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Autogenous soft tissue augmentation procedures around natural teeth and dental implants are performed daily by clinicians. However, patient morbidity is often associated with the second surgical site; hence, research is moving toward an era where matrices may substitute autogenous grafts. The aim of this study was to assess the soft tissue response to a collagen matrix in an animal model. Nine pigs were included in this study. Each animal received four collagen matrices, two for each mandible. Three cohorts were included in the study: group A, where the matrix was applied as an onlay on a partial-thickness flap; group B, where the matrix was inserted under a partial-thickness flap; and group C, where the matrix was inserted in an inverted position under a full-thickness flap. Sacrifice occurred at 7, 15, and 30 days postoperatively for histologic assessment. The collagen matrix was seen in place for the first 2 weeks, and it was completely replaced by healthy connective tissue within 30 days in the inlay cohorts. No inflammatory adverse reactions were noticed in any specimen, resulting in optimal integration of the device. This study showed an optimal integration within 30 days postoperative of the placement of experimental collagen matrix in the soft tissues of an animal model. Its proven safety in this model provides an optimal starting point for further research projects considering its clinical applications.

Objectives: The fresh extraction socket in the alveolar ridge represents a special challenge in everyday clinical practice. Maintenance of the hard and soft tissue envelope and a stable ridge volume were considered important aims to allow simplifying subsequent treatments and optimizing their outcomes in particular, when implants are planned to be placed., Material and Methods: Prior to the consensus meeting four comprehensive systematic reviews were written on two topics regarding ridge alteration and ridge preservation following tooth extraction and implant placement following tooth extraction. During the conference these manuscripts were discussed and accepted thereafter. Finally, consensus statements and recommendations were formulated., Results: The systematic reviews demonstrated that the alveolar ridge undergoes a mean horizontal reduction in width of 3.8 mm and a mean vertical reduction in height of 1.24 mm within 6 months after tooth extraction. The techniques aimed at ridge preservation encompassed two different approaches: i) maintaining the ridge profile, ii) enlarging the ridge profile. Regarding timing of implant placement the literature showed that immediate implant placement leads to high implant survival rates. This procedure is primarily recommended in premolar sites with low esthetic importance and favorable anatomy. In the esthetic zone, however, a high risk for mucosal recession was reported. Hence, it should only be used in stringently selected situations with lower risks and only by experienced clinicians. In molar sites a high need for soft and hard tissue augmentation was identified., Conclusions: Future research should clearly identify the clinical and patient benefits resulting from ridge preservation compared with traditional procedures. In addition, future research should also aim at better identifying parameters critical for positive treatment outcomes with immediate implants. The result of this procedure should be compared to early and late implant placement., (© 2011 John Wiley & Sons A/S.)

In a typical microarray experiment, DNA is arrayed on a solid substrate as spots, the array being probed with a sample or a capture molecule of interest and the interaction monitored through different detection methods. The present study evaluates the possibility to use micro-array technology to genotype samples with Human Papilloma Viruses (HPV). The performance of DNA microarrays strongly depend on their surface properties. The efficiency of DNA immobilization in terms of sensitivity and specificity is one of the most important step in obtaining a microarray chip for diagnosis of HPV family viruses. Here we report the preparation and evaluation of nano-porous silicon surfaces for HPV detection based on DNA micro-array technique. Two different surfaces based on similar porous structure chemically modified in order to efficiently immobilize ss-DNA specific for HPV viruses were investigate.

Porous silicon (PS) layers with different degrees of porosity have been fabricated and their nanostructure has been investigated using complementary methods as FE-SEM (field emission scanning electron microscopy), SAXS (small-angle X-ray scattering), and Raman spectroscopy. Correlation of these results with strain analyses is also required for envisaged applications in MEMS technology. Symmetrical and asymmetrical rocking curves obtained by high-resolution X-ray diffraction completed with reciprocal space maps (RSMs) explain the features observed in Raman spectra: the PS film in-depth contains two layers-bulk and highly strained superficial layer, between them being a graded strain layer.

Objectives: The aim of the present study was to evaluate a Ca-P coated implant surface in a rabbit model. The Ca-P surface (test) was compared to the titanium porous oxide surface (control) in terms of bone-to-implant contact (BIC) and removal torque value., Materials and Methods: Two hundred and sixteen dental implants were inserted in the tibia and in the femur of 36 rabbits. One hundred and eight were represented by Ca-P oxidized surface implant and other 108 were titanium porous oxide surface modified implants. Each rabbit received six implants. Animals were sacrificed after 2, 4 and 9 weeks of healing. Each group included 12 rabbits. The femoral implant and the proximal implant of the tibia of each animal were subjected to the histologic analysis and the distal implants of the tibia underwent removal torque test (RTQ)., Results: Histological analysis in terms of BIC and RTQ did not revealed any significant difference between the Ca-P oxidized surface and the oxidized surface at 2 and 4 weeks. At 9 weeks, the oxidized surface demonstrated better results in terms of RTQ in the tibia., Conclusion: In conclusion, findings from the present study suggested that the Ca-P coating had no beneficial effect in improving bonding strength at the bone-implant interface either at 2, 4 and 9 weeks., (© 2010 John Wiley & Sons A/S.)

