The effect of a 2-mm inter-implant distance on esthetic outcomes in immediately non-occlusally loaded platform shifted implants in healed ridges: 12-month results of a randomized clinical trial

BACKGROUND

Three millimeter is considered as the minimum distance to obtain soft and bone tissue stability in case of adjacent implants. The possibility to preserve peri-implant bone level using a platform switching connection has questioned this concept.

PURPOSE

The study evaluates soft tissue maintenance and marginal bone stability around implants, placed at 2 or 3 mm of distance.

MATERIALS AND METHODS

Thirty patients received two immediately loaded implants either at 2-mm (test) or at 3-mm (control) of distance in the premolar area. Soft tissue esthetics (papilla height and fill, keratinized tissue, recession) and radiographic peri-implant bone level changes were measured at 3, 6, and 12 months.

RESULTS

No significant differences between the two groups were detected neither for all soft tissue esthetic outcomes nor for bone level modifications up to 12 months.

CONCLUSION

The results suggested that up to 12 months post-loading, both 2- and 3-mm inter-distance platform-switched implants in healed site, supported adequate esthetic outcomes and peri-implant bone stability.

Implant Soft-Tissue Attachment Using 3D Oral Mucosal Models-A Pilot Study

PURPOSE

The aim of this study was to investigate soft-tissue attachment to different metal, ceramic, and polymer implant surfaces using an inflamed, three-dimensional (3D), tissue-engineered, human oral mucosal model, as well as multiple-endpoint qualitative and quantitative biological approaches.

METHODS

Normal human oral fibroblasts, OKF6/TERT-2 keratinocytes and THP-1 monocytes were cultured, and full-thickness, 3D oral mucosal models were engineered inside tissue culture inserts. Sand-blasted and acid-etched (SLA) and machined (M) titanium-zirconium alloy (TiZr; commercially known as Roxolid; Institut Straumann AG, Switzerland), ceramic (ZrO2), and polyether ether ketone (PEEK) rods (Ø 4 mm × 8 mm) were inserted into the center of tissue-engineered oral mucosa following a Ø 4mm punch biopsy. Inflammation was simulated with addition of the lipopolysaccharide (LPS) of Escherichia coli (E. coli) and tumor necrosis factor (TNF)-alpha to the culture medium. Implant soft-tissue attachment was assessed using histology, an implant pull-test with PrestoBlue assay, and scanning electron microscopy (SEM).

RESULTS

Inflamed, full-thickness, 3D human oral mucosal models with inserted implants were successfully engineered and histologically characterized. The implant pull-test with PrestoBlue assay showed higher viability of the tissue that remained attached to the TiZr-SLA surface compared to the other test groups. This difference was statistically significant (p < 0.05). SEM analysis showed evidence of epithelial cell attachment on different implant surfaces.

CONCLUSIONS

The inflamed, 3D, oral mucosal model has the potential to be used as a suitable in vitro test system for visualization and quantification of implant soft-tissue attachment. The results of our study indicate greater soft tissue attachment to TiZr-SLA compared to TiZr-M, ceramic, and PEEK surfaces.

The evolution of breast prostheses

Every year approximately 1.5 million prostheses are implanted worldwide for breast augmentation and reconstructive indications. The modern breast implant as we know was released to the open market in 1963. It has gone through intense phases of development which have improved the initially primitive and limited devices to current-day devices, which exhibit a tremendous range of surface textures, sizes, gel consistencies, and anatomical shapes. This article explores the evolution of breast implants providing historical facts and technical details.

Do radiolucent lines and stress shielding of the humeral shaft really matter in shoulder arthroplasty?

