Long-Term Taste Impairment after Intensity-Modulated Radiotherapy to Treat Head-and-Neck Cancer: Correlations with Glossectomy and the Mean Radiation Dose to the Oral Cavity.

We explored the effects of various parameters on taste impairments (TIs) in head-and-neck (H&N) cancer patients receiving intensity-modulated radiotherapy (IMRT). From January 2014 to September 2017, 88 H&N cancer patients subjected to curative or postoperative IMRT were enrolled in this prospective study. All patients underwent at least 1 year of follow-up after IMRT. Quality-of-life assessments in terms of patient-reported gustatory function were measured using the taste-related questions of the European Organization for Research and Treatment of Cancer H&N35 questionnaires. At a median follow-up time of 27 months, 27 of 88 patients (30.7%) reported long-term TIs. In multivariate analyses, glossectomy most significantly predicted TIs (P = 0.04). The percentage of TIs (61.5%) was significantly (P = 0.03) higher in patients who underwent partial or total glossectomy than in patients who did not undergo surgery (28.0%) and those who underwent radical surgery without glossectomy (20.0%). When we excluded surgical patients from analyses, the mean radiation dose to the oral cavity was of borderline significance in terms of TI prediction (P = 0.05). Only 10.5% of patients suffered from TIs when the mean radiation dose was <5000 cGy compared with 38.7% when the mean dose was ≥5000 cGy. In conclusion, glossectomy is the major cause of long-term TIs in H&N cancer patients receiving IMRT. In patients who do not undergo glossectomy, reduction of the mean radiation dose to the oral cavity may reduce TIs after IMRT.

Comparison and preparation of multilayered polylactic acid fabric strengthen calcium phosphate-based bone substitutes for orthopedic applications.

An attempt to maintain the three-dimensional space into restorative sites through the conveniently pack porous fillers are general used strategy. Advancement in the manufacturing protective shells in the scaffolds, which would be filled with brittle ceramic grafts for the development of highly connective pores provides the approach to solve crack problem for generating the tissues. Therefore, multilayered braided and alkalized poly(lactic acid) (PLA) composites with calcium phosphate bone cement (CPC) were synthesized and compared. The PLA/CPC composites were divided into various groups according to a series of heat-treatment temperatures (100-190 °C) and periods (1-3 h) and then characterized. The effects of 24-h immersion on the strength decay resistance of the samples were compared. Results showed that the residual oil capped on the surfaces of alkalized PLA braid was removed, and the structure was unaltered. However, the reduced tensile stress of alkalized PLA braids was due to ester-group formation by hydrolysis. Mechanical test results of PLA/CPC composites showed that the strength significantly increased after heat treatment, except when the heating temperature was higher than the PLA melting point at approximately 160-170 °C. The degree of PLA after recrystallization became higher than that of unheated composites, thereby leading to reduced strength and toughness of the specimen. Braiding fibers of biodegradable PLA reinforced and toughened the structure particularly of the extra-brittle material of thin-sheet CPC after implantation.

Effects of Ti surface treatments with silane and arginylglycylaspartic acid peptide on bone cell progenitors.

Achieving optimal aesthetic appearance is a major objective in dental implant design, and the interaction between the materials and the bone cell progenitors is an important factor in the attainment of this objective. In this study, a novel concept was evaluated by varying the surface modifications on titanium (Ti). Different levels of roughness can be attained by machine grinding (M), sand blasting, and acid etching (SLA) of the samples. The behavior of bone cell progenitors (D1) on the surfaces of Ti disks with different surface modifications was investigated. The surfaces of M or SLA disks were silanized (MS or SLAS group) through treatment with silane/Gly-Arg-Gly-Asp-Ser (GRGDS) peptide (MSP or SLASP group) and anchored particles of tetracalcium phosphate (TTCP) on the specimen surfaces (SLA-TTCP group). Physicochemical analysis was performed by metallographic microscopy, scanning electron microscopy, and contact angle analysis. The proliferation and the quantitative alkaline phosphatase (ALP) production of D1 cells on the surface of different sample groups were determined. The SLASP group had a significantly larger D1 cell proliferation than the other groups after 4 and 7 d of incubation (p < 0.05). ALP expression was a very early marker of differentiation, and was the first indication of the increasing number of cells at 7 d of culture. Among the groups in the M substrate series (i.e., M, MS, and MSP) and in the SLA series (i.e., SLA, SLAS, and SLASP), the MSP and SLASP specimens exhibited superior differentiation abilities on respective cultures until day 7 and day 10. A high number of hydrophilic surfaces dominated cell proliferation in the early stage of cell attachment. However, factors affecting the pore structure and the surface morphology can improve cell proliferation and differentiation. According to analyses of proliferation and ALP expression of bone cell progenitors D1, the original SLA implant surface can be improved with surface treatment methods, such as silanization and treatment with graft GRGDS pentapeptide. These methods can be potential candidates for the promotion of bone growth.