The goal of classifying complications in guided bone regeneration procedures with nonresorbable membranes is to provide the clinician with an instrument for easier identification of both the problem and treatment modality. A standardized terminology represents a key point for proper communication among clinicians and provides guidelines for managing these drawbacks.

Corneal wound healing is divided into several phases that, in reality are part of a continuous process, involving the corneal epithelium and stroma, corneal nerves, inflammatory cells, lacrimal glands. The layers of the cornea interact through autocrine and paracrine modulation, mediated by cytokines, growth factors, proteolytic enzymes. Corneal healing is affected by many factors, including: wound size and depth, causative agent, age, medication, preexisting diseases.

Diabetus mellitus is associated with numerous ocular complications. Diabetic keratopathy occurs in response to a neuropathy of the ophthalmic division of the trigeminal nerve, but also as a result of epithelial subclinical abnormalities, limbal vasculopathy and decrease in tear production. It comprises several symptomatic corneal conditions inducing superficial punctate keratopathy and persistent corneal epithelial erosions; the latter can progress to corneal ulceration and is often resistant to routine clinical management.

Background: In periodontal tissues, angiogenesis seems to be important for the maintenance of healthy tissues and in periodontal diseases. Angiogenesis is regulated through a complex interplay of molecular signals mediated by growth factors involving extracellular matrix remodeling, endothelial cell migration and proliferation, capillary differentiation and anastomosis. However, the influence of angiogenesis in the development, progression, and healing of periodontal lesions is currently under investigation. This immunohistochemical study evaluates the expression of vascular endothelial growth factor (VEGF), microvessel density (MVD), nitric oxide synthase (NOS) 1 and 3, and Ki-67 in gingival tissues of patients with aggressive and chronic periodontitis., Methods: Twenty-seven human gingival biopsies were taken from patients with chronic periodontitis (n = 14 patients), generalized aggressive periodontitis (n = 6 patients), and healthy periodontia (n = 7 patients). The specimens were immunohistochemically stained for VEGF, MVD, NOS 1 and 3, and Ki-67., Results: The levels of VEGF, MVD, NOS 1 and 3, and Ki-67 were found to be significantly different among groups (P >0.001). Patients with aggressive periodontitis had higher levels of these markers compared to those in patients with chronic periodontitis and healthy patients., Conclusions: The analysis demonstrates a higher expression of all immunologic markers particularly in subjects with aggressive periodontitis. In summary, the data from this pilot investigation suggests that VEGF is an important factor in the pathogenesis of the aggressive and chronic forms of periodontitis.

Porous silicon (PS) which has different properties from the bulk material due to the quantum confinement effects is beside other physical properties (e.g., light emitting) bioactive or even bioresorbable. The aim of this paper is to optimise the experimental conditions for the fabrication of nanostructured Si particles and to find the best methods for attaching on its surface molecules of therapeutic interest. The selective porosification has been performed using (i) a dielectric/metallic masking layer micropatterned with corresponding etching windows; (ii) a controlled diffusion process leading to n-type islands into p-type Si substrate. The PS particles were detached from the Si substrate by switching the electrochemical etching conditions from porosification towards the electropolishing regime. Also, similar results were obtained by fabrication of PS multilayer structures subjected to an additional ultrasonation process. Different organic molecules with antitumoral effect, such as chondroitin sulphate (a sulphated glycosaminoglycan), lactoferrin (globular protein with antimicrobial activity) and N-butyldeoxynojirimycin (an imino sugar that inhibits the growth of the CT-2A brain tumour) were covalently attached on the PS particle surface using 3-aminopropyltriethoxysilane (APTS) molecule as linker. Furthermore, to complete the administration/therapy of drugs, for microparticle targeting and imaging, Fe3O4 nanoparticles were integrated in PS matrix by co-precipitation from a solution of iron salts (Fe3+/Fe2+) in alkaline medium. Microscopic and spectroscopic analyses have been used to characterize the Si microparticles. Tumoral cells were cultivated on the nanostructured PS particles and a significant decrease of the cells density was observed on all investigated samples comparatively with the blank substrate without antitumoral molecules.

