Cement Penetration Research Articles

Comparison of different cementing techniques for cement penetration under tibial component in total knee arthroplasty: a retrospective observational study

PurposeThis study aimed to investigate the differences in cement penetration between cementing techniques in total knee arthroplasty (TKA).Materials and methodsWe retrospectively evaluated knee undergone TKA at our hospital for both preoperative and postoperative computed tomographic (CT) evaluations. Cementing was performed with hand mixing and hand packing (HM group) and with vacuum mixing and cement gun use (VM group). We measured the area under the tibial baseplate (sclerotic and nonsclerotic sides) and compared the mean and maximum depths of cement penetration at each area.ResultsOf the 44 knees evaluated, 20 and 24 knees were in the HM and VM groups, respectively. At the center of the sclerotic side, the mean penetration depths (2.0 ± 0.7 and 2.5 ± 0.7 mm, p = 0.02) and the maximum penetration depths (4.0 ± 0.9 and 5.0 ± 1.6 mm, p = 0.02) were significantly deeper in the VM group than in the HM group. The correlation between preoperative Hounsfield unit values and mean penetration were r = –0.617 (p < 0.01) and –0.373 (p = 0.01) in the HM and VM groups, respectively.ConclusionThe cementing technique of vacuum mixing and using a cement gun allowed for deeper cement penetration compared with the hand mixing and hand packing technique, even in bone sclerotic sites.

Ultrasonic activation of adhesive systems increases bond strength and intratubular penetration of resin cement in root dentin subjected to radiation therapy.

This study aimed to evaluate the effect of ultrasonic activation of etch-and-rinse and self-etch adhesive systems on the bond strength of resin cement to irradiated root dentin. Eighty human maxillary anterior teeth were distributed into 8 groups (n = 10), according to the type of adhesive system used (etch-and-rinse and self-etch), the ultrasonic activation of the adhesive systems, and the dentin condition (irradiated or non-irradiated - 70Gy). Endodontic treatment was performed followed by fiberglass post-space preparation. After fiberglass posts' luting, the roots were transversely sectioned on dentin discs and submitted to the push-out bond strength test (0.5mm/min). The fractured specimens were analyzed under a stereomicroscope and Scanning Electron Microscope (SEM) for failure mode classification. One of the dentin discs was analyzed under SEM to evaluate the characteristics of the adhesive interface. Irradiated specimens had lower bond strength than non-irradiated specimens (P < 0.0001). Ultrasonic activation of both adhesive systems increased the bond strength of the resin cement to irradiated dentin (P < 0.0001). Radiotherapy significantly affected the failure mode in the middle (P = 0.024) and apical thirds (P = 0.032) (adhesive failure). Non-irradiated specimens had a more homogeneous adhesive interface. When ultrasonically activated, both adhesive systems showed a greater number of resinous tags, regardless of the dentin condition. Ultrasonic activation of adhesive systems is a feasible strategy to enhance fiberglass posts retention in oncological patients.

Relationship between cement penetration and incidence of a radiolucent line around the tibia 2 years after total knee arthroplasty: A retrospective study

ObjectivesCement penetration (CP) plays a key role in implant stability for cemented total knee arthroplasty (TKA), and the radiolucent line (RLL) >2 ​mm is a preliminary sign for loosening of components. However, the direct relationship between CP and the frequency of RLL >2 ​mm is unclear, and the best cut-off value for CP to prevent RLL >2 ​mm also remains unclear. This study aimed to investigate this relationship between CP and RLL and to determine the clinical cut-off value for tibial CP in patients 2 years after TKA. MethodsThis retrospective study investigated 157 knees from 123 patients with osteoarthritis who underwent cemented TKA. The CP and RLL immediately after TKA and the RLL 2 years after TKA were measured for the medial, lateral, anterior, and posterior tibial baseplate zones. Receiver operating characteristic (ROC) curves were constructed to determine the best cut-off values for CP. ResultsRLL >2 ​mm was not observed just after TKA. An RLL >2 ​mm was observed in any tibial baseplate zone in 22 knees from 20 patients (RLL+ group) and was not observed in the remaining (RLL− group) 2 years after TKA. The mean CP for all zones was significantly higher in the RLL− group (2.5 ​± ​1.1 ​mm) than in the RLL+ group (1.7 ​± ​0.6 ​mm; P ​< ​0.001). An RLL >2 ​mm was seen in 21 knees in the medial zone, 9 knees in the lateral zone, 8 knees in the anterior zone, and 3 knees in the posterior zone. CP values with RLL >2 ​mm were significantly lower than those without the RLL at the medial, anterior, and posterior tibial baseplate zones. The best cut-off values from the ROC curve of CP in each zone were between 1.1 ​mm and 2.1 ​mm. ConclusionsThe depth of the CP directly affects the incidence of an RLL >2 ​mm. The best cut-off value for tibial CP to prevent an RLL >2 ​mm is 2.1 ​mm.

