Journal of long-term effects of medical implants最新文献

Carrageenans are the sulfated polysaccharides, extracted from the extracellular matrix of red seaweeds. Peri-implantitis is a pathological condition occurring in tissues around dental implants. Management of peri-implantitis should be concerned with control of infection, detoxification of the implant site and regeneration of alveolar bone. The goal of our study was to develop a membrane infused with carrageenan and fucoidan silica nanoparticles for guided bone regeneration around implant sites. Carrageenan (2%) was boiled for 2 min and 5% of fucoidan were added and boiled at 60°C and further 4000 μL of PEG was added, then film casting of membrane was done. 10 ml of silica nanoparticles were mixed in 0.1 g of SiO2 nanoparticles and were added to prepared carrageenan and fucoidan solution. Then film casting was done and air dried for 24 h. Antimicrobial assay, antioxidant activity, swelling and degradation analysis, FTIR test, tensile strength testing and SEM analysis were performed. The antimicrobial effect of carrageenan membrane showed better inhibitory effect against Streptococcus mutans. Antioxidant activity of the membrane infused with carrageenan and fucoidan silica nanoparticles shows 52.93 ± 0.35 SC effect percentage. The maximum force of tensile stress at break for carrageenan fucoidan incorporated with silica nanoparticles was about 5.76 MPa and for control sample membrane was 4.34 Mpa. Carrageenan and fucoidan based silica nanoparticles developed membrane showed good tensile strength and proven to have better antimicrobial, antioxidant activity with water absorption capacity which can be effectively used for guided bone regeneration around implant sites.

The objective of this in vitro study was to evaluate the elemental composition of commercially available dental implant drills using the positive material identification testing (PMI), its influence on corrosion resistance and longevity. Three implant drills each from 5 different implant systems (Groups I to V) were included in the study. Positive material identification testing, a technique of non-destructive testing using X-ray diffraction was carried out to evaluate the elemental composition of each drill system in percentage and grade testing of the alloy used for manufacturing the drills. Groups I and II had the maximum Chromium content of 17.09%Cr and 16.09%Cr. Group IV had a minimum of 11.67%Cr. Nickel content was maximum in Group III. Groups I and II belonged to Ferritic stainless steel alloys while Groups III, IV, and V were Martensitic stainless steel alloys. Ferritic stainless steel alloy drills (Groups I and II) were vulnerable to corrosion and wear compared to Martensitic stainless steel alloy drills (Groups III, IV, and V) with repeated surgical use. Incorporation of newer elements in stainless steel alloys is essential to promote corrosion resistance and drill longevity.

Implant dentistry is a widely utilized treatment approach for fully or partially edentulous patients. To enhance the success rates of dental implants, various surface modifications have been developed. This study aimed to compare clinical and radiographic parameters in patients with sandblasted acid-etched versus anodized surface dental implants. In this prospective clinical study, 78 patients who had undergone implant placement for missing single posterior tooth in mandible using sandblasted acid-etched and anodized surface dental implants during August 2019-December 2019 were enrolled according to strict inclusion and exclusion criteria and were categorized into Group 1: SLA (n = 27), Group 2: SLActive (n = 26), Group 3: TiUnite (n = 25) based on the surface modification of the implants. Peri-implant probing depth (PPD) and crestal bone loss (CBL) measurements were carried out at 3 months and 1-year intervals. For intergroup comparison, one-way ANOVA and Tukey's HSD post hoc test were used. For intragroup comparison, paired t test was used. PPD and CBL in Group 3 implants was significantly higher than Groups 1 and 2 (P ≤ 0.05). On pairwise comparison, there was a statistically significant difference in PPD and CBL between the groups at baseline (P ≤ 0.05) and 1-year follow-up (P ≤ 0.05) except for Group 1 vs. Group 2 at 1-year follow-up (P > 0.05). Intragroup comparison of PPD and CBL showed that there was a statistically significant difference from baseline in all the three groups in terms of PPD (P ≤ 0.05) and CBL (P ≤ 0.05). Patients with anodized dental implants exhibited greater PPD and CBL compared with those with sandblasted acid-etched implants.