Aim: To evaluate the bone tissue response to zirconia implants with three different surface modifications in comparison with the oxidized titanium surface with the goal to optimize osseointegration in terms of strength and speed., Materials and Methods: A total of 18 rabbits with 143 implants were used. One hundred and twenty-three were threaded zirconia ceramic implants with three different surface topographies and 20 modified titanium oxide implants were controls. Each rabbit received eight implants and sacrificed after 3 weeks. The removal torque test (RTQ) and histology were performed., Results: Sixteen out of 18 rabbits completed the study with a total of 110 implants. No statistical significance was observed between the chemical modification implants compared with the topographically modified zirconia implant in terms of interfacial shear strength proven by the RTQ applied. No statistical significance was also observed in the bone-to-implant contact between the zirconia implants and the control oxidized implants., Conclusions: The findings suggest that additional specific chemical modifications of the topographically modified zirconia implants do not seem to enhance the bone-to-implant contact and appear not to increase the interfacial shear strength.

Emerging applications of porous silicon (PS) lies in its ability to incorporate other materials, such as organic groups, organic and inorganic nanoparticles to form (bio)hybrid systems where each individual constituent may be optimized for a particular function. This paper presents our recent experimental results on the fabrication and applications in biosensing of the porous silicon (PS) based microstructures. We have demonstrated that different morphologies of PS, either as-prepared or coated with gold nanoparticles have an important role in biomolecule detection, due to its large internal surface combined with specific electro-optical properties, being in the same time support for immobilization of complementary biomolecules as well as transducer for biochemical interactions. Therefore, we have investigated the photoluminescence properties of nanoporous Si prepared on different Si micropatterned surfaces comparatively with PS/flat Si in order to develop a new simple and versatile process for biosensor transducer fabrication. Meso- and macro-PS have been investigated for protein immobilization and detection using microarray technique or for DNA biomolecule detection by impedance spectroscopy. Finally, we have demonstrated that macroporous silicon constitutes an appropriate substrate for very sensitive SERS biosensors. RAMAN signal of 11-mercaptoundecanoic acid was investigated on Au/macroporous silicon. Various characterisation techniques have been used, optical and scanning electron microscopy (SEM) to investigate samples morphology, X-ray diffraction for nanoparticle structure, Raman and PL spectroscopy, and laser fluorescence detection for chemical and optical properties analysis and impedance spectroscopy for investigation organic molecule attachment on the Au/PS structures.

Objectives: The aim of this cohort study was to evaluate the safety and the acceptability of an electric toothbrush used on the peri-implant mucosa of implants placed in the aesthetic area., Methods: One hundred consecutive patients rehabilitated with implants positioned in the maxillary aesthetic area were recruited. Implants had to be restored at least 6 months prior to baseline. At baseline, subjects were provided with Oral-B Professional Care 7000 and received appropriate instructions to brush twice a day over a 12-month period. Papillary bleeding index, recession and probing depth were measured at baseline and at 3, 6, and 12 months., Results: Ninety-eight (98) patients completed the study. There was an overall reduction of recession (mean 0.2 mm) of borderline statistical significance. All of the changes occurred at the first followup visit (P=0.09) and persisted thereafter. The statistical analyses regarding the probing depth found a highly significant decrease over time (mean 0.3 mm). The bleeding score showed a gradual decrease over time, with a reduction at 12 months by more than half (0.65) in comparison with the baseline (1.50) and was shown to be highly significant (Wilcoxon sign-rank test: P < 0.001). No patient showed adverse effects such as ulcerations or desquamation. A high score of satisfaction by the patients using the electric toothbrush was reported (94% would continue to use it)., Conclusion: The electric toothbrush Oral B Professional Care 7000 appears to be safe for patients with fixed prosthesis on implants in aesthetic areas. Successive randomised clinical trials are needed to compare this instrument with other therapeutic devices for mechanical plaque control.

Objective: To evaluate, from a histological and histomorphometrical perspective, the efficacy of a 1 : 1 mixture of deproteinized bovine bone mineral (DBBM) and autogenous bone graft associated with an expanded-polytetrafluoroethylene (e-PTFE) membrane for vertical ridge augmentation in the human., Material and Methods: Seven patients with 10 surgical sites requiring vertical ridge augmentation of partially edentulous lower jaws were included in the study. The vertical augmentation procedure was performed combining a titanium-reinforced e-PTFE Gore-Tex membrane with a composite graft consisting of a 1 : 1 ratio of DBBM (Bio-Oss) and autogenous bone. Twenty-seven Branemark implants have been inserted. Eleven biopsies from the regenerated area were analyzed histologically and histomorphometrically., Results: The healing period was uneventful in nine surgical sites. In one site the membrane showed an exposure after 3 months. At the abutment connection, all implants appeared stable and submerged by a hard regenerated tissue clinically similar to bone. The histological analysis showed new bone formation and ongoing remodelling of the autogenous bone and the DBBM particles., Conclusions: The findings from the present clinical and histological study support the use of a 1 : 1 combination of DBBM and autogenous bone chips for vertical ridge augmentation by means of guided bone regeneration techniques. The regenerated bone may lead to proper osseointegration of a dental implant inserted at the time of the regenerative procedure or after a healing period of at least 6 months. DBBM undergoes very slow resorption and substitution with new bone. Furthermore, long-term clinical studies are needed to confirm the positive effect of DBBM in enhancing the lasting stability of the vertically augmented bone.