The purpose of this study is to evaluate at a mid-term follow up, the radiological survival of an uncemented humeral stem in shoulder arthroplasty. One hundred and twenty-six replacements including hemi (HA), total (TSA) and reverse (RSA) implanted from 1999 to 2008 were reviewed at a mean follow up of 7.2 years (48-144 months). The same uncemented triconical stem (SMR, Lima Corporate) was implanted. There were: 23 HSA, 43 TSA, 60 RSA. An independent observer evaluated all the patients with Constant Score. A radiologic analysis by an expert radiologist and an orthopaedic surgeon was performed: humeral component-bone interface was divided in seven zones. They judged a mobilisation if a migration or tilt of the humeral implant or if≥ 2 mm radiolucent line in at least three zones was present. Chi-squared test, Fisher test and analysis of variance were performed and a p<0.05 was considered statistically significant. No major radiological signs of loosening and no tilt or migration of the humeral component were found. Only 23 (18.2%) patients had no RL around the humeral implant. In the remaining 103 (81.7%) implants: 96 (76.1%) presented RL less than 2 mm, particularly 75 (59.5%) in less than 3 zones and 21 (16.6%) in more than 3 zones. Of the remaining 7 (5.5%) implants the presence of RL of 2 mm or greater in only one zone was seen. Apart from sepsis no revision was performed for humeral component loosening. Although a high rate of RL, uncemented humeral stem has an excellent survivorship at a mid-term follow up. Relationship between presence, position and depth of RL and internal stress shielding is commonly observed but does not appear to compromise quality of fixation or clinical outcomes in shoulder arthroplasty.

Novel in vivo mouse model of shoulder implant infection

BACKGROUND

Animal models are used to guide management of periprosthetic implant infections. No adequate model exists for periprosthetic shoulder infections, and clinicians thus have no preclinical tools to assess potential therapeutics. We hypothesize that it is possible to establish a mouse model of shoulder implant infection (SII) that allows noninvasive, longitudinal tracking of biofilm and host response through in vivo optical imaging. The model may then be employed to validate a targeting probe (1D9-680) with clinical translation potential for diagnosing infection and image-guided débridement.

METHODS

A surgical implant was press-fit into the proximal humerus of c57BL/6J mice and inoculated with 2 μL of 1 × 103 (e3), or 1 × 104 (e4), colony-forming units (CFUs) of bioluminescent Staphylococcus aureus Xen-36. The control group received 2 μL sterile saline. Bacterial activity was monitored in vivo over 42 days, directly (bioluminescence) and indirectly (targeting probe). Weekly radiographs assessed implant loosening. CFU harvests, confocal microscopy, and histology were performed.

RESULTS

Both inoculated groups established chronic infections. CFUs on postoperative day (POD) 42 were increased in the infected groups compared with the sterile group (P < .001). By POD 14, osteolysis was visualized in both infected groups. The e4 group developed catastrophic bone destruction by POD 42. The e3 group maintained a congruent shoulder joint. Targeting probes helped to visualize low-grade infections via fluorescence.

DISCUSSION

Given bone destruction in the e4 group, a longitudinal, noninvasive mouse model of SII and chronic osteolysis was produced using e3 of S aureus Xen-36, mimicking clinical presentations of chronic SII.

CONCLUSION

The development of this model provides a foundation to study new therapeutics, interventions, and host modifications.

Breast Implant-Associated Anaplastic Large Cell Lymphoma Following Gender Reassignment Surgery: A Review of Presentation, Management, and Outcomes in the Transgender Patient Population

Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is a rare peripheral T-cell lymphoma with approximately 650-700 reported cases worldwide. The incidence, however, is increasing as more practitioners become aware of the diagnosis, and recent studies show that early diagnosis and treatment is critical to improve prognosis. There have been four cases of BIA-ALCL in total reported in the transgender population in the literature. These reported cases were reviewed in detail to determine presentation and management of BIA-ALCL in transgender patients compared to the larger population of BIA-ALCL patients. This review highlights BIA-ALCL in transgender women, a population that is often excluded from breast screening and follow-up. Transgender women may not routinely go through the same post-operative follow-up protocols as patients with breast implants for breast cancer reconstruction and can thus be at risk for delayed recognition and diagnosis. BIA-ALCL is a rare complication of breast implantation, and it is important to counsel all patients undergoing implant placement, including transgender women, on its risk.