Introduction: This study evaluated whether drill shape and bone preparation influences the primary stability of the implant using resonance frequency analysis and insertion torque values.

Materials and methodology: In this study, four most common, commercially available drill systems were used in this study. Bovine bone was chosen for the study. All the implants were chosen of the same dimension (3.5 mm ȕ 13 mm) to avoid bias and error. For convenience the study was divided into two parts. Part I of the study included performing osteotomy per manufacturer's instructions with a variability in the speed of the drilling at 300 rpm and 800 rpm, respectively. All the implants were placed at bone level, which was checked by taking radiographs. The primary stability of the implants of all the four different companies were measured using an ISQ machine (Penguin, Sweden). Part II of the study involved single drilling kit for the study. Sequential drilling protocol is selected for the second part of the study. All the four-implant system are placed using the same set of drill system. The implants are placed at 300 rpm. ISQ values are recorded using RFA machine (Penguin, Sweden) for each implant. IOPA was also recorded for the study.

Results: The results were subjected to analysis.

Conclusion: The results of this study suggest that implant drill shape did not have any significant effect on the overall primary stability of the implant. However, in certain implants, due to their unique design, custom drilling kits might be more feasible to use.

Intramedullary nail is the gold standard for treating long bones diaphysial fractures. Although the Fixion nail (Disc-O-Tech Medical Technologies Ltd., Herzliya, Israel) is an alternative technique to this method which constitutes an expandable nail, which is used to gain surgical time due to the absence of locking screws. In our department, 28 patients with tibial, femoral and humeral shaft fractures were treated by the expandable nail system for 18 months. Operative time, radiation exposure and healing time were recorded. Follow-up was obtained for a minimum of 1 year with an average of 14 months. Furthermore, in this study, we demonstrated a systematic review of the existing literature regarding the outcomes of studies on the use of the Fixion nail. In our case series, we observed one pseudarthrosis of a femoral fracture treated with a retrograde nail and two infections in tibia's fractures. In two cases, during the nail insertion, we had a failure of the implant (deformation of the tip (apex) of the nail) and two cases with delayed unions. The average operating time was 30 min (range, 26-34 min) for the tibia, 45 (range, 35-50 min) for the femur, and 20 min (range, 15-25 min) for the humerus. The radiation exposure was 0.20-0.50 s. During the systematic review, 25 studies and 790 patients with fractures of the femur, tibia and humerus were included, that met the inclusion and exclusion criteria. The mean age was 37.8 years, the time for union was 26 weeks, and 33 nonunions were observed. This study demonstrates satisfactory healing and alignment for treating tibial, femoral and humeral shaft fractures using this device. The main advantages of the expandable nail are minimal exposure to radiation and shorter operating time due to the lack of transverse locking.

The effect of different implant macrogeometry varying in shape along with the biomechanical effect of reduced buccal cortical bone thickness has not been studied and compared in the literature. The purpose of this finite element analysis (FEA) is to understand the stress distribution on the surrounding cortical bone for implants specially designed for use in anterior maxillary region and compare them with the conventional tapered (CT) implants. Also to assess the advantage of these implants in compromised buccal bone conditions. Two 3D FEA bone block in the maxillary anterior region were meshed with D3 type of bone. One block with uniform cortical bone thickness all around whereas other with reduced buccal cortical bone. Three different implant, inverted body shift (INB) (4.5*3.8*13), reverse neck collar (4.5*4.2*13) and CT implant (4.5*13). Each design was meshed into the different bone blocks creating total of six meshed models. An oblique load of 178 N from palatal side in the buccopalatal direction was applied. INB implant showed the best performance in terms of minimum stress concentration on the surrounding buccal bone specially in the reduced buccal cortical plate situation. The CT implant showed highest percentage increase in stress concentration on reducing buccal plate thickness. The new implant designs specially designed for maxillary anterior region where sufficient buccal bone is often lacking proved to be advantageous in such conditions due to the possibility of additional bone formation around the implant. With its high stability it should be preferred for use in compromised conditions.