Unlabelled: Guided bone regeneration (GBR) has been used extensively since its introduction in the late 1980s. In such treatment, e-PTFE membranes are often preferred because of their inert biological features and the predictability of the barrier effect. One complication of GBR is the premature exposure of the membrane. A consequence of the resulting soft tissue dehiscence is compromised bone regeneration. There are situations in which an exposed membrane can be maintained and obtain satisfactory results. This article discusses suggested guidelines for the treatment of exposed e-PTFE membranes., Learning Objectives: This article discusses treatment options for e-PTFE membranes that are exposed with or without infection. Upon reading this article, the reader should: Be able to identify both Class I and Class II exposures. Understand how to properly treat both a Class I and Class II exposed e-PTFE membrane.

Aim: To evaluate the effect of using guided bone regeneration (GBR) with a titanium-reinforced e-PTFE membrane in alveolar bone defects with titanium implants., Material and Methods: Following extraction of three mandibular premolars and a molar on both sides of the jaw in three dogs, alveolar bone defects (depth: 5-7 mm) were produced. After 4 months, three implants were inserted into each defect to a depth of approximately 4 mm, so that their coronal portion was protruding about 5 mm. Four sides in the dogs were assigned to a test group and the remaining two sides to a control group. The 12 implants in the test group were covered with a reinforced e-PTFE membrane. The space under the membrane was filled with peripheral venous blood from the animal, and the flaps were sutured over the membrane. The six control implants received no membrane before the suturing of the flaps to complete wound closure. The animals were sacrificed after 6 months, and non-decalcified histological specimens of the implants and surrounding tissues were prepared., Results: Histologic and histomorphometric analyses revealed a significantly (Mann-Whitney test; P=0.08) larger amount of bone fill in the test group (mean=57.42%) than in the controls (mean=11.65%), and clinical evaluation of one test site showed that the implants were completely covered with tissue resembling bone. In most of the specimens, bone had grown in height close to, or in direct contact with the membrane. However, the new bone generally was not in direct contact with the implants. Regularly, a zone of dense connective tissue was interposed between the implants and the newly formed bone., Conclusion: The formation of even considerable amounts of bone following vertical ridge augmentation with GBR and implants was not accompanied by predictable osseointegration of the implants.

This clinical study retrospectively evaluated, after 1 to 7 years of prosthetic loading, 38 implants consecutively placed in 16 surgical sites, where severe atrophy of the posterior maxilla was treated by combining sinus elevation with the vertical ridge regenerative procedure. Two different surgical techniques were adopted. In seven patients (16 implants), implants were placed at the same stage as the regenerative procedures. In the other seven patients (22 implants), implant placement was performed at second-stage surgery, after 6 to 13 months of submerged membrane healing. Each implant was classified as a success, survival, or failure. The distance between the top of the implant shoulder and the first visible bone-implant contact was assessed radiographically for every implant at the mesial and distal sides. Two membranes became exposed during the healing process (12.5%). In the remaining 14 sites (87.5%), the membrane remained covered for a 6- to 13-month healing period. The survival rate of the implants was 92.1%, whereas the success rate was 76.3%. Three implants (7.9%) failed. A comparison of the implant shoulder-bone-implant contact distances between abutment connection and the last examination showed a mean crestal loss of 1.65 mm at the mesial side and 1.68 mm at the distal side. The bone regenerated vertically by means of sinus floor elevation and vertical ridge augmentation showed the same biologic behavior as native, nonregenerated bone; however, in a few cases, its remodeling pattern seemed to determine slightly higher bone crest resorption.

The aim of this article is to investigate 2 groups of biomaterials widely used in the surgical procedures for bone regeneration in dentistry: autograft and xenograft bone. An insufficient bone volume is the main condition for the long life stability of osteointegrated implants. Thanks to the numerous surgical procedures and fervent research, the possibility to rebuild the bone is now much more predictable than in the past. This has provided the clinician with more solutions to handle complex situations. In the last decade, the demand for regenerative surgery for functional and aesthetic reasons has increased. The autogenous bone graft is considered the gold standard material for any regeneration procedures, because of its main properties: it is osteogenetic, osteoinductive and osteoconductive. The autogenous bone can be harvested from 2 different sites: the intraoral and the extraoral sites. Intraoral donor site are the symphysis of the mandible, the mandibular ramus and the maxillary tuberosity. Extraoral donor site are the iliac crest, the tibia and the skull. The xenogeneic bone graft is a graft that has been taken from a donor of another species. These natural materials, thanks to their chemical-physical characteristics similar to those of the human bone, show great osteoconductive properties.