Implantable self-aligning fiber-optic optomechanical devices for in vivo intraocular pressure-sensing in artificial cornea

Artificial cornea is an effective treatment of corneal blindness. Yet, intraocular pressure (IOP) measurements for glaucoma monitoring remain an urgent unmet need. Here, we present the integration of a fiber-optic Fabry-Perot pressure sensor with an FDA-approved keratoprosthesis for real-time IOP measurements using a novel strategy based on optical-path self-alignment with micromagnets. Additionally, an alternative noncontact sensor-interrogation approach is demonstrated using a bench-top optical coherence tomography system. We show stable pressure readings with low baseline drift (<2.8 mm Hg) for >4.5 years in vitro and efficacy in IOP interrogation in vivo using fiber-optic self-alignment, with good initial agreement with the actual IOP. Subsequently, IOP drift in vivo was due to retroprosthetic membrane (RPM) formation on the sensor secondary to surgical inflammation (more severe in the current pro-fibrotic rabbit model). This study paves the way for clinical adaptation of optical pressure sensors with ocular implants, highlighting the importance of controlling RPM in clinical adaptation.

Intraoperative Intercostal Nerve Block for Postoperative Pain Control in Pre-Pectoral versus Subpectoral Direct-to-Implant Breast Reconstruction: A Retrospective Study

Background and Objectives: Patients undergoing mastectomy and implant-based breast reconstruction have significant acute postsurgical pain. The purpose of this study was to examine the efficacy of intercostal nerve blocks (ICNBs) for reducing pain after direct-to-implant (DTI) breast reconstruction. Materials and Methods: Between January 2019 and March 2020, patients who underwent immediate DTI breast reconstruction were included in this study. The patients were divided into the ICNB or control group. In the ICNB group, 4 cc of 0.2% ropivacaine was injected intraoperatively to the second, third, fourth, and fifth intercostal spaces just before implant insertion. The daily average and maximum visual analogue scale (VAS) scores were recorded by the patient from operative day to postoperative day (POD) seven. Pain scores were compared between the ICNB and control groups and analyzed according to the insertion plane of implants. Results: A total of 67 patients with a mean age of 47.9 years were included; 31 patients received ICNBs and 36 patients did not receive ICNBs. There were no complications related to ICNBs reported. The ICNB group showed a significantly lower median with an average VAS score on the operative day (4 versus 6, p = 0.047), lower maximum VAS scores on the operative day (5 versus 7.5, p = 0.030), and POD 1 (4 versus 6, p = 0.030) as compared with the control group. Among patients who underwent subpectoral reconstruction, the ICNB group showed a significantly lower median with an average VAS score on the operative day (4 versus 7, p = 0.005), lower maximum VAS scores on the operative day (4.5 versus 8, p = 0.004), and POD 1 (4 versus 6, p = 0.009), whereas no significant differences were observed among those who underwent pre-pectoral reconstruction. Conclusions: Intraoperative ICNBs can effectively reduce immediate postoperative pain in subpectoral DTI breast reconstruction; however, it may not be effective in pre-pectoral DTI reconstruction.

Time-Transient Effects of Silver and Copper in the Porous Titanium Dioxide Layer on Antibacterial Properties

Recently, silver (Ag) and copper (Cu) have been incorporated into a titanium (Ti) surface to realize their antibacterial property. This study investigated both the durability of the antibacterial effect and the surface change of the Ag- and Cu-incorporated porous titanium dioxide (TiO2) layer. Ag- and Cu-incorporated TiO2 layers were formed by micro-arc oxidation (MAO) treatment using the electrolyte with Ag and Cu ions. Ag- and Cu-incorporated specimens were incubated in saline during a period of 0-28 days. The changes in both the concentrations and chemical states of the Ag and Cu were characterized using X-ray photoelectron spectroscopy (XPS). The durability of the antibacterial effects against Escherichia coli (E. coli) were evaluated by the international organization for standardization (ISO) method. As a result, the Ag- and Cu-incorporated porous TiO2 layers were formed on a Ti surface by MAO. The chemical state of Ag changed from Ag2O to metallic Ag, whilst that of Cu did not change by incubation in saline for up to 28 days. Cu existed as a stable Cu2O compound in the TiO2 layer during the 28 days of incubation in saline. The concentrations of Ag and Cu were dramatically decreased by incubation for up to 7 days, and remained a slight amount until 28 days. The antibacterial effect of Ag-incorporated specimens diminished, and that of Cu was maintained even after incubation in saline. Our study suggests the importance of the time-transient effects of Ag and Cu on develop their antibacterial effects.

