Publications (19)42.9 Total impact
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Article: Chemisch modifizierte, ultra-hydrophile Titanimplantatoberflächen
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ABSTRACT: Kürzlich wurde eine chemisch modifizierte, ultra-hydrophile, sandgestrahlte und säuregeätzte (modSLA) Titanoberfläche, mit dem Ziel die Knochenanlagerung zu verbessern, vorgestellt. Vorläufige präklinische und klinische Untersuchungen deuten darauf hin, dass modSLA-Implantate die Knochenanlagerung während der initialen Wundheilung verbessern können. Diese positiven Effekte auf die Knochenregeneration könnten auf die hydrophilen Oberflächeneigenschaften zurückgeführt werden, welche eine Stabilisierung des Blutkoagulums im Wundbereich ermöglicht. Das Ziel des vorliegenden Übersichtsartikels ist es, basierend auf derzeitiger Evidenz, die potenzielle Bedeutung von modSLA-Oberflächen für die zahnärztliche Implantologie zu bewerten. Recently, achemically modified ultra-hydrophilic sand-blasted, large grit and acid-etched (modSLA) titanium surface has been introduced in order to enhance bone apposition. Indeed, preliminary preclinical and clinical data have indicated that modSLA implants may enhance bone apposition during early stages of wound healing. These positive effects on bone regeneration might be probably mainly due to the hydrophilic surface properties noted for modSLA which ensured astabilization of the blood clot. The aim of the present review article is to evaluate, based on the currently available evidence, the potential impact of modSLA surfaces for implant dentistry.Mund- Kiefer- und Gesichtschirurgie 04/2012; 11(1):11-17. -
Article: Biomechanical evaluation of a microstructured zirconia implant by a removal torque comparison with a standard Ti-SLA implant.
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ABSTRACT: The purpose of this study was to evaluate the biomechanical bone tissue response to novel microstructured zirconia implants in comparison to sandblasted and acid-etched (SLA) titanium implants through the analysis of removal torque (RTQ) measurements. Ti-SLA implants with a sandblasted, large-grit and acid-etched surface were compared with zirconia implants with an acid-etched surface. All implants had the same shape, a diameter of 4.1 mm and a length of 10 mm. A total of 136 implants were placed in the maxillae of 17 miniature pigs. Six animals were sacrificed after both 4 and 8 weeks and five animals were sacrificed after 12 weeks, thus providing a total of 102 implants for RTQ testing (34 implants were reserved for future histological analysis). The RTQ analysis was successfully performed, using a mixed model regression with P-values calculated using the nonparametric Brunner-Langer method, on 100 of the 102 implants, two were excluded from the analysis. The adjusted mean RTQ values for Ti-SLA implants were 131 Ncm (95%CI: 107-155) at 4 weeks, 128 Ncm (108-148) Ncm at 8 weeks, and 180 Ncm (153-207 Ncm) at 12 weeks of healing, whereas RTQ values for the zirconia implants were 110 Ncm (86-134), 97 Ncm (76-118) and 147 Ncm (121-174) at the corresponding time intervals. A comparison of the implant materials resulted in P-values of P = 0.114 at 4 weeks, P = 0.034 at 8 weeks and P = 0.105 at 12 weeks (significance set at P < 0.05). Within the limits of the present study, it could be confirmed that the biomechanical bone-tissue response of the investigated zirconia implants is non-inferior to that of the well-documented, roughened titanium surface, at each time point, within the set tolerance. There were no statistically significant differences between the two materials after a healing period of 4 and 12 weeks. The RTQ values of both implant types increased significantly from the 8-week to the 12-week time point.Clinical Oral Implants Research 11/2011; 23(10):1210-6. · 2.51 Impact Factor -
Article: Tissue integration of a new titanium-zirconium dental implant: a comparative histologic and radiographic study in the canine.
