The association between the severity of periodontitis and osteonecrosis of the jaw in patients with different cancer locations: a nationwide population-based study.

OBJECTIVES: To determine the relation between the severity of periodontitis and osteonecrosis of the jaw (ONJ) occurrence among different cancer locations and estimate the effect of dental care on ONJ prevention in cancer patients. MATERIALS AND METHODS: This population-based cross-sectional study was conducted through the Longitudinal Health Insurance Database, Taiwan. Patients with malignancies were collected and subdivided into groups according to their different cancer locations, the severity of periodontitis, and dental care. Multivariable logistic regression analysis was performed to assess the associations between ONJ and ONJ-related factors. RESULTS: A total of 8,234 ONJ patients and 32,912 control patients were investigated. Lip, oral cavity, and pharynx malignancies had the highest ONJ risk among all cancer locations (OR from 3.07 to 9.56, P < 0.01). There is a linear relationship between different severities of periodontitis and ONJ. Patients with radiotherapy and severe periodontitis had the highest ONJ risk (adjusted OR, 9.56; 95% CI, 5.34-17.1). Patients with good dental care had a lower ONJ risk. CONCLUSIONS: The periodontal condition and cancer location showed a significant impact on the risk of developing ONJ after adjusting for bisphosphonate use. Good dental care could decrease the risk of ONJ in cancer patients. The severity of periodontitis might be a target to predict the potency of ONJ. CLINICAL RELEVANCE: Dentists must be vigilant about the increased risk of ONJ in cancer patients with periodontitis, especially in the head and neck cancer population. Good dental care is advised for cancer patients with severe periodontitis.

The impact of timing and modalities of dental prophylaxis on the risk of 5-fluorouracil-related oral mucositis in patients with head and neck cancer: a nationwide population-based cohort study.

PURPOSE: This study investigated the impact of dental prophylaxis on 5-fluorouracil (5-FU)-related oral mucositis (OM) according to the head and neck cancer (HNC) locations and treatment times. METHODS: A total of 13,969 HNC participants, including 482 5-FU-related OM subjects and 13,487 comparisons were enrolled from the Longitudinal Health Insurance Database for Catastrophic Illness Patients of Taiwan between 2000 and 2008. All subjects were stratified into subgroups based on the times to perform chlorhexidine use, scaling, and fluoride application before 5-FU administration. The dental prophylaxis related to 5-FU-related OM was estimated by multiple logistic regression and represented with odds ratio (OR) and 95% confidence interval (CI). RESULTS: Fluoride gel application and scaling significantly impacted on OM development (p < 0.001), and the joint effect of fluoride gel and scaling induced 5-FU-related OM (OR = 3.46, 95% CI = 2.39-5.01). The risk of OM was raised 2.25-fold as scaling within 3 weeks before 5-FU-related chemotherapy (95% CI = 1.81-2.81), and a 3.22-fold increased risk of OM while fluoride gel was applied during 5-FU-related treatment (95% CI = 1.46-7.13). CONCLUSION: Dental prophylaxis significantly affected 5-FU-related OM in the HNC population. A short interval between dental scaling or fluoride application and 5-FU administration may be associated with higher prevalence of OM. Scaling simultaneously combined with chlorohexidine promoted 5-FU-related OM in specific HNC patients excluding the oral cancer and nasopharyngeal cancer population. Proper timing of the prophylactic dental treatments prior to 5-FU therapy could reduce the risk to develop 5-FU-related OM.

The association between dental therapy timelines and osteoradionecrosis: a nationwide population-based cohort study.

