Hybrid Resorbable 3D-Printed Mesh/Electrospun Nanofibrous Drug/Biomolecule-Eluting Mats for Alveolar Ridge Preservation.

In this research study, we developed hybrid resorbable three-dimensional (3D)-printed mesh/electrospun nanofibrous biomolecule-eluting mats for alveolar ridge preservation. The fabrication process involved the use of 3D printing and coaxial electrospinning technologies. Specifically, we utilized a lab-developed solution-extrusion 3D printer to fabricate polycaprolactone (PCL) meshes. Then, bi-layered poly(lactic-co-glycolic acid) (PLGA) nanofibrous membranes, which embedded ibuprofen and epidermal growth factor (EGF), were prepared utilizing electrospinning and coaxial electrospinning techniques, respectively. To ensure the quality of the produced mesh and spun nanofibers, we carried out a characterization process. Furthermore, we estimated the in vitro and in vivo release characteristics of ibuprofen and EGF, respectively, using high-performance liquid chromatography and enzyme-linked immunosorbent assays. In addition, we assessed the effectiveness of hybrid nanofibrous mats for preserving the alveolar ridge by adopting an animal model and conducting a histology examination. The study findings demonstrate that the nanofibrous mats provided a continuous discharge of ibuprofen and EGF for more than four weeks. Moreover, the animal test carried out in vivo showed that animals implanted with this combination of mesh and drug-eluting mats displayed considerably greater mobility than those without mats. The histological analysis revealed no unfavorable impacts from the drug-eluting mats. Our study demonstrated the successful fabrication of resorbable drug-eluting nanofibrous mats for alveolar ridge preservation by utilizing both 3D printing and coaxial electrospinning technologies.

The correspondence of 3D supporting bone loss and crown-to-root ratio to periodontitis classification.

AIM: Assessing the application of three-dimensional clinical attachment loss (3D-CAL), 3D supporting bone loss (3D-SBL), supracrestal tissue attachment (STA), and crown-to-root ratio (CRR) in evaluating the 2017 periodontitis classification. MATERIALS AND METHODS: We analysed ninety single-rooted human premolars with micro-computed tomography. The amount of 3D-SBL, linear radiographic bone loss (RBL), and CRR corresponding to various periodontitis stages as well as the statistical significance was investigated. RESULTS: From a 3D perspective, the premolars with a 21% of 3D-SBL at 2.0 mm coronal root length (RL) and 15% RBL corresponded to the periodontitis stage I. Premolars with a 44% of 3D-SBL at coronal 4.2-4.4 mm RL and 33% RBL accorded with the periodontitis stage II. Excluding the consideration of STA, CRR = 5:6 and 4:3 were associated with the levels at 15% and 33% RBL, respectively. CONCLUSIONS: A greater percentage of 3D-CAL than that of 2D-CAL is significant at evaluated levels. It is feasible to correlate the 3D-SBL, 3D-CAL, and STA parameters to evaluate the stages of periodontitis severity. However, the current use of RBL and CAL as applied for staging in the 2017 classification might be inconsistent with the evaluated premolar roots length, when STA dimensions are considered.

Structural evolution of in situ boron-doped SiGe ultrathin film analyzed by multi-optical methods.

In situ boron (B)-doped SiGe (BSG) layer is extensively used in the source (S)/(D) drain of metal-oxide-semiconductor field-effect transistors. An unexpected structural evolution occurs in BSG during metallization and activation annealing during actual fabrication, which involves a correlated interaction between B and SiGe. Herein, the complicated phenomena of the structural evolution of BSG were analyzed by 325 nm micro-Raman spectroscopy, x-ray photoelectron spectroscopy (XPS), reflective second harmonic generation (RSHG), and synchrotron x-ray diffraction (XRD). Optical inspection was integrated into these processes to establish a multi-optical method. 325 nm micro-Raman spectroscopy was used to determine variations in Si-Si, Si-Ge, and Ge-Ge bonds in BSG. XPS exhibited the binding energy evolution of Ge3d during different annealing processes at varied Ge ratios and B concentrations. RSHG revealed the polar Si-B and Ge-B bonds formed during annealing. Synchrotron XRD provided the structure and strain changes of BSG. Secondary-ion mass spectrometer profiles provided the species distribution, which was used to examine the results of multi-optical method. Furthermore, double-layered BSG (DBSG) with different B concentrations were analyzed using the multi-optical method. Results revealed that Ge aggregated in the homogeneous interface of DBSG, and that B dopants in BSG served as carrier providers that strongly influenced the BSG structure. However, BSG with excessive B concentration was unstable and increased the B content (SiB3) through metallization. For BSG with a suitable B concentration, the formation of Si-B and Ge-B bonds suppressed the diffusion of Ge from SiGe, thereby reducing the possibility of Ge loss and further B pipe-up in the heavily doped S/D region.

