In Vitro Evaluation of Proliferation and Migration Behaviour of Human Bone Marrow-Derived Mesenchymal Stem Cells in Presence of Platelet-Rich Plasma.

OBJECTIVE: To access the effects of platelet-rich plasma (PRP) on the behaviour of human bone marrow-derived mesenchymal stem cells (hBMSCs), including proliferation and migration. METHODS: PRP was diluted with DMEM/F12, resulting in concentrations of 1%, 2%, and 5%. The proliferation of hBMSCs was examined by 2 methods: cell-number counting with the haemocytometer method and the colony-forming unit-fibroblast (CFU-F) assay. Cell migration was evaluated using the scratch wound healing (SWH) assay; after that, the recorded digital images were analysed by the Image-Analysis J 1.51j8 software to compare the cell-free areas between groups after 0, 24, and 48 hours. RESULTS: hBMSCs cultured in DMEM/F12 at PRP concentrations of 1%, 2%, and 5% were all able to proliferate and migrate. In the 5% PRP group, hBMSCs proliferated greatly with a significantly higher cell number than reported for all other groups on days 5, 7, and 9. CFU-Fs were observed in all groups, except for the negative control group. The SWH assay demonstrated that hBMSCs cultured in 2% and 5% PRP almost filled the artificial wound scratch and significantly migrated more than those of all other groups at both 24 h and 48 h. CONCLUSION: This study indicated that, due to the significant enhancement of cell proliferation and migration, 5% PRP might be the optimal concentration that should be used to promote the potential of hBMSCs in wound healing.

An Update on Anti-CD137 Antibodies in Immunotherapies for Cancer.

The selective expression of CD137 on cells of the immune system (e.g., T and DC cells) and oncogenic cells in several types of cancer leads this molecule to be an attractive target to discover cancer immunotherapy. Therefore, specific antibodies against CD137 are being studied and developed aiming to activate and enhance anti-cancer immune responses as well as suppress oncogenic cells. Accumulating evidence suggests that anti-CD137 antibodies can be used separately to prevent tumor in some cases, while in other cases, these antibodies need to be co-administered with other antibodies or drugs/vaccines/regents for a better performance. Thus, in this work, we aim to update and discuss current knowledge about anti-cancer effects of anti-CD137 antibodies as mono- and combined-immunotherapies.

Periodontal Status of the Adjacent Second Molar after Impacted Mandibular Third Molar Surgical Extraction.

OBJECTIVE: The purpose of this study was to evaluate the change in periodontal status of the adjacent second molar of the impacted mandibular third molar after surgical extraction and its association with the third molar condition in the presurgical stages, including position, eruption level, and local complications. MATERIALS AND METHODS: The study was based on a 6-month follow-up of 38 patients (19 males and 19 females; Mean age: 21.89 ± 2.74) recruited consecutively after surgical extraction of an impacted lower third molar. The third molar's presurgical position, eruption level, and local complications were examined. Periodontal status, including Plaque Index (PI), Gingival Index (GI), and gingival bleeding on probing (BOP), of the teeth in the adjacent sextant was clinically evaluated. The pocket depth (PD) and the distance between the epithelial attachment and the adjacent second molar's occlusal surface were clinically measured; and the distance between the alveolar bone crest and cementoenamel junction (AC-CEJ) of the adjacent second molar was evaluated by the periapical film. All measures were recorded at the time of surgery and 1, 3, and 6 months after surgery. RESULTS: The values of PI, GI, BOP, PD, and EA-OS were significantly reduced after 1, 3, and 6 months compared to baseline data. The AC-CEJ was decreased after 1 month but significantly increased after 3 and 6 months. Presurgical local complications of the impacted third molar mostly were significantly associated with the periodontal status of the adjacent sextant. CONCLUSION: There was a significant improvement of periodontal conditions of the second molar and adjacent sextant after impacted third molar surgery.

Periodontal status of anterior teeth following clinical crown lengthening by minimally traumatic controlled surgical extrusion.

