A Novel Approach for the Treatment of Recurrent Oroantral Fistula Occurring at an Infected Sinus Augmentation Site.

Closing a recurrent oroantral fistula (OAF) that occurs at an infected sinus augmentation site is a challenge for clinicians. The recurrent OAF has a detrimental impact on bone regeneration and subsequent implant placement. This case report includes three cases in which sinus graft infection and OAF occurred after maxillary sinus augmentation (MSA). In these cases, treatments to control sinus infection were performed using an otolaryngologist; then, intraoral interventions comprising mucosal flap procedures, bone grafts, and barrier membrane applications were performed 2-5 times by oral surgeons. Nevertheless, OAF recurred persistently. The failure to stop OAF recurrence may be due to the inability to effectively block air pressure at the OAF site. Following a comprehensive debridement of the infected tissue at the previous sinus augmentation site, a pouch was created through sinus mucosal elevation. The perforated sinus mucosa at the OAF site was covered with a non-resorbable membrane in one case and with resorbable collagen membranes in the other two cases, followed by bone grafting within the pouch. Lastly, this procedure was completed by blocking the entrance of the pouch with a cortical bone shell graft and a resorbable collagen membrane. The cortical bone shell graft, obstructing the air pressure from the nasal cavity, facilitated bone formation, and, ultimately, allowed for implant placement. Within the limitations of the present case report, the application of a guided bone regeneration technique involving a cortical bone shell graft and a barrier membrane enabled the closure of the recurrent OAF and subsequent implant placement.

Influence of Surface Contaminants and Hydrocarbon Pellicle on the Results of Wettability Measurements of Titanium.

Hydrophilicity/hydrophobicity-or wettability-is a key surface characterization metric for titanium used in dental and orthopedic implants. However, the effects of hydrophilicity/hydrophobicity on biological capability remain uncertain, and the relationships between surface wettability and other surface parameters, such as topography and chemistry, are poorly understood. The objective of this study was to identify determinants of surface wettability of titanium and establish the reliability and validity of the assessment. Wettability was evaluated as the contact angle of ddH2O. The age of titanium specimens significantly affected the contact angle, with acid-etched, microrough titanium surfaces becoming superhydrophilic immediately after surface processing, hydrophobic after 7 days, and hydrorepellent after 90 days. Similar age-related loss of hydrophilicity was also confirmed on sandblasted supra-micron rough surfaces so, regardless of surface topography, titanium surfaces eventually become hydrophobic or hydrorepellent with time. On age-standardized titanium, surface roughness increased the contact angle and hydrophobicity. UV treatment of titanium regenerated the superhydrophilicity regardless of age or surface roughness, with rougher surfaces becoming more superhydrophilic than machined surfaces after UV treatment. Conditioning titanium surfaces by autoclaving increased the hydrophobicity of already-hydrophobic surfaces, whereas conditioning with 70% alcohol and hydrating with water or saline attenuated pre-existing hydrophobicity. Conversely, when titanium surfaces were superhydrophilic like UV-treated ones, autoclaving and alcohol cleaning turned the surfaces hydrorepellent and hydrophobic, respectively. UV treatment recovered hydrophilicity without exception. In conclusion, surface roughness accentuates existing wettability and can either increase or decrease the contact angle. Titanium must be age-standardized when evaluating surface wettability. Surface conditioning techniques significantly but unpredictably affect existing wettability. These implied that titanium wettability is significantly influenced by the hydrocarbon pellicle and other contaminants inevitably accumulated. UV treatment may be an effective strategy to standardize wettability by making all titanium surfaces superhydrophilic, thereby allowing the characterization of individual surface topography and chemistry parameters in future studies.

Successful Implant Placement via Simultaneous Nasal Floor Augmentation in an Inferior Meatus Pneumatization Case.

