Comparative analysis of the physical, chemical, and microbiological properties of Ti-6Al-4V disks produced by different methods and subjected to surface treatments.

STATEMENT OF PROBLEM: To improve the osseointegration of dental implants and reduce microbiological growth, different micro- and nanoscale surface topographies can be used. PURPOSE: The purpose of this in vitro study was to evaluate the influence of Ti-6Al-4V with 4 surfaces, machined (DU), machined+hydroxyapatite (DUHAp), machined+acid-alkali treatment (DUAA), and additive manufacturing (DMA), on the physical, chemical, and microbiological properties. MATERIAL AND METHODS: The topography of Ti-6Al-4V disks with the 4 surfaces was evaluated by scanning electron microscopy (SEM), the chemical composition by energy dispersive X-ray spectroscopy (EDS), and the crystalline structure by X-ray diffraction (XRD). Physical and chemical properties were analyzed by using wettability and surface free energy, roughness, and microbial adhesion against Staphylococcus aureus by colony forming units (CFU). One-way ANOVA analysis of variance and the Tukey multiple comparisons test were applied to evaluate the data, except CFU, which was submitted to the Kruskal-Wallis nonparametric test (α=.05). RESULTS: DU photomicrographs showed a topography characteristic of a polished machined surface, DUHAp and DUAA exhibited patterns corresponding to the surface modifications performed, and in DMA the presence of partially fused spherical particles was observed. The EDS identified chemical elements inherent in the Ti-6Al-4V, and the DUHAp and DUAA disks also had the ions from the treatments applied. XRD patterns revealed similarities between DU and DMA, as well as characteristic peaks of hydroxyapatite (HA) in the DUHAp disk and the DUAA. Compared with DU and DMA the DUHAp and DUAA groups showed hydrophilic behavior with smaller contact angles and higher surface free energy (P<.05). DMA showed a higher mean value of roughness, different from the others (P<.05), and a higher CFU for S. aureus (P=.006). CONCLUSIONS: DUHAp and DUAA showed similar behaviors regarding wettability, surface free energy, and bacterial adhesion. Among the untreated groups, DMA exhibited higher roughness, bacterial adhesion, and lower wettability and surface free energy.

Non-surgical treatment of mild to moderate peri-implantitis with an oscillating chitosan brush or a titanium curette-12-month follow-up of a multicenter randomized clinical trial.

OBJECTIVES: To study clinical and radiographic outcomes after non-surgical treatment of peri-implantitis using either an oscillating chitosan brush (OCB) or titanium curette (TC) and to observe changes in clinical signs of inflammation after repeated treatment. METHODS: Thirty-nine patients with dental implants (n = 39) presented with radiographic bone level (RBL) of 2-4 mm, bleeding index (BI) ≥ 2, and probing pocket depth (PPD) ≥ 4 mm were randomly assigned to mechanical debridement with OCB (test) or TC (control). Treatment was performed at baseline and repeated at 3, 6, and 9 months in cases with > 1 implant site with BI ≥ 1 and PPD≥4 mm. Blinded examiners recorded PPD, BI, pus, and plaque. The radiographic bone level change between baseline and 12 months was calculated. A multistate model was used to calculate transitions of BI. RESULTS: Thirty-one patients completed the study. Both groups exhibited a significant reduction in PPD, BI, and pus at 12 months compared to baseline. Radiographic analysis showed stable mean RBL in both groups at 12 months. There was no statistically significant difference in any of the parameters between the groups. CONCLUSIONS: Within the limitations of this 12-month multicenter randomized clinical trial, non-surgical treatment of peri-implantitis with OCB or TC showed no statistically significant differences between the groups. Clinical improvements and, in some cases, disease resolution, was observed in both groups. However, persistent inflammation was a common finding which further puts emphasis on the need for further treatment.

Multifunctional Au Modified Ti3C2-MXene for Photothermal/Enzyme Dynamic/Immune Synergistic Therapy.