Pulsed lavage is associated with better quality of bone-cement-implant interface in knee arthroplasties (TKA/UKA) compared to syringe lavage in vitro; however, clinical data are missing: A systematic review.

The purpose of this systematic review is to analyse the available literature to ascertain the optimal method of bone preparation to improve the quality of bone-cement-implant interface with either pulsed lavage or syringe lavage in both total knee arthroplasty (TKA) and unicompartmental knee arthroplasty (UKA). A comprehensive search was conducted across MEDLINE, Scopus and Embase databases until July 2023. Both inclusion and exclusion criteria were clearly stated and used to identify all the published studies. Subsequent screening throughout the title, abstract and full text was made, followed by complete critical appraisal and data extraction. This sequential process was performed by two reviewers independently and summarised following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines). A quality assessment of the systematic review was performed according to the Quality Appraisal for Cadaveric Studies scale (QUACS), reaching a quality level ranging from 69% to 85%. A total of 10 articles, out of 47, nine biomechanical cadaveric studies and one human clinical study were analysed. A total of 196 UKA tibial components, 74 patellar components, 36 TKA tibial components and 24 UKA femoral components were retrieved, and a high level of heterogeneity resulted overall. The pulsed lavage group showed better cement penetration and higher pull-out force than the syringe lavage group; a higher interface temperature was also found in the pulsed lavage group. No differences were found regarding tension ligament forces between the groups. Our systematic review suggests that pulsed lavage is superior to syringe lavage in terms of the quality of bone-cement-implant interface in knee arthroplasties (TKA/UKA). However, translation of these results from cadaveric studies to individual clinical settings may be hazardous; therefore, clinical in vivo prospective studies are highly needed. PROSPERO CRD number CRD42023432399. Level III.

Cementing techniques for total knee arthroplasty in Norwegian hospitals; a questionnaire-based study

BackgroundCementing technique in total knee arthroplasty (TKA) may influence implant survival. There is limited knowledge about the results with clinically used techniques.The aim of this study was to investigate cementing techniques for TKA in Norwegian hospitals, to compare widely used techniques to recommendations from the literature, and to investigate variation within hospitals.MethodsA questionnaire requesting information about cementing techniques were distributed to all Norwegian orthopedic surgeons performing TKAs regularly in 2020. Data was analyzed using descriptive statistical methods.ResultsWe acquired 121 responses out of 257 surgeons. They were from 45 out of 56 hospitals, and at least half of the TKA surgeons from 20 hospitals, constituting 79 surgeons. All responders used pulsatile lavage. Cement application to both the tibial plateau and stem (full cementation) was practiced by 61%. Application of cement to both implant and bone was done by 70% of surgeons. Techniques to improve cement penetration were used by 86%. Only 35% of surgeons aimed to get a cement mantle thickness between 3–5 mm. Flexing the knee joint to remove excess cement was done by 82%. We found that in 55% of 20 hospitals the surgeons did not agree on the use of common guidelines in their ward.ConclusionsThe majority of the responders used recommended techniques from the literature when cementing TKA. At more than half of the eligible hospitals, surgeons disagreed about their hospitals’ use of common guidelines. Focusing on developing evidence-based guidelines would be beneficial for TKA-quality.

