) Outcomes

Immediate implant function has become an accepted treatment modality for fixed restorations in totally edentulous mandibles, whereas experience from immediate function in the edentulous maxilla is limited. The purpose of this study was to report on the medium- and long-term outcomes of a protocol for immediate function of four implants (All-on-4, Nobel Biocare AB, Göteborg, Sweden) supporting a fixed prosthesis in the completely edentulous maxilla. This retrospective clinical study included 242 patients with 968 immediately loaded implants (Brånemark System TiUnite, Nobelspeedy, Nobel Biocare AB) supporting fixed complete-arch maxillary all-acrylic prostheses. A specially designed surgical guide was used to facilitate implant positioning and tilting of the posterior implants to achieve good bone anchorage and large interimplant distance for good prosthetic support. Follow-up examinations were performed at 6 months, 1 year, and thereafter every 6 months. Radiographic assessment of the marginal bone level was performed after 3 and 5 years in function. Survival was estimated at patient level and implant level using the Kaplan-Meier product limit estimation with 95% confidence intervals. Nineteen immediately loaded implants were lost in seventeen patients, giving a 5-year survival rate estimation of 93% and 98% at patient and implant level, respectively. The survival rate of the prosthesis was 100%. The marginal bone level was, on average, 1.52 mm (standard deviation [SD] 0.3 mm) and 1.95 mm (SD 0.4 mm) from the implant/abutment junction after 3 and 5 years, respectively. The high survival rates at patient and implant level indicates that the immediate-function concept for completely edentulous maxillae using the present protocol is viable in the medium- and long-term outcomes.

Long‐Term Function of Single‐Implant Restorations: A 17‐ to 19‐Year Follow‐Up Study on Implant Infraposition Related to the Shape of the Face and Patients' Satisfaction

Various levels of infraposition of single-implant restorations have been observed in long-term follow-up studies, but little knowledge is available on the biological mechanism behind this pattern. The primary aim of this study is to report the frequency and severeness of implant infraposition in the anterior single-implant application after 17 to 19 years in function and, secondly, to try to relate these observations to anatomical appearance of the shape of the face of the patient. The present study comprised of 57 patients who were provided with 65 CeraOne™ single-tooth restorations (Nobel Biocare AB, Gothenburg, Sweden) between 1989 and 1991. Altogether 46 of these patients were treated with single implants in the anterior region. Besides clinical and radiographic data, clinical photographs, study casts, and patient's assessment of the long-term aesthetic result (visual analog scale) was collected at the termination of the present study. The degree of implant crown infraposition was related to assessed facial shape and to patient and clinical assessment of the aesthetic result by means of Pearson's correlation test. To increase the numbers of patients, another group of 25 patients presented in another similar study were pooled with the present material for prevalence calculations. Altogether 47 patients showed up for the final examination after an average of 18 years (82%). Two implants failed (18 years cumulative survival rates [CSR]- 96.8%) and eight original single-crown restorations were replaced (CSR 83.8%). Three of the replaced crowns were replaced because of infraposition of the crowns. About 40% of the patients showed signs of infraposition, similar in younger and older age groups, but more frequently observed in female patients at termination of the study (p < 0.05). There was a weak trend indicating an association between "long-face" appearance and infraposition of the crown restoration (p > 0.05), and patients were more satisfied with the aesthetic clinical result than the participating clinicians (p < 0.05). Single-implant restorations in the anterior upper jaw may present small degrees of infraposition in long-term perspectives. Female patients seem to be at a higher risk of infraposition (p < 0.05), but no clear relationship between age at implant placement or facial shape and degree of infraposition was possible to establish (p > 0.05). Patients were more satisfied with the aesthetic result, as compared with the clinicians (p < 0.05), and patients seemed to pay less attention to the degree of infraposition in their aesthetic assessments, as compared with most of the clinicians.

