Clinical follow-up observation of 84 cases of implant-retained/supported prostheses in edentulous patients / 中华口腔医学杂志

Objectives@#To evaluate the long-term clinical results and patient satisfaction of implant-retained/supported prostheses in edentulous patient based on retrospectively summary of the clinical data of implant-retained/supported prostheses patients.@*Methods@#Edentulous patients who received implant denture treatment between 01/2005 and 12/2016 was included in this study. Soft tissue health, clinical examination, X-ray observation, patient satisfaction with implant-retained/supported prostheses were evaluated.@*Results@#A total of 400 implants in 84 cases (96 jaws), 35 fixed bridges and 61 overdentures. The follow-up time was (34.3±25.5) months. The 3- and 5-year implant cumulative survival rate of implant-supported overdenture was 95.0% and 92.1%, and the 3- and 5- year survival rate of implant-supported fixed denture was both 99.9%. The prevalence of peri-implantitis was 2.8% (11/400). A total of 44% (27/61) of the overdenture and 23%(8/35) of the fixed denture were repaired due to the complications of prosthesis. The mean repair frequency was (1.4±1.2) in overdenture and (1.3±0.9) in fixed denture (t=0.490, P=0.600). The average probing depth around implant recorded in the overdenture group [(2.2±1.1) mm] was significantly greater than that in the fixed denture group [(1.4±1.2) mm] (t=3.300, P=0.002). Patient satisfaction with an average of (6.5±4.9) in implant-support overdenture group was significantly higher than that in implant-support fixed denture group (3.2±2.8) (t=3.218, P=0.006).@*Conclusions@#The complication rate of the prosthesis was high in edentulous patients with implant-retained/supported prostheses. Besides, the patients with implant supported denture expressed more satisfaction with their prostheses. And there was a relatively high implant cumulative survival rate of implant-retained/supported prostheses in edentulous patient.

Effects of 50 Hz sinusoidal electromagnetic field with different intensities on rat peak bone mass / 生物医学工程学杂志

Studying effects of 50 Hz sinusoidal electromagnetic fields (SEMFs) with different intensities on peak bone mass (PBM) of rats may provide a theoretical basis for application of electromagnetic clinical field. 30 female SD rats, 6 weeks of age, were randomly divided into three groups: the control group, 0.1 mT electromagnetic field group (EMFs) and 0.6 mT EMFs. The EMFs groups were treated for 3 h/day. After 8 weeks, we examined their bone mineral densities (BMD) , measured their bone biomechanical properties, and made serum levels of osteocalcin (OC), tartrate-resistant acid phosphatase 5b (TRACP 5b), and histomorphometry. It was found that the BMD (P < 0.01), maximum mechanical load (P < 0.01) in the 0.1 mT group were significantly higher than those in the control group, and Yield strength (P < 0.05), the analyses of serum bone turnover markers and histomorphometric parameters were better than those in the control group (P < 0.05). However, the 0.6 mT group did not have significantly difference comparing with that in the control group. This study proved that 50 Hz 0.1 mT SEMFs can increased BMD, bone strength, and bone tissue microstructure. Therefore, 50 Hz 0.1 mT SEMFs can improve peak bone mass of rats.