Total Knee Arthroplasty: The Impact of Tourniquet Usage on Cement Penetration, Operation Time, and Bleeding Control

Objective: The cementing technique employed in total knee arthroplasty (TKA) significantly influences the penetration of cement into the bone, ultimately affecting the stability of the joint. This study aimed to assess the impact of tourniquet usage on tibial cement penetration, operative time, bleeding, and functional outcomes following TKA. Materials and Methods: A retrospective evaluation was conducted on 103 patients who had undergone TKA and had a minimum follow-up period of 2 years. The patients were categorized into three groups: Group 1 utilized a tourniquet throughout the entire surgery, Group 2 released the tourniquet immediately after prosthesis implantation, just before cement hardening, and Group 3 did not employ a tourniquet at any stage of the procedure. Tibial cement penetration was assessed via X-ray examination, following the Knee Society Scoring System criteria. Operative time, bleeding levels, and Lysholm and Oxford scores were compared among the groups. Statistical analysis was performed using SPSS version 22.0 software. Results: In Group 1, bone penetration of cement was significantly higher than in both Group 2 and Group 3, except for zone 1 in the anterior-posterior (AP) view (p &lt; 0.017). Group 3 exhibited significantly less bleeding compared to the other groups (p &lt; 0.017). There was no significant difference in terms of bleeding between Group 1 and Group 2. The operation time was significantly shorter in Group 1 compared to the other groups (p &lt; 0.017). The mean cement penetration depth across all groups was measured at 2.44 ± 0.27 mm. Bleeding volume and operation time did not have a significant effect on mean cement penetration (p &gt; 0.05). Additionally, there were no significant differences observed between the groups in terms of the Lysholm and Oxford functional test results (p &gt; 0.017). Conclusions: The use of a tourniquet was found to increase cement penetration and reduce operation time; however, it did not have a significant impact on reducing bleeding. Based on our findings, we recommend considering a shorter tourniquet time and implementing effective bleeding control measures to mitigate potential complications associated with tourniquet usage.

Micromotion measurement at the interfaces of cemented tibial endoprosthetic replacements: A new standardized in vitro model using open-cell rigid foam.

Early aseptic loosening following primary total knee arthroplasty related to several factors might appear at the interface implant-cement or cement-bone. A standardized in vitro model might provide information on the relevance of single variable parameter of cementation including technique and cement respectively bone structure on fixation strength. Micromotion measurement using different directions of load should detect the primary stability of the interfaces. An open-cell rigid foam model was used for cementation of PFC-Sigma tibial trays with Palacos®. Pins were applied to the model for continuous non-destructive measurement. Relative micromotions for rotation, valgus-varus and extension flexion stress were detected at the interfaces as well as cement penetration was measured. The reproducibility of the measurement could be shown for all interfaces in extension-flexion movements. For rotation a negative trend was shown for the interface cement-prosthesis and cement-bone concerning varus-valgus stress reflecting varying surgical cementation technique. More micromotion related to extension-flexion force might reflect the design of the implant. Measurement of relative micromotion and cement distribution appear accurate to detect small differences of movement at different interfaces of cemented tibial implants and the results are reproducible for most parameter. An increased number of specimens should achieve statistical relevance for all measurements.

Consequences of using poly-ether-ether-ketone versus traditional implant on tibial cement penetration and short-term clinical outcomes during total knee arthroplasty: a randomized controlled trial

BackgroundThe use of poly-ether-ether-ketone (PEEK) prosthesis during total knee arthroplasty (TKA) is a relatively new concept. Several studies have suggested that the thickness of cement penetration during TKA may affect the stability of the implants. The present study aimed to compare the cement penetration and clinical performance between PEEK and traditional cobalt chromium molybdenum (CoCrMo) prosthesis during TKA.MethodsThis study was a randomized controlled trial with level I of evidence. A total of 48 patients were randomly assigned to either the PEEK group (n = 24) or the CoCrMo group (n = 24). Mean bone cement penetration under the tibial baseplate was assessed radiographically in four zones in the anteroposterior view and two zones in the lateral view, in accordance with the Knee Society Scoring System. Furthermore, parameters such as the Knee Society Score (KSS), visual analogue scale (VAS) scores, complications and survivorship at 1 year postoperatively were also compared.ResultsAccording to the results of this study, the mean bone cement penetration exhibited no significant difference between PEEK and CoCrMo groups (2.49 ± 0.61 mm vs. 2.53 ± 0.68 mm, p = 0.85). Additionally, there were no remarkable differences in the KSS clinical score, functional score, and VAS score between the two groups. Moreover, complications and survivorship were also statistically compared between the groups and presented no significant differences.ConclusionsBased on the current findings, it can be concluded that PEEK implant present similar bone cement penetration, short-term clinical outcomes, and survivorship with traditional CoCrMo implant in TKA without added complications.Trial registration Chinese Clinical Trial Registry (ChiCTR2100047563).