Partially edentulous patients who present with inadequate bone height in the posterior maxillary can predictably be rehabilitated with lateral wall sinus augmentation and subsequent implant placement. However, the sinus augmentation is defined by variations observed in the anatomical presentation of the maxillary sinus. Herein, we describe a case study managing sinus augmentation when a rare anatomic variant termed inferior meatus pneumatization was observed. A 65-year-old female patient presented, wherein the inferior meatus of the nasal cavity was located directly above the maxillary posterior dentition as opposed to the maxillary sinus. The clinically atrophied maxilla was rehabilitated by employing nasal floor elevation, bone augmentation, and simultaneous implant placement. Post-operatively, no sino-nasal complications were recorded. Subsequently, 8 months after the initial procedure, osteointegration of the implants along with the presence of vital bone was observed. The patient posterior occlusion in the upper right quadrant was rehabilitated by engaging the stable implants with a cement-retained fixed final prosthesis. Follow-ups recorded for up to 2 years demonstrated no further complications. The case report demonstrates diagnosis, appropriate treatment, and management of inferior meatus pneumatization and a viable surgical approach for augmentation and implant treatment.

Periodontal Phenotype Modification Using Subepithelial Connective Tissue Graft and Bone Graft in the Mandibular Anterior Teeth with Mucogingival Problems Following Orthodontic Treatment.

Among the complications of orthodontic treatment, mucogingival problems with gingival recession in the mandibular anterior teeth are challenging for clinicians. Mucogingival problems can lead to esthetic deficits, thermal hypersensitivity, tooth brushing pain, and complicated plaque control. Herein, we present a case of a 16-year-old female with gingival recession in the left mandibular central incisor after orthodontic treatment. The preoperative clinical findings showed a thin soft tissue biotype with root prominence in the mandibular anterior area. The interdental area was relatively depressed. After reflection of the full-thickness flap, root coverage using a bone graft substitute and subepithelial connective tissue graft obtained from the palatal mucosa was performed. The 6-month and 5-year postoperative clinical findings showed improved soft tissue phenotype. The cross-sectional CBCT scans 5 years after surgery showed a well-maintained labial bone plate in the mandibular incisors. Within the limitations of this case report, for patients with gingival recession in the mandibular incisors after orthodontic treatment, a successful biotype modification can be achieved with a combined procedure using subepithelial connective tissue graft with bone graft substitutes.

Submerged Technique of Partially De-Epithelialized Free Gingival Grafts for Gingival Phenotype Modification in the Maxillary Anterior Region: A Case Report of a 34-Year Follow-up.

A coronally advanced flap combined with a subepithelial connective tissue graft is considered the gold standard for achieving root coverage on exposed root surfaces. Nevertheless, challenges arise when this technique is applied to multiple teeth and when the palatal soft tissue is very thin. Several surgical modifications have been reported to simultaneously achieve both single or multiple root coverage and widening of the keratinized gingiva. In this context, there have been no reported cases utilizing the submerged technique with partially de-epithelialized free gingival grafts. We intend to introduce a submerged technique involving partially de-epithelialized free gingival grafts for the modification of soft tissue phenotypes in the maxillary anterior region.

Successful Management of Apically Exposed Implants in the Maxillary Sinus and Associated Sinus Pathologies Via Maxillary Sinus Floor Augmentation.

One common complication with dental implants placed in the atrophic posterior maxilla, especially with simultaneous transcrestal sinus augmentation, is the implant protruding into the sinus without apical bone support. Frequently, apically exposed implants contribute to various sinus pathologies that may lead to implant failure. Treatment options include (1) managing asymptomatic sinus pathology; (2) regrafting the apically exposed portion of the implant(s); and (3) removing the implant and placing a new implant with simultaneous grafting. The purpose of this case report is to present 4 clinical cases of apically exposed implants in the maxillary sinus. The report will cover: (1) exposed implants with asymptomatic sinus pathologies and (2) show successful management of protruding implants and pathologies using maxillary sinus floor augmentation. Various methods of implant surface detoxification, mechanical and chemical, are described for predictable bone remodeling around existing implants as well as newly installed implants. After 6 months of healing, osseointegration was well achieved for all implants and sinonasal complications were not observed. Clinical photographs and 3-dimensional imaging of surgical sites were used to validate clinical assessments.