OBJECTIVES: The study aimed to investigate the timeline association with specific dental therapy and osteoradionecrosis (ORN) in oral cancer patients. MATERIALS AND METHODS: A total of 7394 oral cancer patients, including 198 ORN subjects, were retrieved from a Longitudinal Health Insurance Database for Catastrophic Illness Patients of Taiwan and were analyzed with the Cox proportional hazard regression to compare the ORN risk of individual dental treatments under different dental treatments. RESULTS: The initial dental treatment time significantly impacted on the risk of ORN in oral cancer patients (P<0.05). Pre-radiotherapy endodontic treatment and post-radiotherapy scaling or subgingival curettage increased ORN prevalence (hazard ratio [HR], 2.28 and 1.77, respectively). Endodontic treatment within 2 weeks to 1 month prior to radiotherapy increased the ORN risk by 5.83-fold. Dental scaling or subgingival curettage initialized from three to 6 months post-radiotherapy raised the ORN prevalence by 2.2-fold. Exodontia initialized within 2 weeks before radiotherapy (HR=1.49) or 1 to 3 months after radiotherapy (HR=2.63) greatly increased ORN prevalence. To perform oral surgery from 3 months pre-radiotherapy to 6 months after radiotherapy increased the 1.85-fold ORN risk. The chemotherapy combined oral surgery increased the ORN prevalence by 2.55-fold. CONCLUSIONS: Timing of dental treatment, including pre-radiotherapy endodontic treatment, post-radiotherapy scaling or subgingival curettage, and oral surgery or exodontia before and after radiotherapy, could closely relate to ORN development in oral cancer patients. CLINICAL RELEVANCE: Choosing right time to perform appropriate dental treatment could effectively reduce oral infection and ORN risk.

Prosthetic design related to peri-implant bone resorption in microvascular free fibular flap among patients with oral cancer: A retrospective clinical study.

STATEMENT OF PROBLEM: Prosthetic rehabilitation is challenging after tumor excision in patients with oral cancer. Prosthetic parameters may be compromised because of the physical limitations of the oral cavity. Although microvascular free fibular flaps are a common treatment modality for mandibular reconstruction and allow the placement of dental implants, fibular resorption under long-term functional loading is still a controversial issue. Research focusing on how prosthetic design affects fibular resorption around dental implants in an oral cancer population is lacking. PURPOSE: The purpose of this retrospective clinical study was to correlate the success of implant-supported prostheses in microvascular free fibular flaps with occlusal force and fibular resorption around the implants 7 years after functional loading. MATERIAL AND METHODS: The T-Scan III was used to measure occlusal force in 13 participants with oral cancer. Forty-seven successful endosseous dental implants (Biomet 3i) under functional loading in the participants from 2010 to 2017 were analyzed retrospectively. Prosthetic design including fibular length, rehabilitated arch length, and crown-to-implant ratios was estimated from panoramic radiographs. The intergonial distance was used to calibrate the panoramic radiographs to enhance accuracy. To compensate for panoramic distortion, all parameters were represented as a ratio such as fibular length/mandibular width; implant-supported prosthesis length/mandibular dental arch length; implant-supported prosthesis length/maxillary dental arch length; and mandibular dental arch length/maxillary dental arch length. A generalized estimating equation was used for longitudinal analysis to estimate the impact of variables on fibular resorption around the implants. RESULTS: Increased length of the implant-supported prostheses compared with maxillary and mandibular dental arch length significantly impaired the maximal occlusal force (P=.045 and P=.029). The crown-to-implant ratios in the fibular flaps were not correlated with fibular resorption around the implants under long-term functional occlusion (P>.05). The increased ratio of the implant-rehabilitated mandibular to maxillary dental arch length showed a statistically significant tendency to reduce fibular resorption around the implants (P=.007). CONCLUSIONS: Crown-to-implant ratios were not significantly correlated with maximal occlusal force or fibular resorption around dental implants. Increasing the length of the reconstructed mandibular implant-supported prosthesis in the fibular flap will reduce occlusal force. The rehabilitated mandibular dental length should be as long as the maxillary arch for optimum occlusal stress distribution to maintain the peri-implant fibula bone level.

The association with xerostomia from sialadenitis and the jaw osteonecrosis in head and neck cancer population: a nationwide cohort study.

