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Background Human platelet lysate (HPL) is emerging as the preferred xeno-free supplement for the expansion of mesenchymal stromal cells (MSCs) for bone tissue engineering (BTE) applications. Due to a growing demand, the need for standardization and scaling-up of HPL has been highlighted. However, the optimal storage time of the source material, i.e., outdated platelet concentrates (PCs), remains to be determined. The present study aimed to determine the optimal storage time of PCs in terms of the cytokine content and biological efficacy of HPL. Methods Donor-matched bone marrow (BMSCs) and adipose-derived MSCs (ASCs) expanded in HPL or fetal bovine serum (FBS) were characterized based on in vitro proliferation, immunophenotype, and multi-lineage differentiation. Osteogenic differentiation was assessed at early (gene expression), intermediate [alkaline phosphatase (ALP) activity], and terminal stages (mineralization). Using a multiplex immunoassay, the cytokine contents of HPLs produced from PCs stored for 1–9 months were screened and a preliminary threshold of 4 months was identified. Next, HPLs were produced from PCs stored for controlled durations of 0, 1, 2, 3, and 4 months, and their efficacy was compared in terms of cytokine content and BMSCs’ proliferation and osteogenic differentiation. Results BMSCs and ASCs in both HPL and FBS demonstrated a characteristic immunophenotype and multi-lineage differentiation; osteogenic differentiation of BMSCs and ASCs was significantly enhanced in HPL vs. FBS. Multiplex network analysis of HPL revealed several interacting growth factors, chemokines, and inflammatory cytokines. Notably, stem cell growth factor (SCGF) was detected in high concentrations. A majority of cytokines were elevated in HPLs produced from PCs stored for ≤ 4 months vs. > 4 months. However, no further differences in PC storage times between 0 and 4 months were identified in terms of HPLs’ cytokine content or their effects on the proliferation, ALP activity, and mineralization of BMSCs from multiple donors. Conclusions MSCs expanded in HPL demonstrate enhanced osteogenic differentiation, albeit with considerable donor variation. HPLs produced from outdated PCs stored for up to 4 months efficiently supported the proliferation and osteogenic differentiation of MSCs. These findings may facilitate the standardization and scaling-up of HPL from outdated PCs for BTE applications.

Gelatin has emerged as a biocompatible polymer with high printability in scaffold-based tissue engineering. The aim of the current study was to investigate the potential of genipin-crosslinked 3D printed gelatin scaffolds for temporomandibular joint (TMJ) cartilage regeneration. Crosslinking with genipin increased the stability and mechanical properties, without any cytotoxic effects. Chondrogenic differentiation of human bone marrow-derived mesenchymal stem cells (hBMSC) on the scaffolds were compared to cell pellets and spheres. Although hBMSC seeded scaffolds showed a lower expression of chondrogenesis-related genes compared to cell pellets and spheres, they demonstrated a significantly reduced expression of collagen (COL) 10, suggesting a decreased hypertrophic tendency. After 21 days, staining with Alcian blue and immunofluorescence for SOX9 and COL1 confirmed the chondrogenic differentiation of hBMSC on genipin-crosslinked gelatin scaffolds. In summary, 3D printed gelatin-genipin scaffolds supported the viability, attachment and chondrogenic differentiation of hBMSC, thus, demonstrating potential for TMJ cartilage regeneration applications.

Successful periodontal regeneration requires the hierarchical reorganization of multiple tissues including periodontal ligament, cementum, alveolar bone, and gingiva. The limitation of conventional regenerative therapies has been attracting research interest in tissue engineering-based periodontal therapies where progenitor cells, scaffolds, and bioactive molecules are delivered. Scaffolds offer not only structural support but also provide geometrical clue to guide cell fate. Additionally, functionalization improves bioactive properties to the scaffold. Various scaffold designs have been proposed for periodontal regeneration. These include the fabrication of biomimetic periodontal extracellular matrix, multiphasic scaffolds with tissue-specific layers, and personalized 3D printed scaffolds. This review summarizes the basic concept as well as the recent advancement of scaffold designing and fabrication for periodontal regeneration and provides an insight of future clinical translation.