Joining dental ceramic layers with glass

Objective Test the hypothesis that glass-bonding of free-form veneer and core ceramic layers can produce robust interfaces, chemically durable and esthetic in appearance and, above all, resistant to delamination. Methods Layers of independently produced porcelains (NobelRondo™ Press porcelain, Nobel BioCare AB and Sagkura Interaction porcelain, Elephant Dental) and matching alumina or zirconia core ceramics (Procera alumina, Nobel BioCare AB, BioZyram yttria stabilized tetragonal zirconia polycrystal, Cyrtina Dental) were joined with designed glasses, tailored to match thermal expansion coefficients of the components and free of toxic elements. Scanning electron microprobe analysis was used to characterize the chemistry of the joined interfaces, specifically to confirm interdiffusion of ions. Vickers indentations were used to drive controlled corner cracks into the glass interlayers to evaluate the toughness of the interfaces. Results The glass-bonded interfaces were found to have robust integrity relative to interfaces fused without glass, or those fused with a resin-based adhesive. Significance The structural integrity of the interfaces between porcelain veneers and alumina or zirconia cores is a critical factor in the longevity of all-ceramic dental crowns and fixed dental prostheses.

Simultaneous Le Fort I Osteotomy and Computer-Guided Implant Placement

Since 1977, osseointegrated implants have played a strong role in oral rehabilitation. Despite the large success of this technique for the edentulous maxilla and mandible with sufficient bone height, patients with atrophic jaws continue to be the challenging cases for an adequate reconstruction of aesthetics and functionality. Orthognathic surgical procedures have been developed to reposition the jaws and have been traditionally used in the dentate patient to correct a skeletal malocclusion; these procedures can be used on the edentulous patient to correct the discrepancies between the jaws followed by the placement of implants to rehabilitate the oral cavity. Recently, surgeons can use a computer-assisted software package that enables them to insert implants after a digital analysis of the residual alveolar and basal bone that makes for greater implant osseointegration. We describe a one-step oral rehabilitation with Le Fort I osteotomy and computer-guided implant placement to correct a posttraumatic deformity. The first step of the definitive treatment, the implant placement, was planned with the aid of a computer-assisted surgery software package (NobelGuide; Nobel Biocare AB, Goteborg, Sweden). Ten computer-planned implants (Nobel Biocare AB) were inserted (6 on the maxillary arch and 2 on each posterior area of the mandible). Simultaneously, the patient underwent a Le Fort I osteotomy to correct the maxillary deficiency without any bone grafts. The use of Le Fort I osteotomy as a preprosthetic procedure for the atrophic edentulous maxilla has been well accepted. This is a technically demanding procedure, and there are some described complications such as unfavorable fractures of the maxilla, oroantral fistulas, bone exposure, and low implant survival rates. However, in selected cases, this reconstructive method has the advantages over the other commonly used preprosthetic techniques of simultaneously allowing the placement of osseointegrated implants while correcting an unfavorable intermaxillary relationship and improving facial aesthetics. Computer-assisted surgery offers to the surgeons the possibility to visualize anatomic structures, evaluate implant position and inclination, insert accurately implants, prefabricate prosthesis, and avoid the morbidity of bone grafting procedures. One-step oral rehabilitation by Le Fort I and computer-guided implant placement can be used in selected patients. Despite the difficulty of this procedure, this approach enabled the authors to solve simultaneously a double problem: the malocclusion and the partially atrophic and edentulous jaws. According to the literature, this is the first case of a simultaneous Le Fort I osteotomy and computer-guided implant placement. The patient introduced had a posttraumatic deformity, but we think that this procedure could be extended in the future to manage other situations.

Influence of furrow width on the stability of titanium implants. A study in the rabbit

Aim Previous rabbit studies demonstrated higher affinity for bone formation at implant threads with furrows to threads without furrows. The present animal study was undertaken to study the bone tissue response and stability of oxidized titanium implants with 80, 110 and 160 I¼m wide furrows added on one thread flank. Materials and methods Ninety-six (96) threaded titanium implants, 3.75 mm in diameter and 7 mm long (TiUniteâ„¢, MKIII, Nobel Biocare AB, Gothenburg, Sweden), were manufactured with 70 I¼m deep and either 80 (S0), 110 (S1) or 160 (S2) I¼m wide furrows or no furrows (controls). The implants were installed in the distal femoral condyle and the tibial methaphysis of 12 rabbits. Six weeks later the implants were subjected to resonance frequency analysis (RFA) and removal torque (RTQ) tests, after ground sections were manufactured for light microscopy. Results A significantly increased (22%) stability of S1 implants in femoral sites compared with control implants was found. RFA showed no significant differences between test and control implants. Histology revealed more frequent bone fill of furrows with decreased width in parallel with increased frequency of fracture of the bone at the furrow entrance as opposed to a separation at the interface. Conclusion The present study demonstrated an increased and maximum rotational stability of oxidized titanium implants with a 110 I¼m wide furrow on one thread flank compared with control implants without a furrow. The observed increased stability can be explained by fracture of the bone at the entrance of the furrow as opposed to a separation at the interface as seen at the wider furrows and at control implants.