Use of a Lateral Sinus Bony Window as an Intraoral Donor Site for Guided Bone Regeneration in Wide Post-Extraction Defects.

Maxillary sinus augmentation (MSA) and guided bone regeneration (GBR) have shown successful clinical, radiological, and histological outcomes for implant-related bone reconstruction and have been used to augment bony defects of various shapes and sizes. This study demonstrated that the lateral sinus bony window obtained during MSA can be used as an autogenous block bone graft for the augmentation of wide post-extraction defects. During the uncovering procedure performed 6 months after surgery, the grafted lateral bony window was well integrated with the adjacent native bone, and complete bone filling was observed in all bony defects around the implants. All of the implants survived. Within the limitations of this study, autogenous block bone obtained from lateral window sites can be used as novel donors for the resolution of wide bony defects around implants.

Ultraviolet Treatment of Titanium to Enhance Adhesion and Retention of Oral Mucosa Connective Tissue and Fibroblasts.

Peri-implantitis is an unsolved but critical problem with dental implants. It is postulated that creating a seal of gingival soft tissue around the implant neck is key to preventing peri-implantitis. The objective of this study was to determine the effect of UV surface treatment of titanium disks on the adhesion strength and retention time of oral connective tissues as well as on the adherence of mucosal fibroblasts. Titanium disks with a smooth machined surface were prepared and treated with UV light for 15 min. Keratinized mucosal tissue sections (3 × 3 mm) from rat palates were incubated for 24 h on the titanium disks. The adhered tissue sections were then mechanically detached by agitating the culture dishes. The tissue sections remained adherent for significantly longer (15.5 h) on the UV-treated disks than on the untreated control disks (7.5 h). A total of 94% of the tissue sections were adherent for 5 h or longer on the UV-treated disks, whereas only 50% of the sections remained on the control disks for 5 h. The adhesion strength of the tissue sections to the titanium disks, as measured by tensile testing, was six times greater after UV treatment. In the culture studies, mucosal fibroblasts extracted from rat palates were attached to titanium disks by incubating for 24, 48, or 96 h. The number of attached cells was consistently 15-30% greater on the UV-treated disks than on the control disks. The cells were then subjected to mechanical or chemical (trypsinization) detachment. After mechanical detachment, the residual cell rates on the UV-treated surfaces after 24 and 48 h of incubation were 35% and 25% higher, respectively, than those on the control surfaces. The remaining rate after chemical detachment was 74% on the control surface and 88% on the UV-treated surface for the cells cultured for 48 h. These trends were also confirmed in mouse embryonic fibroblasts, with an intense expression of vinculin, a focal adhesion protein, on the UV-treated disks even after detachment. The UV-treated titanium was superhydrophilic, whereas the control titanium was hydrophobic. X-ray photoelectron spectroscopy (XPS) chemical analysis revealed that the amount of carbon at the surface was significantly reduced after UV treatment, while the amount of TiOH molecules was increased. These ex vivo and in vitro results indicate that the UV treatment of titanium increases the adhesion and retention of oral mucosa connective tissue as a result of increased resistance of constituent fibroblasts against exogenous detachment, both mechanically and chemically, as well as UV-induced physicochemical changes of the titanium surface.

Tuning of Titanium Microfiber Scaffold with UV-Photofunctionalization for Enhanced Osteoblast Affinity and Function.