Reconstruction of degenerated temporomandibular joint (TMJ) structures remains a clinical challenge. Tissue engineering (TE) is a promising alternative to current treatment options, where the TMJ is either left without functional components, or replaced with autogenous, allogeneic, or synthetic grafts. The objective of this systematic review was to answer the focused question: in experimental animal models, does the implantation of biomaterial scaffolds loaded with cells and/or growth factors (GFs) enhance regeneration of the discal or osteochondral TMJ tissues, compared with scaffolds alone, without cells, or GFs? Following PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analysis) guidelines, electronic databases were searched for relevant controlled preclinical in vivo studies. Thirty studies reporting TMJ TE strategies in both small (rodents, rabbits; n = 25) and large animals (dogs, sheep, goats; n = 5) reporting histological and/or radiographic outcomes were included. Twelve studies reported ectopic (subcutaneous) implantation models in rodents, whereas 18 studies reported orthotopic, surgically induced defect models in large animals. On average, studies presented with an unclear-to-high risk of bias. In most studies, mesenchymal stem cells or chondrocytes were used in combination with either natural or synthetic polymer scaffolds, aiming for either TMJ disc or condyle regeneration. In summary, the overall preclinical evidence (ectopic [n = 6] and orthotopic TMJ models [n = 6]) indicate that addition of chondrogenic and/or osteogenic cells to biomaterial scaffolds enhances the potential for TMJ tissue regeneration. Standardization of animal models and quantitative outcome evaluations (biomechanical, biochemical, histomorphometric, and radiographic) in future studies, would allow more reliable comparisons and increase the validity of the results.

Fetal bovine serum (FBS) is the most commonly used supplement for ex vivo expansion of human mesenchymal stem cells (hMSCs) for bone tissue engineering applications. However, from a clinical standpoint, it is important to substitute animal-derived products according to current good manufacturing practice (cGMP) guidelines. Humanized alternatives to FBS include three categories of products: human serum (HS), human platelet derivatives (HPDs)-including platelet lysate (PL) or platelet releasate (PR), produced by freeze/thawing or chemical activation of platelet concentrates, respectively, and chemically defined media (serum-free) (CDM). In this systematic literature review, the in vitro and in vivo osteogenic potential of hMSCs expanded in humanized (HS-, HPD-, or CDM-supplemented) media versus hMSCs expanded in FBS-supplemented media, was compared. In addition, PL and PR were compared in terms of their growth factor (GF)/cytokine-content and cell-culture efficacy. When using either 10-20% autologous or pooled HS, 3-10% pooled HPDs or CDM supplemented with GFs, in comparison with 10-20% FBS, a majority of studies reported similar or superior in vitro proliferation and osteogenic differentiation, and in vivo bone formation in ectopic or orthotopic rodent models. Moreover, a trend for higher GF content was observed in PL versus PR, although evidence for cell culture efficacy is limited. In summary, humanized supplements seem at least equally effective as FBS for hMSC expansion and osteogenic differentiation. Although pooled HPDs appear to be the most favorable supplement for large-scale hMSC expansion, further efforts are needed to standardize the preparation and composition of these products in compliance with cGMP standards.

The regenerative potential of tissue-engineered bone constructs may be enhanced by in vitro coculture and in vivo cotransplantation of vasculogenic and osteogenic (progenitor) cells. The objective of this study was to systematically review the literature to answer the focused question: In animal models, does cotransplantation of osteogenic and vasculogenic cells enhance bone regeneration in craniofacial defects, compared with solely osteogenic cell-seeded constructs? Following PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, electronic databases were searched for controlled animal studies reporting cotransplantation of endothelial cells (ECs) with mesenchymal stem cells (MSCs) or osteoblasts in craniofacial critical size defect (CSD) models. Twenty-two studies were included comparing outcomes of MSC/scaffold versus MSC+ EC/scaffold (co)transplantation in calvarial (n = 15) or alveolar (n = 7) CSDs of small (rodents, rabbits) and large animal (minipigs, dogs) models. On average, studies presented with an unclear to high risk of bias. MSCs were derived from autologous, allogeneic, xenogeneic, or human (bone marrow, adipose tissue, periosteum) sources; in six studies, ECs were derived from MSCs by endothelial differentiation. In most studies, MSCs and ECs were cocultured in vitro (2-17 days) before implantation. Coculture enhanced MSC osteogenic differentiation and an optimal MSC: EC seeding ratio of 1: 1 was identified. Alloplastic copolymer or composite scaffolds were most often used for in vivo implantation. Random effects meta-analyses were performed for histomorphometric and radiographic new bone formation (% NBF) and vessel formation in rodents' calvarial CSDs. A statistically significant benefit in favor of cotransplantation versus MSC-only transplantation for radiographic % NBF was observed in rat calvarial CSDs (weighted mean difference 7.80% [95% confidence interval: 1.39-14.21]); results for histomorphometric % NBF and vessel formation were inconclusive. Overall, heterogeneity in the meta-analyses was high (I-2 > 80%). In summary, craniofacial bone regeneration is enhanced by cotransplantation of vasculogenic and osteogenic cells. Although the direction of treatment outcome is in favor of cotransplantation strategies, the magnitude of treatment effect does not seem to be of relevance, unless proven otherwise in clinical studies.