Efficacy of Riboflavin Activated by PDT, Sapindus macrossi when Used as Final Irrigant on Microleakage, Sealer Penetration, Extrusion Bond Strength, and Martens Hardness Sealed with Bioactive Cement

Aim To compare the effects of riboflavin photosensitizer (RFP) Sapindus Macrossi (SM) on extrusion bond strength (EBS), Marten's hardness (MH), microleakage, and sealer penetration of bioactive cement. Materials and Methods Inclusion/exclusion criteria selected samples. All samples were opened, and the working length was established using pro taper for canal completion and steady irrigation with 2.25% NaOCl. Four randomly chosen groups. EDTA, RFP final irrigant, SM, and saline were the groups. Obturated samples were vertically put in 1% methylene blue dye and cut in half lengthwise for a stereomicroscope. SEM investigated dentinal tubule SP. Mean, standard deviation, and one-way ANOVA measured microleakage, EBS, and MH. Results Final watering procedures did not affect samples. Final irrigant SM increased sealer penetration. Radicular dentin irrigated with 2.25% NaOCl+ SM had the highest EBS in the cervical region. Group 2: 2.25% NaOCl+ RFP had the lowest MH while Group 1: SM had the highest. Conclusion Sapindus mukorossi, often known as soapberry or reetha, could replace current watering methods when used with a bioactive sealant.

Analysis of the Curative Effect of Curved Angle Vertebroplasty in the Treatment of Osteoporotic Vertebral Compression Fracture.

To evaluate the clinical efficacy of Percutaneous curved vertebroplasty (PCVP) for osteoporotic vertebral compression fracture of the thoracolumbar spine. Retrospective analysis of 113 patients with osteoporotic vertebral compressive fractures (OVCFs) in our hospital from January 2017 to January 2020, a total of 120 diseased vertebrae, were divided into PCVP group (35 cases, 37 sections) and bilateral PVP(BVP) group (78 cases, 83 sections). To compare the distribution of baseline clinical data, pain relief (Visual Analog Scale, VAS), ODI (Oswestry Dability Index, ODI), operation time, intraoperative fluoroscopy, postoperative vertebral body re-fracture, and comparison of bone, and to compare the volume of cement penetration and the leakage rate of bone cement, etc. There was no significant difference in VAS and ODI before operation between the two groups (P > 0.05), and the VAS score and ODI after operation were significantly improved (P < 0.001). Compared with the bilateral PVP group, the operation time, the number of fluoroscopy, and the leakage rate of each layer of bone cement in the PCVP group were significantly reduced (P < 0.05); however, the amount of cement used in the two groups was similar (P > 0.05). There were no serious complications in both groups. In the bilateral PVP group, a total of seven patients had adjacent vertebral fractures or re-fractures of the original vertebral body. However, no patients in the PCVP group had re-fractures in any vertebral body segment. Both PCVP and bilateral PVP are safe and effective methods for the treatment of osteoporotic vertebral compression fractures, but PCVP has a short operation time, fewer fluoroscopy times, and a low bone cement leakage rate.

Is TKA femoral implant stability improved by pressure applied cement? a comparison of 2 cementing techniques

BackgroundThe majority of knee endoprostheses are cemented. In an earlier study the effects of different cementing techniques on cement penetration were evaluated using a Sawbone model. In this study we used a human cadaver model to study the effect of different cementing techniques on relative motion between the implant and the femoral shaft component under dynamic loading.MethodsTwo different cementing techniques were tested in a group of 15 pairs of human fresh frozen legs. In one group a conventional cementation technique was used and, in another group, cementation was done using a pressurizing technique. Under dynamic loading that simulated real life conditions relative motion at the bone-implant interface were studied at 20 degrees and 50 degrees flexion.ResultsIn both scenarios, the relative motion anterior was significantly increased by pressure application. Distally, it was the same with higher loads. No significant difference could be measured posteriorly at 20°. At 50° flexion, however, pressurization reduced the posterior relative motion significantly at each load level. ConclusionThe use of the pressurizer does not improve the overall fixation compared to an adequate manual cement application. The change depends on the loading, flexion angle and varies in its proportion in between the interface zones.