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ABSTRACT: This study evaluates a newly developed titanium-zirconium implant (TiZr), comparing it to a commercially available pure titanium (Ti) implant subjected to the same surface treatment. In nine dogs, 12 implants (six TiZr and six Ti) were randomly placed in the mandible with the implant shoulder at the bone crest and subjected to submerged healing. Standardized radiographs were taken after implantation, and at the sacrifice of 2 weeks (three dogs), 4 weeks (three dogs), and 8 weeks (three dogs). Histologic and histomorphometric measurements were performed on non-decalcified histologic sections. The main outcome measures included the first bone-implant contact (fBIC) and BIC over time. For statistical analysis, Wilcoxon signed-rank test and mixed model regressions were applied. From baseline to 8 weeks, a mean bone loss of 0.09 ± 0.33 mm for TiZr and a gain of 0.02 ± 0.33 mm for Ti were calculated radiographically. The number of implants with the fBIC coronal to the reference point (implant shoulder) gradually increased over time, reaching 39% of all TiZr implants and 50% of all Ti implants at 8 weeks. The mean fBIC values for Ti and TiZr were 0.29 ± 0.42 mm and 0.26 ± 0.32 mm (2 weeks), -0.01 ± 0.20 mm and 0.10 ± 0.28 mm (4 weeks), and -0.06 ± 0.22 mm and 0.08 ± 0.30 mm (8 weeks), respectively. The mean BIC values peaked at 86.9% ± 6.8% (8 weeks) for TiZr and at 83.4% ± 5.9% (4 weeks) for Ti. No statistically significant differences were observed at any time point. TiZr and Ti bone level implants with chemically-modified, sandblasted, and acid-etched surfaces performed similarly in regards to osseointegration in this unloaded canine study.Journal of Periodontology 10/2011; 82(10):1453-61. · 2.60 Impact Factor -
Article: Angiogenic activity of an enamel matrix derivative (EMD) and EMD-derived proteins: an experimental study in mice.
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ABSTRACT: To determine whether all or only certain proteins in an enamel matrix derivative (EMD) are angiogenic. The angiogenic effect was analysed using an in vivo angiogenesis assay. Silicon tubes were filled with or without potential and known angiogenic-modulating factors: (i) an EMD parent, (ii) nine pools of EMD proteins, (iii) fibroblast growth factor/vascular endothelial growth factor and (iv) amelogenin. Silicon tubes were implanted subcutaneously in mice. Dextran-fluorescein isothiocyanate (FITC) was injected via the tail vein, mice were euthanized and tubes were retrieved. Neovascularization was determined by measuring the amount of dextran-FITC within the tubes. The greatest angiogenic potential of the EMD parent was at a weight of 125 ng, resulting in a 4.3-fold increase compared with the negative control. Five pools of EMD proteins showed a stronger angiogenic activity than the EMD parent. Pool 5 showed the greatest angiogenic activity, when compared with the negative control (8.1-fold increase) and with 125 ng of the EMD parent (4.2-fold increase). Amelogenin demonstrated a significantly higher angiogenic activity than the negative control (increase up to 4.0-fold) and the EMD parent (increase up to 1.6-fold). EMD parent, recombinant porcine amelogenin and certain pools of EMD proteins induced significant angiogenesis compared with the controls using a standardized in vivo assay.Journal Of Clinical Periodontology 03/2011; 38(3):253-60. · 3.00 Impact Factor -
Article: Tissue Integration of a New Titanium-Zirconium Dental implant: A Comparative Histologic and Radiographic Study in the Canine.