Purpose: The objective of this study was to systematically review the available literature on three-dimensional time-dependent graft volume changes after sinus augmentation (SA) with different biomaterials in humans. Materials and Methods: MEDLINE, EMBASE, and CENTRAL were searched for related literature. Controlled and uncontrolled studies reporting volume changes of more than 10 SAs after at least 6 months, assessed by computed tomography (CT) or cone beam CT (CBCT), were eligible for inclusion. The primary outcome of interest was time-dependent percentage change in augmentation volume. Results: Seven controlled and five uncontrolled studies (n = 234 SAs) with a high risk of bias were included and reported on a range of graft materials. Autogenous bone (AB) was used in the particulate or block form. Bone substitutes (BS) were used either alone or in combination with other materials as composite grafts (CG). All studies reported reductions in augmentation volumes over time (AVR), generally after short observation periods (range, 6 months to 6 years). Substantial AVRs (approximately 45% in 77 SAs) were reported for AB after 6 months and up to 2 years. AVRs for solely BS or CG were relatively lower (approximately 18% to 22% in 142 SAs) after a similar time period. All studies reported a wide range of volume reductions. No significant differences in AVR were observed between different graft materials. Because of insufficient long-term data, a reliable association between volume reduction and time could not be established. Conclusion: Some loss of augmentation volume always occurs after SA during early healing times. In general, less AVR may be expected after SA with BS or CG compared to SA with AB. Augmentation volume loss does not seem to compromise implant placement or survival.

Introduction Odontogenic infections are a common cause of maxillary sinusitis. This study aimed to evaluate the relationship between teeth with periapical lesions or periodontal disease and sinus mucosal thickening using cone-beam computed tomography (CBCT) imaging. Methods CBCT scans of 243 patients (485 sinuses) were evaluated retrospectively for the presence of periapical lesions and/or periodontal disease in posterior maxillary teeth and associated sinus mucosal thickening. Thickening >2 mm was considered pathological and was categorized by degree (2–5 mm, 5–10 mm, and >10 mm) and type (flat or polypoid). Descriptive, bivariate, and multivariate statistical analyses were performed. Results Mucosal thickening >2 mm was observed in 147 (60.5%) patients and 211 (44.6%) sinuses and was mostly of a "flat" type. Bivariate analysis revealed significant associations between mucosal thickening >2 mm and sex (males), age (>60 years), and teeth with periapical lesions and periodontal disease ( P ≤ .027). Multivariate regression analysis identified only sex (males, odds ratio=1.98, P = .004) and teeth with periapical lesions (odds ratio=9.75, P 2 mm. Conclusions Sinus mucosal thickening is a common radiographic finding, which is more likely to be observed in males (2×) and in relation to teeth with periapical lesions (9.75×).

Background Periodontal disease negatively affects oral health-related quality of life (OHRQoL). While there is sufficient evidence for the clinical efficacy of periodontal therapy, data on patient-based outcomes are limited. Objectives To systematically review the available evidence on the impact of periodontal therapy on OHRQoL in adults. Material & Methods MEDLINE, EMBASE, CENTRAL and LILACS were searched without language restrictions. Longitudinal observational and intervention studies assessing changes in OHRQoL using validated measures, in adults with periodontal disease undergoing non-surgical (NST) or surgical therapy (ST), were eligible for inclusion. Study quality was assessed using the Newcastle-Ottawa scale and CONSORT-checklist. No meta-analysis was performed. Results Eleven studies (seven prospective case-series', one controlled before-after study and three randomized controlled trials) of “medium” methodological quality were included in the review. All studies reported impaired OHRQoL before therapy. Nine studies reported a statistically significant improvement in OHRQoL after NST (follow-up = 1 week to 12 months, p