Titanium (Ti) is an osteoconductive material that is routinely used as a bulk implant to fix and restore bones and teeth. This study explored the effective use of Ti as a bone engineering scaffold. Challenges to overcome were: (1) difficult liquid/cell infiltration into Ti microfiber scaffolds due to the hydrophobic nature of Ti; and (2) difficult cell attachment on thin and curved Ti microfibers. A recent discovery of UV-photofunctionalization of Ti prompted us to examine its effect on Ti microfiber scaffolds. Scaffolds in disk form were made by weaving grade 4 pure Ti microfibers (125 µm diameter) and half of them were acid-etched to roughen the surface. Some of the scaffolds with original or acid-etched surfaces were further treated by UV light before cell culture. Ti microfiber scaffolds, regardless of the surface type, were hydrophobic and did not allow glycerol/water liquid to infiltrate, whereas, after UV treatment, the scaffolds became hydrophilic and immediately absorbed the liquid. Osteogenic cells from two different origins, derived from the femoral and mandibular bone marrow of rats, were cultured on the scaffolds. The number of cells attached to scaffolds during the early stage of culture within 24 h was 3-10 times greater when the scaffolds were treated with UV. The development of cytoplasmic projections and cytoskeletal, as well as the expression of focal adhesion protein, were exclusively observed on UV-treated scaffolds. Osteoblastic functional phenotypes, such as alkaline phosphatase activity and calcium mineralization, were 2-15 times greater on UV-treated scaffolds, with more pronounced enhancement on acid-etched scaffolds compared to that on the original scaffolds. These effects of UV treatment were associated with a significant reduction in atomic carbon on the Ti microfiber surfaces. In conclusion, UV treatment of Ti microfiber scaffolds tunes their physicochemical properties and effectively enhances the attachment and function of osteoblasts, proposing a new strategy for bone engineering.

Novel Osteogenic Behaviors around Hydrophilic and Radical-Free 4-META/MMA-TBB: Implications of an Osseointegrating Bone Cement.

Poly(methyl methacrylate) (PMMA)-based bone cement, which is widely used to affix orthopedic metallic implants, is considered bio-tolerant but lacks osteoconductivity and is cytotoxic. Implant loosening and toxic complications are significant and recognized problems. Here we devised two strategies to improve PMMA-based bone cement: (1) adding 4-methacryloyloxylethyl trimellitate anhydride (4-META) to MMA monomer to render it hydrophilic; and (2) using tri-n-butyl borane (TBB) as a polymerization initiator instead of benzoyl peroxide (BPO) to reduce free radical production. Rat bone marrow-derived osteoblasts were cultured on PMMA-BPO, common bone cement ingredients, and 4-META/MMA-TBB, newly formulated ingredients. After 24 h of incubation, more cells survived on 4-META/MMA-TBB than on PMMA-BPO. The mineralized area was 20-times greater on 4-META/MMA-TBB than PMMA-BPO at the later culture stage and was accompanied by upregulated osteogenic gene expression. The strength of bone-to-cement integration in rat femurs was 4- and 7-times greater for 4-META/MMA-TBB than PMMA-BPO during early- and late-stage healing, respectively. MicroCT and histomorphometric analyses revealed contact osteogenesis exclusively around 4-META/MMA-TBB, with minimal soft tissue interposition. Hydrophilicity of 4-META/MMA-TBB was sustained for 24 h, particularly under wet conditions, whereas PMMA-BPO was hydrophobic immediately after mixing and was unaffected by time or condition. Electron spin resonance (ESR) spectroscopy revealed that the free radical production for 4-META/MMA-TBB was 1/10 to 1/20 that of PMMA-BPO within 24 h, and the substantial difference persisted for at least 10 days. The compromised ability of PMMA-BPO in recruiting cells was substantially alleviated by adding free radical-scavenging amino-acid N-acetyl cysteine (NAC) into the material, whereas adding NAC did not affect the ability of 4-META/MMA-TBB. These results suggest that 4-META/MMA-TBB shows significantly reduced cytotoxicity compared to PMMA-BPO and induces osteoconductivity due to uniquely created hydrophilic and radical-free interface. Further pre-clinical and clinical validations are warranted.