Color stability of nanocrystallite-treated and silicate-treated fillers of calcium phosphate composite resin: an in vitro study.

STATEMENT OF PROBLEM: Some composite resins fail esthetically because the color differences to adjacent tooth structure are more than the limits of color tolerance (values are higher than 3.3 ΔE units). PURPOSE: The purpose of this study was to assess the effect on color stability of surface-modified dicalcium phosphate anhydrous particles treated with nanocrystallites and silane coupling agents used as fillers for dental composite resin. MATERIAL AND METHODS: Specimens were divided into 4 groups of fillers on unmodified (without modification) and on modified surfaces (silanization, nanocrystallites, and nanocrystallites with silica). These groups served as reinforcements and had 2 mass ratios of fillers (filler+resin) at 30% and 50%. The color differences were measured from day 1 after thermocycling procedures and for different specimen-treated procedures (drying, immersion, and thermocycling) at 1 to 16 days after 24 hours of immersion (n=5). ANOVA test was used to analyze the differences. The Student t test was used to evaluate the significant group comparisons, and a 3-way ANOVA was used to determine differences and interactions with the filler amount data (α=.05). RESULTS: Specimens with lower amounts of silica-treated fillers exhibited more variations in color than specimens with larger amounts of fillers. The main color variation was observed within the dried specimens after 24 hours of immersion. The color difference stabilized within 8 days. Fewer changes in the ΔE values were noted in the groups of filler surfaces with nanocrystallites than in groups without nanocrystallized treatment after the 1 day to 16 days of aging. CONCLUSIONS: Color difference was significantly reduced when the fillers reached a certain proportion, which further indicated that fillers with nanocrystal treatment could stabilize color variations within perceptible color tolerances (2.0 ΔE units) after immersion and thermocycling.

Survival-weighted quality of life profiles in patients treated for laryngeal and hypopharyngeal cancers.

Objectives: This study assessed functional outcomes and quality of life (QoL) in the long term in individuals treated for laryngohypopharyngeal cancer (LHC) by estimating their life expectancy (LE), survival-weighted psychometric scores (SWPSs), and quality-adjusted LE (QALE). Materials and methods: To estimate survival outcomes, we retrospectively reviewed the data of 1576 patients treated for primary LHC between January 2010 and December 2018 and followed them until death or December 2020. We also prospectively collected QoL and functional data between October 2013 and November 2022 from 232 patients by administering the Taiwanese Chinese versions of the QoL Questionnaire Core 30, Head and Neck 35, and EQ-5D-3L. To estimate LE, we employed linear extrapolation of a logit-transformed curve. We calculated QALE and SWPSs by combining the QoL data with the LE results. Results: We estimated the LE of the patients with LHC to be 7.8 years and their loss of LE to be 15.7 years. The estimated QALE was 7.0 QALYs, with a loss of QALE of 16.5 QALYs. Lifetime impairment durations were estimated for cognitive (4.9 years), physical (4.2 years), emotional (3.4 years), social (3.4 years), and role functions (2.7 years). We estimated the durations of problems related to swallowing, speech, and teeth to be 6.2, 5.6, and 4.8 years, respectively. The patients were expected to be dependent on feeding tubes for 1.2 years. Conclusions: Patients with LHC experience significant reductions in both LE and QALE. SWPSs may constitute a valuable tool for obtaining subjective information regarding how LHC affects multifaceted QoL outcomes.