Accelerated Photo-Induced Hydrophilicity Promotes Osseointegration: An Animal Study

In the previous in vitro study, fluoride-modified, anodized porous titanium was proven to have enhanced its photo-induced hydrophilicity, which induced the hyperactivation of initial cell response. The purpose of the present study was to investigate in vivo bone apposition during the early stages of osseointegration in rabbit tibiae. Anodized porous titanium implants (TiU, TiUnite®, Nobel Biocare AB, Göteborg, Sweden) were modified with 0.175 wt% ammonium hydrogen fluoride solution (NH(4) F-HF(2) ). Twenty-four hours prior to the experiments, the surface-modified implants were ultraviolet-irradiated (modTiU). Blinded and unpackaged TiU implants were used as controls. Thereafter, the implants were placed in the rabbit tibial metaphyses and histomorphometrically analyzed at 2 and 6 weeks after insertion. ModTiU demonstrated a significantly greater degree of bone-to-metal contact than TiU after 2 and 6 weeks of healing. The results proved that the enhanced photo-induced hydrophilicity of the NH(4) F-HF(2) -modified anodized implants promoted bone apposition during the early stages of osseointegration.

Marginal Bone Level Changes at Dental Implants after 5 Years in Function: A Meta-Analysis

It is important that peri-implant bone breakdown caused by, for example, undue load and/or peri-implantitis, is prevented or minimized. Some continuous loss of marginal bone is generally accepted, but the question remains as to what extent it must occur. The purpose of this study was to compile and compare data on peri-implant marginal bone level changes from prospective studies that have registered the peri-implant marginal bone level radiographically at the time of prosthetic loading, and after 5 years of follow-up for implant systems currently available on the market. A literature search was carried out to identify prospective studies on peri-implant marginal bone level changes around dental implants. To be included in a meta-analysis, the implant systems should have been subjected to at least two independent studies. Copycats without documentation were not accepted. Forty prospective studies that presented with a 5-year data were identified. Three implant systems met the inclusion criteria of having at least two independent studies; Astra Tech Dental Implant System® (Astra Tech AB, Mölndal, Sweden), Brånemark System (Nobel Biocare AB, Göteborg, Sweden), and Straumann Dental Implant System (Institute Straumann AG, Basel, Switzerland). The pooled mean marginal bone level change amounted to -0.24 mm (95% CI -0.345, -0.135) for the Astra Tech Dental Implant System, 0.75 mm (95% CI -0.802, -0.693) for the Brånemark System, and 0.48 mm (95% CI -0.598, -0.360) for the Straumann Dental Implant System over 5 years, with a statistically significant difference (p < .01) between the systems. The identified implant systems showed an annual bone loss below or much below what hitherto has been set up as a limit for success. A careful documentation of marginal bone level changes should be mandatory for all implant systems before being marketed. It is also time for revision of existing success criteria to refine the basis for clinical quality judgment of implant treatment.

Computed tomography-guided implant surgery for dental rehabilitation in mandible reconstructed with a fibular free flap: description of the technique

The fibular free flap, with or without a cutaneous component, is the gold standard for reconstructing mandibular defects. Dental prosthetic rehabilitation is possible this way, even if the prosthesis-based implant is still a challenge because of the many anatomical and prosthetic problems. We think that complications can be overcome or reduced by adopting the new methods of computed tomography (CT)-assisted implant surgery (NobelGuide ®, Nobel Biocare AB, Goteborg, Sweden). Here we describe the possibility of using CT-guided implant surgery with a flapless approach and immediate loading in mandibles reconstructed with fibular free flaps.