Objectives: To compare the electromyographic (EMG) characteristics of masticatory muscles in patients with fixed implant-supported prostheses and implant overdentures., Material and Methods: Nineteen subjects aged 45-79 years were examined. Fourteen were edentulous and had been successfully rehabilitated with (a) maxillary and mandibular implant-supported fixed prostheses (seven patients); (b) mandibular implant overdentures and maxillary complete dentures (seven patients). Five control subjects had natural dentition or single/partial (no more than two teeth) tooth or implant fixed dentures. Surface EMG of the masseter and temporal muscles was performed during unilateral gum chewing and during maximum teeth clenching. To reduce biological and instrumental noise, all values were standardized as percentage of a maximum clenching on cotton rolls., Results: During clenching, temporal muscle symmetry was larger in control subjects and fixed implant-supported prosthesis patients than in overdenture patients (analysis of variance, P=0.005). No differences were found in masseter muscle symmetry or in muscular torque. Muscle activities (integrated areas of the EMG potentials over time) were significantly larger in control subjects than in implant-supported prosthesis patients (P=0.014). In both patient groups, a poor neuromuscular coordination during chewing, with altered muscular patterns, and a smaller left-right symmetry than in control subjects were found (P=0.05). No differences in masticatory frequency were found., Conclusion: Surface EMG analysis of clenching and chewing showed that fixed implant-supported prostheses and implant overdentures were functionally equivalent. Neuromuscular coordination during chewing was inferior to that found in subjects with natural dentition.

The purpose of the present study was to evaluate retrospectively, after 1 to 5 years of prosthetic loading, 123 implants consecutively inserted at the time of vertical ridge augmentation in 4 clinics. At the time of the implant surgery, 3 different techniques were used: the implants were allowed to protrude 2 to 7 mm from the bone level and a titanium reinforced expanded-polytetrafluoroethylene (e-PTFE) membrane was positioned to protect either the blood clot (Group A, 6 patients), or an allograft (Group B, 11 patients), or an autograft (Group C, 32 patients). The annual implant evaluation was carried out according to a standard protocol utilized for long term studies with endosseous implants inserted in non-regenerated bone. Only 1 implant failed immediately after the second stage surgery and after 1 month it was substituted with a new implant. All the remaining implants appeared clinically stable, no signs of radiolucency were present at the bone-implant interface, therefore, they could be defined successfully osseointegrated. The radiographic analysis showed stable bone crest levels with a mean bone loss of 1.35 mm for the Group A, of 1.87 mm for the Group B and of 1.71 for the Group C during the period of observation. Only 2 implants demonstrated an increased crestal bone loss of 3.5 mm and 4 mm respectively at the first year examination. On the base of these results, we can confirm previous long term studies on regenerated bone and we can conclude that vertically augmented bone with GBR techniques responds to implant placement like native, non-regenerated bone.

In common practice a perfect fit of the prosthetic framework with the implant abutments is almost impossible to achieve. The mismatch, which is principally induced by the technological process adopted to manufacture the fixed prostheses, strains the framework thus generating constraint reactions. These are static forces that load the implant components and the bone at the implant-bone interface and may cause the bone remodelling. Depending on the magnitude of such forces, i.e. depending on the magnitude of the mismatch, the bone remodelling may lead to the loosening of the screws and of the implant-bone interface and hence cause implant failure. The present study shows an in vitro comparison of 3 different connecting abutments (standard, EsthetiCone and CerAdapt, Nobel Biocare AB, Göteborg, Sweden) with relation to the mechanical stresses induced by geometrical mismatches (technology induced errors). Two experimental devices were purposely realized and used to assess the ability of the different abutments to compensate errors. One was designed for translation errors and the other for rotation errors. The experimental apparatus set-up includes 2 freestanding implants supporting a prosthetic structure and the connecting abutments. The implants and the abutments were used as delivered by the manufacturer, while the prostheses were purposely realized and instrumented with strain gauges. The data obtained with the error devices do not give quantitative information on what happens in clinical applications where the implants are connected to living bone, which is a tissue much more deformable than the steel used for the error devices. Results allow direct comparisons of the behaviour of the different investigated abutments with respect to position errors. The CerAdapt system (cement retained ceramic abutments) showed the least strain in presence of translation errors. The standard system (screw retained abutments) showed the least strain in presence of rotation errors.

The aim of this study was to compare the characteristics of the bone-to-implant interface of hydroxyapatite-coated and non-coated commercially pure titanium threaded implants after different periods of healing in humans. To eliminate possible variations of the results from differences in bone quality and in surgical techniques used in the different test and control sites, only one half of each implant was coated with hydroxyapatite. The coated portions of the implants showed a tendency toward a higher percentage of direct bone-to-implant contact at each period of healing that was observed, although the small number of specimens does not allow definitive conclusions to be made.