Biological and Physicochemical Characteristics of 2 Different Hydrophilic Surfaces Created by Saline-Storage and Ultraviolet Treatment.

OBJECTIVES: Hydrophilicity/hydrophobicity of titanium surfaces may affect osseointegration. Ordinary titanium surfaces are hydrophobic. Recently, 2 different methods of storing titanium in saline solution or treating it with ultraviolet (UV) light were introduced to generate surface hydrophilicity. This study compared biological and physicochemical properties of 2 different hydrophilic titanium surfaces created by these methods. MATERIALS: Acid-etched control, saline-stored, and UV-treated titanium surfaces were assessed by scanning electron microscopy, energy dispersive spectroscopy, and x-ray photoelectron spectroscopy. The attachment, spreading behaviors, mineralization, and gene expression of osteoblasts were examined. RESULTS: Similar microroughness was found on control and UV-treated surfaces, whereas foreign deposits were observed on saline-stored surfaces. Control and UV-treated surfaces consisted of Ti, O, and C, whereas saline-stored surfaces showed Na and Cl in addition to these 3 elements. Atomic percentage of surface carbon was higher in order of control, saline-stored, and UV-treated surfaces. Osteoblasts cultured on saline-stored surfaces showed higher levels of calcium deposition and collagen I expression than control. Osteoblasts on UV-treated surfaces showed significantly increased levels for all parameters related to cell attachment, cell spreading, the expression of adhesion and cytoskeletal proteins, mineralization, and gene expression compared with control, outperforming saline-stored surfaces for most parameters. CONCLUSION: Despite similar hydrophilicity, saline-stored and UV light-treated surfaces showed substantially different biological effects on osseointegration, associated with different surface chemistry and morphology.

Success rate and strength of osseointegration of immediately loaded UV-photofunctionalized implants in a rat model.

STATEMENT OF PROBLEM: Despite its clinical benefits, the immediate loading protocol might have a higher risk of implant failure than the regular protocol. Ultraviolet (UV) photofunctionalization is a novel surface enhancement technique for dental implants. However, the effect of photofunctionalization under loading conditions is unclear. PURPOSE: The purpose of this animal study was to evaluate the effect of photofunctionalization on the biomechanical quality and strength of osseointegration under loaded conditions in a rat model. MATERIAL AND METHODS: Untreated and photofunctionalized, acid-etched titanium implants were placed into rat femurs. The implants were immediately loaded with 0.46 N of constant lateral force. The implant positions were evaluated after 2 weeks of healing. The strength of osseointegration was evaluated by measuring the bone-implant interfacial breakdown point during biomechanical push-in testing. RESULTS: Photofunctionalization induced hydrophilic surfaces on the implants. Osseointegration was successful in 28.6% of untreated implants and 100% of photofunctionalized implants. The strength of osseointegration in successful implants was 2.4 times higher in photofunctionalized implants than in untreated implants. The degree of tilt of untreated implants toward the origin of force was twice that of photofunctionalized implants. CONCLUSIONS: Within the limit of an animal model, photofunctionalization significantly increased the success of osseointegration and prevented implant tilt. Even for the implants that underwent successful osseointegration, the strength of osseointegration was significantly higher for photofunctionalized implants than for untreated implants. Further experiments are warranted to determine the effectiveness of photofunctionalization on immediately loaded dental implants.

Effect of Photofunctionalization on Ti6Al4V Screw Stability Placed in Segmental Bone Defects in Rat Femurs.

