Combined micro-apical surgery and vital pulp therapy in mandibular second molars with external root resorption caused by impacted teeth / 华西口腔医学杂志

OBJECTIVES@#This study aimed to establish a new treatment of the mandibular second molars with external root resorption caused by impacted teeth to preserve the affected teeth and their vital pulps.@*METHODS@#For mandibular second molars clinically diagnosed as external root resorption caused by impacted teeth, debridement and removal of the root at the resorption site via micro-apical surgery and direct capping of the pulp with bioactive material on the surface of the root amputation via vital pulp therapy were performed immediately after the impacted teeth were extracted.@*RESULTS@#The external root resorption of the affected tooth was ceased. It was asymptomatic with intact crown, normal pulp, periapical alveolar bone reconstruction, normal periodontal ligament, continuous bone sclerosis, and no periapical translucency in radiographic examination at the 1-year postoperative follow-up, thus showing good prognosis.@*CONCLUSIONS@#Simultaneous combination of micro-apical surgery and vital pulp therapy after extraction of impacted teeth could successfully preserve mandibular second molars with ERR caused by impacted teeth and their vital pulps.

The Role of SDF-1α-CXCR4/CXCR7 in Migration of Human Periodontal Ligament Stem Cells

Background and Objectives@#Regenerative endodontic procedures (REPs) are a research hotspot in the endodontic field. One of the biggest problems of REPs is that it is difficult to realize regeneration of pulp-dentin complex and functional reconstruction. The reason is still not clear. We hypothesize that the migration may be different in different dental stem cells. Periodontal ligament stem cells (PDLSCs) may migrate faster than stem cells of apical papilla (SCAPs), differentiating into cementum-like tissue, bone-like tissue and periodontal ligament-like tissue and, finally affecting the outcomes of REPs. Hence, this study aimed to explore the mechanism that regulates the migration of PDLSCs. @*Methods@#and Results: After isolating and culturing PDLSCs and SCAPs from human third molars, we compared the migration of PDLSCs and SCAPs. Then we investigated the role of SDF-1α-CXCR4/CXCR7 axis in PDLSC migration. We further investigated the impact of Porphyromonas gingivalis (P. gingivalis) lipopolysaccharide (LPS) on PDLSC migration and the potential mechanism. PDLSCs showed better migration under both noninflammatory and inflammatory conditions than SCAPs. SDF-1α can promote the migration of PDLSCs by elevating the expression of CXCR4 and CXCR7, increasing the interaction between them, promoting expression of β-arrestin1 and activating the ERK signaling pathway. P. gingivalis LPS can promote the migration of PDLSCs toward SDF-1α through increasing the expression of CXCR4 via the NF-κB signaling pathway, promoting the expression of β-arrestin1, and activating the ERK signaling pathway. @*Conclusions@#This study helped elucidate the potential reason for the difficulty in forming pulp-dentin complex.

Berberine mediates root remodeling in an immature tooth with apical periodontitis by regulating stem cells from apical papilla differentiation / 国际口腔科学杂志·英文版

Once pulp necrosis or apical periodontitis occurs on immature teeth, the weak root and open root apex are challenging to clinicians. Berberine (BBR) is a potential medicine for bone disorders, therefore, we proposed to apply BBR in root canals to enhance root repair in immature teeth. An in vivo model of immature teeth with apical periodontitis was established in rats, and root canals were filled with BBR, calcium hydroxide or sterilized saline for 3 weeks. The shape of the roots was analyzed by micro-computed tomography and histological staining. In vitro, BBR was introduced into stem cells from apical papilla (SCAPs). Osteogenic differentiation of stem cells from apical papilla was investigated by alkaline phosphatase activity, mineralization ability, and gene expression of osteogenic makers. The signaling pathway, which regulated the osteogenesis of SCAPs was evaluated by quantitative real time PCR, Western blot analysis, and immunofluorescence. In rats treated with BBR, more tissue was formed, with longer roots, thicker root walls, and smaller apex diameters. In addition, we found that BBR promoted SCAPs osteogenesis in a time-dependent and concentration-dependent manner. BBR induced the expression of β-catenin and enhanced β-catenin entering into the nucleus, to up-regulate more runt-related nuclear factor 2 downstream. BBR enhanced root repair in immature teeth with apical periodontitis by activating the canonical Wnt/β-catenin pathway in SCAPs.