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ABSTRACT: Background: A newly developed titanium-zirconium implant (TiZr) compared with a commercially available pure titanium (Ti) implant subjected to the same surface treatment is evaluated. Methods: In 9 dogs, 12 implants (6 TiZr, 6 Ti) were randomly placed in the mandible with the implant shoulder at the bone crest and subjected to submerged healing. Standardized x-rays were taken following implantation, and at the sacrifice of 2 weeks (3 dogs), 4 weeks (3 dogs), and 8 weeks (3 dogs). Histologic and histomorphometric measurements were performed on non-decalcified histological sections. The main outcome measures included the first bone-to-implant contact (fBIC) and the bone-to-implant contact (BIC). For statistical analysis, the Wilcoxon signed rank test and mixed model regressions were applied. Results: From baseline to 8 weeks, a mean bone loss of 0.09±0.33mm for TiZr and a gain of 0.02±0.33mm for Ti were calculated radio graphically. The number of implants with the fBIC coronal to the reference point (implant shoulder) gradually increased over time, reaching 39% of all TiZr implants and 50% of all Ti implants at 8 weeks. The mean fBIC values for Ti and TiZr were 0.29±0.42mm,and 0.26±0.32mm (2 weeks), -0.01±0.20mm and 0.10±0.28mm (4 weeks), and -0.06±0.22mm and 0.08±0.30mm (8 weeks), respectively . The mean BIC values peaked at 86.9±6.8% (8 weeks) for TiZr, and at 83.4±5.9% (4 weeks) for Ti. No statistically significant differences were observed at any time-point. Conclusions: TiZr and Ti bone level implants with a chemically modified sandblasted and acid etched surface performed similarly in regards to osseointegration in this unloaded canine study.Journal of Periodontology 02/2011; · 2.60 Impact Factor -
Article: Effect of enamel matrix derivative on proliferation and differentiation of osteoblast cells grown on the titanium implant surface.
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ABSTRACT: Enamel matrix derivative (EMD) is widely used in promoting periodontal regeneration, but the mechanisms underlying its effects are not entirely clear. In particular, the effect of EMD on osseointegration of dental implants and its application in the treatment of peri-implantitis are still debatable. The purpose of this study was to investigate the effect of EMD on proliferation and differentiation of osteoblasts grown on the Ti implant surface. Osteoblast-like MG-63 cells were seeded on coarse-grit-blasted and acid-etched surface Ti implant disks and stimulated with various EMD concentrations. Cell proliferation/viability, alkaline phosphatase activity, osteocalcin production, and expression levels of osteoprotegerin (OPG) and receptor activator of nuclear factor κB ligand (RANKL) were determined. EMD inhibited the proliferation/viability of MG-63 cells. Furthermore, EMD significantly increased the alkaline phosphatase activity and osteocalcin production in MG-63 cells grown on Ti surfaces. Finally, EMD enhanced mRNA expression level of OPG and did not influence that of RANKL. Application of EMD in the dental implantolology may have a positive effect on implant osseointegration, and further studies are required to improve clinical outcome.Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics 01/2011; 111(4):517-22. · 1.50 Impact Factor -
Article: Evaluation of a New Titanium-Zirconium Dental Implant: A Biomechanical and Histological Comparative Study in the Mini Pig.
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ABSTRACT: ABSTRACT Background: Titanium zirconium alloy with 13-17% zirconium (TiZr1317) shows significantly better mechanical attributes than pure Ti with respect to elongation and fatigue strength. This material may be suitable for thin implants and implant components exposed to high mechanical constraints. Purpose: The aim of this study was to test the hypothesis that TiZr1317 and Ti implants show comparable osseointegration and stability. Materials and Methods: The mandibular premolars (P1, P2, P3) and the first molar (M1) in 12 adult miniature pigs were extracted 3 months prior to the study. Six specially designed implants made from Ti (commercially pure, Grade 4) or TiZr1317 (Roxolid(R), Institut Straumann AG, Basel, Switzerland) with a hydrophilic sandblasted and acid-etched (SLActive, Institut Straumann AG, Basel, Switzerland) surface were placed in each mandible; three standard implants modified for evaluation of removal torque (RT) in one side and three bone-chamber implants for histologic observations in the contralateral side. RT tests were performed after 4 weeks when also the bone chamber implants and surrounding tissue were biopsied for histologic analyses in ground sections. Results: The RT results indicated significantly higher stability (p = 0.013) for TiZr1317 (230.9 +/- 22.4 Ncm) than for Ti implants (204.7 +/- 24.0 Ncm). The histology showed similar osteoconductive properties for both implant types. Histomorphometric measurements showed a statistically significant higher (p = 0.023) bone area within the chamber for the TiZr1317 implants (45.5 +/- 13.2%) than did the Ti implants (40.2 +/- 15.2%). No difference was observed concerning the bone to implant contact between the groups with 72.3 +/- 20.5% for Ti and 70.2 +/- 17.3% for TiZr1317 implants. Conclusion: It is concluded that the TiZr1317 implant with a hydrophilic sandblasted and acid-etched surface showed similar or even stronger bone tissue responses than the Ti control implant.Clinical Implant Dentistry and Related Research 06/2010; · 3.53 Impact Factor -
Article: Effect of Emdogain on proliferation and migration of different periodontal tissue-associated cells.