Effects of UV Treatment on Ceria-Stabilized Zirconia/Alumina Nanocomposite (NANOZR)

Nanostructured zirconia/alumina composite (NANOZR) has been explored as a suitable material for fabricating implants for patients with metal allergy. In this study, we examined the effect of UV treatment on the NANOZR surface. The experimental group was UV-treated NANOZR and the control group was untreated NANOZR. Observation of the surface of the UV-treated materials revealed no mechanical or structural change; however, the carbon content on the material surface was reduced, and the material surface displayed superhydrophilicity. Further, the effects of the UV-induced superhydrophilic properties of NANOZR plates on the adhesion behavior of various cells were investigated. Treatment of the NANOZR surface was found to facilitate protein adsorption onto it. An in vitro evaluation using rat bone marrow cells, human vascular endothelial cells, and rat periodontal ligament cells revealed high levels of adhesion in the experimental group. In addition, it was clarified that the NANOZR surface forms active oxygen and suppresses the generation of oxidative stress. Overall, the study results suggested that UV-treated NANOZR is useful as a new ceramic implant material.

Biomimetic in vitro test system for evaluation of dental implant materials

OBJECTIVES

Before application in dental practice, novel dental materials are tested in vitro and in vivo to ensure safety and functionality. However, transferability between preclinical and clinical results is often limited. To increase the predictive power of preclinical testing, a biomimetic in vitro test system that mimics the wound niche after implantation was developed.

METHODS

First, predetermined implant materials were treated with human blood plasma, M2 macrophages and bone marrow stromal stem cells. Thereby, the three-dimensional wound niche was simulated. Samples were cultured for 28 days, and subsequently analyzed for metabolic activity and biomineralization. Second test level involved a cell-infiltrated bone substitute material for an osseointegration assay to measure mechanical bonding between dental material and bone. Standard and novel dental materials validated the developed test approach.

RESULTS

The developed test system for dental implant materials allowed quantification of biomineralization on implant surface and assessment of the functional stability of mineralized biomaterial-tissue interface. Human blood plasma, M2 macrophages and bone marrow stromal stem cells proved to be crucial components for predictive assessment of implant materials in vitro. Biocompatibility was demonstrated for all tested materials, whereas the degree of deposited mineralized extracellular matrix and mechanical stability differed between the tested materials. Highest amount of functional biomineralization was determined to be on carbon-coated implant surface.

SIGNIFICANCE

As an ethical alternative to animal testing, the established in vitro dental test system provides an economic and mid-throughput evaluation of novel dental implant materials or modifications thereof, by applying two successive readout levels: biomineralization and osseointegration.

Novel Coatings to Minimize Bacterial Adhesion and Promote Osteoblast Activity for Titanium Implants