Purpose: This is a 2-year report from an ongoing prospective 5-year multicenter study. The aim of the study was to evaluate the short- and long-term clinical function of CerAdapt ceramic abutments supporting short-span fixed partial dentures (FPD)., Materials and Methods: Initially, 105 Brånemark System implants were placed in a total of 32 patients at 3 different clinics. After initial healing 103 implants remained. For the support of 36 FPDs, 53 ceramic and 50 titanium abutments were connected, 19 on ceramic and 17 on titanium abutments., Results: All patients remained in the study after 2 years. There was a cumulative survival rate of 97.1% for implants and a cumulative success rate of 97.2% for FPDs (94.7% for ceramic and 100% for titanium abutment-supported FPDs). One of 53 ceramic but none of 50 titanium abutments failed, giving a cumulative success rate of 98.1% and 100%, respectively, for the abutments. Soft tissue around abutments and adjacent teeth appeared healthy. More crown margins were placed submucosally at titanium (31%) than at ceramic (14%) abutments, and the level of the periimplant mucosa was relatively stable in relation to the abutment/crown. No differences were seen between ceramic and titanium abutments regarding bleeding of the periimplant mucosa. There was a minimal marginal bone loss recorded after 1 year, which was slightly more at titanium (0.4 mm) than at ceramic (0.2 mm) abutments. All patients and dentists were satisfied with the achieved esthetic result and no FPD was remade because of compromised esthetics., Conclusion: So far the ceramic abutments have worked very well and the 2-year results have been very encouraging for CerAdapt abutments supporting short-span FPDs. However, ceramic materials tend to undergo static fatigue, and it is therefore important to wait for the 5-year results before making any more definite statement about the long-term prognosis for CerAdapt abutments.

The purpose of the present study was to compare the effect of 3 types of titanium reinforced e-PTFE membranes (GTRM #1, #2, and #3) on bone regeneration and tissue integration. GTRM #1 was a standard titanium reinforced membrane, GTRM #2 was a prototype characterized by a more open total surface microstructure and GTRM #3 was a prototype characterized by two extremely porous external layers separated by a totally occlusive internal layer. The membranes were used to cover saddle type ridge defects surgically created in the mandible of 6 dogs. After a healing period of 6 months, all the membrane protected sites demonstrated almost complete osseous healing of the defects. GTRM #3 specimens showed the most favourable biologic response, in fact they were characterized by a larger surface of contact between the membrane and the regenerated bone, but from a clinical point of view GTRM #3 material was too difficult to remove. The results of this study suggest that an extremely open porous microstructure, in combination with a totally occlusive barrier, may provide significant improvements in regenerative outcomes. However, these design characteristics may be applied only to resorbable devices, which do not require removal.

This issue propose an inventory of the methods of investigation which help for the diagnosis of the optic neuropathies. These investigation methods are shortly presented, and the situation in which there are usefull are presented. Some of these investigation are expensive and are not available in any ophthalmological hospitals. Despite of the great number of investigations, the problem of the etiopathogenesis of the optic neuropathies is not completely elucidated.

A lack of information exists about the influence of different implant abutment materials on bacterial colonization and its role in the development of perimplantar infections. In order to study these aspects, removable acrylic devices, harboring samples of titanium and novel ceramic abutments (Nobel Biocare) were adapted to the molar-premolar region in 2 mandibular quadrants of 4 volunteers. Samples of each material were collected at 6 and 24 h, 7 and 14 days. Samples were observed by scanning electron microscopy and bacterial counts were made by means of ATP detection and direct plate count. The electron micrographs demonstrated that the bacteria colonization was already present after 6 h of presence in the oral cavity. After 24 h, both the materials were covered by several layers of bacterial cells. No differences in microbial colonization were observed between titanium and ceramic samples. The microbiological analysis confirmed the presence of relevant amounts of microbial cells on the tested samples. The maximum of colonization was achieved after 24 h in the oral cavity and the bacterial counts remained constant over the 14 day period. No significant differences were observed between the two materials analyzed in this study. In addition, ATP-bioluminescence technology was demonstrated to be a suitable system to evaluate bacterial colonization in the oral cavity.

This study evaluated the clinical, radiographic, and histologic response to Bio-Oss porous bone mineral when used alone or in combination with Bio-Gide bilayer collagen membrane in human periodontal defects. Four intrabony periodontal defects were treated: two received Bio-Oss alone and two were treated with a combination of Bio-Oss and Bio-Gide. Radiographs, clinical probing depths and attachment levels were obtained preoperatively and 6 to 9 months postoperative, and teeth and surrounding tissues were biopsied. Both treatments significantly improved clinical probing depths and attachment levels, and the radiographic appearance suggested osseous fill. Histologic evaluation revealed that both treatments produced new cementum with inserting collagen fibers and new bone formation on the surface of the graft particles; this regenerative effect was more pronounced using the Bio-Oss/Bio-Gide combination, which resulted in 7 mm of new cementum and periodontal ligament and extensive new bone incorporating the graft. The membrane was intact at 7 months and partially degraded by 9 months after treatment. This human histologic study demonstrates that the porous bone mineral matrix used has the capacity to stimulate substantial new bone and cementum formation and that this capacity is further increased when the graft is used with a slowly resorbing collagen membrane.