PURPOSE: Ultraviolet-mediated photofunctionalization is a new technology to improve bone and titanium integration. We hypothesized that photofunctionalization would enhance the stability of titanium screws used for segmental bone defects. MATERIALS AND METHODS: Disks were prepared of a titanium alloy (Ti6Al4V) for an in vitro study to evaluate the attachment, proliferation, and differentiation of osteoblasts. Commercially available Ti6Al4V screws were used in vivo. Segmental bone defects were created in rat femurs as an immediate loading reconstruction model. The defects were reconstructed with commercially available titanium plates and Ti6Al4V screws, with or without photofunctionalization. The screw survival rates and mechanical stability were evaluated at 2 and 4 weeks, and the bone formation around the screws was analyzed. RESULTS: Osteoblasts showed greater attachment, proliferation, and differentiation on the photofunctionalized Ti6Al4V disks. Photofunctionalized screws had significantly greater survival rates and mechanical stability at 2 and 4 weeks. The bone formation around the photofunctionalized screws was significantly greater than that around the untreated screws at 4 weeks. CONCLUSIONS: The results of the present study have demonstrated the efficacy of photofunctionalization on enhancing the survival and stability of Ti6Al4V screws under a loaded condition in the reconstruction of segmental defects. This was associated with increased bioactivity and bone formation around the photofunctionalized Ti6Al4V material.

Effect of UV Photofunctionalization on Osseointegration in Aged Rats.

OBJECTIVES: This study evaluated the effect of photofunctionalization on osseointegration under the biologically adverse conditions of aging. MATERIALS: First of all, bone marrow-derived osteoblastic cells from young (8 weeks old) and aged (15 months old) rats were biologically characterized. Then, the osteoblasts from aged rats were seeded on titanium discs with and without photofunctionalization, and assessed for initial cell attachment and osteoblastic functions. Titanium mini-implants, with and without photofunctionalization, were placed in the femur of aged rats, and the strength of osseointegration was measured at week 2 of healing. Periimplant tissue was examined morphologically and chemically using scanning electron microscopy and energy dispersive x-ray spectroscopy, respectively. RESULTS: Cells from the aged rats showed substantially reduced biological capabilities compared with those derived from young rats. The cells from aged rats showed significantly increased cell attachment and the expression of osteoblastic function on photofunctionalized titanium than on untreated titanium. In addition, the strength of osseointegration was increased by 40% in aged rats carrying the photofunctionalized implants. Robust bone formation was observed around the photofunctionalized implants with strong elemental peaks of calcium and phosphorus, whereas the tissue around untreated implants showed weaker calcium and phosphate signals than titanium ones. CONCLUSION: These in vivo and in vitro results corroboratively demonstrate that photofunctionalization is effective for enhancing osseointegration in aged rats.

Biocompatibility of 4-META/MMA-TBB resin used as a dental luting agent.

STATEMENT OF PROBLEM: The bonding and biological properties of currently used luting/cementing materials need to be improved. 4-Acryloyloxyethyl trimellitate anhydride/methyl methacrylate-tri-n-butylborane (4-META/MMA-TBB) resin is primarily used for splinting mobile teeth or treating fractured teeth. It undergoes moisture-resistant polymerization and bonds strongly to dentin and metals. PURPOSE: The purpose of this in vitro study was to compare the biological and biochemical properties META/MMA-TBB resin with those of conventional polymethyl methacrylate (PMMA)-MMA resin and other currently used luting materials in order to determine whether it may be a viable dental luting agent. MATERIAL AND METHODS: The degree of polymerization of 4-META/MMA-TBB resin, PMMA-MMA autopolymerizing resin, 10-methacryloyloxydecyl dihydrogen phosphate-dimethacrylate (MDP-DMA) adhesive resin, and a glass ionomer cement was measured by Fourier-transformed infrared spectroscopy. Free radical production during setting was evaluated by electron spin resonance (ESR) spectroscopy. Rat dental pulp cells cultured on these materials were examined for cell viability, attachment, proliferation, and functional phenotype. RESULTS: The degree of polymerization of 4-META/MMA-TBB resin was 82% thirty minutes after preparation, compared to 66% for PMMA-MMA autopolymerizing resin. ESR spectroscopy revealed free radical production from 4-META/MMA-TBB resin and glass ionomer cement was equivalent 24 hours after preparation, with no spike in radical generation observed. In contrast, free radical production from PMMA-MMA and MDP-DMA adhesive resins was rapid and sustained and 10 to 20 times greater than that from 4-META/MMA-TBB. The percentage of viable dental pulp cells 24 hours after seeding was considerably higher on MDP-DMA and 4-META/MMA-TBB resin than on glass ionomer cement. Cell number, proliferation, and alkaline phosphatase activity were highest on 4-META/MMA-TBB resin and lowest on the glass ionomer cement. CONCLUSIONS: 4-META/MMA-TBB resin is at least as biocompatible, and perhaps even more biocompatible, than other current luting materials, with fast, favorable, and nontoxic polymerization properties. Further in vivo and human studies of 4-META/MMA-TBB resin as a dental luting agent are warranted.