Ti3C2-MXene-based composites provide multifunctional interfaces in diagnosis and treatment of tumors. Herein, we proposed a multifunctional nanoplatform based on Ti3C2-MXene-Au nanocomposites, which combines photothermal properties and peroxidase-like activity, accomplishing synergistic photothermal therapy (PTT) and enzyme dynamic therapy (EDT) accompanied by photoacoustic (PA) and thermal dual-mode imaging in vivo. Furthermore, PTT induces immunogenic cell death, and EDT promotes cell apoptosis, facilitating dendritic cell (DC) maturation and T cell infiltration into the tumor. On this basis, the antibody OX40 (αOX40) was utilized to further contribute immune therapy for reversing the immunosuppressive tumor microenvironment by activating CD4+ and CD8+ T cells. In summary, a triune of PTT/EDT/antitumor immune therapy is achieved by combining Ti3C2-MXene-Au nanocomposites and αOX40, which possesses several strong features of good biocompatibility, NIR-controlled targeting, significant cancer cell killing, and satisfactory biosafety in vitro and in vivo. Our work might highlight the promising application of MXene-based nanoplatforms for cancer therapy.

Efficacy of antibacterial agents combined with erbium laser and photodynamic therapy in reducing titanium biofilm vitality: an in vitro study.

BACKGROUND AND OBJECTIVE: The emergence of peri-implant diseases has prompted various methods for decontaminating the implant surface. This study compared the effectiveness of three different approaches, chlorhexidine digluconate (CHX) combined with erbium-doped yttrium-aluminum-garnet (Er:YAG) laser, photodynamic therapy (PDT), and CHX only, for reducing biofilm vitality from implant-like titanium surfaces. STUDY DESIGN/MATERIALS AND METHODS: The study involved eight volunteers, each receiving a custom mouth device containing eight titanium discs. The volunteers were requested to wear the device for 72 h for biofilm development. Fluorescence microscopy was used to evaluate the remaining biofilm with a two-component nucleic acid dye kit. The vital residual biofilm was quantified as a percentage of the surface area using image analysis software. Sixty-four titanium discs were assigned randomly to one of four treatment groups. RESULTS: The percentage of titanium disc area covered by vital residual biofilm was 43.9% (7.7%), 32.2% (7.0%), 56.6% (3.6%), and 73.2% (7.8%) in the PDT, Er:YAG, CHX, and control groups, respectively (mean (SD)). Compared to the control group, the treatment groups showed significant differences in the area covered by residual biofilm (P < 0.001). CHX combined with Er:YAG laser treatment was superior to CHX combined with PDT, and CHX only was better than the control. CONCLUSION: Within the current in vitro model's limitations, CHX combined with Er:YAG laser treatment is a valid method to reduce biofilm vitality on titanium discs.

Cranioplasty with hydroxyapatite or acrylic is associated with a reduced risk of all-cause and infection-associated explantation.

OBJECTIVE: Cranioplasty remains an essential procedure following craniectomy but is associated with high morbidity. We investigated factors associated with outcomes following first alloplastic cranioplasty. METHODS: A single-centre, retrospective cohort study of patients undergoing first alloplastic cranioplasty at a tertiary neuroscience centre (01 March 2010-01 September 2021). Patient demographics and craniectomy/cranioplasty details were extracted. Primary outcome was all-cause explantation. Secondary outcomes were explantation secondary to infection, surgical morbidity and mortality. Multivariable analysis was performed using Cox proportional hazards regression or binary logistic regression. RESULTS: Included were 287 patients with a mean age of 42.9 years [SD = 15.4] at time of cranioplasty. The most common indication for craniectomy was traumatic brain injury (32.1%, n = 92). Cranioplasty materials included titanium plate (23.3%, n = 67), hydroxyapatite (22.3%, n = 64), acrylic (20.6%, n = 59), titanium mesh (19.2%, n = 55), hand-moulded PMMA cement (9.1%, n = 26) and PEEK (5.6%, n = 16). Median follow-up time after cranioplasty was 86.5 months (IQR 44.6-111.3). All-cause explantation was 12.2% (n = 35). Eighty-three patients (28.9%) had surgical morbidity. In multivariable analysis, the risk of all-cause explantation and explantation due to infection was reduced with the use of both hydroxyapatite (HR 0.22 [95% CI 0.07-0.71], p = .011, HR 0.22 [95% CI 0.05-0.93], p = .040) and acrylic (HR 0.20 [95% CI 0.06-0.73], p = .015, HR 0.24 [95% CI 0.06-0.97], p = .045), respectively. In addition, risk of explantation due to infection was increased when time to cranioplasty was between three and six months (HR 6.38 [95% CI 1.35-30.19], p = .020). Mean age at cranioplasty (HR 1.47 [95% CI 1.03-2.11], p = .034), titanium mesh (HR 5.36 [95% CI 1.88-15.24], p = .002), and use of a drain (HR 3.37 [95% CI 1.51-7.51], p = .003) increased risk of mortality. CONCLUSIONS: Morbidity is high following cranioplasty, with over a tenth requiring explantation. Hydroxyapatite and acrylic were associated with reduced risk of all-cause explantation and explantation due to infection. Cranioplasty insertion at three to six months was associated with increased risk of explantation due to infection.