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ABSTRACT: Although Emdogain is widely used as a gel in periodontal therapy, the exact mechanisms underlying its regenerative ability still need to be further investigated. Therefore, we tested in vitro the effect of the product Emdogain on proliferation, viability, and migration of various human cell types of periodontium. Proliferation and viability of alveolar osteoblasts (AOBs), epithelial cell line HSC-2, and human umbilical vein endothelial cells (HUVECs) were measured using [(3)H]-thymidine uptake and 3,4,5-dimethylthiazol-2-yl-2,5-diphenyl tetrazolium bromide (MTT)-assay, respectively. Cell migration was investigated in microchemotaxis chamber. The proliferation and viability of AOB, HSC-2, and HUVECs were significantly stimulated by Emdogain (12.5-250 microg/mL) in direct relationship with the amount of product present in the cell culture medium. Cell migration was stimulated in AOB and HUVECs depending on Emdogain amount. In contrast, in HSC-2 cells the migration was stimulated only by less than 50 microg/mL of Emdogain, whereas at higher amounts this stimulating effect was either diminished or absent. Emdogain stimulates proliferation, viability, and migration of AOB, HSC-2, and HUVECs in vitro. This biological versatility of Emdogain could correspond to an essential mechanism underlying its ability to promote periodontal regeneration.Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics 06/2010; 109(6):924-31. · 1.50 Impact Factor -
Article: Effects of enamel matrix derivative on proliferation/viability, migration, and expression of angiogenic factor and adhesion molecules in endothelial cells in vitro.
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ABSTRACT: The aim of this study was to test in vitro the effect of enamel matrix derivative (EMD) on the proliferation/viability, migration, and expression of angiogenic factor and adhesion molecules in human umbilical vein endothelial cells (HUVECs). To date, discussions on angiogenic effects of EMD are rather controversial. The effect of EMD on the proliferation/viability of HUVECs after 24 hours was measured using 3,4,5-dimethylthiazol-2-yl-2,5-diphenyl tetrazolium bromide (MTT) assay and direct cell counting. Cell migration was observed in an especially adapted in vitro monolayer wound-healing model. The expression of angiogenic factor angiopoietin-2 (ang-2) and adhesion molecules intercellular adhesion molecule (ICAM)-1 and vascular endothelium-selectin (E-selectin) was quantified with real-time polymerase chain reaction (PCR). The proliferation/viability of HUVECs measured in MTT assay was stimulated by 0.1 microg/ml EMD and inhibited by higher doses (50 to 100 microg/ml), but the total number of cells was not affected. Cell migration in the wound-healing assay was promoted by EMD at doses of 0.1 to 50 microg/ml and inhibited at 100 microg/ml. The highest expression level of all three tested genes (ICAM-1, E-selectin, and ang-2) was observed at 50 microg/ml EMD. The results of the present in vitro study show the potential influence of EMD on the angiogenic activity of HUVECs, which may play an important role in periodontal tissue regeneration and wound healing.Journal of Periodontology 10/2009; 80(10):1622-30. · 2.60 Impact Factor -
Article: Bone response to loaded implants with non-matching implant-abutment diameters in the canine mandible.