BACKGROUND/AIMS: The number of fractured anterior teeth following trauma has been increasing while not every patient is able to afford a dental implant instead of maintaining the injured tooth. Thus, a tooth conservation solution is required to place an aesthetic and functional restoration without biologic width violation. The aim of this study was to evaluate the effectiveness of minimally traumatic controlled surgical extrusion in fractured anterior teeth crown lengthening by assessing the periodontal status through clinical examination and radiographs. METHODS: This longitudinal observational study investigated a group of 18 patients (six males and 12 females) at the Department of Periodontology, National Hospital of Odonto-stomatology, Ho Chi Minh City, Vietnam. Following pre-surgery procedures and examination, minimally traumatic controlled surgical extrusion was carried out using a periotome. Patients were examined at four follow-up appointments after 1 week, 1, 3 and 6 months to record the following experimental variables: periodontal parameters including the gingival index (GI), pocket depth (PD), bleeding on probing (BOP), mobility, marginal gingiva position, alveolar ridge resorption, periapical osteogenesis, tooth resorption and ankylosis. RESULTS: All periodontal parameters were significantly decreased at 3 and 6 months post-procedure (P < 0.001). Tooth mobility decreased gradually following surgery, and at 6 months, all teeth became normal at level 0. Periapical osteogenesis changes were significantly increased at 1, 3 and 6 months in comparison with pre-surgery (P < 0.001). Marginal gingiva position and alveolar ridge resorption were not significantly different between pre-surgery and 1, 3 and 6 months post-surgery. No cases of root resorption or ankylosis were observed at 6 months post-surgery. CONCLUSION: A minimally traumatic controlled surgical extrusion technique for clinical crown lengthening yielded highly successful results in both aesthetic and functional aspects, and no cases had unfavourable outcomes during the 6-month follow-up period.

Dental and periodontal problems of elderly people in Vietnamese nursing homes.

OBJECTIVE: To determine the oral health status and treatment needs of elderly residents in Vietnamese nursing homes. METHODS: This study was conducted among 360 men and 431 women with a mean age of 72.9 ± 9.1 years in three nursing homes in Ho Chi Minh City. Demographic information on education, duration of stay, chronic diseases, tooth brushing and tobacco use were obtained from medical records and a questionnaire. The oral health of participants was clinically assessed by a dental examiner using WHO criteria. Oral health status included estimates of coronal and root caries, periodontal disease, denture status and dental treatment needs. RESULTS: Nearly all (90.1%) of the participants had natural teeth. The mean numbers of teeth with coronal or root decay were 5.8 ± 4.0 and 6.0 ± 4.2, respectively, and almost everyone required at least one restoration for coronal or root caries. Most of the participants with natural teeth had bleeding gingiva on probing, 26.2% had deep periodontal pockets, 96.5% needed oral hygiene improvement plus scaling and 20.3% required complex periodontal treatment. None of the edentulous participants had dentures, and 86.6% required new or repaired dentures. CONCLUSION: The prevalence of untreated oral diseases is very high and the need for dental care extensive among the residents of government-administered long-term care facilities in Ho Chi Minh City.

Effects of platelet-rich plasma on human gingival fibroblast proliferation and migration in vitro

Abstract Objective This study evaluated the influence of platelet-rich plasma (PRP) on the behaviour of human gingival fibroblasts (hGFs), including fibroblast proliferation, migration and colony formation. Methods PRP was obtained from the human peripheral blood of a healthy volunteer and then was diluted into platelet concentrations of 1%, 2% and 5%. The proliferation of hGFs was determined by two methods: (1) Cell-number counting with a haemocytometer method at days 1, 3, 5 and 7; (2) Colony-forming unit-fibroblast (CFU-F) assay at 2 weeks. The migration of hGFs was evaluated with scratch assay, then recorded digital images were analysed by Image-Analysis J 1.51j8 software to compare the remaining artificial wound areas between PRP groups at 0, 24 and 48 hours. Results All hGFs that were cultivated in media with 1%, 2% and 5% PRP showed their ability to proliferate and migrate. Cell numbers incubated with 1% PRP increased significantly during the first three days and peaked at day 5, tending to be similar to their proliferation in complete medium. With concentrations of 2% and 5% PRP, hGFs outgrew and peaked at day 3, which was faster than with those in medium with 1% PRP. Especially, hGFs in the group 5% PRP proliferated with higher cell numbers than those in the other remaining groups at day 3. The hGF colony number that was formed in the group 5% PRP was significantly higher than those in the groups 1% and 2% PRP. Scratch assay showed hGFs in the groups 2% and 5% PRP almost filled the artificial wound and migrated more effectively than in the group 1% PRP at 24 hours, which was significant. Conclusion In this study, perhaps the medium with 5% PRP is the dominant option, promoting the abilities of hGFs to heal wounds, because of its fast and effective impact on cell proliferation, colony formation and migration.