OBJECTIVES: Determine the association between sialadenitis and osteonecrosis of the jaw (ONJ) in head and neck cancer (HNC) patients with varying severity of sialadenitis, treatment modalities, and cancer locations. MATERIALS AND METHODS: A total of 40,168 HNC patients, including 1907 ONJ subjects and 7559 matched comparisons, were enrolled from a Longitudinal Health Insurance Database for Catastrophic Illness Patients of Taiwan between 2000 and 2006. The association with sialadenitis and ONJ was estimated by logic regression and presented as the odds ratio (OR) and 95% confidence intervals (CIs). RESULTS: The occurrence of sialadenitis increased the risk of ONJ by 2.55-fold in HNC patients (95% CI = 2.20-2.95). The ONJ incidence was proportion to sialadenitis severity (OR = 2.53 to 4.43). Irradiated HNC patients had a higher tendency to develop jaw necrosis (osteoradionecrosis, ORN) (OR = 5.05, 95% CI = 4.39-5.80). When combined with irradiation exposure, sialadenitis significantly induced the occurrence of ORN (OR = 8.94, 95% CI = 7.40-10.8), especially in oral cancer patients (OR = 15.9 95% CI = 12.5-20.3). The risk of ONJ increased with radiotherapy dosage and duration, except for nasopharyngeal cancer (NPC) patients. CONCLUSIONS: There was a close association between sialadenitis and ONJ in the HNC population. The severity of sialadenitis was positive correlated to ONJ risk. Radiotherapy combined with sialadenitis significantly raised ORN incidence in HNC patients except for NPC patients. CLINICAL RELEVANCE: HNC patients complained that xerostomia from sialadenitis might increase the risk to develop ONJ, especially among those who received radiotherapy.

The impact of dental therapy timelines and irradiation dosages on osteoradionecrosis in oral cancer patients: A population-based cohort study.

OBJECTIVES: This study aimed to investigate how different timelines of various dental therapies were related to osteoradionecrosis development under consideration of radiotherapy dosage in patients with oral cancer. MATERIALS AND METHODS: A total of 7,107 oral cancer patients were enrolled, including 88 osteoradionecrosis patients treated with low radiotherapy dosages (<60 Gy) or high radiotherapy dosages (≥60 Gy), from the Longitudinal Health Insurance Database for Catastrophic Illness Patients of Taiwan. Cox proportional hazard regression was used to compare the osteoradionecrosis risk of various dental treatment timelines under different irradiation dosages. RESULTS: In the oral cancer population with low irradiation dosages (<60 Gy), performing periodontal therapy combined with irradiation significantly raised the risk of osteoradionecrosis by 2.21-fold. Starting radiotherapy within three months after dental surgery greatly increased the risk of developing osteoradionecrosis by 1.87-fold. The oral cancer patients treated with high radiation doses (≥60 Gy) receiving dental surgery within one month prior to radiotherapy had a significantly raised osteoradionecrosis occurrence by 1.60-fold. While the dental surgery was performed during the radiotherapy course, the risk of osteoradionecrosis was greatly increased by 2.21-fold. CONCLUSION: For oral cancer patients, performing dental surgery within three months before radiotherapy might significantly induce osteoradionecrosis. Patients that were treated with high irradiation dosages (≥60 Gy) had a higher tendency to develop osteoradionecrosis if they received dental surgery during radiotherapy. Those who were treated with low radiation dosages (<60 Gy) and received periodontal therapy during radiotherapy might have an increased risk in developing osteoradionecrosis.

The impact of occluding pairs on the chewing patterns among the elderly.

OBJECTIVES: This study aims to investigate the impact of occluding pairs (OPs) on chewing strokes, chewing time, mealtime duration, and bite force in an aging population. METHODS: The 100 participants included 52 women and 48 men with average age of 71.2 years. The subjects were restricted to those who can eat what they wanted and had no temporomandibular joint disorder (TMD) and dysphagia history; their OPs were counted in the posterior occlusal support zone in accordance with the Eichner classification. Free habitual mastication of a cornstarch cookie was analyzed by recording the number of chewing strokes and the amount of time needed for complete mastication. Strokes were counted by considering the opening and closing mandibular movements. Mealtime was defined as the time spent to finish a lunchbox and accomplish swallowing. Bite force was estimated with a T-Scan III®. A linear regression analysis was used to evaluate the impact of the OPs on the chewing strokes, chewing time, mealtime duration, and bite force. RESULTS: In this study, 76% of the participants had 4 OPs and 12% participants had 3 OPs. Increasing the OPs significantly shortened the chewing time and mealtime duration (P = 0.02). The mealtime duration did not notably affect the chewing time (P = 0.237). There was significant association between OPs and bite force (P < 0.0001). CONCLUSIONS: In elderly, increasing OPs significantly raised the bite force and shortened the chewing time and strokes. More OPs might be the key to maintain good chewing function. CLINICAL SIGNIFICANCE: Among the elderly, increasing OPs significantly raised the bite force and shortened the chewing time and mealtime duration. To provide better chewing function, good oral hygiene is important to maintain as many OPs as possible; how to gain more OPs is essential concern in the prosthodontic treatment plan making.

