Extracellular Vesicles of GMSCs Alleviate Aging-Related Cell Senescence.

Healthy aging is a complex biological process with progressive accumulation of senescent cells characterized by stable cell cycle arrest, resulting in impaired homeostasis, regenerative potential, and gradual functional decline in multiple tissues and organs, whereby the aberrant activation of mammalian target of rapamycin (mTOR) signaling networks plays a central role. Herein, we explored the effects of extracellular vesicles (EVs) released by gingiva-derived mesenchymal stem cells (GMSC-EVs) on oxidative stress-induced cellular senescence in human endothelial cells and skin fibroblasts and their antiaging potentials. Our results showed that GMSC-EVs robustly abrogated oxidative stress-induced upregulation in the expression of cellular senescence-related genes, such as ß-galactosidase, p21, p53, and γH2AX, and mTOR/pS6 signaling pathway, in human umbilical vein endothelial cells (HUVECs) and skin fibroblasts. Meanwhile, GMSC-EVs restored oxidative stress-induced impairment in proliferation and tube formation by HUVECs. Systemic administration of GMSC-EVs attenuated aging-associated elevation in the expression levels of p21, mTOR/pS6, interleukin 6, and tumor necrosis factor α in skin and heart tissues of aged mice. These findings suggest that GMSC-EVs could be a potential alternative source of cell-free product for attenuation of aging-related skin and vascular dysfunctions due to their potent inhibitory effects on oxidative stress-induced cellular senescence in endothelial cells and skin fibroblasts.

Analysis of mandibular motion following unilateral and bilateral alloplastic TMJ reconstruction.

The purpose of this study was to analyse the masticatory patterns and range of motion (maximal incisal opening (MIO), protrusion and lateral excursion) in patients who have had unilateral and bilateral temporomandibular joint (TMJ) replacement with an alloplastic prosthesis, and compare them to each other and to normal controls. Mandibular motion was examined in 18 patients, who had undergone alloplastic TMJ reconstruction, 13 with a bilateral prosthesis and 5 with a unilateral prosthesis, and in 13 normal controls. A statistically significant difference (P<0.01) for MIO and maximum lateral excursion was observed between the bilateral group and the control group. Maximum protrusion was only statistically significantly different (P<0.05) between the bilateral group and the control group. For the unilateral group, a statistically significant difference (P<0.01) was seen only with maximum contralateral excursion when compared with controls. No statistically significant difference existed in MIO and protrusion between the unilateral and bilateral groups. Even though maximum ipsilateral lateral excursion was greater for the unilateral group than either left or right maximum lateral excursion by the bilateral group, this difference was not statistically significant. This study provided an in vivo analysis of mandibular motion following alloplastic TMJ reconstruction.

Descending necrotizing mediastinitis as a complication of odontogenic infection.

Descending necrotizing mediastinitis (DNM) is a serious, life threatening complication that can occur from a common odontogenic infection. Even with advancements in antibiotics, diagnostic imaging, and surgical management, the mortality rate remains between 20 and 40%. It is imperative that the practitioner taking care of patients with odontogenic infections be sensitized to this potentially fatal complication. We report the successful management of a case of mediastinitis complicating an odontogenic infection in a 39-year-old male.

Post-surgical neuromas in patients with total alloplastic temporomandibular joint reconstruction: a retrospective case series.

This study evaluated pain scores and maximal incisal opening (MIO) in patients with total alloplastic temporomandibular joints found to have post-surgical neuromas following revision arthroplasty, compared with patients who underwent revision arthroplasty without neuromas. 19 cases were reviewed of which 11 had neuromas excised. Data were available for 8 cases in the immediate postoperative period and 7 cases had follow-up data. 8 patients had revision arthroplasty with excision of scar tissue (7 with postoperative, 4 with long-term data). Follow-up ranged from 2 months to 5.9 years (mean 1.2 years). 6 of 8 patients obtained clinically significant pain reduction in the immediate postoperative period when their neuromas were excised, compared with 3 of 7 patients without neuromas. On long-term follow-up, 3 of 7 patients in the neuroma group had clinically significant pain reduction, 3 reported lower pain scores, 1 had no pain change. No patients had increased pain. 1 of 4 patients in the scar revision group had clinically significant pain reduction, 2 had no change, 1 reported increased pain. Mean MIO was 23 mm preoperative and 28 mm postoperative in patients with neuromas, compared with 27.75 mm and 31.25 mm, respectively, in patients without neuromas.