Ultraviolet photofunctionalization increases removal torque values and horizontal stability of orthodontic miniscrews.

INTRODUCTION: The objective of this study was to examine the effects of ultraviolet-mediated photofunctionalization of miniscrews and the in-vivo potential of bone-miniscrew integration. METHODS: Self-drilling orthodontic miniscrews made from a titanium alloy were placed in rat femurs. Photofunctionalization was performed by treating the miniscrews with ultraviolet light for 12 minutes with a photo device immediately before implantation. Maximum insertion torque (week 0), removal torque (weeks 0 and 3), and resistance to lateral tipping force (week 3) were examined. RESULTS: The removal torque at 3 weeks of healing was higher for the photofunctionalized screws than for the untreated screws. The regenerated bone tissue was more intact and contiguous around the photofunctionalized miniscrews than around the untreated ones. The miniscrew-bone complex seemed to produce interface failure, not cohesive fracture, in both groups. The displacement of untreated screws under a lateral tipping force was greater than that of photofunctionalized miniscrews. CONCLUSIONS: These results suggest that photofunctionalization increases the bioactivity of titanium-alloy miniscrews and improves the anchoring capability of orthodontic miniscrews, even without modification of the surface topography.

Nanofeatured surfaces in dental implants: contemporary insights and impending challenges.

Dental implant therapy, established as standard-of-care nearly three decades ago with the advent of microrough titanium surfaces, revolutionized clinical outcomes through enhanced osseointegration. However, despite this pivotal advancement, challenges persist, including prolonged healing times, restricted clinical indications, plateauing success rates, and a notable incidence of peri-implantitis. This review explores the biological merits and constraints of microrough surfaces and evaluates the current landscape of nanofeatured dental implant surfaces, aiming to illuminate strategies for addressing existing impediments in implant therapy. Currently available nanofeatured dental implants incorporated nano-structures onto their predecessor microrough surfaces. While nanofeature integration into microrough surfaces demonstrates potential for enhancing early-stage osseointegration, it falls short of surpassing its predecessors in terms of osseointegration capacity. This discrepancy may be attributed, in part, to the inherent "dichotomy kinetics" of osteoblasts, wherein increased surface roughness by nanofeatures enhances osteoblast differentiation but concomitantly impedes cell attachment and proliferation. We also showcase a controllable, hybrid micro-nano titanium model surface and contrast it with commercially-available nanofeatured surfaces. Unlike the commercial nanofeatured surfaces, the controllable micro-nano hybrid surface exhibits superior potential for enhancing both cell differentiation and proliferation. Hence, present nanofeatured dental implants represent an evolutionary step from conventional microrough implants, yet they presently lack transformative capacity to surmount existing limitations. Further research and development endeavors are imperative to devise optimized surfaces rooted in fundamental science, thereby propelling technological progress in the field.

Inhibition of pentylenetetrazole-induced seizure in mice by using a 4 Hz magnetic field: a comparative study with a 60 Hz magnetic field.