Titanium nitride (TiN) and silicon carbide (SiC) adhesion properties to biofilm and the proliferation of human osteoblasts were studied. Quaternized titanium nitride (QTiN) was produced by converting the surface nitrogen on TiN to a positive charge through a quaternization process to further improve the antibacterial efficiency. The SiC required a nitridation within the plasma chamber of the surface layer before quaternization could be carried out to produce quaternized SiC (QSiC). The antimicrobial activity was evaluated on the reference strains of Porphyromonas gingivalis for 4 h by fluorescence microscopy using a live/dead viability kit. All the coatings exhibited a lower biofilm coverage compared to the uncoated samples (Ti—85.2%; TiN—24.22%; QTiN—11.4%; SiC—9.1%; QSiC—9.74%). Scanning Electron Microscope (SEM) images confirmed the reduction in P. gingivalis bacteria on the SiC and TiN-coated groups. After 24 h of osteoblast cultivation on the samples, the cell adhesion was observed on all the coated and uncoated groups. Fluorescence images demonstrated that the osteoblast cells adhered and proliferated on the surfaces. TiN and SiC coatings can inhibit the attachment of Porphyromonas gingivalis and promote osteoblast adhesion on the titanium used for implants. These coatings may possess the ability to prevent the development of peri-implantitis and stimulate osteointegration.

Patients with psychiatric illness report worse patient-reported outcomes and receive lower rates of autologous breast reconstruction

Psychiatric well-being impacts on general satisfaction and quality of life. This study explored how the presence of psychiatric diagnoses affects patient-reported outcomes in breast reconstruction and on selection of reconstructive modality. Patients who received breast reconstruction at a tertiary hospital between 2013 and 2018 and completed the BREAST-Q survey were included. BREAST-Q module scores were compared between patients who had a psychiatric diagnosis at presentation and the remaining cohort using t tests. General linear models (GLMs) were used to control for confounding factors. A chi-squared test was used to assess the effect on reconstructive modality, and binary logistic regression was used to control for confounding factors. Of the 471 patients included, 93 (19.7%) had at least one psychiatric diagnosis. Cohorts did not differ significantly by age, BMI, race, ASA classification, or insurance status. Patients with a psychiatric diagnosis experienced a decrease in BREAST-Q scores for the Psychosocial Wellbeing (B = 9.16, P = .001) and Sexual Wellbeing (B = 9.29, P = .025) modules. On binary logistic regression, patients with a psychiatric diagnosis were less likely to receive autologous reconstruction compared with implant reconstruction (OR = 0.489, P = .010). The presence of psychiatric diagnoses is an independent predictor of decreased BREAST-Q. Furthermore, there is a significant disparity in modality of reconstruction given to patients with psychiatric diagnoses. Further study is needed to evaluate interventions to improve satisfaction among at-risk populations and evaluate the reason for low autologous reconstruction in this population.

Partial trapeziectomy and pyrocarbon interpositional arthroplasty for trapeziometacarpal osteoarthritis: minimum 8-year follow-up

We undertook a retrospective study to evaluate minimal 8-year outcomes of 46 trapeziometacarpal joints (46 patients) treated with pyrocarbon implant arthroplasty after partial trapeziectomy for trapeziometacarpal joint osteoarthritis in two different hand surgery units. The mean follow-up interval was 9.5 years (average 113 months with a range 97-144 months). The study showed that pyrocarbon interpositional arthroplasty provided pain relief and high patient satisfaction. All patients experienced a reduction in the DASH score, with an average change of 30 points. The visual analogue scale score, the Kapandji score, and key pinch also showed remarkable improvement. The PyroDisk implant exhibited good longevity, with good implant survival. A review of the literature revealed that the functional outcomes after implant surgery are not superior to more common techniques, such as trapeziectomy with or without ligamentoplasty. Therefore, this is a reliable surgery but may not have added benefits over simpler surgical treatments. This implant could have a role, perhaps in a select group of young patients, as a time-procuring procedure. Level of evidence: IV.

Characteristics of three different patellar implant designs in total knee arthroplasty

BACKGROUND

Despite debate over the role of patellar resurfacing in total knee arthroplasty, many surgeons feel it decreases re-operation rates and anterior pain, and an increasing number are adopting resurfacing. This study compares intra-operative characteristics of different patellar implants to assist surgeons in gaining better understanding of these implants.

METHODS

The three most commonly used patellar implants (inset, onlay round and onlay oval) were allocated randomly to 120 patients undergoing total knee arthroplasty. We compared the groups in terms of implant size, bone coverage, lateral underhang (uncovered lateral facet) and need for partial lateral facetectomy. We also compared the patient-reported outcome measures between the groups at 6 months post-operatively.