Material degradation in implant-retained cobalt-chrome and titanium frameworks

The purpose of the study was to estimate in vitro material degradation in implants and cobalt-chrome or titanium frameworks, before and after exposure to artificial saliva. Four full-arch implant frameworks were fabricated according to the Cresco™ method (Astra Tech AB, Mölndal, Sweden), two in a cobalt-chrome alloy and two in commercially pure (CP) titanium. They were cut vertically, and the three central sections of each framework were used. Element leakage into an artificial saliva solution was observed with mass spectrometry. Before artificial saliva exposure, three Brånemark System(®) implants (Nobel Biocare AB, Gothenburg, Sweden) were screw-retained to cobalt-chrome sections, and three to titanium sections. The contact surfaces with the implants of the framework sections and the corresponding surfaces of six implants were examined with optical interferometry before and after exposure to artificial saliva to evaluate material degradation. Conventional descriptive statistics were used to present the mass spectrometry and interferometry data. One-way anova and Dunnett's T3 post hoc test were used to identify and study differences between the groups. To highlight changes within the groups, the Student's t-test was used. The significance level was set at 5%. There was significantly more leakage of cobalt elements than of titanium and chrome (P < 0·05). After saliva exposure and framework connection, the implants roughened (P < 0·05). The titanium frameworks were generally rougher than the cobalt-chrome frameworks, both before and after saliva exposure (P < 0·05). The findings in this study suggest active material degradation processes for both implants and framework materials.

Implant surface characteristics influence the outcome of treatment of peri-implantitis: an experimental study in dogs

To analyse the effect of surgical treatment of peri-implantitis without systemic antibiotics at different types of implants. Four implants representing four different implant systems - turned (Biomet 3i), TiOblast (Astra Tech AB), SLA (Straumann AG) and TiUnite (Nobel Biocare AB) were placed in the left side of the mandible in six dogs, 3 months after tooth extraction. Experimental peri-implantitis was initiated by placement of ligatures and plaque formation. The ligatures were removed when about 40-50% of the supporting bone was lost. Four weeks later, surgical therapy including mechanical cleaning of implant surfaces was performed. No systemic antibiotics or local chemical antimicrobial therapy were used. After 5 months, block biopsies were obtained and prepared for histological analysis. Two of the TiUnite implants were lost after surgical therapy. Radiographic bone gain occurred at implants with turned, TiOblast and SLA surfaces, while at TiUnite implants additional bone loss was found after treatment. Resolution of peri-implantitis was achieved in tissues surrounding implants with turned and TiOblast surfaces. Resolution of peri-implantitis following treatment without systemic or local antimicrobial therapy is possible but the outcome of treatment is influenced by implant surface characteristics.

Precision of Fit to Implants: A Comparison of Cresco™ and Procera® Implant Bridge Frameworks

The Cresco™ (Astra Tech AB, Mölndal, Sweden) method aims to reduce the inevitable distortions when cast metal frameworks for implant-supported prostheses are fabricated. However, limited data are available for the precision of fit for this method. To measure and compare the precision of fit of Cresco- and computer numeric controlled (CNC)-milled metal frameworks for implant-supported fixed complete prostheses. Two groups of frameworks were fabricated according to the Cresco method, either in titanium (Cresco-Ti, n = 10) or in a cobalt-chrome alloy (Cresco-CoCr, n = 10). A third group comprised CNC-milled titanium frameworks (Procera® Implant Bridge [PIB], Nobel Biocare AB, Göteborg, Sweden), made from individual model/pattern measurements (PIB, n = 5). Measurements of fit were performed by means of a coordinate measuring machine linked to a computer. The collected data on distortions were analyzed. Overall, a maximal three-dimensional range of center point distortion of 279 µm was observed for measured frameworks. The framework width (x-axis) decreased for Cresco-CoCr, but increased in Cresco-Ti and PIB; Cresco-CoCr compared to Cresco-Ti (p = .0002) and Cresco-CoCr compared to PIB (p < .0001). In vertical dimension (z-axis), less distortions were present in PIB compared to Cresco-CoCr (p = .0007) and in PIB compared to Cresco-Ti (p < .0001). None of the frameworks presented a perfect, completely "passive fit" to the master. Although the direction of distortions varied, the horizontal distortions were of similar magnitudes. However, the PIB frameworks had statistical significant less vertical distortions as compared to the Cresco groups.