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ABSTRACT: One way to evaluate various implant restorations is to measure the amount of bone change that occurs at the crestal bone. The objective of this study was to histologically evaluate the alveolar bone change around a bone-level, non-matching implant-abutment diameter configuration that incorporated a horizontal offset and a Morse taper internal connection. The study design included extraction of all mandibular premolars and first molars in five canines. After 3 months, 12 dental implants were placed at three levels in each dog: even with the alveolar crest, 1 mm above the alveolar crest, and 1 mm below the alveolar crest. The implants were submerged on one side of the mandible. On the other side, healing abutments were exposed to the oral cavity (non-submerged). Gold crowns were attached 2 months after implant placement. The dogs were sacrificed 6 months postloading, and specimens were processed for histologic and histometric analyses. Evaluation of the specimens indicated that the marginal bone remained near the top of the implants under submerged and non-submerged conditions. The amount of bone change for submerged implants placed even with, 1 mm below, and 1 mm above the alveolar crest was -0.34, -1.29, and 0.04 mm, respectively (negative values indicate bone loss). For non-submerged implants, the respective values were -0.38, -1.13, and 0.19 mm. For submerged and non-submerged implants, there were significant differences in the amount of bone change among the three groups (P <0.05). The percentage of bone-to-implant contact for submerged implants was 73.3%, 71.8%, and 71.5%. For non-submerged implants, the respective numbers were 73.2%, 74.5%, and 76%. No significant differences occurred with regard to the percentage of bone contact. Minimal histologic bone loss occurred when dental implants with non-matching implant-abutment diameters were placed at the bone crest and were loaded for 6 months in the canine. The bone loss was significantly less (five- to six-fold) than that reported for bone-level implants with matching implant-abutment diameters (butt-joint connections).Journal of Periodontology 05/2009; 80(4):609-17. · 2.60 Impact Factor -
Article: Ridge augmentation and maxillary sinus grafting with a biphasic calcium phosphate: histologic and histomorphometric observations.
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ABSTRACT: This retrospective study reports on histologic and histomorphometric observations performed on human biopsies harvested from sites augmented exclusively by biphasic calcium phosphate [BCP: hydroxyapatite (HA)/ tricalcium phosphate (TCP) 60/40] and healed for a minimum of 6 months. Five patients benefited from three augmentation regimens (i.e.: one-stage lateral augmentation; two-stage lateral augmentation; and two-stage sinus grafting). In all patients, a degradable collagen membrane served as a cell-occlusive barrier. Core biopsies were obtained from lateral as from crestal aspects 6-10 months after augmentation surgeries. For histologic and histomorphometric evaluations, the non-decalcified tissue processing was performed. The histological examination of 11 biopsies showed graft particles frequently being bridged by the new bone, and a close contact between the graft particles and newly formed bone was seen in all samples. The mean percentages of newly formed bone, soft tissue compartment, and graft material were 38.8% (+/-5.89%), 41.75% (+/-6.08%), and 19.63% (+/-4.85%), respectively. Regarding bone-to-graft contact values, the percentage of bone coverage of graft particles for all biopsies ranged from 27.83% to 80.17%. The mean percentage of bone coverage was 55.39% (+/-13.03%). Data from the present study demonstrated osteoconductivity scores for the BCP material (HA/TCP 60/40) in patients resembling those previously shown for grafting materials of xenogenic and alloplastic origin.Clinical Oral Implants Research 05/2009; 20(7):708-14. · 2.51 Impact Factor -
Article: Comparative study of biphasic calcium phosphates with different HA/TCP ratios in mandibular bone defects. A long-term histomorphometric study in minipigs.