Clinical management and prognosis evaluation of pulp regeneration therapy / 中华口腔医学杂志

Pulp regeneration in a tooth with pulp necrosis is the research hotspot in current clinical treatment of endodontic diseases. Up to now, the revascularization therapy, which is one of the regenerative endodontic treatment, and the most extensive and effective method in clinical practice, can partially achieve the goal of pulp regeneration and root development in young permanent immature teeth. In order to standardize the technique and improve the curative effect, this atticle discusses the indications, pre-treatment preparation, treatment procedure and the rapeutic evaluation of pulp revascularization therapy.

Clinical management of the intentional tooth replantation / 中华口腔医学杂志

Intentional tooth replantation is the last resort for saving natural teeth in treatment of the endodontic diseases. In order to promote the utilization, standardize the operation and improve the success rate of this treatment, this review suggests the indication, discusses the key points of the surgical procedure, proposes the path of the diagnosis and the treatment protocol of the intentional replantation.

Vital pulp therapy of damaged dental pulp / 华西口腔医学杂志

The development of an expert consensus on vital pulp therapy can provide practical guidance for the improvement of pulp damage care in China. Dental pulp disease is a major type of illness that adversely affects human oral health. Pulp capping and pulpotomy are currently the main methods for vital pulp therapy. Along with the development of minimal invasion cosmetic dentistry, using different treatment technologies and materials reasonably, preserving healthy tooth tissue, and extending tooth save time have become urgent problems that call for immediate solution in dental clinics. This paper summarizes the experiences and knowledge of endodontic experts. We develop a clinical path of vital pulp therapy for clinical work by utilizing the nature, approach, and degree of pulp damage as references, defense and self-repairing ability of pulp as guidance, and modern technologies of diagnosis and treatment as means.

Confusion and solution for vital pulp therapy / 华西口腔医学杂志

Dental pulp tissue plays a role in forming dentin, providing nutrition, conducting pain, and generating protective responses to environmental stimuli. Bacterial infection is the main cause of pulp disease, where histopathological changes are the histological basis for determining the choice of treatment and the evaluation of therapeutic effect. Thus, particular attention should be given to eliminate infection, as well as preserve and maintain pulpal health in teeth that show reversible or limited pulpal injuries. Vital pulp therapy, especially its indications and prognostic factors, has been a research hotspot that often causes confusion among clinicians. In this paper, we briefly introduce the confusion and solution for vital pulp therapy in terms of indications, pulp condition assessment, infection elimination, and capping material selection. In addition, we develop a clinical pathway and an operation normalization of vital pulp therapy to better perform the therapy.

Confusion and solution for root canal working length determination / 华西口腔医学杂志

Pulpitis and periapical periodontitis is a type of bacterial infectious disease, and bacteria frequently plant in the entire root canal system during the terminal stage. Main clinical treatment strategy of the disease requires root canal therapy, a key and core procedure for the successful treatment by thoroughly removing the root canal infection. The premise and guarantee of thoroughly removing root canal infection is by determining the accurate root canal working length. However, introduction of the complexity of the apical root anatomical structure, the confusion in determining the position of apical stop, and the method to determine the root canal working length. methods of accurately determining root canal working length, especially determining the position of apical stop, has been a hot topic among endodontic specialists, frequently causing confusion among many clinicians. This review provides a brief

Clinical investigation of radix entomolaris in mandibular first molars / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the prevalence and treatment of radix entomolaris (RE) in mandibular first molars.</p><p><b>METHODS</b>378 cases of mandibular first molars with root canal therapy were collected. The case included clinical records and periapical radiographs of preoperative, intraoperative and postoperative. The root number, root canal number and root canal therapy were investigated.</p><p><b>RESULTS</b>The RE prevalence of mandibular first molars was 26.98% (102/378). Both gender and bilateral occurrence of RE did not show a significantly difference (P>0.05), but there was a significantly greater incidence of instrument separation, lateral perforation and underfill of the root canals in RE than other canals in mandibular first molars (P<0.05).</p><p><b>CONCLUSION</b>The RE prevalence of mandibular first molar is high and there is a significantly greater incidence of instrument separation, lateral perforation and underfill of the canals in RE than other canals in mandibular first molars.</p>