Solifenacin and tolterodine are equally effective in the treatment of overactive bladder symptoms.

BACKGROUND/PURPOSE: Various antimuscarinic agents have been developed for the treatment of overactive bladder (OAB). More data comparing these agents are still required. This study evaluated the efficacy and safety of solifenacin and tolterodine in Taiwanese patients with OAB symptoms. METHODS: This was a prospective, randomized, open-label study. A total of 75 patients (25 men and 50 women) with OAB symptoms were randomized to treatment with solifenacin (n = 39) or tolterodine (n = 36). Efficacy and safety variables were assessed and compared with the baseline and between the two groups. RESULTS: At week 12, solifenacin and tolterodine demonstrated equal efficacy in reducing the number of micturition (-2.56 ±3.31 vs. -2.44 ± 4.56, p = 0.58), urgency (-1.70 ± 3.07 vs. -1.15 ± 2.68, p =0.37) and incontinence (-2.79 ± 2.82 vs. -4.67 ± 9.29, p =0.28) episodes per 24 hours. There was no difference in improvement of the quality of life. The patient and physician assessments of treatment benefit were not statistically different for solifenacin and tolterodine (p = 0.23 and p = 0.52, respectively), with the majority showing benefits in both groups. The incidence of major adverse events, including dry mouth (18.0%vs. 8.3%, p = 0.31) and constipation (12.8%vs. 2.8%, p = 0.20) was not significantly different. Compared with baseline, the severity of dry mouth did not increase in either group. CONCLUSION: Both solifenacin and tolterodine are effective in treating key OAB symptoms, including urinary frequency, urgency and incontinence in the Taiwanese population. Both medications are comparably effective and safe, with the most common adverse effects being dry mouth and constipation.

A PEG-Based Hydrogel for Effective Wound Care Management.

It is extremely challenging to achieve strong adhesion in soft tissues while minimizing toxicity, tissue damage, and other side effects caused by wound sealing materials. In this study, flexible synthetic hydrogel sealants were prepared based on polyethylene glycol (PEG) materials. PEG is a synthetic material that is nontoxic and inert and, thus, suitable for use in medical products. We evaluated the in vitro biocompatibility tests of the dressings to assess cytotoxicity and irritation, sensitization, pyrogen toxicity, and systemic toxicity following the International Organization for Standardization 10993 standards and the in vivo effects of the hydrogel samples using Coloskin liquid bandages as control samples for potential in wound closure.

The association of variables of fibular reconstructed mandible and bite force in oral cancer patients with dental implant rehabilitation.

PURPOSE: The aim of this study was to investigate how the physical variables of fibular reconstructed mandibles with dental implants affects the relative bite force in oral cancer patients. MATERIALS AND METHODS: Over 7 years of follow-up, 13 oral cancer patients were enrolled who included 51 successful implants in the fibular flap. The tactile sensor analyzer evaluated the bite force. The crown-implant ratio, fibular, and rehabilitated dental length were measured using radiographic images. Linear regression was used to analyze the bite force related to the variables of the implants in the fibular reconstructed mandible. RESULTS: Even when the results showed no statistical significance (P > 0.05), increasing the crown-implant ratio, length of the fibular flap, and implant prosthetic reconstructed dentition had a tendency to decrease the bite force (estimate from -0.08% to -4.27%); there was a positive trend of occlusal force and the length of rehabilitative dentition compared with the dental antagonist (estimate = 6.95). CONCLUSION: In this study, the crown-implant ratio, implant dentition, and fibular flap length revealed no significant impact on the bite force or implant success in oral cancer patients; however, a trend to weaken the bite force was suggested once the numerical values of these variables increased.

Electrospun Polyacrylonitrile-Based Nanofibers Maintain Embryonic Stem Cell Stemness via TGF-Beta Signaling.

Embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) are capable of self-renewal and differentiation into any cell type, thus making them the focus of many clinical application studies. Culturing ESCs on mouse embryonic fibroblast-derived and cell-based feeder layers to maintain pluripotency is a standard laboratory procedure. However, xenogeneic contamination and the large amount of time required for feeder cell preparation are two challenges that encourage the use of a murine-based feeder layer. A novel biomaterial is required to replace the current cell-based feeder system. Toward this goal, we applied a combination of biocompatible polyacrylonitrile (PAN) and electrospinning technology to establish a non-cell-based feeder layer. According to results from stem cell marker staining, scanning electron microscopy, and embryoid body formation tests, optimal ESC stemness and pluripotency were noted in three electrospun groups (2, 4, and 8 minutes), with the longer electrospinning times producing higher feeder-layer densities. KEGG pathway microarray results identified TGF-beta signaling as one of the major deregulatory pathways on electrospun-based feeder layers. Western blot data indicate significant increases in TGF-beta receptor II, phosphorylated Smad3, and Nanog protein levels in the 4- and 8-minute electrospun-based feeder layer groups compared to the non-feeder layer group. Combined, the data suggest that electrospun-based feeder layers are good candidates for maintaining ESC and iPSC pluripotency in clinical applications.

The Impact of Oral Hygiene Maintenance on the Association Between Periodontitis and Osteoporosis: A Nationwide Population-Based Cross Sectional Study.

Both periodontitis and osteoporosis have similar sign of bone resorption in nature. However, the relationship of the severity between these 2 bone-loss diseases is still uncertain.The aim of this study was to investigate the association between the severity of osteoporosis and periodontitis regarding the impact of oral hygiene maintenance. In total, 35,127 osteoporosis patients and 50,498 comparisons were derived from the Longitudinal Health Insurance Database of Taiwan between 2000 and 2010. The population was subdivided into groups according to the different level oral hygiene maintenance and the severity of periodontitis and osteoporosis. The association between osteoporosis and periodontitis was estimated by multinomial logistic regression and rank correlation by Kendall rank correlation test, presented by odds ratio (OR), and 5% confidence intervals (CIs).After controlling the age, sex, and comorbidities, variables in the good oral hygiene maintenance population, we found that periodontitis raised 1.29-fold risk of osteoporosis (95% CI = 1.12-1.49); the risk of osteoporosis was increased with the elevated severity of periodontitis from 1.27 (95% CI = 1.08-1.48) to 1.38 (95% CI = 1.01-1.89). There is a positive correlation between the severity of periodontitis and osteoporosis occurrence in this population (OR = 1.27-1.46; Kendall rank correlation test P = 0.0003). In the poor oral hygiene maintenance population, periodontitis patients had 6.02-fold risk of osteoporosis than those who without periodontitis (95% CI = 4.65-7.81); the risk of osteoporosis was increased with periodontitis severity from 5.96 (95% CI = 4.48-7.92) to 6.37 (95% CI = 3.36-12.1).This result indicated the periodontitis and osteoporosis are conjunctive. The sudden periodontal breakdown of those who with good oral hygiene maintenance might be an indicator for the risk of osteoporosis; if those who were diagnosed as osteoporosis must pay more attention to their periodontal health. Good oral hygiene maintenance might be a crucial factor for preventing the deterioration of osteoporosis progressing; the oral hygiene maintenance plays a significant influence on the association between periodontitis and osteoporosis.

Differentiation of stem cells: strategies for modifying surface biomaterials.

Stem cells are a natural choice for cellular therapy because of their potential to differentiate into a variety of lineages, their capacity for self-renewal in the repair of damaged organs and tissues in vivo, and their ability to generate tissue constructs in vitro. Determining how to efficiently drive stem cell differentiation to a lineage of choice is critical for the success of cellular therapeutics. Many factors are involved in this process, the extracellular microenvironment playing a significant role in controlling cellular behavior. In recent years, researchers have focused on identifying a variety of biomaterials to provide a microenvironment that is conducive to stem cell growth and differentiation and that ultimately mimics the in vivo situation. Appropriate biomaterials support the cellular attachment, proliferation, and lineage-specific differentiation of stem cells. Tissue engineering approaches have been used to incorporate growth factors and morphogenetic factors-factors known to induce lineage commitment of stem cells-into cultures with scaffolding materials, including synthetic and naturally derived biomaterials. This review focuses on various strategies that have been used in stem cell expansion and examines modifications of natural and synthetic materials, as well as various culture conditions, for the maintenance and lineage-specific differentiation of embryonic and adult stem cells.