Efficacy of strontium supplementation on implant osseointegration under osteoporotic conditions: A systematic review.

STATEMENT OF PROBLEM: Strontium has been validated for potent bone-seeking and antiosteoporotic properties and elicits a potentially beneficial impact on implant osseointegration in patients with osteoporosis. However, the efficacy of strontium supplementation on improving new bone formation and implant osseointegration in the presence of osteoporotic bone is still unclear. PURPOSE: The purpose of this systematic review was to comprehensively assess the efficacy of strontium supplementation, encompassing oral intake and local delivery of strontium, on implant osseointegration in patients with osteoporosis. MATERIAL AND METHODS: Searches on electronic databases (MEDLINE or PubMed, Web of Science, EBSCO, Embase, and Clinicaltrials.gov) and manual searches were conducted to identify relevant preclinical animal trials up to June 2020. The primary outcomes were the percentage of bone-implant contact and bone area; the secondary outcomes were quantitative parameters of biomechanical tests and microcomputed tomography (µCT). RESULTS: Fourteen preclinical trials (1 rabbit, 1 sheep, and 12 rat), with a total of 404 ovariectomized animals and 798 implants, were eligible for analysis. The results revealed a significant 17.1% increase in bone-implant contact and 13.5% increase in bone area, favoring strontium supplementation despite considerable heterogeneity. Subgroup analyses of both bone-implant contact and bone area exhibited similar outcomes with low to moderate heterogeneity. Results of biomechanical and µCT tests showed that strontium-enriched implantation tended to optimize the mechanical strength and microarchitecture of newly formed bone despite moderate to generally high heterogeneity. CONCLUSIONS: Based on the available preclinical evidence, strontium supplementation, including local and systemic delivery, showed promising results for enhancing implant osseointegration in the presence of osteoporosis during 4 to 12 weeks of healing. Future well-designed standardized studies are necessary to validate the efficacy and safety of strontium supplementation and to establish a standard methodology for incorporating Sr into implant surfaces in a clinical setting.

Low-Molecular-Weight Heparins (LMWH) and Synthetic Factor X Inhibitors Can Impair the Osseointegration Process of a Titanium Implant in an Interventional Animal Study.