The purpose of the present investigation was to study the histological morphology of the e-PTFE membrane/tissue interface in 5 humans subjected to GBR treatment in conjunction with oral implant treatment. Oral implants (Brånemark System) were inserted in extraction sockets 1 to 2 months after extraction of periodontally diseased teeth. The implants were placed approximately 2 mm below the surrounding bone margins. Specially designed 3 mm high cover-screws with horizontal slits for tissue ingrowth were applied to the implants and covered with e-PTFE membranes (GoreTex Augmentation Material). Re-entry was made 7 months later, except in 1 case where the membrane was removed 1 month postoperatively due to exposure and infection. In the remaining 4 sites, circular biopsies comprising membranes, tissues and cover-screws were retrieved. The specimens were fixated, processed and sectioned for light- and transmission electron microscopy. The space between the membrane and the cover-screw was occupied by fibrous tissue and varying amounts of bone. A cell- and vessel-rich fibrous tissue separated the bone from the membrane in the majority of the specimens. The membrane itself was penetrated by fibrous tissue. Fibroblasts and macrophages were the main cell types found in the fibrous tissue. The presence of irregularly shaped cells and unevenly distributed collagen fibres, indicated that the absence of bone formation may be due either to micromovements in the e-PTFE/tissue interface or to formation of fibrous tissue underneath the membrane by penetrating fibroblasts or a combination of these 2 phenomena.

This study investigated the effect on vertical bone regeneration of the addition of demineralized freeze-dried bone allograft or autogenous bone chips to a membrane technique. Twenty partially edentulous patients with vertical jawbone deficiencies were selected for this study. The patients were divided into two groups of 10 individuals. The 10 patients of Group A received 26 Brånemark implants in 10 surgical sites. The 10 patients of Group B received 32 implants in 12 surgical sites. Fifty-two out of 58 implants (22 in Group A and 30 in Group B) extended 1.5 to 7.5 mm superior to the bone crest. Titanium-reinforced expanded polytetrafluoroethylene membranes were used to cover the implants and, before complete membrane fixation, demineralized freeze-dried bone allograft particles were condensed under the membrane in Group A, and autogenous bone chips were used in Group B. At the reentry after 7 to 11 months the membranes were removed and a small biopsy was collected from 11 sites comprehending the miniscrews. The clinical measurements from Group A demonstrated a mean vertical bone gain of 3.1 mm (SD = 0.9 mm, range 1 to 5 mm) with a mean percentage of bone gain of 124% (SD = 46.6%). The measurements from Group B showed a mean vertical bone gain of 5.02 mm (SD = 2.3 mm, range 1 to 8.5 mm) with a mean percentage of bone gain of 95% (SD = 26.8%). Histomorphometric analysis of the present study clearly demonstrated a direct correlation between the density of the pre-existing bone and the density of the regenerated bone. The mean percentage of new bone-titanium contact was from 39.1% to 63.2%, depending on the quality of the pre-existing bone. Both the clinical and histologic results indicate a beneficial effect of the addition of demineralized freeze-dried bone allograft or autogenous bone particles to vertical ridge augmentation procedures in humans.

This study was carried out to evaluate the efficacy of poly(lactic acid) and poly(glycolic acid) (PLA/PGA) resorbable membranes in conjunction with autogenous bone grafts when used for the treatment of implant dehiscences and/or fenestrations. Nine patients with a total of 18 implants participated. Nine implants were associated with dehiscences, and 9 with fenestrations; 16 implants were in the maxilla, and 2 in the mandible. Nine defects were treated with PLA/PGA membranes (test group), and the nine were treated with expanded polytetrafluoroethylene (e-PTFE) membranes (control group). Second-stage surgery was performed after 6 to 7 months of healing. Overall results of the regenerative therapy of the 18 defects showed a highly significant (P < .001) defect reduction, with a 93.38% (SD = 15.88) bone fill. A slightly higher percentage of bone fill was found in the e-PTFE group (98.20%) than in the PLA/PGA group (88.56%), but the difference was not statistically significant (P = .207). This study demonstrated that resorbable PLA/PGA membranes can be equally effective as e-PTFE in the treatment of implant dehiscences and fenestrations when associated with autogenous bone chips.