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ABSTRACT: Three biphasic calcium phosphate (BCP) bone substitute materials with hydroxyapatite (HA)/tricalcium phosphate (TCP) ratios of 20/80, 60/40, and 80/20 were compared to coagulum, particulated autogenous bone, and deproteinized bovine bone mineral (DBBM) in membrane-protected bone defects. The defects were prepared in the mandibles of 24 minipigs that were divided into four groups of six with healing times of 4, 13, 26, and 52 weeks, respectively. The histologic and histomorphometric evaluation focused on differences in amount and pattern of bone formation, filler degradation, and the interface between bone and filler. Collapse of the expanded polytetrafluoroethylene barrier membrane into the coagulum defects underlined the necessity of a filler material to maintain the augmented volume. Quantitatively, BCP 20/80 showed bone formation and degradation of the filler material similar to autografts, whereas BCP 60/40 and BCP 80/20 rather equaled DBBM. Among the three BCP's, the amount of bone formation and degradation of filler material seemed to be inversely proportional to the HA/TCP ratio. The fraction of filler surface covered with bone was highest for autografts at all time points and was higher for DBBM than BCP 80/20 and 60/40 at the early healing phase. TRAP-positive multinucleated cells were identified on BCP and DBBM surfaces without showing typical signs of resorption lacunae.Journal of Biomedical Materials Research Part B Applied Biomaterials 01/2009; 90(1):171-81. · 2.15 Impact Factor -
Article: Histomorphometric assessment of bone formation in sinus augmentation utilizing a combination of autogenous and hydroxyapatite/biphasic tricalcium phosphate graft materials: at 6 and 9 months in humans.
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ABSTRACT: The aim of this study was to examine the efficacy of a new biphasic hydroxyapatite/tricalcium phosphate (HA/TCP) bone substitute in combination with particulate autogenous bone in sinus floor augmentation procedures. A simultaneous or a two-stage sinus augmentation and implant placement were conducted in 28 patients. A mixture of HA/TCP and autogenous bone chips in a 1 : 1 ratio was used as the grafting biomaterial. Cylindrical specimen bone retrieval was performed in all patients except one. Specimens were harvested either at 6 (n=14) or 9 (n=13) months post-augmentation. For histologic and histomorphometric evaluations, the non-decalcified tissue processing (Donath's technique) was performed. Newly formed bone around the grafted particles was found in all samples. The encircling, highly cellular bone followed the outline of the grafted particles in direct contact. Both woven and lamellar types of bone were observed. Morphometrically, the total mean bone area fraction of all sections was 34.8+/-10.3%, increasing from 28.6+/-7.8% at 6 months to 41.6+/-8.3% at 9 months (P<0.001). Mean particle area fraction average was 25.5+/-11.6% and 23.5+/-9.3% at 6 and 9 months, respectively, with a total mean of 24.5+/-10.4%. The increase in bone area fraction was not significantly correlated to the decrease of the grafted particles area fraction. The biphasic HA/TCP showed biocompatible and osteoconductive properties. This alloplast as a composite with autogenous bone chips promotes newly formed bone, which increases in its fraction along an extended healing period.Clinical Oral Implants Research 07/2008; 19(7):686-92. · 2.51 Impact Factor -
Article: Evaluation of a novel biphasic calcium phosphate in standardized bone defects: a histologic and histomorphometric study in the mandibles of minipigs.
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ABSTRACT: A novel biphasic calcium phosphate (CaP) granulate consisting of hydroxyapatite (HA) and beta-tricalciumphosphate (TCP) was compared with pure HA and pure TCP and with autograft as positive control. Four standardized bone defects were prepared in both mandibular angles of 16 minipigs and grafted with autogenous bone chips, HA, HA/TCP (60% : 40%), or TCP. Histologic and histomorphometric analysis of bone formation and graft degradation followed healing periods of 2, 4, 8, and 24 weeks. 2 weeks: more bone formation in defects filled with autograft than with the three CaP materials (P<0.05). 4 weeks: bone formation differed significantly (P<0.05) between all four materials (autograft>TCP>HA/TCP>HA). 8 weeks: more bone formation in defects with autograft and TCP than with HA/TCP (P<0.05), and HA/TCP had more bone formation than HA (P<0.05). 24 weeks: no difference in bone formation between the groups. Autograft and TCP resorbed quickly and almost completely over 8 weeks, whereas HA/TCP and HA showed limited degradation over 24 weeks. All defects healed with mature lamellar bone and intimate contact between bone and the remaining graft material. The rate of bone formation corresponded to the content of TCP in the CaP materials.Clinical Oral Implants Research 12/2007; 18(6):752-60. · 2.51 Impact Factor -
Article: Purification and analysis of a 5kDa component of enamel matrix derivative.