Background and objectives: Cementless total hip arthroplasty is a common surgical procedure and perioperative thromboprophylaxis is used to prevent deep vein thrombosis or pulmonary embolism. Osseointegration is important for long-term implant survival, and there is no research on the effect of different thromboprophylaxis agents on the process of osseointegration. Materials and Methods: Seventy rats were allocated as follows: Group I (control group), Group II (enoxaparin), Group III (nadroparin), and Group IV (fondaparinux). Ovariectomy was performed on all subjects, followed by the introduction of an intramedullary titanium implant into the femur. Thromboprophylaxis was administered accordingly to each treatment group for 35 days postoperatively. Results: Group I had statistically significantly lower anti-Xa levels compared to treatment groups. Micro-CT analysis showed that nadroparin had lower values compared to control in bone volume (0.12 vs. 0.21, p = 0.01) and percent bone volume (1.46 vs. 1.93, p = 0.047). The pull-out test showed statistically significant differences between the control group (8.81 N) compared to enoxaparin, nadroparin, and fondaparinux groups (4.53 N, 4 N and 4.07 N, respectively). Nadroparin had a lower histological cortical bone tissue and a higher width of fibrous tissue (27.49 µm and 86.9 µm) at the peri-implant area, compared to control (43.2 µm and 39.2 µm), enoxaparin (39.6 µm and 24 µm), and fondaparinux (36.2 µm and 32.7 µm). Conclusions: Short-term administration of enoxaparin, nadroparin, and fondaparinux can reduce the osseointegration of titanium implants, with nadroparin having the most negative effect. These results show that enoxaparin and fondaparinux are preferred to be administered due to a lesser negative impact on the initial implant fixation.

Sunscreens and their usefulness: have we made any progress in the last two decades?

Sunscreens have now been around for decades to mitigate the Sun's damaging ultraviolet (UV) radiation which, although essential for the existence of life, is a recognized prime carcinogen. Accordingly, have suncreams achieved their intended purposes towards protection against sunburns, skin photo-ageing and the like? Most importantly, however, have they provided the expected protection against skin cancers that current sunscreen products claim to do? In the last two decades, there have been tens, if not hundreds of studies on sunscreens with respect to skin protection against UVB (280‒320 nm)-traditionally sunscreens with rather low sun protection factors (SPF) were intended to protect against this type of radiation-and UVA (320‒400 nm) radiation; a distinction between SPF and UVA protection factor (UVA-PF) is made. Many of the studies of the last two decades have focused on protection against the more skin-penetrating UVA radiation. This non-exhaustive article reviews some of the important facets of what is currently known about sunscreens with regard (i) to the physical UV filters titanium dioxide (TiO2) and zinc oxide (ZnO) and the mostly photo-unstable chemical UVB/UVA filters (e.g., octinoxate (OMC) and avobenzone (AVO), among others), (ii) to novel chemical sunscreen agents, (iii) to means that minimize the breakdown of chemical filters and improve their stability when exposed to UV sunlight, (iv) to SPF factors, and (v) to a short discussion on non-melanoma skin cancers and melanoma. Importantly, throughout the article we allude to the safety aspects of sunscreens and at the end ask the question: do active ingredients in sunscreen products pose a risk to human health, and what else can be done to enhance protection? Significant loss of skin protection from two well-known commercial suncreams when exposed to simulated UV sunlight. Cream I: titanium dioxide, ethylhexyl triazone, avobenzone, and octinoxate; Cream II: octyl salicylate, oxybenzone, avobenzone, and octinoxate.

No clinical difference between TiN-coated versus uncoated cementless CoCrMo mobile-bearing total knee arthroplasty; 10-year follow-up of a randomized controlled trial.

PURPOSE: Improvement of biomechanical properties of cobalt-chromium-molybdenum (CoCrMo) implant surface and reduction of adhesive wear is achieved by titanium-nitride (TiN) coating in vitro. Less pain, higher postoperative outcome scores and a lower revision rate after TKA with a TiN-coated CoCrMo TKA compared with uncoated CoCrMo TKA after 10-year follow-up was hypothesized. METHODS: In a double-blinded RCT, 101 patients received a cementless mobile-bearing CoCrMo TKA, either TiN-coated or uncoated. The primary outcome measure was the visual analogue scale (VAS) score for pain and secondary outcome measures were the Knee Society Score (KSS), Oxford Knee Score (OKS), revision rate and adverse events. Patients were assessed at 6 weeks, 6 months, 1 year, 5 years and 10 years, postoperatively. RESULTS: 68 patients (67%) were available for 10-year follow-up. No difference was found in any of the assessed outcome measures with a mean decrease in VAS score (31.6 ± 22.9) and a mean increase in OKS (10.9 ± 8.4), KSS (29.3 ± 31.4), KSSK (26.4 ± 18.2) and KSSF (4.1 ± 22.9). Overall revision rate was 7% (coated 6% vs uncoated 8%) without additional revision procedures between 5 and 10-year follow-up. CONCLUSIONS: The in vitro potential benefits of TiN coating did not result in better clinical outcome when compared to an uncoated cementless TKA. Pain, functional outcome and revision rates were comparable after 10-year follow-up. TiN-coated cementless TKA provides comparable good long-term results, similar to uncoated cementless CoCrMo TKA. LEVEL OF EVIDENCE: Level 1, Therapeutic Study NETHERLANDS TRIAL REGISTER: NL2887/NTR3033.

