Development of a novel three-dimensional injection guide for trigeminal ganglia.

BACKGROUND: Trigeminal ganglion (TG) plays an important role in the process of orthodontic pain. It's necessary to design an accurate, precise and minimally invasive trigeminal ganglion injection guide plate to study TG. METHODS: Micro-CT was used to obtain the Dicom format data, and three-dimensional (3D) software (mimics and magics23.03) was used to reconstruct 3D head models. Design and modifications of the TG injection guide plate were performed in Magic 23.03 software, and the guide plate was produced by a 3D stereolithography printer. X-ray, micro-CT, Evans blue, and virus transduction were used to demonstrate the accuracy of the guide-assisted injection. Pain levels were evaluated after using the injection guide by a bite force test and Von Frey test. RESULTS: X-ray and micro-CT tests confirmed that the injection needle reached the bilateral trigeminal ganglia fossa. The Evans blue test and virus transduction proved that the injected drug could be accurately injected into the bilateral trigeminal ganglion and the lentivirus could be successfully transfected. The percentage of accurate injection was 10/10 (bilateral trigeminal ganglia). Orofacial pain induced by the trigeminal ganglion injection was mild and returned to baseline within seven days. CONCLUSION: The injection guide described in this study is viable and reliable for the delivery of drugs and virus transduction into the trigeminal ganglia.

Multifocal epithelial hyperplasia confined to the interdental papilla of an adult Chinese man: a rare case report and literature review.

BACKGROUND: Multifocal epithelial hyperplasia (MEH), or focal epithelial hypertension (FEH), or Heck's disease, is an uncommon, benign oral mucosal disease associated with human papillomavirus infection. It is mostly observed in indigenous populations of the world, and has been rarely reported in China. However, previous research suggested there might be a greater prevalence of MEH in the Chinese population. While predominantly involves the lips, buccal mucosa and tongue, MEH was occasionally reported to affect the hard palate and gingiva as well. CASE PRESENTATION: This paper reports a case of extensive MEH lesions that confined to the interdental papilla of a Chinese male without detection of HPV, and summarizes the published gingiva-involved MEH reports from 1966 until present. The lesions were excised with an Er: YAG laser after scaling and root planning, no recurrence was observed after 6-month follow-up. CONCLUSIONS: The present report illustrates the need for clinicians to be aware of rare presentations of MEH to facilitate a prompt diagnosis and proper management. More reports are encouraged to determine a correct prevalence rate of MEH in China.

Clinical effect of Nobel Biocare angulated screw channel crown compared with cement crown in the aesthetic area: A retrospective cohort study with a mean 32 months follow-up (range 12 to 70 months).

OBJECTIVE: The objective of this study is to compare the clinical efficacy of angulated screw channel abutment applied in the anterior area with regular cemented crowns. MATERIALS AND METHODS: Forty-eight patients were included and divided into two groups: the angulated screw channel group (ASC) and regular cemented group (RC) in this retrospective cohort study. The evaluation criteria included implant/restoration survival rate, keratinized mucosa width (KMW), bleeding on probing rate (BOP%), probing depth (PD), pink aesthetic score (PES), mechanical/biological complications, emergence angle (EA), the site of implant axis penetrate (SA), marginal bone loss (MBL), and buccal bone thickness (BBT) at 0 mm, 1 mm, 3 mm, 5 mm below the implant shoulder were evaluated in immediate postoperative (T0) and follow-up period (T1). RESULTS: This retrospective cohort study included a total of 48 patients, with a mean 32 months follow-up period range from 12 months to 70 months. The study did not find any cases of implant failure or restoration failure. EA was significantly wider in the RC group than ASC group (RC: 33.53° ± 8.36° vs ASC: 27.43° ± 8.08°, p = 0.016*). While the BOP% was statistically significant higher in the RC group than ASC group (RC: 28.35% ± 22.92% vs ASC: 13.18% ± 20.00%, p = 0.027*). No significant differences were observed in the other measurements of comparison. CONCLUSION: Within the limitations of the study, angulated screw channel (Nobel Biocare) crowns might allow the implant axis aim at incisal edge to reduce the emergence angle in the anterior area and benefit the soft-tissue during the 12-70 months follow-up period.

Implications of occlusal plane in diagnosis and treatment of malocclusion. / 平面对错 畸形诊断和治疗的意义.

Occlusal plane (OP) is one of the essential factors affecting craniofacial morphology and function. The OP not only assists in diagnosing malocclusion but also serves as an important reference for making treatment plans. Patients with different types of malocclusions have different forms of OP. Compared with patients with standard skeletal facial type, the occlusal plane of patients with skeletal class Ⅱ and high angle is steeper, while that of patients with skeletal class Ⅲ and low angle is more even. In orthodontic treatment, adjusting and controlling the OP can promote the normal growth and development of the mandible in most patients with malocclusion during the early stage of growth, while causing favorable rotation of the mandible in some adults with mild-to-moderate malocclusion. For moderate-to-severe malocclusion, the OP rotation by orthodontic-orthognathic treatment can achieve better long-term stability. This article reviews the evolution of the definition of OP and its implications for diagnosing and the guiding treatment of malocclusion.

Rapid maxillary expansion treatment increases mid-facial depth in early mixed dentition.

Objective: To evaluate the effects of rapid maxillary expansion (RME) on mid-facial depth in early mixed dentition and to investigate the relationship between change in mid-facial depth and maxillary sinus and nasal cavity. Methods: A total of 35 patients with mixed dentition treated with a Haas expander were included in this retrospective study. All patients underwent a cone-beam computed tomography scan before and after rapid maxillary expansion. The Wilcoxon signed-rank test was performed to evaluate the changes in maxillary width, facial depth, maxillary sinus, and nasal cavity volume before and after expansion. Multiple linear regression analysis was applied to evaluate the correlations among them. Results: The hard and soft tissue facial depth in the middle third increased significantly (P < 0.001). The gain on the outer sagittal plane (1.04-1.52 mm) was slightly bigger than that on the inner sagittal plane (0.91-1.30 mm). Maxillary width and nasal cavity width increased 3.42 ± 0.93 mm (P < 0.001) and 2.25 ± 0.77 mm (P < 0.001), respectively, after treatment. A gain was also achieved in both nasal cavity volume (2,236.15 mm3, P < 0.001) and maxillary sinus volume (1,227.33 mm3, P < 0.001). Multiple linear regression analysis showed that with the increase in maxillary sinus volume, the facial depth increased as well (B = 0.455-0.683, P < 0.05). Also, statistically significant correlations were found between nasal width and nasal cavity volume (B = 0.384, P < 0.05). Conclusion: The depth of the middle third face increased significantly. The facial depth increase was related to the enlargement of maxillary sinus volume, while the nasal cavity volume gain was related to the nasal width increase. This indicated that RME might enhance the fullness of the mid-face and facilitate the patency of nose breathing.