Background:
Early detection and monitoring of cognitive dysfunction in multiple sclerosis (MS) may be enabled with smartphone-adapted tests that allow frequent measurements in the everyday ...environment.
Objectives:
The aim of this study was to determine the reliability, construct and concurrent validity of a smartphone-adapted Symbol Digit Modalities Test (sSDMT).
Methods:
During a 28-day follow-up, 102 patients with MS and 24 healthy controls (HC) used the MS sherpa® app to perform the sSDMT every 3 days on their own smartphone. Patients performed the Brief International Cognitive Assessment for MS at baseline. Test–retest reliability (intraclass correlation coefficients, ICC), construct validity (group analyses between cognitively impaired (CI), cognitively preserved (CP) and HC for differences) and concurrent validity (correlation coefficients) were assessed.
Results:
Patients with MS and HC completed an average of 23.2 (SD = 10.0) and 18.3 (SD = 10.2) sSDMT, respectively. sSDMT demonstrated high test–retest reliability (ICCs > 0.8) with a smallest detectable change of 7 points. sSDMT scores were different between CI patients, CP patients and HC (all ps < 0.05). sSDMT correlated modestly with the clinical SDMT (highest r = 0.690), verbal (highest r = 0.516) and visuospatial memory (highest r = 0.599).
Conclusion:
Self-administered smartphone-adapted SDMT scores were reliable and different between patients who were CI, CP and HC and demonstrated concurrent validity in assessing information processing speed.
Objectives
Although titanium is commonly used as a favorable bone implant material due to its mechanical properties, its bioactive and osteoconductive capacity is relatively low. Calcium phosphate ...ceramics, predominantly hydroxyapatite (HA), have been frequently used for coating purposes to improve the bioactive properties. In view of the suggested osteopromotive capacity of bioactive glasses (BGs), this study aimed to evaluate the effect of BG incorporation into HA coatings on implant performance in terms of bone contact and bone area.
Materials and Methods
A total of 48 screw‐type titanium implants with magnetron sputter coatings containing different ratios of HA and BG (HA, HABGLow, and HABGHigh; n = 8) were placed into the mandible of 16 Beagle dogs. After 4 and 12 weeks, their performance was evaluated histologically and histomorphometrically. Peri‐implant bone area percentage (BA%) was determined in three zones (inner, 0–500 μm; middle, 500–1000 μm; and outer, 1000–1500 μm). Additionally, bone‐to‐implant contact (BIC%) and first bone–implant contact (1st BIC) were assessed for each sample.
Results
After 4 weeks, bone‐to‐implant contact for the HA‐ and HABGLow‐coated groups was significantly higher (P < 0.05) than for the HABGHigh coatings. Mean values for overall BA% showed comparable values for both the HABGLow (58.3%)‐ and HABGHigh (56.3%)‐coated groups. Data suggest that the relative BA around the HA‐coated implants (67.8%) was higher, although this was only significant compared to the HABGHigh group. After 12 weeks, all three groups showed similar bone‐to‐implant contact and no differences in BA were found.
Conclusions
The incorporation of BG into HA sputter coatings did not enhance the performance of a dental implant in implantations sites with good bone quality and quantity. On the contrary, coatings containing high concentrations of BG resulted in inferior performance during the early postimplantation healing phase.
Peri‐implantitis is an inflammatory disease of hard and soft tissues around osseointegrated implants, followed by a progressive damage of alveolar bone. Oral microorganisms can adhere to all types of ...surfaces by the production of multiple adhesive factors. Inherent properties of materials will influence not only the number of microorganisms, but also their profile and adhesion force onto the material surface. In this perspective, strategies to reduce the adhesion of pathogenic microorganisms on dental implants and their components should be investigated in modern rehabilitation concepts in implant dentistry. To date, several metallic nanoparticle films have been developed to reduce the growth of pathogenic bacteria. However, the main drawback in these approaches is the potential toxicity and accumulative effect of the metals over time. In view of biological issues and in attempt to prevent and/or treat peri‐implantitis, biomaterials as carriers of antimicrobial substances have attracted special attention for application as coatings on dental implant devices. This review will focus on biomaterial‐based possibilities to prevent and/or treat peri‐implantitis by describing concepts and dental implant components suitable for engagement in preventing and treating this disease. Additionally, we raise important criteria referring to the geometric parameters of dental implants and their components, which can directly affect peri‐implant tissue conditions. Finally, we overview currently available biomaterial systems that can be used in the field of oral implantology.
Objectives
This in vivo study with implants installed in the goat iliac crest was performed to determine whether the biological and mechanical properties of the bone‐to‐implant interface are ...influenced by (i) the type of implant anchorage (i.e., mono‐ vs. bicortical placement), and (ii) the presence of a bioactive hydroxyapatite (HA) or composite HA/bioactive glass (BG) coatings.