Preliminary comparison of the remineralization and desensitization effects of a novel mineralized ion-releasing toothpaste and commercially available competitive products.

Background/purpose: Toothpaste plays an important role in brushing teeth to maintain oral hygiene and health. The purpose of this study was to develop a new toothpaste containing surface nanocrystal-rich dicalcium phosphate anhydrous (DCPA) powder and to investigate its effect on tooth samples. Materials and methods: The innovative toothpaste (REALCaP®/Group R) was compared with two commercial toothpastes (BioRepair®/Group B and Sensodyne®/Group S). Brushing cycle tests were performed on bovine tooth slices coated with individual toothpaste and a control group without toothpaste (Group C). Microhardness, roughness, surface structure observation, and X-ray diffraction (XRD) were performed on cycle days 4, 7, and 14 to analyze the impact of the toothpastes on tooth samples. Reults: Microhardness in the Group R was higher than that of the other groups regardless of the cycle days. Roughness in the Group R increased on days 4 and 7 but decreased on day 14. Roughness in the groups S and B increased with days. Microstructural observation revealed that most exposed dentinal tubules had been sealed in the Group R on day 14. Overlay thickness in the Group R was significantly higher than that in the groups S and B on days 4, 7, and 14. XRD analysis showed no hydroxyapatite (HA) peak in the Group S. The HA peak in the Group R was higher than that in the Group B on day 14. Conclusion: The innovative toothpaste has better properties than the commercially available products in terms of microhardness, roughness, and effectiveness in sealing dentinal tubules.

In vitro evaluation of electrospun polyvinylidene fluoride hybrid nanoparticles as direct piezoelectric membranes for guided bone regeneration.

A polyvinylidene fluoride (PVDF) piezoelectric membrane containing carbon nanotubes (CNTs) and graphene oxide (GO) additives was prepared, with special emphasis on the piezoelectric activity of the aligned fibers. Fibroblast viability on membranes was measured to study cytotoxicity. Osteoprogenitor D1 cells were cultured, and mineralization of piezoelectric composite membranes was assessed by ultrasound stimulation. Results showed that the electrospun microstructures were anisotropically aligned fibers. As the GO content increased to 1.0 wt% (0.2 wt% interval), the ß phase in PVDF slightly increased but showed the opposite trend with the increase in CNT. Excessive addition of GO and CNT hindered the growth of the ß phase in PVDF. The direct piezoelectric activity and mechanical properties showed the same trend as the ß phase in PVDF. Moreover, GO/PVDF with the same nanoparticle content showed better performance than CNT/PVDF composites. In this study, a comparison of the generated piezoelectric specific voltage (unit: 10-3 Vg-1 cm-2, linear stretch, g33) with control PVDF only (0.55 ± 0.16) revealed that the two composites containing 0.8 wt% GO- and 0.2 wt% CNT- with 15 wt% PVDF exhibited excellent piezoelectric voltages, which were 3.37 ± 1.05 and 1.45 ± 0.07 (10-3 Vg-1 cm-2), respectively. In vitro cultures of these two groups in contact with D1 cells showed significantly higher alkaline phosphatase secretion than the PVDF only group within 1-10 days of cell culture. Further application of ultrasound stimulation showed that the piezoelectric membrane differentiated D1 cells earlier than without ultrasound and induced higher proliferation and mineralization. This developing piezoelectric effect is expected to generate voltage through activities to enhance microcurrent stimulation in vivo.

Postoperative radiotherapy alone is as effective as postoperative chemoradiotherapy in patients with pT4aN0 gingival cancer with negative surgical margins.