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ABSTRACT: High performance liquid chromatography (HPLC) methods were used to analyse a 5kDa component purified from enamel matrix derivative (EMD), the active ingredient in Emdogain, a commercial product for periodontal tissue regeneration. After initial purification by size-exclusion chromatography (SEC) on a 100 cm x 5 cm column (Bio-Gel P-30 Fine, 280 nm), collected fractions were analysed by size-exclusion HPLC (SE HPLC; TSK-Gel Super SW2000, 220 nm). The fractions containing only the 5kDa component were analysed by reversed-phase high-pressure chromatography (RP HPLC; YMC-Pack ODS-A, 200 nm), revealing four peaks of the 5kDa component. From 1200 mg of EMD (of which 9% is the 5kDa component), approximately 65 mg of lyophilised 5kDa component were obtained, corresponding to a recovery of 60%. The SE HPLC method was mainly suitable for qualitative analysis, whereas the RP HPLC method was appropriate for both qualitative and quantitative analysis.Journal of Chromatography B 11/2007; 857(2):210-8. · 2.89 Impact Factor -
Article: Histological and immunohistochemical analysis of initial and early subepithelial connective tissue attachment at chemically modified and conventional SLA titanium implants. A pilot study in dogs.
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ABSTRACT: The aim of the present pilot study was to histologically/immunohistochemically investigate initial and early subepithelial connective tissue attachment at transmucosal parts of modified (mod) and conventional sandblasted, large grit and acid-etched (SLA) titanium implants. Implantation of modSLA and SLA implants was performed bilaterally in both the mandible and maxilla of four beagle dogs. The implants were submerged to prevent bacterial contamination. The animals were killed after 1, 4, 7 and 14 days. Peri-implant tissue reactions were assessed histologically (Masson Goldner Trichrome stain-MG) and immunohistochemically (IH) using monoclonal antibodies to fibronectin (FN) and proliferating cell nuclear antigen (PCNA). The surgical procedure of implant submerging resulted in the formation of an artificial gap in the transmucosal area of both types of implants. After 14 days of healing, MG stain revealed the formation of well-organized collagen fibres and numerous blood vessels in a newly formed loose connective tissue zone adjacent to modSLA. While some fibres were oriented in a parallel direction, others have started to extend and attach partially perpendicular to the implant surface. In contrast, SLA implants appeared to be clearly separated by a dense connective tissue zone with parallel-running collagen fibres and rare blood vessel formation. First signs of a positive FN and PCNA staining adjacent to both implant surfaces were observed at day 4. Within the limits of a pilot study, it might be concluded that modSLA titanium surfaces might possess the potential to promote subepithelial connective tissue attachment at the transmucosal part of the implant.Clinical Oral Investigations 10/2007; 11(3):245-55. · 2.36 Impact Factor -
Article: Histological and immunohistochemical analysis of initial and early osseous integration at chemically modified and conventional SLA titanium implants: preliminary results of a pilot study in dogs.