We investigated the comparative effects of 4 and 60 Hz magnetic fields on pentylenetetrazole (PTZ)-induced seizure in mice. For this study, we measured the latent time to seizure, seizure duration, and lethality induced by PTZ in mice exposed to 4 and 60 Hz magnetic fields (MF) for 30 min. Compared to sham-exposed controls, the latent time to tail twitching and seizure in the 4 Hz MF group was significantly decreased while the latent time to seizure in the 60 Hz MF group was significantly increased. The seizure duration in the 4 Hz MF group was significantly decreased while that in the 60 Hz MF group was significantly increased. More importantly, while the mice exposed to a 60 Hz MF experienced significantly increased lethality after seizure convulsion, those exposed to a 4 Hz MF showed no lethality, with a shortening of the duration of seizure. This beneficial effect of a 4 Hz MF on seizure has the same implication as the anti-oxidative effects of a 4 Hz MF observed in our previous work. The results of our current and previous works indicate that a 4 Hz MF may be used as a therapeutic physical agent for the treatment of oxidative stress-induced diseases, including seizure, with or without chemical drugs.

A Novel Cell Delivery System Exploiting Synergy between Fresh Titanium and Fibronectin.

Delivering and retaining cells in areas of interest is an ongoing challenge in tissue engineering. Here we introduce a novel approach to fabricate osteoblast-loaded titanium suitable for cell delivery for bone integration, regeneration, and engineering. We hypothesized that titanium age influences the efficiency of protein adsorption and cell loading onto titanium surfaces. Fresh (newly machined) and 1-month-old (aged) commercial grade 4 titanium disks were prepared. Fresh titanium surfaces were hydrophilic, whereas aged surfaces were hydrophobic. Twice the amount of type 1 collagen and fibronectin adsorbed to fresh titanium surfaces than aged titanium surfaces after a short incubation period of three hours, and 2.5-times more fibronectin than collagen adsorbed regardless of titanium age. Rat bone marrow-derived osteoblasts were incubated on protein-adsorbed titanium surfaces for three hours, and osteoblast loading was most efficient on fresh titanium adsorbed with fibronectin. The number of osteoblasts loaded using this synergy between fresh titanium and fibronectin was nine times greater than that on aged titanium with no protein adsorption. The loaded cells were confirmed to be firmly attached and functional. The number of loaded cells was strongly correlated with the amount of protein adsorbed regardless of the protein type, with fibronectin simply more efficiently adsorbed on titanium surfaces than collagen. The role of surface hydrophilicity of fresh titanium surfaces in increasing protein adsorption or cell loading was unclear. The hydrophilicity of protein-adsorbed titanium increased with the amount of protein but was not the primary determinant of cell loading. In conclusion, the osteoblast loading efficiency was dependent on the age of the titanium and the amount of protein adsorption. In addition, the efficiency of protein adsorption was specific to the protein, with fibronectin being much more efficient than collagen. This is a novel strategy to effectively deliver osteoblasts ex vivo and in vivo using titanium as a vehicle.

How about an Educational Framework for Nursing Staff in Long-Term Care Facilities to Improve the Care of Behavioral and Psychological Symptoms of Dementia?

Behavioral and psychological symptoms of dementia (BPSD) are common in residents of long-term care facilities (LTCFs). In LTCFs, nursing staff, including nurses and care workers, play a crucial role in managing BPSD as those most in contact with the residents. However, it is ambiguous where their focus should be for effective BPSD care. Thus, this paper aims to reveal BPSD care competencies for nursing staff in LTCFs and to outline an initial frame of education. A multiphase mixed-methods approach, which was conducted through topic modeling, qualitative interviews, and a Delphi survey, was used. From the results, a preliminary educational framework for nursing staff with categories of BPSD care competence was outlined with the four categories of BPSD care competence: using knowledge for assessment and monitoring the status of residents, individualizing approaches on how to understand residents and address BPSD, building relationships for shared decision-making, and securing a safe environment for residents and staff in LTCFs. This preliminary framework illuminates specific domains that need to be developed for competent BPSD care in LTCFs that are centered on nursing staff who directly assess and monitor the changing and deteriorating state of residents in LTCFs.