Analysis of causes for dental implant failure / 口腔医学

@#The implant-supported prosthesis has gradually become the preferred treatment for patients with partial edentulous or complete edentulous. Causes for the implant failure have been discussed in the majority of studies conducted in recent years, while their risk factors are still controversial. Patient factors (gender, age, smoking, osteoporosis, diabetes, medication, periodontitis and bruxism), clinical parameters (implant area, bone quality, implant size) and doctor factors (surgical-related factors, prosthesis-related factors) will all affect implant failure. This article presents typical clinical cases and reviews the potential risk factors for dental implant failure, in order to provide guidance for clinical practice.

Research progress in maxillary sinus mucosal disease associated with maxillary sinus floor lifting / 中华口腔医学杂志

Maxillary sinus augmentation is an effective procedure to gain bone height for implant placement in an atrophic posterior maxilla. But maxillary sinus diseases are prevalent in patients scheduled for sinus lift procedures. The presence of these diseases may increase the difficulties in performing the surgery and the risk of developing postoperative complications. This paper summarizes and introduces the common maxillary sinus mucosa diseases related to maxillary sinus augmentation.

The use of antibiotics in dental implantology / 中华口腔医学杂志

The use of antibiotics in dental implantology is very common and the abuse of antibiotics is increasingly obvious. The rational use of antibiotics in the process of oral implantology needs the support of evidence based medicine. The prophylactic use of antibiotics in dental implantology is reviewed in this article, including the summary of different infection risks, such as peri-implantitis and maxillary sinusitis after maxillary sinus floor lifting.

Application of modified lateral window for maxillary sinus floor augmentation / 浙江大学学报·医学版

Objective: To evaluate the clinical efficacy of modified lateral window for maxillary sinus floor augmentation (MSFA). Methods: Fifty-five patients who visited the Stomatology Hospital Affiliated to Zhejiang University School of Medicine between June 2012 and October 2014 were enrolled in the study. Patients underwent MSFA with Bio-Oss grafts based on modified access window. During the operation the vertical height of the bony window was reduced from 6-8 mm of conventional oval window to 4-5 mm of slot-shaped window. The sinus membrane was detached completely via the lateral access and large particle Bio-Oss graft was placed in the sub-mucosal space. The implant survival, graft height, graft volume and resorption rates were measured. Intra-op and post-op complications were recorded. Results: There were 86 implants inserted. The 2-4 year cumulative survival rates were 97.67% by implant-based analysis and 96.36% by patient-based analysis. The residual bone height was (4.7±2.6) mm and bone width was (8.4±2.7) mm. The bone height of implantation site immediately after operation was (16.1±2.5) mm and it was (16.2±2.2) mm at restoration. The bone heights at 1 and 2 years after operation were (14.9±2.5) mm and (13.6±2.6) mm, respectively. The graft height was (10.6±2.8) mm and the graft volume was (1569±745) mm3 immediately after operation. The resorption rate of graft height 6 months after operation was 3.79% and that of graft volume was 7.87%. The 1-year accumulative resorption rate of graft height was 6.63% and that of graft volume was 10.89%. The 2-year accumulative resorption rate of graft height was 7.58% and that of graft volume was 15.26%. Small membrane perforation during MSFA was observed in 5 cases and all were successfully repaired by a collagen Bio-Gide membrane. Conclusion: The modified lateral technique obtains high implant survival rate, excellent graft stability and low complication rate at 2-4 year clinical follow-up, indicating that it is a safe, predictable and minimally invasive surgical method for severe atrophic maxillary posterior dentition.

Design and in vitro evaluation of simvastatin-hydroxyapatite coatings by an electrochemical process on titanium surfaces.