Influence of Nano, Micro, and Macro Topography of Dental Implant Surfaces on Human Gingival Fibroblasts.

Current research on dental implants has mainly focused on the influence of surface roughness on the rate of osseointegration, while studies on the development of surfaces to also improve the interaction of peri-implant soft tissues are lacking. To this end, the first purpose of this study was to evaluate the response of human gingival fibroblasts (hGDFs) to titanium implant discs (Implacil De Bortoli, Brazil) having different micro and nano-topography: machined (Ti-M) versus sandblasted/double-etched (Ti-S). The secondary aim was to investigate the effect of the macrogeometry of the discs on cells: linear-like (Ti-L) versus wave-like (Ti-W) surfaces. The atomic force microscopy (AFM) and scanning electron microscopy (SEM) analysis showed that the Ti-S surfaces were characterized by a significantly higher micro and nano roughness and showed the 3D macrotopography of Ti-L and Ti-W surfaces. For in vitro analyses, the hGDFs were seeded into titanium discs and analyzed at 1, 3, and 5 days for adhesion and morphology (SEM) viability and proliferation (Cck-8 and MTT assays). The results showed that all tested surfaces were not cytotoxic for the hGDFs, rather the nano-micro and macro topography favored their proliferation in a time-dependent manner. Especially, at 3 and 5 days, the number of cells on Ti-L was higher than on other surfaces, including Ti-W surfaces. In conclusion, although further studies are needed, our in vitro data proved that the use of implant discs with Ti-S surfaces promotes the adhesion and proliferation of gingival fibroblasts, suggesting their use for in vivo applications.

Effectiveness of the Sequential Use of Plastic and Titanium Implants for Experimental Replacement of the Mandibular Defect in Animals Using Preliminary Digital Design.

Using the templates preliminarily made by 3D design and prototyping methods, defects in the lateral area of the lower jaw of sheep were created using the piezosurgical technique. The defects were replaced by plastic implants obtained by the method of layer-by-layer fusion of the FDM printing-fusing deposition modeling and fixation with titanium screws to the jaw body. In the time interval, plastic implants are replaced by titanium implants obtained by selective laser sintering (SLS) using a 3D printer. To study the processes of reparative osteogenesis, microsamples of tissues of the preimplantation zone were analyzed. As a result, signs of osteo- and fibro-osseointegration were identified. The obtained data are regarded as a prerequisite for further clinical trials of the developed protocols for the sequential replacement of jaw defects using 3D printing.

Reduction of SOST gene promotes bone formation through the Wnt/ß-catenin signalling pathway and compensates particle-induced osteolysis.

The increase in bone resorption and/or the inhibition of bone regeneration caused by wear particles are the main causes of periprosthetic osteolysis. The SOST gene and Sclerostin, a protein synthesized by the SOST gene, are the characteristic marker of osteocytes and regulate bone formation and resorption. We aimed to verify whether the SOST gene was involved in osteolysis induced by titanium (Ti) particles and to investigate the effects of SOST reduction on osteolysis. The results showed osteolysis on the skull surface with an increase of sclerostin levels after treated with Ti particles. Similarly, sclerostin expression in MLO-Y4 osteocytes increased when treated with Ti particles in vitro. After reduction of SOST, local bone mineral density and bone volume increased, while number of lytic pores on the skull surface decreased and the erodibility of the skull surface was compensated. Histological analyses revealed that SOST reduction increased significantly alkaline phosphatase- (ALP) and osterix-positive expression on the skull surface which promoted bone formation. ALP activity and mineralization of MC3T3-E1 cells also increased in vitro when SOST was silenced, even if treated with Ti particles. In addition, Ti particles decreased ß-catenin expression with an increase in sclerostin levels, in vivo and in vitro. Inversely, reduction of SOST expression increased ß-catenin expression. In summary, our results suggested that reduction of SOST gene can activate the Wnt/ß-catenin signalling pathway, promoting bone formation and compensated for bone loss induced by Ti particles. Thus, this study provided new perspectives in understanding the mechanisms of periprosthetic osteolysis.