RESULTS

The inset, onlay round and onlay oval designs had bone coverage of 48.5%, 65.9% and 85.9%, respectively (P < 0.01). Similarly, the onlay-oval implant was found to have the smallest lateral underhang of all three designs (inset 11.6 mm; onlay round 6.9 mm, onlay oval 1.6 mm, P < 0.01). The onlay-oval design was the largest implant with a median size of 35 mm, compared to 23 mm for the inset and 32 mm for the onlay round (P < 0.01). In addition, patellae using onlay-oval implants required significantly fewer lateral facetectomies due to improved bone coverage (inset 95%; onlay round 87%; onlay oval 3%; P < 0.01). Finally, comparison of patient-reported outcome measures between the groups showed no difference at an early assessment of 6 months.

CONCLUSION

Onlay-oval design allows for the use of a larger implant, improving bone coverage and reducing the need for partial lateral facetectomy; however, early assessment of outcomes shows no difference between the three designs.

A Simple and Safe Approach for Maxillary Sinus Augmentation with the Advanced Surgical Guide

Objective: The development of digital dentistry has contributed to the astonishing advancement of implant dentistry. Furthermore, digital technology is expected to be applied extensively to sinus augmentation, which is an advanced technique for implant surgery. This study introduces a simple method for a safer and more precise lateral window opening for sinus augmentation using a navigation program. Methods: Five eligible patients with residual alveolar bone of 4 mm or less are presented, requiring lateral approach for sinus augmentation. Navigation system was opted for the sinus lift with simultaneous implant placement. Virtual planning started with establishing the adequate position of the lateral window based on the radiographic images and the scanned file of the dentition. The position of the window was indicated on the guide within the program. Afterwards, the virtually designed surgical guide was fabricated either with 3D printer or milling machine for the actual surgery. Results: All the patients who underwent surgery with the surgical guide showed no sign of clinical complications including pain, swelling, nausea, epistaxis, or early loss of the implants. Results of radiographic evaluation also showed adequate placement of the implants in a pre-planned position, and the sinus window was also formed in the desired location. Conclusion: Lateral window opening combined with digital navigation system is believed to be a promising technique for a more precise as well as safer sinus augmentation.

Implant-based immediate breast reconstruction: failure rate when radiating the tissue expander or the permanent implant-a meta-analysis

Background

Implant-based immediate approach remains to be a first line option for reconstruction of mastectomy defects. When combined with post-mastectomy radiation therapy (PMRT) two different schemas are possible: radiating the temporary tissue expander (TTE) or the permanent implant (PI). The present article intends to be the biggest cohort meta-analysis to the date comparing reconstructive failure (RF) rate in these two scenarios: PMRT to TE compared with PMRT to PI.

Methods

A systematic search of the literature was performed on PUBMED/MEDLINE. The following key words were chosen: Breast Reconstruction AND Implant based AND Immediate. The time limit applied was from January 2008 to January 2019. We selected ten articles (n=1,130) to perform a meta-analysis due to the similarity of their approaches. Secondly, we did a simple literature review in order to identify some variables possibly working as predicting factors for RF.

Results

Previous meta-analysis are analysed. Some variables possibly working as risk factors for RF are summarized. We performed a meta-analysis in two scenarios: a fixed-effect model and a random effect model. For the random effect model an OR of 1.85 was obtained (0.96, 3.57; P=0.067). A funnel plot is performed showing no publication bias exists.

Conclusions

There is a tendency towards a higher RF rate when the TTE is irradiated compared with the irradiation of the PI. Further studies trying to elucidate the influence of the suggested risk factors for RF have to be performed to stablish a consensus about the indications and contraindications of this reconstructive modality.