A 10-year retrospective analysis of marginal bone-level changes around implants in periodontally healthy and periodontally compromised tobacco smokers

to compare the 10-year marginal bone loss rates around implants supporting single-unit crowns in tobacco smokers with and without a history of treated periodontitis. in this retrospective controlled study, 40 tobacco smokers were divided into four groups of 10 patients each. Two groups of periodontally compromised (PC) patients and two groups of periodontally healthy (PH) patients were established. PC patients had been treated for their periodontal conditions before implant placement. All patients were enrolled in a regular, individually tailored maintenance care program. For the rehabilitation of PC and PH patients, two different types of implants were used (Nobel Biocare AB; Straumann Dental Implant System). The radiographic bone loss rate was calculated by subtracting the bone levels at the time of crown delivery from the bone levels at the 10-year follow-up. the mean age, mean full-mouth plaque score and full-mouth bleeding score and implant location were similar for the four groups. Implant survival rates ranged between 70% and 100%, without statistically significant differences between the four groups (P>0.05). Implants placed in PC patients yielded statistically significantly higher marginal bone loss rates compared with those in PH patients (P<0.05), independent of the implant system used. after 10 years, implants placed in tobacco smokers with a history of treated periodontitis and enrolled in a supportive therapy program yielded lower survival rates and higher marginal bone loss rates compared with those of implants placed in PH smokers. These outcomes were independent of the implant system installed or the healing modality applied.

Four-Year Treatment and Radiographic Outcomes of 1-Piece Implants Used in Immediate Function: A Prospective Study in a Single Private Practice

The aim of this study was to prospectively evaluate treatment outcomes of 1-piece implants (NobelDirect and NobelPerfect, Nobel Biocare AB, Gothenberg, Sweden) in routine private clinical practice. Forty-seven implants placed in 30 subjects demonstrated a cumulative survival rate of 97.9% with stable marginal bone levels after 4 years of loading.

The Precision of Fit of Milled Titanium Implant Frameworks (I‐Bridge®) in the Edentulous Jaw

New computer numeric controlled (CNC)-milled frameworks for implant-supported prostheses have been introduced. However, no data are available on the precision of fit of these new frameworks. The purpose of this study is to evaluate the precision of fit of a new CNC-milled framework technique (I-Bridge, Biomain AB, Helsingborg, Sweden) using Brånemark System (Nobel Biocare AB, Göteborg, Sweden) and NobelReplace (Nobel Biocare AB) system implants. Ten test frameworks were fabricated for one master model for each implant system. Five additional frameworks were fabricated for five different models simulating clinical cases as controls (Brånemark System). The distortion of implant center point positions was measured in x-, y-, and z-axes and in three dimensions by using a contact-type coordinate measuring machine and a computer program developed specifically for this purpose. Mann-Whitney U-test was used to compare differences of distortion within and between the groups. The maximal distortion in arch width (x-axis) and curvature (y-axis) was within 71 and 55 microm for all frameworks, respectively. The mean distortion in absolute figures in x-, y-, z-axes and three dimensions was for "clinical control" frameworks 23, 26, 4, and 34 microm as compared with less than 12, 12, 2, and 17 microm for Brånemark and NobelReplace frameworks, respectively. Control frameworks showed significantly (p < .05) greater mean and range of distortions in x- and y-axes and in three dimensions compared with test frameworks. All measured frameworks presented signs of misfit, indicating that no framework had a "passive fit." Frameworks produced in a more routine clinical environment seem to present greater levels of distortion as compared with frameworks produced in a strict test situation. However, all measured frameworks presented levels of precision of fit within limits considered to be clinically acceptable in earlier studies of frameworks placed on abutments.