Materials and methods
A total of 96 titanium (Ti) implants w/‐ coatings (Ti, Ti‐HA & Ti‐HABG; n = 8) were mono‐ or bicortically placed in the iliac crest of eight goats. At installation and after 4 weeks, implant stability was determined using insertion and removal torque testing (ITQ & RTQ). The peri‐implant bone response was histologically and histomorphometrically evaluated by means of bone‐to‐implant contact (BIC%) and bone area (BA%).
Results
Monocortical implants demonstrated significantly lower RTQ values in comparison to ITQ values, whereas for bicortical implant placement RTQ and ITQ were similar. Further, mean RTQ values for monocortical implants were significantly lower in comparison to bicortical implants. Histomorphometrical evaluation demonstrated higher BIC% and BA% for bicortical implants compared to monocortical implants. For bicortical implants, BA% in the inner peri‐implant region (0–500 μm) was significantly higher compared to the middle (500–1000 μm) and outer (1000–1500 μm) region. Also, a significant correlation was observed for monocortical implants between RTQ and BIC% and BA%. For surface modifications, no significant differences were found in ITQ and RTQ, for neither mono‐ nor bicortical implants. Histomorphometrically, HABG‐coated implants demonstrated significantly higher BIC% compared to GAE surfaces for both mono‐ and bicortical implants. Bicortical HA‐coated implants revealed significant higher BA% in the inner peri‐implant region (0–500 μm) in comparison to bicortical GAE implants.
Conclusions
This study demonstrated that bicortical implant placement beneficially affects implant stability during the early phase of osseointegration. A significant correlation between removal torque and bone‐to‐implant contact and bone area for monocortical implants was observed, but not for bicortical implants. Therefore, histomorphometrical data should be interpreted with caution to predict the biomechanical implant fixation of bone implants over time. Regarding surface modifications, in the present implantation model, the addition of BG to an RF magnetron sputtered HA coating enhanced the biological behavior of the coating compared to grit‐blasted/acid‐etched implants.
Abstract The objectives of the current review were (1) to systematically appraise, and (2) to evaluate long-term success data of calcium phosphate (CaP) plasma-spray-coated dental implants in ...clinical trials with at least 5 years of follow-up. To describe the long-term efficacy of functional implants, the outcome variables were (a) percentage annual complication rate (ACR) and (b) cumulative success rate (CSR), as presented in the selected articles. The electronic search yielded 645 titles. On the basis of the inclusion criteria, 8 studies were finally included. The percentage of implants in function after the first year was estimated to be 98.4% in the maxilla and 99.2% in the mandible. The estimates of the weighted mean ACR-percentage increased over the years up to 2.6 (SE 0.7) during the fifth year of function for the maxilla and to 9.4 (SE 8.4) for the mandible in the tenth year of function. After 10 years, the mean percentage of successful implants was estimated to be 71.1% in the maxilla and 72.2% in the mandible. The estimates seem to confirm the proposed, long-term progressive bone loss pattern of CaP-ceramic-coated dental implants. Within the limits of this meta-analytic approach to the literature, we conclude that: (1) published long-term success data for calcium phosphate plasma-spray-coated dental implants are limited, (2) comparison of the data is difficult due to differences in success criteria among the studies, and (3) long-term CSRs demonstrate very weak evidence for progressive complications around calcium phosphate plasma-spray-coated dental implants.
Objective
The current study aimed to evaluate the osteogenic potential of electrosprayed organic and non‐organic surface coatings in a gap‐implant model over 4 and 12 weeks of implantation into the ...dog mandible.
Material and methods
Sixteen Beagle dogs received experimental titanium implants in the mandible 3 months after removal of left premolars (P2, P3 and P4). Three types of implants were installed in each animal: non‐coated implant, nano‐CaP coated implant and implant with type 1 collagen coating. Both micro‐CT and histomorphometry were used to evaluate peri‐implant bone response after implantation periods of 4 and 12 weeks. The bone area percentage was assessed histomorphometrically in three different zones (inner: 0–300 μm; middle: 300–600 μm; and outer: 600–1000 μm) around the implant surface. Bone‐bridging of the gap was also calculated for each sample.
Results
Four weeks after implantation, nano‐CaP and collagen‐coated implants showed significantly higher bone volume (BV) in the inner zone compared with non‐coated implants (P < 0.05 and P < 0.01). After 12 weeks, histomorphometric analysis showed comparable amounts of BV between all experimental groups. Also, no significant difference was found in the BV, as measured using micro‐CT, between the implant groups. Absolute bone ingrowth measurements were highest for collagen‐coated implants, but these differences were not significant.