Multifunctional hydroxyapatite and hopeite coatings on SS254 by laser rapid manufacturing for improved osseointegration and antibacterial character: A comparative study

Orthopaedic metallic implant's long-term success strongly depends upon the two main factors: osseointegration and antibacterial character. Bioceramic (hydroxyapatite and hopeite) coatings have been proven effective for getting strong osseointegration and antibacterial character. However, deterioration of bioceramic coatings during the implantation period can adversely affect its overall biological performance. To conquer this issue, this research work recommends an innovative process route of laser rapid manufacturing for depositing bioceramic (hydroxyapatite and hopeite) coatings with metallurgical bonding. Microstructure, phase composition, antibacterial efficacy and bioactivity were evaluated using scanning electron microscopy, X-ray diffraction, fluorescence-activated cell sorting technique and simulated body fluid immersion test. The promising results obtained from these characterizations and testing establish the new process route laser rapid manufacturing as an effective alternative to deposit multifunctional bioceramic (hydroxyapatite and hopeite) coatings on metallic prosthetic-orthopaedic implants.

Laser-Based Ablation of Titanium-Graphite Composite for Dental Application

Biocompatible materials with excellent mechanical properties as well as sophisticated surface morphology and chemistry are required to satisfy the requirements of modern dental implantology. In the study described in this article, an industrial-grade fibre nanosecond laser working at 1064 nm wavelength was used to micromachine a new type of a biocompatible material, Ti-graphite composite prepared by vacuum low-temperature extrusion of hydrogenated-dehydrogenated (HDH) titanium powder mixed with graphite flakes. The effect of the total laser energy delivered to the material per area on the machined surface morphology, roughness, surface element composition and phases transformations was investigated and evaluated by means of scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), confocal laser-scanning microscopy (CLSM) and X-ray diffraction analysis (XRD). The findings illustrate that the amount of thermal energy put to the working material has a remarkable effect on the machined surface properties, which is discussed from the aspect of the contact properties of dental implants.

Summary of knee implant one, three, five, and 10-year revision risk reported by national and regional arthroplasty registries: a valuable source of evidence for clinical decision-making

Optimal implant selection is a major component of high-quality arthroplasty care, and revision risk is an important parameter characterizing knee arthroplasty implant clinical performance.

National and regional arthroplasty registries are essential sources of revision risk data, but these data are often difficult to find because they are buried within extensive annual reports. Summarizing total knee arthroplasty (TKA) implant revision risks as presented in registry reports can maximize the usefulness of registry data for orthopaedic surgeons.

The findings summarize the revision risk data found in national arthroplasty reports from the Australian, Danish, Finnish, and the England, Wales, Northern Ireland and the Isle of Man registries, and in regional arthroplasty reports from the Emilia-Romagna Region (Italty), and the Michigan Arthroplasty Registry Collaborative Quality Initiative (MARCQI) registries.

The six supplemental summary tables present revision risk data for TKA implants by cemented, uncemented, hybrid, and unreported fixation types. Additional summary tables are presented for revision risk of unicondylar (UKA) and patellofemoral joint (PFJ) revisions. Within TKA fixation categories, revision risks at 10 years ranged from 2.4% to 35.7% (cemented), 2.8% to 25.0% (uncemented), 2.0% to 9.2% (hybrid), and 0.0% to 39.7% (unreported). Unicondylar 10-year revision risk ranged from 4.9% to 17.2%. Patellofemoral joint 10-year revision risk ranged from 15.2% to 21.7%.

There is substantial variation in one, three, five, and 10-year revision risk across implants, which suggests surgeons should choose implants carefully.

Cite this article: EFORT Open Rev 2020;5:268-272. DOI: 10.1302/2058-5241.5.190053

Papillary endothelial hyperplasia (Masson's tumor) developed in the capsule of the implant in a breast cancer patient treated with mastectomy and radiation therapy

Papillary endothelial hyperplasia (PEH) is an uncommon benign vascular proliferation appearing in soft tissues in different body areas including the breast, which may be related to radiation therapy. A 48-year-old woman previously treated for breast cancer with mastectomy followed by radiation therapy and reconstruction with an implant presented with a newly developing mass in the implant capsule. Pathological diagnosis was PEH. Imaging features of this rare entity are described, and lesions included in differential diagnosis are discussed.