Objective To determine, using cone-beam computed tomography (CBCT), the residual ridge height (RRH), sinus floor membrane thickness (MT), and ostium patency (OP) in patients being evaluated for implant placement in the posterior maxilla. Materials and methods CBCT scans of 128 patients (199 sinuses) with ≥1 missing teeth in the posterior maxilla were examined. RRH and MT corresponding to each edentulous site were measured. MT >2 mm was considered pathological and categorized by degree of thickening (2–5, 5–10 mm, and >10 mm). Mucosal appearance was classified as “normal”, “flat thickening”, or “polypoid thickening”, and OP was classified as “patent” or “obstructed”. Descriptive and bivariate statistical analyses were performed. Results MT >2 mm was observed in 60.6% patients and 53.6% sinuses. Flat and polypoid mucosal thickening had a prevalence of 38.1% and 15.5%, respectively. RRH ≤4 mm was observed in 46.9% and 48.9% of edentulous first and second molar sites, respectively. Ostium obstruction was observed in 13.1% sinuses and was associated with MT of 2–5 mm (6.7%), 5–10 mm (24%), and >10 mm (35.3%, P 2 mm) and reduced residual ridge heights (≤4 mm) were highly prevalent in this sample of patients with missing posterior maxillary teeth. Membrane thickening >5 mm, especially of a polypoid type, is associated with an increased risk for ostium obstruction. In the presence of these findings, an ENT referral may be beneficial prior to implant-related sinus floor elevation.

To evaluate smokeless tobacco cessation in communities of South Asian origin.Multi-centre prospective cohort study.Three tobacco cessation services offering specialist smokeless tobacco cessation outreach clinic support to South Asians (Bangladeshi, Indian and Pakistani) resident in England.A total of 239 South Asian participants seeking to stop smokeless tobacco use between November 2010 and December 2011.Socio-demographics, tobacco use and dependence, self-reported abstinence at 4 weeks and satisfaction measures.Participants' mean age was 45 [standard deviation (SD) = 13] years, were predominantly female (76%), of Bangladeshi origin (74%), either home carers (53%) or not working (29%). Sixty-three per cent were recruited from community locations, 21% through a clinical contact and 16% through friends and family. Mean daily number of smokeless tobacco intakes was 10 (SD = 7) and the mean dependence score was 4.5 (SD = 1.9). Sixty-three per cent of participants achieved continuous abstinence 4 weeks after quitting. Using nicotine replacement therapy (NRT) versus not using it [OR = 3.47, 95% confidence interval (CI): 1.25, 9.62] and below median (≤ 8) daily smokeless tobacco intakes (OR = 1.91, 95% CI: 1.07, 3.40) predicted successful abstinence.South Asian smokeless tobacco users resident in England accessing services to help them stop appear to have short-term success rates comparable with smokers attending stop-smoking services, with higher success rates being reported by those using nicotine replacement therapy.

To identify predictors of short-term smokeless tobacco cessation in Bangladeshi women resident in the United Kingdom. Prospective cohort study. A tobacco cessation service offering culturally tailored smokeless tobacco cessation support. A total of 419 Bangladeshi women chewing paan with tobacco. Demographics, tobacco use and dependence and cessation attempt process and outcomes. Client mean age was 48.92 [95% confidence interval (CI) 47.5, 50.34] years and the mean area social deprivation score was 3.65 (95% CI 3.33, 3.97). Mean daily smokeless tobacco intakes, as paan, was 9.96 (95% CI 9.22, 10.7); 69.8% were recruited from primary care, 78.8% received behavioural support and nicotine replacement therapy (NRT) and the remainder behavioural support alone. Self-reported 4-week continuous abstinence was 58.3%, predicted by NRT use [odds ratio (OR) = 4.93, 95% CI 2.02, 12.00], community recruitment (OR = 1.84, 95% CI 1.01, 3.35) and relatively lower social deprivation (IMD) score (OR = 1.98, 95% CI 1.18, 3.33). Bangladeshi women in the UK attending clinics to help cessation of paan with tobacco appear to be more likely to be successful in the short term if they use nicotine replacement therapy, are recruited via the community and have relatively lower levels of social deprivation.