A paradigm for evaluation and management of the maxillary sinus before dental implantation.

OBJECTIVES: To determine a paradigm for evaluating and managing maxillary sinus conditions before dental implantation via preoperative sinonasal assessment. STUDY DESIGN: Prospective cohort study. METHODS: Eighty-four patients who underwent dental implantation with or without sinus augmentation were included. Maxillary sinus conditions were classified into groups 1 to 6 according to cone-beam computed tomography (CT) findings: 1) nonspecific findings, 2) solitary polyp or cyst, 3) mucosal thickening, 4) air-fluid level or fluid accumulation, 5) near-total opacification of the maxillary or other paranasal sinus, and 6) calcification spots in the maxillary sinus. Dental implantation with or without sinus augmentation was suggested with postoperative sinus observation (groups 1-3), after medication for acute sinusitis (group 4), and after comprehensive treatment of chronic or fungal sinusitis (groups 5-6). Intraoperative and postoperative sinus-related complications were recorded. RESULTS: Two patients (groups 1 and 3) developed acute rhinosinusitis after sinus augmentation; both recovered completely with medical treatment. Schneiderian membrane perforation occurred during sinus lift surgery in six patients (group 1): five recovered after conservative medical therapy and close observation, whereas one required endoscopic sinus surgery and recovered well. No chronic rhinosinusitis developed after dental implantation. CONCLUSION: Craniofacial CT is crucial for pre-dental implantation sinonasal evaluation. The risk of dental implant-related chronic rhinosinusitis is low for patients with cysts, polyps, or mucosal thickening in the maxillary sinus. However, preventive endoscopic sinus surgery is recommended for patients with incurable chronic rhinosinusitis, fungal sinusitis, and large polyps or cysts. LEVEL OF EVIDENCE: 4. Laryngoscope, 128:1261-1267, 2018.

The chemical states and atomic structure evolution of ultralow-energy high-dose Boron implanted Si(110) via laser annealing.

Further scale down the dimension of silicon-based integrated circuit is a crucial trend in semiconductor fabrication. One of the most critical issues in the nano-device fabrication is to confirm the atomic structure evolution of the ultrathin shallow junction. In this report, UV Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), X-ray absorption near edge structure (XANES) and reflective second harmonic generation (RSHG) are utilized to monitor the pulse laser induced atomic structure evolution of ultralow-energy high-dose Boron implanted Si(110) at room and cold substrate temperature. A peak feature around 480 cm-1 resolved in UV Raman spectra indicates the formation of Si-B bond after the laser irradiation. The red shift of binding energy of Si element (~99 eV) in XPS and the evolution of absorption peak (~196.2 eV) in XANES reveal that the changes in the chemical states of ultra shallow junction strongly correlate to the activation process of Boron implantation, which is confirmed by RSHG measurement. The substrate temperature effect in the recrystallization of Boron implanted region is also realized by cross-section high-resolution TEM (HRTEM). The phenomena of Si-B bond formation and ultra-shallow junction recrystallization can be traced and applied to improve the reliability of Si ultra shallow junction in the future.

Fabrication of Multi-Layered Lidocaine and Epinephrine-Eluting PLGA/Collagen Nanofibers: In Vitro and In Vivo Study.

This study developed multi-layered lidocaine- and epinephrine-eluting biodegradable poly[(d,l)-lactide-co-glyco lide] (PLGA)/collagen nanofibers. An electrospinning technique was employed to fabricate the multi-layer biodegradable drug-eluting nanofibers. After fabrication, the nanofibrous membranes were characterized. The drug release characteristics were also investigated. In addition, the in vivo efficacy of nanofibers for pain relief and hemostasis in palatal oral wounds of rabbits were evaluated. Histological examinations were also completed. The experimental results suggested that all nanofibers exhibited good biocompatibility and eluted effective levels of lidocaine and epinephrine at the initial stages of wound recovery.