Assessment of referral cases for root canal therapy / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To assess referral cases for root canal therapy to provide clinical evidence with establishment of referral system.</p><p><b>METHODS</b>A questionnaire was designed to collect 312 cases (355 teeth) referred to Department of Conservative Dentistry and Endodontics, West China School of Stomatology, Sichuan University for root canal therapy from April to June in 2011. The questionnaire consisted of questions such as age, gender, occupation, general disease and medical histories of patients, sources. Difficulty of treatment before therapy and reasons for referral were evaluated.</p><p><b>RESULTS</b>In 355 referral teeth, the most were mandibular first molars (17%), the greatest percentage of reasons were calcified root canals (30%), the second was root canal retreatment (24%). 72% of teeth belong to the complicated difficulty (Class III), while 7% were listed as the uncomplicated difficulty (Class I). No significantly difference from different sources was found (P = 0.9).</p><p><b>CONCLUSION</b>Establishment of referral system needs cooperation with every dentist. Difficulty of cases for root canal therapy before treatment should be first evaluated to treat or to refer. Referral cases for root canal therapy should be treated by endodontist of corresponding level according to the difficulty.</p>

Trachea-bronchoplasty in the treatment of centrally located lung cancer / 中国肺癌杂志

<p><b>BACKGROUND</b>To maximize the preservation of functional pulmonary parenchyma and improve the quality of life of patients with centrally located lung cancer, trachea-bronchoplasty has been used in clinical application with good efficacy. The aim of this study is to explore the appropriate admission and management of trachea-bronchoplasty and prevent complications of trachea-bronchial sleeve resection in the treatment of centrally located lung cancer.</p><p><b>METHODS</b>Seventy-six patients with central lung cancer, who were treated with trachea-bronchoplasty from June, 1988 to October, 2004, were analyzed. There were 49 cases of squamous cell carcinoma, 16 adenocarcinoma, 7 adenosquamous carcinoma, 3 small cell lung cancer and 1 adenoid cystic adenocarcinoma. Seventeen patients were in stage I, 39 in stage II, 17 in stage IIIA and 3 in stage IIIB. There were 55 cases of sleeve lobectomy, 12 lobectomy with wedge resection of the main bronchus, 8 big arc resection of superior lobar bronchus-main trachea-lateral wall of trachea, 1 resection of right upper lobe-right main bronchus-carina-lateral trachea and carinal reconstruction.</p><p><b>RESULTS</b>Postoperative complications happened in 7 patients. Pneumonia and atelectasis occurred in 6 cases, in which 1 died of heart and respiratory failure. Another one died of haemorrhage of upside alimentary canal. Seventy-one patients were followed up (93.4%). The 1-, 3-, 5-year survival rate was 82.4% (56/68), 57.8% (26/45) and 41.7% (15/36) respectively.</p><p><b>CONCLUSIONS</b>The trachea-bronchoplasty can not only preserve functional pulmonary parenchyma as much as possible and improve the quality of life of patients, but also provide an operative opportunity to those patients with poor pulmonary function in the treatment of centrally located lung cancer.</p>

Contribution of radiogram in diagnosis of primary vertical root fracture in mandibular first molar / 实用口腔医学杂志

0.05 ). The assessments of the 4 examiners were uniform(?=0.57~0.65).Conclusion:Radiograph can provide essential evidence for the clinical diagnosis of the vertical root fracture in mandibular first molar.

In vitro study of the anatomy of 80 maxillary first permanent molars / 实用口腔医学杂志

Objective:To study the anatomy of the maxillary first permanent molars. Methods:Macrography was used to observe the morphology of the mesiobuccal root,the degree of abrasion,the morphology of the floor of pulp cavity, the number and type of apical foramen.Vernier was used to measure the length indexes and the distance from the apical foramen to the tip of the root.Clearing technique was used to investigate the root canal systems. Results:26.9% of mesiobuccal root had type III apical foramen,56.25% of mesiobuccal root had two canals,7.5% teeth had three root canals. Conclusions: The maxillary first permanent molar has a high ratio of more than one root canal in mesiobuccal root(63.75%).

The effect of radiation of Nd:YAC laser on sealing ability in retrograde filling / 实用口腔医学杂志

Objective:To discuss the effect of radiation of Nd:YAG laser in apical retrograde filling. Methods: 50 similar roots were randomly divided into 5 groups.The anatomical crowns were removed at the cementoenamel junction and the remaining roots were treated endodontically with conventional methods before the apical 2 mm were cut and a dish-like hole made in the cutting surface by high speed round bur. Except the first group,each hole were radiated by the Nd:YAG laser for different time or with different patterns and after that,the glass ionomer cement were retrofilled into the hole. A microleakage measurements were carried out and the result were measured and recorded. The hole surface was also observed under electron microscopy. Results:The leakage of the groups with Nd:YAG radiation were decreased significantly(P