Marginal Bone Level Changes and Prosthetic Maintenance of Mandibular Overdentures Supported by 2 Implants: A 5‐Year Randomized Clinical Trial

Documentation of early loading of mandibular overdentures supported by different implant systems is scarce. This study aimed to compare the biologic and prosthetic outcome of mandibular overdentures supported by unsplinted early-loaded one- and two-stage oral implants after 5 years of function. Twenty-eight consecutive patients were screened following an inclusion and exclusion criteria, and randomly allocated to treatment groups. Ball-retained mandibular overdentures were fabricated on two unsplinted Straumann (Institut Straumann AG, Basel, Switzerland) and Brånemark (Nobel Biocare AB, Göteborg, Sweden) dental implants and subjected to an early-loading protocol. During the 5-year period, prosthetic complications were recorded. At 5-years of function, plaque, peri-implant inflammation, bleeding, and calculus index scores were recorded, and standard periapical radiographs were obtained from each implant for measurement of marginal bone loss. All implants survived during the observation period. The peri-implant inflammation, bleeding, and calculus index scores around Straumann and Brånemark implants were similar (p > .05). The marginal bone loss around Brånemark implants (1.21 +/- 0.1) was higher than Straumann implants (0.73 +/- 0.06) at 5 years of function (p = .002). Kaplan-Meier tests revealed that 1- and 5-year survival of overdentures on Straumann and Brånemark implants were similar (p = .85). Wear of the ball abutment in the Brånemark group was higher than in the Straumann group (p < .05). Complications regarding the retainer and the need for occlusal adjustments were higher in the Straumann group (p < .05). Chi-square test revealed that the frequency of retightening of the retainer was higher in the Straumann group than in the Brånemark group (p < .05). Mandibular overdentures supported by unsplinted early-loaded Straumann and Brånemark implants lead to similar peri-implant soft tissue and prosthetic outcomes, although higher marginal bone loss could be observed around Brånemark implants after 5 years.

Effect of Implant Design on Preservation of Marginal Bone in the Mandible

Implant design and surface may have an influence on the marginal bone response during immediate functional loading. The purpose of this study was to radiographically study the effect of implant design on marginal bone preservation at immediately loaded implants used for prosthetic rehabilitation of the completely edentulous mandible. A total of 39 patients, previously treated with five implants for support of a full-arch fixed bridge in the mandible, were included in the study. Either machined Brånemark implants (Ma) (Nobel Biocare AB, Gothenburg, Sweden) or surface modified Astra Tech implants with (Mi) or without a microthreaded neck (Ti) (TiOblast, AstraTech AB, Mölndal, Sweden) were used. All fixtures were loaded with a provisional glass fiber or metal-reinforced screw-retained restoration within 24 hours. The provisional restorations were replaced by a 12-unit screw-retained metal-ceramic or metal-resin cantilever bridge after 3 months. Bone loss from baseline to 1 year of loading was measured by means of intraoral radiographs. Only patients with baseline and 1-year radiographs of all implants were selected for comparison. Statistical analysis was carried out on both patient and implant levels. The survival rates after 1 year in function were 98.6, 100, and 100% for the Ma, Ti, and Mi implants, respectively. The overall mean bone loss after 1 year was 1.03 mm (SD 0.87; range -0.77 to 2.5). The mean bone loss was calculated to 1.52 (SD 0.66) for the Ma group, 0.79 (SD 0.79) for the Ti group, and 0.70 (SD 1.01) for the Mi group. There was a significant difference between Ma and Ti (p = .023) and between Ma and Mi (p = .046) groups but not within Ti and Mi implants (p = .70). These conclusions were also valid when the statistical analysis was performed on implant level. There is no impact of design and surface on implant survival in the completely edentulous mandible. Bone preservation in immediately loaded implants in the mandible is influenced by implant design and significantly better on surface-modified AstraTech implants compared with machined Brånemark implants. In the mandible, a microthread design of the implant collar does not seem to improve bone preservation.