The Effect of Systolic Blood Pressure on Cement Penetration Depth in Primary Total Knee Arthroplasty

Background: Cement Penetration Depth (CPD) into bone is an important factor for successful Total Knee Arthroplasties (TKA). Our study investigated the effect of Systolic Blood Pressure (SBP) on average tibial, femoral and total CPD in primary TKA. Methods and Findings: In this retrospective cohort study, patients who had a primary TKA between November 2018 and February 2020 at four, academic medical centers were included. CPD was evaluated according to the Knee Society Radiographic Evaluation System on radiographs one month post-operatively. Two independent evaluators measured four zones of tibial penetration and three zones of femoral penetration and averaged their results. The measurements were combined to create an average tibial, average femoral and average total CPD. SBP was collected at the 3/4 time of surgery length- the estimated time of cementation. 1221 primary TKA cases were included in the study – 1128 in the tourniquet group and 93 in the tourniquet-less group. There were no significant differences between the age, sex, BMI, or LOS between the two cohorts. A multiple, multivariate analysis was performed. In the tourniquet-less group, SBP did not significantly affect average tibial CPD (p=0.98), average femoral CPD (p=0.45), or average total CPD (p=0.23). However, tourniquet use was found to significantly increase average femoral (p&lt;0.001) and total penetration (p=0.001). Conclusion: SBP did not significantly affect tibial, femoral, or total CPD in patients undergoing tourniquet-less, primary TKA. However, the use of a tourniquet significantly aids in average femoral and total CPD. The clinical significance of this difference needs further investigation.

Evaluating the Performance of Aluminum Oxide Nanoparticle-Modified Asphalt Binder and Modelling the Viscoelastic Properties by Using Artificial Neural Networks and Support Vector Machines

The effect of aluminum oxide nanoparticles (Al2O3) on the 60/70 penetration of asphalt cement (AC) was investigated in terms of the physical and rheological characteristics by using the Superpave testing procedures. Al2O3 at 3, 5, and 7% concentrations were blended with 60/70 penetration of grade AC. Conventional testing procedures were adopted regarding the physical characteristics, while dynamic shear rheometer (DSR) testing procedures were conducted to evaluate the high and low temperature failure parameters. In addition, heuristic modelling techniques, artificial neural networks (ANN), and support vector machines (SVM) were employed to predict the performance characteristics of AC by using the mechanical testing conditions. The frequency sweep test and multiple stress creep recovery (MSCR) test results revealed that the optimum composition of Al2O3 was at 5% concentration considering the high temperature performance characteristics since further addition of the Al2O3 resulted in degradation in the enhanced properties due to agglomeration of the nanoparticles in the blend. On the contrary, Al2O3 5% demonstrated the lowest viscoelastic behavior at intermediate temperatures. The higher complex modulus ( G ∗ ) and lower phase angle ( δ ) parameters indicated that the increase in stiffness due to the modification process was at the cost of losing elastic properties against fatigue cracking. Moreover, based on the statistical performance indicator, coefficient of determination (R2), it was observed that the ANN models for predicting G ∗ and δ achieved a prediction accuracy of 0.989 and 0.911 while SVM models were able to achieve 0.984 and 0.929, respectively, considering the training datasets. On the other hand, it was noted that SVM models outperformed the ANN models in terms of a smaller gap between the results obtained from the training and testing datasets. The difference between the training and testing datasets for G ∗ and δ parameters for the SVM models were 3.2% and 6.8% while for the ANN models, the differences were 11.6% and 9.5%, respectively, indicating that the ANN models were more prone to the overfitting phenomenon.

Cementation in total hip arthroplasty: history, principles, and technique.

Total hip arthroplasty (THA) is a remarkably successful operation that has grown rapidly its utilization. Early modern THA constructs as developed by Sir John Charnley featured cemented femoral stems and acetabular components. The technique of cementing components for THA has evolved over time. Modern acetabular preparation requires exposure of the subchondral bone with appropriate cement penetration into the trabecular bone, whereas femoral preparation requires cleaning of the canal, cement restrictor placement, retrograde filling, and pressurization of the cement. When used appropriately, these techniques result in excellent long-term survivorship of implants and are also widely considered to be the ideal method of fixation for hip fractures. The purpose of this article to review the history, properties, techniques, and outcomes of bone cement utilization in THA.