The present study aimed to evaluate degree of functional and physiological integration of dental implant used for implant retained overdenture and comparing these adaptive change with conventional complete denture in edentulous participants. The psychophysical method evaluated active tactile sensibility (ATS) threshold of sensory receptors of oral cavity and neurophysiological method assessed neurological changes with help of functional magnetic resonance imaging (fMRI) during mastication in participants of both the groups. Mann-Whitney U test was done to compare ATS threshold and activity of sensory cortex in fMRI before and after implant installation in completely edentulous participants. Statistical result showed significant increase (P < 0.001) in activation of sensory cortex, motor cortex, prefrontal cortex, temporal lobe in participants after wearing implant retained overdenture compared with complete denture. For 200, 100, and 80 μm articulating papers non-significant change found between two test groups. The 40 and 12 μm articulating papers showed statistically significant change in ATS threshold (P < 0.05) between two test groups in 12-14 weeks. ATS threshold decreased more in participants with Implant retained overdenture prosthesis as compared with conventional complete denture prosthesis. Most of the activation was seen in prefrontal cortex and bilateral somato-sensory cortex with implant retained prosthesis compared with conventional complete denture prosthesis.

Despite the favorable long-term outcomes reported with implants-prosthetic rehabilitations, biological and technical complications may be frequent. This review aimed to describe the different implant-supported hybrid prostheses, assessing the frameworks designs, materials, mechanical behavior, and prosthetic complications. A search was done using Medline/PubMed and Scopus databases from January 1985 to December 2022. The most relevant papers were selected for the review from the retrieved papers. Manual search for list of references was also added. Mechanical complications are not unique to metal-acrylic resin HPs and have been documented with other metal-based implant-supported reconstructions and zirconia frameworks. Prosthetic complications including ceramic veneer chipping and framework failures have been reported with ceramic veneered zirconia complete arch frameworks. The design, fabrication method, material and misfit of implant-supported frameworks significantly influence the rate of prosthetic complications associated with full-arch HPs.

Total hip arthroplasty (THA) is a widely performed procedure that significantly enhances quality of life for patients with hip joint issues. The introduction of ceramic components in hip replacements has improved wear resistance and biocompatibility, but ceramic liner dissociation, though rare, remains a serious complication often necessitating revision surgery. This review synthesizes research on the prevalence, causes, and management of ceramic liner dissociation in THA. Key factors contributing to dissociation include improper component placement, liner locking mechanism failure, and specific surgical techniques. Diagnosis is often subtle, requiring imaging for confirmation. Management strategies emphasize precise surgical technique, component fit, and careful handling during revision. The review highlights the importance of understanding biomechanical factors to reduce complication risks and optimize outcomes.

Nowadays, dental implants are one of the essential treatments for human beings to maintain their chewing function and aesthetics. But after surgery, the Young modulus promotes stress shielding and stress simulation at the bone-implant contact, thus decreasing the density of the bone and, due to bone resorption, the dental implant fails. In this article, a material property is determined using simulation in Ansys software and using Design of Experiments (DoE) Informed Deep Learning model, which is generated for minimum stress shielding. Ashby plot is used to determine the best possible dental implant material in which five materials are obtained. Titanium and ceramics are functional in medical fields, while steels are not functional due to biocompatibility issues. However, carbon fiber-reinforced polymer (CFRP) is biocompatible and excellent for dental implants, but needs manufacturing attention. Nickel alloys can also be used for dental implants, however, their biocompatibility and technical difficulties need to be studied.