Guided Surgery and Presurgical Prosthesis: Preliminary Results of 33 Fully Edentulous Maxillae Treated in Accordance with the NobelGuide® Protocol

The aim of this study was to present the preliminary results of 33 edentulous maxillary patients treated using the Nobelguide (Nobel Biocare AB, Göteborg, Sweden) technique. Thirty-three patients were treated according to the conventional protocol of the Nobelguide technique in two clinical centers. This group of patients received 211 implants. Monitoring was carried out for over 12-51 months, depending on the patient. The Nobelguide protocol was used for all patients. Of the 211 implants loaded, four were lost (1.9%). The implant survival rate was therefore 98.1%. The prosthetic survival rate was 100%. There were some per-operative complications (four) and some postoperative complications (10 fractures of resin). These preliminary results seemed rather promising. These were the first cases of experienced surgeons who needed to learn a new implant placement protocol. It was clear that analysis and understanding of the system were essential in order to obtain such a success. Only one implant was replaced without there being any impact on the prosthesis survival rate which is 100%.

Rehabilitation of Edentulous Mandibles by Means of Four TiUnite™ Implants after One‐Stage Surgery: A 1‐Year Retrospective Study of 75 Patients

ABSTRACTBackground: Recently, the present team reported the 1‐year data of a one‐stage surgery and mainly early loading with five supporting implants in completely edentulous mandibles, indicating more bone loss at the central implant, placed in the midline of the jaw.Purpose: The aim of the present retrospective investigation was to evaluate the 1‐year results of the same treatment technique with four instead of five supporting implants in completely edentulous mandibles. The outcome was compared with that of a former study (control) on five implants per patient during first year of function.Materials and Methods: The present study comprised 75 patients with a total of 300 TiUnite™ implants (Nobel Biocare AB, Göteborg, Sweden) of mainly the Brånemark System ≥ Mark III design. The prosthetic procedure started and was completed on an average of 9.1 days (standard deviation [SD] 4.47) and 33.2 days (SD 16.09) after the surgical intervention, respectively. Intraoral radiographs were obtained at prosthesis insertion and at the 1‐year follow‐up visit. Failure rates of test and control groups were compared by means of the chi‐squared test.Results: All four implants in one patient were found to be mobile at the first annual check‐up, resulting in an implant cumulative survival rate (CSR) of 98.5%. The corresponding CSR for the control group was 100% (p &gt; 0.05). The mean marginal bone resorption during the first year of function was 0.3 mm (SD 0.74) as compared with 0.5 (SD 0.56) mm for the control group (p &gt; 0.05).Conclusions: The outcome of 300 TiUnite™ implants placed in 75 patients with edentulous mandibles, of which 268 implants in 67 patients were followed for 1 year, showed an implant CSR of 98.5%. The implant survival was not significantly different from that of the control study result of 100%, in which five instead of four supporting implants were used. The levels of marginal bone were close to identical for the corresponding test and control implants at the 1‐year check‐up.

Clinical Experience of TiUnite™ Implants: A 5‐year Cross‐Sectional, Retrospective Follow‐Up Study

Little is known of the long-term clinical and radiographic performance of moderately rough surface implants. The aim of the present retrospective investigation was to study two pioneer cohorts of patients, that is, the first patients to receive Brånemark System implants with a moderately rough surface (TiUnite, Nobel Biocare AB, Göteborg, Sweden) at the present clinic. TiUnite implants were inserted either in compromised bone sites in a mixed-mouth concept together with turned implants or used solely. Patients were followed up over a period of 5 years with regard to implant survival and the marginal bone response. Patients who received both implant types (mixed group) comprised 41 subjects, and the second group (TiUnite group) comprised 70 subjects. A total of 110 turned and 68 TiUnite implants were placed in the mixed group, and 212 TiUnite implants in the TiUnite group. Follow-up radiographs were obtained at prosthesis placement and at the 1- and 5-year check-ups, and examined by independent observers. One turned (0.9%) and two TiUnite (2.9%) implants failed in the mixed group, and three implants (1.6%) failed in the TiUnite group, indicating no significant differences between surfaces or groups (p < .05). The mean marginal bone loss at 5 years was 0.6 mm to 0.8 mm, also indicating no significant differences for the two implant types tested in the mixed group. Cumulative survival rates for the two implant surfaces were favorable at 5 years, and the marginal bone loss was low and similar for both implant surfaces.