Patients' satisfaction and safety of bulk injection therapy Urolastic for treatment of stress urinary incontinence: A cross-sectional study.

AIMS: Primary outcome was to evaluate patients' satisfaction after being treated with bulk injection therapy polydimethylsiloxane Urolastic (PDMS-U) for stress urinary incontinence (SUI). Secondary outcomes were: subjective cure, objective cure, severity of SUI symptoms, complications, reintervention rate, and disease-specific quality of life. Furthermore, to determine if outcomes worsened during time-after-treatment (time-frames: 0-12, 13-24, and ≥25 months). METHODS: In a cross-sectional design, patients treated with PDMS-U were recruited for hospital revisit. The primary outcome, patients' satisfaction, was assessed by the surgical satisfaction questionnaire. Subjective cure, objective cure, and severity of symptoms were assessed by the patients global impression of improvement, standardized cough stress test, and Sandvik severity scale, respectively. Medical charts and face-to-face interviews were used to determine complications and reinterventions. RESULTS: About 110 patients participated, 87 revisited the hospital. Median follow-up was 25 months (interquartile range: 14;35 months). Patients' satisfaction rate was 51%. Subjective and objective cure were respectively 46% and 47%. Most prevalent complications were: urinary retention (22%), pain (15%), and dyspareunia (15%). Exposure and erosion occurred in 7% and 5%, respectively. Reintervention rate of reinjection and excision of bulk material was 6% and 18.0%, respectively. Objective cure significantly worsened during time-after-treatment (P = < .05). CONCLUSIONS: About half of the patients being treated with PDMS-U were satisfied and subjectively cured 2 years after treatment, although the majority still experienced symptoms of SUI. Most complications were mild and transient, however, in 18% excision of bulk material was indicated for severe or persistent complications such as pain, exposure, or erosion.

Idiopathic Early-onset Scoliosis: Growing Rods Versus Vertically Expandable Prosthetic Titanium Ribs at 5-year Follow-up.

BACKGROUND: Distraction-based techniques allow spinal growth until skeletal maturity while preventing curve progression. METHODS: Two multicenter early-onset scoliosis databases were used to identify patients with idiopathic spine abnormalities treated with traditional growing rods (TGR) or vertically expandable titanium ribs (VEPTR). Patients underwent at least 4 lengthenings and had at least 5-year follow-up. Significance was set at P<0.05. RESULTS: In total, 50 patients treated with TGR and 22 treated with VEPTR were included. Mean (±SD) age at surgery was 5.5 (±2.0) years for the TGR group versus 4.3 (±1.9) years for the VEPTR group (P=0.044); other demographic parameters were similar. VEPTR patients had more procedures (mean 15±4.2) than TGR patients (mean 10±4.0) (P=0.001). Unilateral constructs were present in 18% (4 of 22) of VEPTR and 16% (8 of 50) of TGR patients. Bilateral constructs spanned a mean 2.1 additional surgical levels and exposed patients to 1.6 fewer procedures than unilateral constructs. Curve correction was similar between bilateral and unilateral constructs. TGR patients experienced greater curve correction (50%) than VEPTR patients (27%) (P<0.001) and achieved a greater percentage of thoracic height gain (24%) than VEPTR patients (12%) (P=0.024). At latest follow-up, TGR patients had better maintenance of curve correction, less kyphosis, and 15% greater absolute gain in thoracic height versus VEPTR patients. TGR patients had a lower rate of wound complications (14%) than VEPTR patients (41%) (P=0.011). CONCLUSIONS: In patients with idiopathic early-onset scoliosis, TGRs produced greater initial curve correction, greater thoracic height gains, less kyphosis, and lower incidence of wound complications compared with VEPTR. LEVEL OF EVIDENCE: Level III.