Multi-Axis Fatigue Experimentation System of Intramedullary Implants for Femur and Tibia

Current designs of leg-lengthening implants have faced serious failures due to inadequacies in the mechanical design. The failure typically is the result of fatigue induced by a combined loading condition with axial and shear components acting in the tubular body of the implant. One of the reasons leading to the failure is improper verification testing for the design of the fatigue limit. The current test standards for pre-clinical design phases of nail implants are relatively straightforward and widely accepted yet cannot produce the three-dimensional stress state representative of the anticipated operation in a patient during the consolidation phase. This work introduces a major improvement toward a method for verifying fatigue life of tubular as well as solid implants under combined torque, axial load, and bending. The report describes a new loading fixture, a calibration method, and compares the qualification results of finite element simulation analyses and experimental measurements during cyclic loading tests. The findings state that the fixture produces controlled multi-axial loadings to study varied osteotomy locations, quasi-static strength and fatigue of intramedullary implants at an intermediate, 2 Hz, cycle rate. © 2019 The Authors. Journal of Orthopaedic Research® published by Wiley Periodicals, Inc. on behalf of Orthopaedic Research Society. J Orthop Res 38:984-995, 2020.

Si-Fe-C-N Coatings for Biomedical Applications: A Combinatorial Approach

Ceramic coatings may prolong the lifetime of joint implants. Certain ions and wear debris may however lead to negative biological effects. SiN-based materials may substantially reduce these effects, but still need optimization for the application. In this study, a combinatorial deposition method enabled an efficient evaluation of a range of Si-Fe-C-N coating compositions on the same sample. The results revealed compositional gradients of Si (26.0-33.9 at.%), Fe (9.6-20.9 at.%), C (8.2-13.9 at.%) and N (39.7-47.2 at.%), and low oxygen contaminations (0.3-0.6 at.%). The mechanical properties varied with a hardness (H) ranging between 13.7-17.3 GPa and an indentation modulus (M) between 190-212 GPa. Both H and M correlated with the Si (H and M increased as Si increased) and Fe (H and M decreased as Fe increased) content. A slightly columnar morphology was observed in cross-sections, as well as a surface roughness in the nm range. A cell study revealed adhering pre-osteogenic MC3T3 cells, with a morphology similar to that of cells seeded on a tissue culture plastic control. The investigated coatings could be considered for further investigation due to the ability to tune their mechanical properties while maintaining a smooth surface, together with their promising in vitro cell response.

An In Vivo Study in Rat Femurs of Bioactive Silicate Coatings on Titanium Dental Implants

Silica-based ceramics have been proposed for coating purposes to enhance dental and orthopedic titanium (Ti) implant bioactivity. The aim of this study was to investigate the influence of sphene-based bioceramic (CaO.TiO₂.SiO₂) coatings on implant osseointegration in vivo. Sphene coatings were obtained from preceramic polymers and nano-sized active precursors and deposited by an automatic airbrush. Twenty customized Ti implants, ten sphene-coated and ten uncoated rough implants were implanted into the proximal femurs of ten Sprague-Dawley rats. Overall, cortical and cancellous bone-to-implant contact (BIC) were determined using micro-computed tomography (micro-CT) at 14 and 28 days. Moreover, peri-implant bone healing was histologically and histomorphometrically evaluated. The white blood cell count in the synovial fluid of the knee joints, if present, was also assessed. No difference in the BIC values was observed between the sphene-coated and uncoated implants, overall and in the two bone compartments (p > 0.05). Delamination of the coating occurred in three cases. Consistently with micro-CT data, the histological evaluation revealed no differences between the two groups. In addition, no synovial fluid could be collected on the test side, thus confirming sphene biocompatibility. In conclusion, sphene coating was found to be a suitable material for biomedical applications. Further studies are needed to improve coating adhesion to the implants.