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ABSTRACT: The aim of the present pilot study was to investigate initial and early tissue reactions to modified (mod) and conventional sand-blasted, large grit and acid-etched (SLA) titanium implants. Implantation of modSLA and SLA implants was performed bilaterally in both the mandible and maxilla of dogs. The animals were sacrificed after a healing period of 1, 4, 7 and 14 days, respectively. Peri-implant tissue reactions were assessed in non-decalcified tissue sections using conventional histology (Toluidine blue-TB and Masson Goldner Trichrome stain-MG) and immunohistochemistry using monoclonal antibodies to transglutaminase II (TG) (angiogenesis) and osteocalcin (OC). Bone density (BD) and bone to implant contact (BIC) were assessed histomorphometrically. Day 1 revealed an early TG antigen reactivity in the provisional fibrin matrix adjacent to both implant surfaces. Day 4 was characterized by the formation of a collagen-rich connective tissue (MG), which revealed the first signs of OC synthesis adjacent to modSLA surfaces. Immunohistochemical staining for TG revealed a direct correlation between angiogenesis and new bone formation, which was clearly identifiable after 7 days by means of increasing BD, BIC and OC values. After 14 days, modSLA surfaces seemed to be surrounded by a firmly attached mature, parallel-fibered woven bone. Within the limits of the present study, it might be concluded that the combination of immunohistochemical and conventional histological stainings in non-decalcified tissue sections is a valuable technique to evaluate the initial and early stages of wound healing around endosseous titanium implants.Clinical Oral Implants Research 09/2007; 18(4):481-8. · 2.51 Impact Factor -
Article: [Chemically modified, ultra-hydrophilic titanium implant surfaces].
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ABSTRACT: Recently, a chemically modified ultra-hydrophilic sand-blasted, large grit and acid-etched (modSLA) titanium surface has been introduced in order to enhance bone apposition. Indeed, preliminary preclinical and clinical data have indicated that modSLA implants may enhance bone apposition during early stages of wound healing. These positive effects on bone regeneration might be probably mainly due to the hydrophilic surface properties noted for modSLA which ensured a stabilization of the blood clot. The aim of the present review article is to evaluate, based on the currently available evidence, the potential impact of modSLA surfaces for implant dentistry.Mund- Kiefer- und Gesichtschirurgie 02/2007; 11(1):11-7. -
Article: Bone regeneration in dehiscence-type defects at chemically modified (SLActive) and conventional SLA titanium implants: a pilot study in dogs.
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ABSTRACT: The aim of the present study was to evaluate bone regeneration in dehiscence-type defects at titanium implants with chemically modified (mod) and conventional sand-blasted/acid-etched (SLA) surfaces. Standardized buccal dehiscence defects (height: 3 mm, width: 3 mm) were surgically created following implant site preparation in both the upper and lower jaws of four beagle dogs. modSLA and SLA implants were inserted bilaterally according to a split-mouth design. The animals were sacrificed after 2 and 12 weeks (n=2 animals each). Dissected blocks were processed for histomorphometrical analysis: defect length, new bone height (NBH), percent linear fill (PLF), percent of bone-to-implant contact (BIC-D) and area of new bone fill (BF). Wound healing at SLA implants was predominantly characterized by the formation of a dense connective tissue at 2 and 12 weeks, without significant increases in mean NBH, PLF, BIC-D or BF values. In contrast, modSLA implants exhibited a complete defect fill at 12 weeks following implant placement. In particular, histomorphometrical analysis revealed the following mean values at 12 weeks: NBH (3.2+/-0.3 mm), PLF (98%), BIC-D (82%) and BF (2.3+/-0.4 mm(2)). Within the limits of the present study, it was concluded that modSLA titanium surfaces may promote bone regeneration in acute-type buccal dehiscence defects at submerged implants.Journal Of Clinical Periodontology 02/2007; 34(1):78-86. · 3.00 Impact Factor
Top co-authors
Top Journals
Institutions
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2012
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Institut Straumann AG
Basel, BS, Switzerland
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2011
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University of Zurich
Zürich, ZH, Switzerland
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2010–2011
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Medical University of Vienna
Vienna, Vienna, Austria
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2009
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University of Texas Health Science Center at San Antonio
- Department of Periodontics
San Antonio, TX, USA
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2007
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Heinrich-Heine-Universität Düsseldorf
- Poliklinik für Zahnärztliche Chirurgie und Aufnahme
Düsseldorf, North Rhine-Westphalia, Germany
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