The Body's Cellular and Molecular Response to Protein-Coated Medical Device Implants: A Review Focused on Fibronectin and BMP Proteins.

Recent years have seen a marked rise in implantation into the body of a great variety of devices: hip, knee, and shoulder replacements, pacemakers, meshes, glucose sensors, and many others. Cochlear and retinal implants are being developed to restore hearing and sight. After surgery to implant a device, adjacent cells interact with the implant and release molecular signals that result in attraction, infiltration of the tissue, and attachment to the implant of various cell types including monocytes, macrophages, and platelets. These cells release additional signaling molecules (chemokines and cytokines) that recruit tissue repair cells to the device site. Some implants fail and require additional revision surgery that is traumatic for the patient and expensive for the payer. This review examines the literature for evidence to support the possibility that fibronectins and BMPs could be coated on the implants as part of the manufacturing process so that the proteins could be released into the tissue surrounding the implant and improve the rate of successful implantation.

Does cup position differ between trabecular metal and titanium cups? A radiographic propensity score matched study of 300 hips.

Background and purpose - The use of trabecular metal cups in primary total hip arthroplasty (THA) is increasing, despite the survival of Continuum cups being slightly inferior compared with other uncemented cups in registries. This difference is mainly explained by a higher rate of dislocation revisions. Cup malpositioning is a risk factor for dislocation and, being made of a highly porous material, Continuum cups might be more difficult to position. We evaluated whether Continuum cups had worse cup positioning compared with other uncemented cups. Patients and methods - Based on power calculation, 150 Continuum cups from 1 center were propensity score matched with 150 other uncemented cups from 4 centers. All patients had an uncemented stem, femoral head size of 32 mm or 36 mm, and BMI between 19 and 35. All operations were done for primary osteoarthrosis through a posterior approach. Patients were matched using age, sex, and BMI. Cup positioning was measured from anteroposterior pelvic radiograph using the Martell Hip Analysis Suite software. Results - There was no clinically relevant difference in mean inclination angle between the study group and the control group (43° [95% CI 41-44] and 43° [CI 42-45], respectively). The study group had a larger mean anteversion angle compared with the control group, 19° (CI 18-20) and 17° (CI 15-18) respectively. Interpretation - Continuum cups had a greater anteversion compared with the other uncemented cups. However, the median anteversion was acceptable in both groups and this difference does not explain the larger dislocation rate in the Continuum cups observed in earlier studies.

Bulking for stress urinary incontinence in men: A systematic review.

AIMS: An updated literature review on outcomes in men treated with currently commercially available bulking agents was performed to determine whether this is a reasonable option in selected patients. METHODS: The review adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses framework of systematic reviews. A comprehensive search of PubMed, Medline, and Embase was undertaken. Abstracts were independently screened by two investigators to include men with stress urinary incontinence treated with a peri-urethral injection of bulking agents currently available in the market. RESULTS: Only eight original articles met the inclusion criteria. The bulking agents used were Macroplastique in five studies (total 123 patients), Opsys, Durasphere, and Urolastic in one study each (10, 7, and 2 patients, respectively). Only one study was randomized; Macroplastique vs AUS in men with mild or total incontinence. The included populations were heterogeneous and encompassed endoscopic, perineal, abdominal and laparoscopic prostate surgery as well as spinal cord injuries and urethral sphincter insufficiency. Significant dissimilarity was evident for the duration of incontinence (9-108 months), mean volume of bulking agent used (2.3-13.5 mL), number of cushions (1-5), depth and position of the cushions. The outcomes varied significantly, with reported dry rates between 0% and 83%. Outcomes were limited by relatively short follow-up in most studies. CONCLUSION: Following initial enthusiasm and then dismay with collagen-based compounds, sparse and heterogeneous literature data were produced on newer non-migrating and nonabsorbable bulking agents. Some studies have suggested encouraging, if short term outcomes, however, future studies are needed in this field to support recommendations for widespread use.