Short-term evaluation of clinical effect of bone ring grafting and immediate insertion / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To observe the short-term clinical effectiveness of bone ring graft technique and to summarize the key points of related surgical operation to provide comprehensive clinical guidelines.</p><p><b>METHODS</b>Fifteen patients with severe alveolar bone absorption were selected to receive bone ring grafting and immediate dental implant. Final fixed prostheses were cemented five months after initial implantation. Cone beam CT scans were conducted on all subjects before the procedure, as well as four months post-operation to evaluate alveolar bone height and level of bone height and absorption around the implants. Four to six months after prosthesis installation, each implant's Jemt classification, gingiva attachment, and probing depth (PD) were analyzed. The difference of PD between implants and adjacent teeth, as well as the difference of the bone absorption between labial and lingual sides, was compared. The survival rate of the bone ring and the retention rate of implants were calculated. Complications and patient satisfaction were also investigated.</p><p><b>RESULTS</b>Bone graft survival rate was 94.4% and dental implantation retention rate was 100% four months post-operation. Average bone level increase was (6.06 +/- 1.06) mm, average bone absorption was (1.33 +/- 0.84) mm, and average bone thickness at the neck of the dental implant body was (6.94 +/- 0.73) mm. Approximately 4 to 6 months after crown restoration, average bone level increase was (5.62 +/- 1.03) mm, average bone absorption was (1.51 +/- 1.02) mm, and average bone thickness at the neck of the dental implant body was (6.77 +/- 0.72) mm. The PD around the implant body and the adjacent teeth was statistically insignificant. No major post-operative complication was observed, restorations were successful, and patient satisfaction level was high.</p><p><b>CONCLUSION</b>Bone ring graft technique and immediate dental implantation are relatively simple to perform, and these techniques facilitate reduction in required treatment time. Short-term effect is reliable and satisfactory, whereas long-term outcomes require further follow up and study.</p>

Effect of genistein on rat femoral bone metabolic activity in vitro / 药学学报

This study is to investigate effects of genistein on rat femoral bone metabolic in vitro. Rat femoral tissues was isolated and randomly divided into two groups including control group and genistein (1 x 10(-5) mol x(-1)) group. Determinations of alkaline phosphatase (ALP) activity, calcium content and osteoprotegerin (OPG), type I-collagen (Collagen-I), RANKL, Runx-2 and bone morphogenetic protein (BMP-2) mRNA expression were done by real-time PCR. The results showed that 1 x 10(-5) mol x L(-1) genistein could increase the activity of ALP and contents of Ca, regulate bone metabolism activity of OPG, RANKL, BMP-2, Collagen-I and Runx-2 mRNA expression level. Genistein can significantly modulate bone metabolism related gene expression level of rat femoral tissue in vitro, and can increase calcium content and the activity of ALP.

Inhibitory effect of 8-prenylnaringenin on osteoclastogensis of bone marrow cells and bone resorption activity / 药学学报

This study is to investigate the effect of 8-prenylnaringenin (8-PNG) on osteoclastogensis of bone marrow cells and bone resorption activity of osteoclasts. Osteoclasts were separated from long bone marrow of newborn rabbits and cultured in alpha-MEM containing 10% FBS. 8-PNG was added into culture media at 1 x 10(-7), 1 x 10(-6), 1 x 10(-5) mol xL(-1), separately. 17beta-Estradiol (E2, 1 x 10(-7) mol x L(-7)) was used as positive control. T RAP staining and TRAP activity measurement were performed after 5 days, and the bone resorption pits were analyzed after 7 days. Annexin V staining for the detection of apoptotic osteoclasts was performed after 2, 4, 8, 12, 24, 36 and 48 h separately. The mRNA expression level of TRAP and cathepsin K (CTSK) was measured by real-time RT-PCR. 8-PNG significantly reduced the number of osteoclasts which was TRAP staining positive and with more than three nucleus, the area and number of bone resorption pits decreased obviously in 8-PNG-supplemented groups. The apoptosis rate peaked earlier in the 8-PNG-supplemented groups and the mRNA expression level of TRAP and CTSK decreased significantly. All these inhibitory effects were in a dose dependent manner, the highest effect was obtained by 1 x 10(-5) mol x L(-1) 8-PNG. 8-PNG inhibits bone resorption activity of osteoclasts by inducing osteoclast apoptosis and inhibiting the gene expression and enzyme activity including TRAP and CTSK, and restrains bone marrow cells to osteoclast differentiation.