Pressurized carbon dioxide lavage reduces the incidence of a radiolucent line around the tibial component two years after total knee arthroplasty

IntroductionIn cemented total knee arthroplasty (TKA), pressurized carbon dioxide (CO2) lavage prior to cement fixation can eliminate debris at the bone-cement interface and is considered effective for increasing cement penetration and preventing aseptic loosening. Regarding the risk of a preliminary diagnosis of implant loosening, a radiolucent line (RLL) is a valuable sign. The purpose of this study was to compare the incidence of a tibial RLL at 2 years after TKA with and without pressurized CO2 lavage.MethodsThis is a retrospective study. One hundred knees from 98 patients were enrolled in this study. TKA was performed without pressurized CO2 lavage (CO2− group) for the first 47 knees, and with pressurized CO2 lavage (CO2+ group) for the next 53 knees. The depth of cement penetration was measured just after surgery, and the incidence of tibial RLL > 2 mm at 2 years after TKA was determined.ResultsSignificant differences between groups were not seen regarding pre- and postoperative clinical factors. The depth of cement penetration in each area was significantly higher in the CO2+ group. The frequency of knees with RLL > 2 mm was significantly lower in the CO2+ group than in the CO2− group (p < 0.001).ConclusionsPressurized CO2 lavage improved cement penetration and decreased the incidence of tibial RLL > 2 mm at 2 years after TKA.

The Effect of Working Time and Application Technique on Cement Penetration into a Tibial Model

BackgroundAseptic loosening of the cemented tibial component is a source of failure in total knee arthroplasty. This study examined common techniques for cement application by quantifying depth and volume of penetration into tibia models. Material and methodsThirty-six composite tibia models were cemented with a tibial component using 3 application techniques (gun, osteotome, and layered) with either early or late cement working time. Computed tomography and 3D-modeling were used to quantify volume and depth of penetration. Statistical analysis was conducted with analysis of variance with Bonferroni correction and Student’s t-test. ResultsNo difference was found in overall volume of penetration between early and late cement application (P = .16). Beneath the baseplate, the layered technique had significantly less penetration and averaged less than 3 mm with early and late cement. The gun technique had the greatest depth of penetration with early cement and averaged greater than 3 mm in all zones regardless of cement working time. The osteotome technique achieved significantly greater depth of penetration around the keel with early and late cement, P < .01. ConclusionsUsing a cement gun ensures adequate penetration beneath the baseplate regardless of cement working time while the osteotome technique is effective to increase penetration around the implant keel. According to our study, applying cement early in its working time may not increase volume of penetration. This study raises concern regarding adequate cement penetration using the layered technique for cementing the tibial component in total knee arthroplasty, and future research is warranted.

The addition of a flange does not improve the pressure generated during cemented acetabular cup implantation.

Flanged acetabular cups were developed with the rationale that, at insertion, they would increase the pressure of the cement and improve penetration of cement into the acetabular bone. Various studies have been inconclusive regarding their effectiveness. In this work, we aimed to eliminate all confounding factors and measure the pressures generated during acetabular pressurization and cup implantation using a simplified steel acetabulum, high precision pressure transducers, proper surgical techniques and two acetabular cups, identical apart from the addition of a flange to one. It was found that the flanged acetabular component did not significantly increase the pressure in the acetabulum and in some cases reduced the pressures generated when compared to an unflanged cup. The addition of a flange did not reduce the pressure differential between the pole and the rim of the acetabulum, nor did it have a significant effect on pressure lost over the cup implantation period. It was concluded that flanged acetabular cups provide no significant improvement in the pressures generated in the acetabulum during acetabular cup implantation. It is hypothesized that the flange may be seen as a design feature intended to slow the insertion of the cup into the cement, thus requiring the surgeon to apply a larger load in order to correctly position the acetabular cup; in this way larger pressure will be generated.