Protective Effect of 4% Titanium Tetrafluoride Varnish on Dentin Demineralization Using a Microcosm Biofilm Model.

This study evaluated the effect of titanium tetrafluoride (TiF4) varnish on the development of dentin carious lesions. Bovine root dentin samples were treated for 6 h with: (A) 4% TiF4 varnish (2.45% F); (B) 5.42% sodium fluoride (NaF) varnish (2.45% F); (C) 2% chlorhexidine (CHX) gel - positive control; (D) placebo varnish; or (E) untreated - negative control (n = 4 × biological triplicate, n = 12). Treated dentin samples were exposed to human saliva mixed with McBain saliva (1:50) for the first 8 h in 24-well plates. Thereafter, the medium was removed, and McBain saliva containing 0.2% sucrose was applied for 16 h. From days 2 to 5, McBain saliva with sucrose was replaced daily (37°C, 5% CO2). The demineralization was measured using transverse microradiography, while the effect on biofilm was analyzed using viability, extracellular polysaccharide (EPS), and lactic acid production assays. The data were statistically analyzed (p < 0.05). All treatments (fluorides and CHX) significantly reduced the biofilm viability compared to placebo varnish and negative control. However, none of them was able to reduce the colony-forming unit counting for total microorganism, total streptococci, and Streptococcus mutans. NaF significantly reduced the number of Lactobacillus sp. compared to negative control. No effect was seen on lactic acid production neither on EPS synthesis, except that CHX significantly reduced the amount of insoluble EPS. Both fluorides were able to reduce dentin demineralization compared to placebo varnish and negative control; TiF4 had a better effect in reducing mineral loss and lesion depth than NaF. Therefore, TiF4 varnish has the best protective effect on dentin carious lesion formation using this model.

The Use of Microplates for Internal Fixation of Comminuted Mandibular Fractures.

BACKGROUND: Although clinical trials have successfully applied microplates for the internal fixation of single or double isolated mandibular fractures, the use of microplate systems in comminuted mandibular fractures is not widely accepted. This study aimed to evaluate the use of microplates for internal fixation of comminuted mandible fractures and to discuss their applicability. METHODS: Fourteen patients with comminuted mandibular fractures (10 at a single region, 3 at 2 regions, and 1 at 4 regions) were treated with open reduction and internal fixation using 0.5- or 0.6-mm-thick titanium microplates and 1.0-, 1.2-, or 1.3-mm monocortical microscrews. Three-level fixation at the lower border, upper border (as interdental wiring), and middle of the mandible was performed. Maxillomandibular fixation was applied only when premature occlusal contact was observed after fracture fixation. RESULTS: During the follow-up period (3-55 months), all fractures showed favorable and complete bone healing. Six patients experienced minor complications, including minimal malocclusion (n = 5) and a localized infection (n = 1). Most of these complications were managed with conservative treatment. No major complications that required further orthodontic treatment or reoperation occurred. CONCLUSIONS: These results suggest that 3-level fixation using microplates is appropriate for the reconstruction of comminuted mandibular fractures without bony defects. The small size and malleability of these devices facilitate accurate anatomical reduction for complete contact of the comminuted bony segments by multiple fixation. Furthermore, microplates allow for preservation of sufficient periosteal blood supply and restoration of premorbid occlusion (by occlusal self-adjustment) while providing sufficient stability.

Self-releasing of a titanium clamp (CranioFix) in cranioplasty.

The CranioFix® titanium clamp was developed for fixing bone flaps after craniotomy. In this case, to prevent cosmetic problems, the bone flaps were trimmed with a beveled edge, and a CranioFix clamp was used for bone flap fixation. As the brain swelled, the CranioFix clamp became loosened. If brain swelling is anticipated and bone margins have been trimmed, it may be better to consider other fixation methods.