Assessment of pain perception following periodontal and implant surgeries.

OBJECTIVE: To evaluate patients' pain perception following periodontal or implant surgery and to explore risk factors associated with post-surgical pain. MATERIALS AND METHODS: Patients undergoing periodontal or implant surgery were recruited. Post-surgical pain perception was evaluated by a numeric rating scale (NRS, 1-10) after 1 week. Self-reported durations of pain (DOP) and of swelling (DOS), and consumption of prescriptions were also recorded. Demographic and surgical variables were compared between the groups of mild (MP) and moderate-to-severe post-surgical pain (SP). Factors associated with SP were analysed statistically. RESULTS: Ten surgical types in three categories, comprising 330 surgeries in 253 patients, were included. Overall, 70.3% of the subjects experienced MP, 25.5% experienced moderate pain and 4.2% experienced severe pain. The highest median NRS score was found in subjects having advanced implant surgery [4.0, interquartile range (IQR) 4.00] and the lowest in open flap debridement surgery (1.0, IQR 1.00). The median DOP was 2.0 days (IQR 2.00). Analgesic need (median = 2.0 days, IQR 4.00) was correlated with the DOP (r = 0.406, p < 0.01) and the NRS score (r = 0.358, p < 0.01). Subjects receiving periodontal plastic surgery (OR = 3.20, 95% CI = 1.06-9.71), complex surgery (OR = 2.63, 95% CI = 1.31-5.25), increased surgical extension (OR = 1.78, 95% CI = 1.21-2.62) and increased anaesthesia (OR = 2.32, 95% CI = 1.13-4.76) were more likely to experience SP. CONCLUSIONS: The majority of patients perceived mild post-surgical pain, but the pain level varied among different surgical procedures. Periodontal plastic surgery, complex surgery, surgical extension and anaesthetic volume were associated with more pain.

Preclinical experiments on the release behavior of biodegradable nanofibrous multipharmaceutical membranes in a model of four-wall intrabony defect.

Guided tissue regeneration (GTR) therapy has been widely used to regenerate lost periodontium from periodontal disease. However, in terms of regenerative periodontal therapy, a multidrug-loaded biodegradable carrier can be even more promising in dealing with periodontal disease. In the current study, we fabricated biodegradable nanofibrous collagen membranes that were loaded with amoxicillin, metronidazole, and lidocaine by an electrospinning technique. The in vitro release behavior and the cytotoxicity of the membranes were investigated. A four-wall intrabony defect was created in rabbits for in vivo release analysis. The bioactivity of the released antibiotics was also examined. The experimental results showed that the drug-loaded collagen membranes could provide sustainable release of effective amoxicillin, metronidazole, and lidocaine for 28, 56, and 8 days, respectively, in vivo. Furthermore, the bioactivity of the released antibiotics remained high, with average bioactivities of 50.5% for amoxicillin against Staphylococcus aureus and 58.6% for metronidazole against Escherichia coli. The biodegradable nanofibrous multipharmaceutical membranes developed in this study may provide a promising solution for regenerative periodontal therapy.

In vitro and in vivo investigation of drug-eluting implants for the treatment of periodontal disease.

This paper developed solvent-free drug-eluting implants for metronidazole delivery for the treatment of periodontal disease and investigated the characteristics of the drug's release from the implants, both in vitro and in vivo, using an HPLC assay. The metronidazole exhibited a two-stage release behavior in vitro with an initial burst release followed by a diffusion-controlled release and then a secondary burst release. The accumulated drug release reached 100% on the 18th day, and the drug-eluting implant was totally dissolved on the same day. Additionally, the drug-eluting disks were implanted within the sub-gingival space of both lower incisors of six rabbits. The curve of in vivo drug release was smoother and showed a predominantly diffusion-controlled release. The implants were totally dissolved at 2 weeks after implantation. The concentration of metronidazole remained above the MIC(90) during the entire investigation.