Using suction in back-bleeding conditions increases cement penetration without the need for a tourniquet

BackgroundThe majority of total knee arthroplasties are performed with a tourniquet as it is perceived this gives rise to superior cement fixation. Tourniquets, however, have been associated with increased pain, post-operative swelling, and reduced knee range of movement which can all detrimentally impact patient recovery. This laboratory-based study aimed to assess if it is possible to achieve equivalent (or even enhanced) cementation without a tourniquet using a novel suction device. MethodsCement penetration was compared between conditions simulating bone with back-bleeding with and without the use of suction in open-cell rigid foam tibia models and porcine specimens. Suction was applied via a urinary catheter inserted into the tibial recess created for the implant's stem. Cement penetration depth was measured from micro-CT scans. The pull-off strength of cemented tibial implant analogues in porcine specimens with and without suction was also assessed. ResultsSuction gave rise to a significant (p = 0.028) increase in cement penetration depth in both the rigid foam, 5.4 – 6.6 mm, and porcine specimens, 0.7 – 1.0 mm. A non-significant increase in implant pull-off strength was also observed. ConclusionSuction during cementation in a back-bleeding model resulted in significantly greater cement penetration depth. Using suction surgeons can avoid potential disadvantages of tourniquet use without compromising cementation.

Influence of Dentin Surface Roughness, Drying Time, and Primer Application on Self-adhesive Composite-Cement Bond Strength.

To investigate the effect of roughness and drying time of dentin as well as the number of coats of a self-adhesive composite-cement primer on the bond strength of self-adhesive composite cement. Sixty human teeth were prepared and assigned to 12 groups (n = 5), according to three experimental factors: 1) dentin surface roughness, rough or fine, as achieved by 250- and 600-grit silicon carbide papers, respectively; 2) dentin wetness based on air-drying time (5 or 10 s); and 3) the self-adhesive composite-cement primer applications (no-coat, 1-coat, and 2-coat). Composite resin blocks were made with hybrid composite resin (M1 GraceFil) and cemented with G-CEM ONE (both GC). Cement-dentin sticks (12) were prepared, and the microtensile bond strength (μTBS) test was performed. Failure modes were observed with a stereomicroscope (40X), and bonding interfaces were evaluated with confocal laser scanning microscopy (CLSM). Statistical analysis was performed using three-way ANOVA and Tukey's post-hoc comparisons test (α = 0.05). Dentin roughness (250-grit > 600-grit, p = 0.000), drying time (5-s drying > 10-s drying, p = 0.000), and primer application (no-coat < 1-coat = 2-coat, p = 0.000) had significant effects on bond strength. These factors also showed significant interactions with each other (p = 0.003). The highest μTBS (31.8 ± 3.1 MPa) was observed in the 1-coat/fine roughness/10-s drying group and the lowest μTBS (13.4 ± 2.7 MPa) in the no-coat/coarse roughness/5-s drying group. CLSM showed higher penetration of cement in the primer-coated groups compared to that in the no-coat groups. Bond strength between the self-adhesive composite cement and dentin was higher in the fine-roughness dentin group than in the coarse-roughness dentin group, and in the 5-s drying group compared to the 10-s drying group. Applying a primer to dentin improved bond strength of the self-adhesive composite cement.

Does tibial design modification improve implant stability for total knee arthroplasty? An experimental cadaver study.

AimsOne of the main causes of tibial revision surgery for total knee arthroplasty is aseptic loosening. Therefore, stable fixation between the tibial component and the cement, and between the tibial component and the bone, is essential. A factor that could influence the implant stability is the implant design, with its different variations. In an existing implant system, the tibial component was modified by adding cement pockets. The aim of this experimental in vitro study was to investigate whether additional cement pockets on the underside of the tibial component could improve implant stability. The relative motion between implant and bone, the maximum pull-out force, the tibial cement mantle, and a possible path from the bone marrow to the metal-cement interface were determined.MethodsA tibial component with (group S: Attune S+) and without (group A: Attune) additional cement pockets was implanted in 15 fresh-frozen human leg pairs. The relative motion was determined under dynamic loading (extension-flexion 20° to 50°, load-level 1,200 to 2,100 N) with subsequent determination of the maximum pull-out force. In addition, the cement mantle was analyzed radiologically for possible defects, the tibia base cement adhesion, and preoperative bone mineral density (BMD).ResultsThe BMD showed no statistically significant difference between both groups. Group A showed for all load levels significantly higher maximum relative motion compared to group S for 20° and 50° flexion. Group S improved the maximum failure load significantly compared to group A without additional cement pockets. Group S showed a significantly increased cement adhesion compared to group A. The cement penetration and cement mantle defect analysis showed no significant differences between both groups.ConclusionFrom a biomechanical point of view, the additional cement pockets of the component have improved the fixation performance of the implant.Cite this article: Bone Joint Res 2022;11(4):229–238.