Background and purpose: This study compared the survival outcomes following postoperative chemoradiotherapy (CCRT) and postoperative radiotherapy (RT) alone for patients with gingival cancer with negative surgical margins and only bone invasion. Materials and methods: Of the 2579 gingival cancer cases reviewed from 2002 to 2018, 156 were enrolled in the study (CCRT: 63 patients; RT: 93 patients). The primary endpoints were the impact of adjuvant treatment (RT vs. CCRT) on overall survival (OS), locoregional recurrence-free survival (LRRFS), and distant metastasis-free survival (DMFS). Subgroup analyses were conducted based on surgical margins (<5 mm vs. ≥ 5 mm) and different adjuvant treatments (RT vs. CCRT). Results: Median follow-up time, age, and invasion depth were 88.5 months, 57 years, and 14 mm, respectively. More patients undergoing adjuvant CCRT had surgical margins < 5 mm (47.6% vs. 21.5%, p < 0.01) than those undergoing RT. No significant difference was observed in the 5-year OS, LRRFS, and DMFS of patients undergoing adjuvant RT and CCRT. Although adjuvant RT alone and CCRT provided similar local control for patients with surgical margins ≥ 5 mm, worse LRRFS trends were observed in patients with surgical margins < 5 mm (hazards ratio, 6.15, 95% confidence interval 0.92-41.13, p = 0.06). Conclusion: Postoperative RT alone may be effective for patients with gingival cancer with negative surgical margins (≥5 mm) and only bone invasion, while postoperative CCRT may result in better LRRFS than RT alone for patients with surgical margins < 5 mm.

Synergistic effect of drug/antibiotic-impregnated micro/nanohybrid mesoporous bioactive glass/calcium phosphate composite bone cement on antibacterial and osteoconductive activities.

Calcium phosphate bone cements (CPC) can be used in minimally invasive surgery because of their injectability, and they can also be used to repair small and irregular bone defects. This study aimed to release the antibiotic gentamicin sulfate (Genta) to reduce tissue inflammation and prevent infection in the early stages of bone recovery. Subsequently, the sustained release of the bone-promoting drug ferulic acid (FA) mimicked the response of osteoprogenitor D1 cells interaction, thereby accelerating the healing process of the overall bone repair. Accordingly, the different particle properties of micro-nano hybrid mesoporous bioactive glass (MBG), namely, micro-sized MBG (mMBG) and nano-sized MBG (nMBG), were explored separately to generate different dose releases in MBG/CPC composite bone cement. Results show that nMBG had better sustained-release ability than mMBG when impregnated with the same dose. When 10 wt% of mMBG hybrid nMBG and composite CPC were used, the amount of MBG slightly shortened the working/setting time and lowered the strength but did not hinder the biocompatibility, injectability, anti-disintegration, and phase transformation of the composite bone cement. Furthermore, compared with 2.5wt%Genta@mMBG/7.5 wt% FA@nMBG/CPC, 5wt.%Genta@mMBG/5wt.%FA@nMBG/CPC exhibited better antibacterial activity, better compressive strength, stronger mineralization of osteoprogenitor cell, and similar 14-day slow-release trend of FA. The MBG/CPC composite bone cement developed can be used in clinical surgery to achieve the synergistic sustained release of antibacterial and osteoconductive activities.

Immediate implant placement with and without provisionalization: A comparison of a one-year longitudinal study.

Background/purpose: Immediate implant placement (IIP) with and without immediate provisionalization (Ipro) may yield satisfactory results in appropriate indications and treatment, especially in the esthetic zone. The aim of this study was to compare implant stability, marginal bone loss (MBL), survival rates, and patient satisfaction between IIP with Ipro and IIP without Ipro. Materials and methods: Seventy patients, each with a failed maxillary anterior tooth, were randomly assigned to IIP with Ipro (Group A: n = 35) or IIP without Ipro (Group B: n = 35). Implant stability quotient (ISQ) and standardized periapical radiographs were performed at surgery and at 3, 6, 9, and 12 months postoperatively to investigate implant stability and MBL, respectively. Survival was assessed 1 year after surgery. Patient satisfaction was evaluated with a visual analogue scale (VAS). Results: Primary ISQ and MBL were not significantly different between groups A and B immediately after surgery (P ＞ 0.05). Implant survival was 100% in both groups, and only one mechanical complication was observed. Patient satisfaction was good at definitive crown delivery and postoperatively 1-year in both groups. However, the immediate postoperative VAS score in Group A was significantly higher than that in Group B (P < 0.05). Conclusion: Group A revealed significantly higher secondary ISQ than Group B at postoperatively 3, 6, 9, and 12 months. There were no significant differences between groups A and B in terms of MBL and survival. Notably, patient satisfaction in Group A was significantly higher than in Group B immediately after surgery.