The aim of this study was to deposit simvastatin-hydroxyapatite (sim-HA) coatings on titanium surfaces by an electrochemical process and evaluate osteoprogenitor cell responses to sim-HA-coated surfaces. Simvastatin was prepared onto titanium surfaces with varying concentration (10(-7), 10(-6), 10(-5) and 10(-4) mol/L). Surface characteristics were performed by FSEM, XRD and FTIR. LC-MS/MS method was used for simvastatin quantification in Sim-HA-coated surfaces. Murine calvaria-derived pre-osteoblastic cell (MC3T3-E1) proliferation, alkaline phosphatase activity (ALP) and osteocalcin release were used to measure osteoblastic activities. FSEM observation showed rod-like HA crystals covered on all surfaces. As drug concentration increased, the crystal diameter decreased. XRD and FTIR observations showed all coatings consisted of HA. LC-MS/MS test showed the simvastatin concentration in 10(-6) mol/L group was 2.77 x 10(-7) mol/L/cm2, while in 10(-7) mol/L group was 1.89 x 10(-7) mol/L/cm2. MC3T3-E1 cells grown on 10(-7) mol/L and 10(-6) mol/L Sim-HA surfaces showed increased ALP activity as compared to HA-coated surfaces on day 7 (P < 0.05) while at 10 day, all Sim-HA groups were significantly increased than HA group (P < 0.05). Two Sim-HA groups showed significant increases in osteocalcin production on 7 10 and 14 day (P < 0.05). It showed that incubation with 10(-7) mol/L simvastatin enhanced the cell proliferation to a statistically significant extent (P < 0.05) compared with the HA group at day 7. It was concluded that simvastatin was successfully deposited into HA coatings using the electrochemical process and the sim-HA coatings enhanced differentiation of osteoprogenitor cells.

Current status and influencing factors of oral health behavior among the elderly living in Gongshu District of Hangzhou City / 中华健康管理学杂志

Objective To explore the current status and influencing factors of oral health knowledge and behavior among the elderly living in Gongshu District of Hangzhou City.Methods A total of 600 elderly individuals were selected by multi-stage stratified cluster random sampling and interviewed with a self-designed questionnaire which included demographic characteristics and oral health knowledge and behavior.The status and influencing factors of oral health behavior were analyzed by single and multiplefactor analysis methods.Results A questionnaire survey was conducted among 600 elderly residents,with a response rate of 99.3％ (596/600) and an effective response rate of 94.1％ (561/600).The rate of good oral hygiene was 50.4％.Those elderly with different age,education level,medical insurance and oral hygiene showed significant difference in qualified rate of oral health behavior (x2 values were 10.79,21.32,5.72 and 16.33,respectively; all P＜0.05).In Logistic regression model,education level was positively correlated with oral health behavior among the elderly,and the qualified rate of oral health behavior of the elderly with education level of junior school or above was 2.69 times higher than that of illiterate elderly (x2=10.53,P=0.001).Conclusion The awareness rate of oral health knowledge among the elderly living in Gongshu District of Hangzhou City is at a relatively higher level,though oral health behavior is moderate.Age,education level,medical insurance and oral hygiene could be impacting factors of oral health behavior.

Fast formation of biomimetic apatite coatings on pure porous titanium implant's surface / 生物医学工程学杂志

The aim of this study was to elaborate a dense, strong and thin calcium-phosphate coating on commercial porous pure titanium implant surface in the light of a fast biomimetic procedure. After being polished, sandblasted, cleaned and treated with the mixture of HF and HNO3, the titanium plates were divided into two groups, namely group A and group B. The specimens of group A were free from any treatment. The specimens of group B were treated with the mixture of 48% H2SO4 and 18% HCl. All specimens soaked in SBF-A solution for 1d. Then the specimens were immersed in the SBF-B solution for 2 d. A thin calcium-phosphate coating was deposited on all the specimens of the two groups, the surface consisted of well-formed crystals, which were proved to be the mixture of hydroxycarbonated apatite (HCA) and octacalcium phosphate (OCP); the coating's Ca/P rate was 1.51. A thin carbonated calcium-phosphate coating was deposited on porous pure titanium by the use of the fast biomimetic procedure.

The effects of tensile strain and loading time on the secretion of IL-1 beta of human PDLF / 生物医学工程学杂志

This study aims at exploring the effects of tensile strain and loading time on the secretion of IL-1 beta of human periodontal ligament fibroblast. Five tensile strain values including 0%, 8%, 12%, 16%, 20% and three loading time including 24 h, 48 h, 72 h are set in this study. The prepared cell samples are mounted on the self-devised loading apparatus in vitro. The content of IL-1 beta in each sample was determined using double-antibody ELISA. The secretion amount of IL-1 beta per day is directly proportional to the loading time and tensile strain value in tensile strain group of 8%, 12%, 16%. The secretion amount of IL-1 beta reaches its maximum at tensile strain value of 16% in loading time groups. Loaded strain for 24 h and 48 h, the secretion amount of IL-1 beta at tensile strain value of 20% is obviously more than that at value of 0%, but the amount already begin to decrease apparently. Loaded strain for 72 h, the secretion amount of IL-1 beta decreases to a great extent that it is less than the amount at strain value of 0%. The tensile strain stimulates the secretion of IL-1 beta by human periodontal ligament fibroblast when the strain is under normal physiological extent, but the stimulation effect fades out as time goes on.