Effect of sinusoidal electromagnetic fields on rats femur tissue cultivation in vitro / 生物医学工程学杂志

The present research was aimed to investigate the effect of 50Hz, 1. 8mT of sinusoidal electromagnetic fields(SEMFs)on femur tissue cultivation in vitro. The rat femur tissue was isolated from SD rats by method of enzyme digestion, and randomly divided into two groups: SEMFs group and control. The femur tissue of SEMFs groups were exposured under 50Hz 1. 8mT of SEMFs for 1. 5h/time/d, but those in the control groups were without SEMFs treatment. The correlative gene was detected by the Real-time RT-PCR that after SEMFs treatment for 0 (first times treatments is 0 days), 1, 2, 3, 4 and 5d. The alkaline phosphatase (ALP) activity was measured after SEMFs treatment for 3, 6, 9 and 12d respectively. The calcium content was detected after SEMFs treatment for 3, 6, 9 and 12d. The results showed that the OPG and Collagen-1 mRNA expression level was kept at a relatively stable level by SEMFs in the SEMFs group significantly. The Runx-2 mRNA expression level was significantly increased after the SEMFs treatment for 1d and 5d. The ALP activity of femur tissue was significantly increased alter SEMFs treatment for 3d and 9d. The calcium content was higher than untreated groups after SEMFs treatment for 6, 9 and 12d. The SEMFs promoted OPG, Collagen-1, Runx-2 mRNA expression level, ALP activity and calcium content. The result indicated that SEMFs increased the metabolism activity of femur tissues.

Study of labeling human periodontal ligament stem cells with enhanced green fluorescent protein by lentivirus vector infection / 华西口腔医学杂志

<p><b>OBJECTIVE</b>The aim of this study is to optimize conditions for labeling human periodontal ligament stem cells (PDLSCs) using enhanced green fluorescent protein (eGFP) infected by lentivirus vector and to obtain PDLSCs with high stable expressed eGFP.</p><p><b>METHODS</b>PDLSCs were transfected with eGFP by lentivirus vector for 48 h via different multiplicity of infection (MOI) (25, 50, 100, 200 and 400) and the infection efficiency were analyzed by both fluorescent microscope and flow cytometry. The proliferation rate of infected PDLSCs was evaluated by MTT. The infected PDLSCs were further for detection of pluripotent, differentiation ability and alkaline phosphatase (ALP) expression ability.</p><p><b>RESULTS</b>The infection efficiency for each group were 44.7%, 60.9%, 71.7%, 85.8% and 86.9% respectively. Proliferation of PDLSCs was not affected when MOI was below 200; however, at MOI 400, the proliferation ability was affected compared with control group. The pluripotent and ALP abilities of PDLSCs were not changed by the infection.</p><p><b>CONCLUSION</b>Infection for 48 h at MOI 200 is optimal for labeling PDLSCs with eGFP using lentivirus vector, and the proliferation and differentiation abilities of PDLSCs are not affected obviously.</p>

Three-dimension finite element analyses of interior stress of two kinds of Replace implant / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To establish three-dimension finite element model of mandible with two kinds of Replace implant, and to study stress of implant and abutment.</p><p><b>METHODS</b>The data of components of the dental implant was measured, cross section of the mandible was scanned by spiral CT and image reconstruction technique was conducted. Three-dimension finite element analysis software UG and MSC. Marc/Mentat were used to built the conjunction model and bone model of two implant systems. Axial loading (200N) and 30 degrees oblique loading (100N) were applied on the models respectively, the stress distribution patterns of the implant and abutment of two implant systems were analyzed.</p><p><b>RESULTS</b>The peak stress district was concentrated on the structure of the implant cervix, which was more obviously displayed on the Replace Select implant. The peak stress of oblique loading was higher than that of axial loading. The peak stress on the implant cervix of Replace Select implant was higher than that of Replace External Hex implant in all loadings.</p><p><b>CONCLUSION</b>To Replace Select especially, oblique force should be avoided on clinical practice in case of the implant fracture.</p>