Special diffusion pathway of pericoronitis of the third molar: A case report and literature review.

INTRODUCTION: Pericoronitis of wisdom teeth along the jaw diffusion may be a rare diffusion pathway, which can cause osteomyelitis and maxillofacial space infection serious complications. PRESENTATION OF CASE: A 62-years-old male patient presented with swelling and discomfort of the right cheek for more than 1 year. The patient was previously healthy and denied various systemic medical histories. The patient's face was asymmetric, the right cheek was swollen, and the depressed edema was seen on the surface of the masseter area of the right parotid gland. Based on the preoperative cone-beam computed tomography (CBCT) imaging results, the initial diagnosis was: centralized osteomyelitis of the jaws. The surgical plan was minimally invasive extraction 48 and localized debridement of the lesion area. After three months of follow-up, the patient's symptoms were significantly improved without recurrence. DISCUSSION: Pericoronitis of wisdom teeth along the jaw diffusion is a rare diffusion pathway, which can lead to secondary jaw osteomyelitis, the treatment of which consists of lesion debridement, dead bone curettage and antibiotic therapy. CONCLUSION: Through literature review and summary of the diagnosis and treatment process of this case, such cases should be diagnosed as early as possible and conservative treatment should be actively used to avoid the occurrence of complications. In addition, the special diffusion pathway of this case may provide a new theoretical basis for the source of infection of central jaw osteomyelitis.

A Rare Case of Concrescence of Mandibular Third Molar and Supernumerary Fourth Molar.

Concrescence reveals a rare developmental anomaly in which two fully formed teeth are joined along the root surfaces by cementum, and generally occurs in maxillary molars, especially in a third molar and a supernumerary tooth. Very few cases have been reported about the concrescence of a third molar and a supernumerary fourth molar. Based on our available knowledge, this case report described a rare presentation in which concrescence is observed between a third molar and a supernumerary fourth molar in the mandible by diagnosing with cone-beam CT and histological examination.

Differences in Supragingival Microbiome in Patients with and without Full-Crown Prostheses.

Objectives: To characterize the microflora profile of supragingival biofilm in patients with and without full-crown prostheses. Methods: Plaque samples of full-crown prostheses and teeth in patients with porcelain-fused-to-metal crowns, all-ceramic crowns, and no prostheses were collected (three patients per group), using 16S rRNA high-throughput sequencing technology to conduct DNA sequencing on the samples and using Qiime, R, and PICRUSt2 software to perform bioinformatics analyses and functional analyses on sequencing data. Results: In total, 110,209 valid sequences were obtained in the experiment, corresponding to 11 phyla and 120 genera. The predominant species shared by the three groups were phyla Actinobacteria, Bacteroidetes, Firmicutes, Fusobacteria, and Proteobacteria and genera Rothia, Porphyromonas, Prevotella, Streptococcus, Veillonella, Leptotrichia, Neisseria, Citrobacter, and Pseudomonas. The species-difference analysis showed that genus Hameophilus significantly increased after the patient wore the dental prosthesis. Compared with the no-prosthesis samples, the functional analysis showed that cell motility increased in the samples from full-crown prostheses, while replication and repair, and translation decreased. Conclusions: This study reveals the changes in the oral microbial community of patients with full-crown prostheses, which could provide insights regarding the safety of materials for long-term use in the oral cavity.

[Study on alveolar ridge augment through technique combination of implant-retented titanium lattice with decalcified dental matrix implanting].

OBJECTIVE: To evaluate the effect of technique combination of implant-retented titanium lattice with decalcified dental matrix (DDM) implanting. METHODS: Six healthy male dogs (weighing of 10-20 kg) were randomly divided into 3 groups. All the premolars were extracted on both sides of the jaw in dogs. After 2 weeks, titanium lattice and implant were implanted in the maxillary premolar region with DDM on one side (experimental group), but without on the other side (control group) of each dog. After 4, 9 and 14 weeks, respectively, 2 animals were individually killed each time, and the samples were evaluated by general observation, X-ray examination, histological observation and histomorphometric analyses. RESULTS: General observation: Among the 6 dogs, there was no postoperative infection or death. The X-ray examination showed that the bone density of the experimental group was greater than the control group at 4 and 9 weeks, and had no significant difference as to the vicinity bone at 14 weeks. On the other hand, the density of the control group was very low under the titanium lattice and around the implant. The experimental group revealed a ridge augment of (1.93 +/- 0.24) mm, and control group (-1.02 +/- 1.20) mm (P < 0.05). Developed bone sponge could be found after 14 weeks. Histological observation showed that in the experimental group, the DDM surface was nearly absorbed at 4 weeks. A few new bones were formed at 9 weeks. The whole DDM was absorbed; the trabecular bone was thick and arranged regularly; and the intergradations of implant were observed at 14 weeks. In the control group, there were some inflammatory fibers around the neck of implant at 4 weeks. The inflammatory condition extended to the root of implant and the titanium lattice at 9 weeks. There was no newly-formed bone under the titanium lattice at 14 weeks. Histomorphometric analyses showed that the implant contact bone ratio approached 1:1, and showed no significant difference between the new bone fragment and former bone fragment in the experimental group. CONCLUSION: This augmentation of alveolar ridge evaluated by the study is applicable, but further study is necessary.