Dental follicles promote soft tissue management in surgical exposure of labially impacted maxillary canine.

BACKGROUND: The present study aimed to report a technically improved operation on the surgical exposure of labially impacted maxillary canine, elaborating the management of soft tissue to achieve better aesthetic results, and post-treatment periodontal health. METHODS: Patients sought orthodontic treatment with unilateral labially impacted maxillary canines were selected in this study. The impacted teeth were assigned to the experimental group and contralateral unimpacted canines were assigned to the control group. The impacted canines were surgically exposed with dissected dental follicle (DF) stitching to muscle and mucosa surrounding the crowns. The gingival index (GI), probing depth (PD), the width of the keratinized gingiva (WKG), gingival scars (GS), bone loss (BL), and apical root resorption (ARR) were recorded after the removal of the fixed appliance. A two-sample t-test was used for independent samples for parametric variables. RESULTS: A total of 24 patients with unilateral maxillary canine impaction were successfully treated. The outcomes of GI, WKG, GS, BL, and ARR did not indicate statistical significance between the experimental group and the control group. CONCLUSIONS: The preservation of DF promotes soft tissue management in combined surgical and orthodontic treatment of labially impacted maxillary canine to achieve better periodontal status. Trial Registration Chinese Clinical Trial Registry ChiCTR2000029091, 2020-01-12.

[Expert consensus on biomechanical research of dental implant].

Current biomechanical research of dental implants focuses on the mechanical damage and enhancement mechanism of the implant-abutment interface as well as how to obtain better mechanical strength and longer fatigue life of dental implants. The mechanical properties of implants can be comprehensively evaluated by strain gauge analysis, photo elastic stress analysis, digital image correlation, finite element analysis, implant bone bonding strength test, and measurement of mechanical properties. Finite element analysis is the most common method for evaluating stress distribution in dental implants, and static pressure and fatigue tests are commonly used in mechanical strength test. This article reviews biomechanical research methods and evaluation indices of dental implants. Results provide methodology guidelines in the field of biomechanics by introducing principles, ranges of application, advantages, and limitations, thereby benefitting researchers in selecting suitable methods. The influencing factors of the experimental results are presented and discussed to provide implant design ideas for researchers.

[Advances in titanium dental implant surface modification].

Titanium dental implants have wide clinical application due to their many advantages, including comfort, aesthetics, lack of damage to adjacent teeth, and significant clinical effects. However, the failure of osseointegration, bone resorption, and peri-implantitis limits their application. Physical-chemical and bioactive coatings on the surface of titanium implants could improve the successful rate of dental implants and meet the clinical application requirements. This paper reviews the characteristics of surface modification of titanium implants from the aspects of physics, chemistry, and biology. Results provide information for research and clinical application of dental implant materials.

[A review of peri-implant microbiology].

Dental implants represent the majority of treatment strategies used to replace missing teeth. However, peri-implant diseases caused by disturbance in peri-implant microbiological balance are among the reasons for implant failure. Since the 1980s, peri-implant microorganisms have been a hot research topic in dental microbiology. The bacterial ecology between the disease and health largely differs, which directly or indirectly increases the risk of peri-implant diseases. Accordingly, the determination of the 'core microbiome' of peri-implantitis and peri-implant mucositis is a key point of recent research.

[Influence of micro-pattern on adherence of graphite powder and three kinds of oral microbes].

OBJECTIVE: Trying to find out the mechanism of microstructure influencing bacterial adhesion, we prepared different microstructures to compare the adsorptive behavior of graphite powder and adhesive behavior of oral microbe. METHODS: We used polydimethylsiloxane (PDMS) to copy 23 microstructures of hydroxyapatite (HA) chip, and cultured them with different sizes graphite powder and oral microbes respectively, to observe and compare their behavior on microstructures. RESULTS: The adsorption of 30-50 microm powder on different microstructures was insignificant, while 10-20 microm powder had maximum adsorption on 10 microm and 20 microm microstructures. Saccharomyces albicans was most likely to adhere to 5 microm microstructures which was equivalent to its own size. However, microstructures had little effect on adhesion of Streptococcus mutans which grew in a chain. CONCLUSION: The size of microstructure was the most effective factor that affects the adsorption of non-living powder, and it also had the same effect on the microbial adhesion; but some special bacteria, such as Streptococcus mutans which grew in a chain, was not affected by the sizes or shapes of microstructures.

[The experimental study on biodegradable gel membrane applied to prevention of postoperative adhesion of abdominal cavity surgery].

OBJECTIVE: To develop a new type of anti-adhesion gel membrane and explore its applying technique. METHODS: 24 adult New Zealand white rabbits were used for the experiment research project, the animals were divided into two groups: the experiment group (18 adult New Zealand white rabbits) and the control group (6 adult New Zealand white rabbits). The animal models were established via the abdominal cavity. The biodegradable gel membrane was covered to the surface of the operating region in experimental animal group, while the 0.9% NaCL was directly rinsing the operating region in the controlled group. The specimens were collected at postoperatively week 2, 4 or 8 respectively. The samples were evaluated by global and histological observation. RESULTS: In the experiment group, a few adhed zones were observed in 2 and 4 weeks after operation, but in 8 weeks after operation, the adhesion zone was disappeared. In the control group, a few adheol zones were founded in 2 weeks after operation. In 4 weeks after operation, the adhed zone become conspicuously emerged. In 8 weeks after operation, the cicatri band was occurred. CONCLUSION: The biodegradable gel membrane usd into the postoperative abdominal cavity is effective and easy to manipulate, and it could be used as a high-effect, cheap drug of anti-adhesion in operation for surgeons.