Effects of different pH conditions on ffh gene expression in Streptococcus mutans / 华西口腔医学杂志

<p><b>OBJECTIVE</b>This research aimed to detect the expression levels of ffh gene in Streptococcus mutans (S. mutans) UA159 under different pH conditions, analyze the effect of pH on the expression of ffh gene in S. mutans, and identify the factors regulating the ffh gene expression.</p><p><b>METHODS</b>Samples of S. mutans were collected at different growth stages (4 h, 18 h) and pH values (pH 4.0-7.0). Fluorescence quantitative real-time polymerase chain reaction (qRT-PCR) was used to measure the relative mRNA expression and trend of the target gene ffh in S. mutans at different growth stages and pH values.</p><p><b>RESULTS</b>qRT-PCR results showed that the ffh gene expression decreased along with pH at 4 h, but the expression increased with decreasing pH at 18 h. Under the same pH conditions, the ffh gene expression was significantly different between 4 h and 18 h (P < 0.05).</p><p><b>CONCLUSION</b>Growth stage and pH value influenced the ffh gene expression in S. mutans.</p>

Application of surgical navigation technology in the treatment of zygomatic fracture / 华西口腔医学杂志

Zygomatic fracture is one of the most common mid-facial fractures. Zygomatic fracture often leads to open-mouth and chewing dysfunctions, which are often associated with pronounced zygomatic facial deformity, causing psychological and physiological problems in patients. The complicated anatomical structures associated with zygomatic fracture often make treatment difficult. Surgical navigation technology provides a new auxiliary method for improving the treatment results for zygomatic fracture. This review aims to provide a comprehensive overview of the application of surgical navigation technology in the treatment of zygomatic fracture.

Progress of temporomandibular joint prosthesis / 华西口腔医学杂志

The anatomically and functionally complex nature of the temporomandibularjoint (TMJ) makes its reconstruction one of the most challenging tasks faced by surgeons who operate in the head and neck. TMJ prosthesis is one of the important techniques in the reconstruction of TMJ. The main indications for TMJ prosthesis include ankylosis, fractures of condylar that can't be fixed, trauma or tumor, end-stage TMJ disturbance, and TMJ dysplasia caused by Hallermann-Streiff syndrome. TMJ replacement aims to enhance the function of TMJ, alleviate pain, and prevent serious complications. TMJ prosthesis is advantageous in oral and maxillofacial surgery because it can imitate normal anatomic morphology and adhere to the host. Moreover, the use of other materials is no longer necessary and functional training can be started postoperatively at once, among others. Prosthetic materials have leading and promoting functions in the development of joint prosthesis. Good design, fit shape, and fixation are the necessary conditions for prosthesis to serve its function. Investigation of joint biomechanics is also necessary. With the rapid developments in material science, joint biomechanics, and other related subjects, TMJ prosthesis has been significantly improved in terms of its materials, design, fit shape, and fixation techniques. In addition, the development of TMJ prosthesis would expand its applications. This review intends to provide an overview about the progress and clinical application of TMJ prosthesis.