Resorbable membranes of poly(lactic acid) and poly(glycolic acid) (PLA/PGA) were compared to nonresorbable expanded polytetrafluoroethylene (e-PTFE) membranes in the treatment of defects around titanium dental implants placed in postextraction sockets. Two partially edentulous and three completely edentulous patients requiring implant-supported restorations participated. Sixteen Brånemark implants were placed into extraction sockets and covered with modified titanium cover screws, called harvest cover screws, which allow tissue biopsy at second-stage implant surgery. Seven defects were treated with PLA/PGA membranes, five were treated with e-PTFE membranes, and four were left untreated (control sites). After 6 months of healing, the harvest cover screws were retrieved and processed for light microscopy examination together with the regenerated tissues. Very little or no bone formation was detected in control specimens. The e-PTFE membranes were found to be the most effective barrier material, in that denser and a greater amount of regenerated bone was found. The PLA/PGA membranes produced some bone regeneration when compared to control sites, but to a lesser extent compared to e-PTFE sites.

As a result of a fracture to the cemented post and core, a pure titanium implant was extracted from a 54-year-old patient after 4 years of clinical loading. At implantation, the implant was positioned into an extraction socket and the defect was treated with an e-PTFE membrane associated with a DFDBA graft. At retrieval the implant underwent histologic and histochemical examination to assess the characteristics of the regenerated bone after 4 years of prosthetic loading. The implant showed an angular bony defect at the smooth collar, but the bone-implant direct contact rate seemed to be elevated in the remaining implant surface. Normal transmitted and polarized light examinations demonstrated that most of the DFDBA particles were resorbed and substituted by vital newly formed bone. The regenerated bone appeared compact with secondary osteons and large haversian canals; however, some partially mineralized remnants residuated in the spaces, between the osteons. Within the limits of this study, the authors concluded that DFDBA can be substituted by the host bone, but the rate of substitution is very slow and not complete after 4 years. From a clinical point of view, however, the load-bearing capacity of the bone regenerated with the membrane technique associated with DFDBA appeared to be similar to that of normal bone.

The purpose of this study was to evaluate: (1) the surgical protocol, effectiveness, and reliability for vertical ridge augmentation using a new titanium-reinforced membrane and osseointegrated implants; and (2) the histologic characteristics of the interface between a pure titanium implant and newly regenerated human bone. Five patients received 15 conical Brånemark-type implants in six different surgical sites requiring vertical augmentation. The implants protruded 4 to 7 mm from the bone crest. Pure titanium miniscrews (1.3 x 10 mm) were positioned distally to the implants, protruding 3 to 4 mm from the bone level. The implants and the miniscrews were covered with a titanium-reinforced membrane, and the flaps were sutured. Membranes were removed at the stage 2 surgery after 9 months of healing. Measurements of biopsy specimens showed a gain in bone height from 3 to 4 mm. Histologic examination showed that all retrieved miniscrews were in direct contact with bone. Histomorphometric analysis of bone contact gave a mean value of 42.5 +/- 3.6% for five of the six examined miniscrews. The results suggest that the placement of implants protruding 3 to 4 mm from the top of resorbed bone surfaces may result in vertical bone regeneration to the top of the implant cylinder and that the regenerated bone is able to osseointegrate pure titanium implants.

This study compared, in a human model, the ability of (1) expanded polytetrafluorethylene (e-PTFE) membranes plus bone-chip autografts, (2) e-PTFE membranes plus demineralized freeze-dried bone, (3) e-PTFE membranes plus a new form of demineralized allograft bone tissue, and (4) e-PTFE membranes alone to enhance bone regeneration around dental implants placed into recent extraction sockets. The histologic results demonstrated that, in humans, guided tissue regeneration techniques are capable of producing new bone osseointegrated with titanium dental implants. Among the graft materials, autogenous bone provided the densest and the greatest amount of bone formation, but use of demineralized freeze-dried bone and a new form of de-mineralized allogenic bone matrix also improved bone regeneration compared to membranes alone after 6 months of healing.

Five patients with sufficient vertical bone height but insufficient bone width for implant placement were chosen for treatment with a split-crest technique combined with guided tissue regeneration. The surgical technique involved splitting the alveolar ridge longitudinally in two parts, provoking a greenstick fracture. A chisel was then used to make a fine cut and spread apart the two cortical plates. Implants were then placed. Implants and defects were covered with expanded polytetrafluoroethylene membranes. Biometrical examination showed a gain in bone width, varying between 1 and 4 mm; maxillary sites showed greater ridge enlargement. Histologic examination showed regeneration of bone tissue between the two portions of the split crest. This membrane technique could be effective and predictable for horizontal ridge augmentation associated with immediate implant placement.

After a careful review of literature Authors consider from a critical point of view efficacy of surgical versus non surgical therapy in one case of Rapidly Progressive Parodontitis. Data collected two years after the treatment have not shown significant differences between the two kinds of therapy.