Clinical study of age-related sensory innervation of the anterior hard palate / 华西口腔医学杂志

OBJECTIVES@#The present study aimed to explore the innervation of the anterior hard palatine and its relationship with individual development stage. Specifically, the effects of anesthesia on patients of different ages were observed, and neurodevelopment in the maxillofacial region was invesitgated. References that are helpful in selecting local anesthesia were provided.@*METHODS@#A total of 182 patients with mixed dentition were randomly divided into the nasopalatine nerve block and greater palatine nerve block groups. Then, 219 patients with permanent dentition were divided into an adolescent group (13-18 years old) and adult group (over 19 years old), all of whom underwent bilateral greater palatine nerve block. Palatal mucosal pain sensation was tested pre- and post-anesthesia with Von Frey hairs.@*RESULTS@#Among the children with mixed dentition, bilateral greater palatine nerve block tended to result in better anesthetic effects than nasopalatine nerve block (@*CONCLUSIONS@#The sensation of the anterior hard palatine seems mainly dominated by the greater palatine nerve until mixed dentition and gradually shifted to the nasopalatine nerve in conjunction with maxillary development and tooth replacement. Hence, the innervation of the anterior hard palatine induce a secondary development during the development of the maxilla.

Prognosis of teeth with external root resorption caused by adjacent impacted teeth / 华西口腔医学杂志

OBJECTIVE@#This study aimed to investigate the prognosis of permanent teeth with external root resorption (ERR) caused by adjacent impacted teeth.@*METHODS@#A total of 75 ERR teeth (permanent teeth) caused by adjacent impacted teeth of 63 patients were included. The prognosis of ERR teeth was analyzed followed by minimally invasive extraction of the adjacent impacted teeth. The time of follow-up was six months. The relationship between prognosis of ERR teeth and patients' age, gender, root number, type of root resorption and degree of root resorption were analyzed.@*RESULTS@#In the 75 ERR teeth, 67 teeth (89.3%) did not show pulpitis symptoms. The clinical outcome was found to be related with age (r=0.330, P0.05). Pulpitis symptom was not found in ERR teeth of patients under 30 years old.@*CONCLUSIONS@#For ERR teeth caused by adjacent impacted teeth, keeping the pulp vital after surgical removal of impacted teeth is highly probable. Post-operative follow-up instead of preventive root canal therapy of ERR teeth is recommended.

Research progress on the modification of guided bone regeneration membranes / 华西口腔医学杂志

Guided bone regeneration (GBR) is an important technique to solve bone defect problems. In this technique, GBR barrier membranes play an irreplaceable role. GBR membranes can act as a barrier protecting fibroblasts from bone defects and promote osteoblast adhesion and proliferation, leading to bone regeneration. GBR barrier membranes should be enhanced because of the disadvantages of collagen membranes, which are extensively applied to the field of GBR. Therefore, various efforts have been devoted to modifying the antibacterial and osteogenic properties of GBR barrier membranes and developing novel materials. This article reviews the research advancements on the modification of GBR barrier membranes and discover future directions for the development of GBR barrier membranes to provide a reference for bone tissue engi-neering and repair.

Relationship between initial archwire materials and pain at the initial stage of orthodontic treatment: a systematic review and network Meta-analysis / 华西口腔医学杂志

<p><b>OBJECTIVE</b>This review aims to assess the relationship between initial archwire materials and pain at the initial stage of orthodontic treatment.</p><p><b>METHODS</b>On October 1, 2017, seven databases were searched electronically for studies oninitial archwire materials and pain at the initial stage of orthodontic treatment. Quality assessment was performed with bias risk assessment tools suggested by Cochrane's handbook. Data extraction of included studies was also carried out. Network Meta-
analysis was conducted using R 3.4.2 (with JAGS 4.3.0), GeMTC 0.14.3, and STATA 11.0.</p><p><b>RESULTS</b>Five studies with 330 participants were included, comparing four different materials: multi-stranded stainless steel, conventional nickel-titanium, super-elastic nickel-titanium, and thermal heat-activated nickel-titanium. Two studies were at low risk of bias, one was at high risk of bias, and the remaining two were at unclear risk of bias. Network Meta-analysis results showed no statistical differences of pain among the four initial archwire materials at day 1 and day 7. However, the most painless material was most likely to be thermal heat-activated nickel-titanium on rank probability.</p><p><b>CONCLUSIONS</b>On statistical probability, thermal heat-activated nickel-titanium initial arch wires is most likely to cause the least pain at the initial stage of orthodontic treatment, compared with other materials.</p>