Conclusion
The obtained data failed to provide a consistent favourable effect on bone formation of the collagen coating over 3 months of implantation. It is concluded that the source of the collagen as well as the limited osseous environment overshadowed a possible effect of the applied implant surface modifications. Similarly, the tested nano‐apatite surface coating did not improve peri‐implant bone ingrowth into a gap‐implant model.
Background
Calcium phosphate ceramic coatings have the potential to compensate for challenging bone conditions such as delayed or impaired bone healing and low bone quantity or density. Thus, the ...increasing universal prevalence of subjects with such challenging bone conditions might be paralleled by an enhanced global use of calcium phosphate ceramic‐coated dental implants. However, it is speculated that the long‐term clinical survival of calcium phosphate‐coated dental implants might be adversely affected by coating delamination.
Objective
The aims of the current review were (1) to systematically appraise and (2) to meta‐analyse long‐term survival data of calcium phosphate‐coated dental implants in clinical trials.
Materials and methods
An extensive search in the electronic databases of the National Library of Medicine (http://www.ncbi.nlm.nih.gov), The Cochrane Central Register of Controlled Trials and the ISI Web of Knowledge, was carried out for articles published between January 2000 and November 2011 to identify randomized controlled clinical trials, prospective clinical trials as well as retrospective analysis of cases (RA) presenting survival data on the topic of calcium phosphate‐coated dental implants. Only publications in English were considered, and the search was narrowed to studies in humans with a follow‐up of at least 5 years only. Furthermore, the reference lists of related review articles and publications selected for inclusion in this review were systematically screened. The primary outcome variable was percentage annual failure rate (AFR), and the secondary outcome variable was percentage cumulative survival rate (CSR).
Results
The electronic search in the database of the National Library of Medicine, The Cochrane Central Register of Controlled Trials and the ISI Web of Knowledge, resulted in the identification of 385 titles. These titles were initially screened by the two independent reviewers for possible inclusion, resulting in 29 publications suitable for further consideration. Screening the s led to 20 full‐text articles. From these articles, 15 reports were excluded. Finally, five of these original research reports could be selected for evaluation. No additional publications were identified by manual search. Thus, a total of five articles were included for analysis. Meta‐analysis revealed that neither AFRs of calcium phosphate‐coated dental implants increased progressively nor that long‐term CSRs for calcium phosphate‐coated dental implants were inferior to survival rates of noncoated implants.
Conclusion
We conclude that (1) published long‐term survival data for calcium phosphate‐coated dental implants are very limited, (2) AFRs of calcium phosphate‐coated dental implants do not increase progressively, and (3) long‐term CSRs for calcium phosphate‐coated dental implants are comparable to survival rates of noncoated implants.
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This study comparatively evaluated the osteophilic capacity of 17 different surface modifications (i.e. fourteen different chemical modifications via ceramic coatings and three ...different physical modifications via surface roughness) for titanium (Ti) surfaces. All surface modifications were subjected to physico-chemical analyses and immersion in simulated body fluid (SBF) for coating stability assessment. Subsequently, a bone conduction chamber cassette model on the goat transverse process was used for comparative in vivo analysis based on bone responses to these different surface modifications after twelve weeks. Histological and histomorphometrical analyses in terms of longitudinal bone-to-implant contact percentage (BIC%), relative bone area (BA%) were investigated within each individual channel and maximum bone height (BH). Characterization of the surface modifications showed significant differences in surface chemistry and surface roughness among the surface modifications. Generally, immersion of the coatings in SBF showed net uptake of calcium by thick coatings (>50μm; plasma-sprayed and biomimetic coatings) and no fluctuations in the SBF for thin coatings (<50μm). The histomorphometrical data set demonstrated that only plasma-sprayed CaP coatings performed superiorly regarding BIC%, BA% and BH compared to un-coated surfaces, irrespective of surface roughness of the latter. In conclusion, this study demonstrated that the deposition of plasma-sprayed CaP coating with high roughness significantly improves the osteophilic capacity of titanium surfaces in a chamber cassette model.
For the bone implant market, a large number of surface modifications are available on different types of (dental and orthopedic) bone implants. As the implant surface provides the interface at which the biomaterial interacts with the surrounding (bone) tissue, it is of utmost importance to know what surface modification has optimal osteophilic properties. In contrast to numerous earlier studies on bone implant surface modifications with limited number of comparison surfaces, the manuscript by van Oirschot et al. describes the data of in vivo experiments using a large animal model that allows for direct and simultaneous comparison of a large variety of surface modifications, which included both commercially available and experimental surface modifications for bone implants. These data clearly show the superiority of plasma-sprayed hydroxyapatite coatings regarding bone-to-implant contact, bone amount, and bone height.
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