Assessment of oral emergency services during COVID-19: a retrospective study of 14,885 cases in Shanghai.

BACKGROUND: To assess the impact of coronavirus disease-2019 (COVID-19) in its outbreak stage (Spring Festival in 2020) on oral emergency services. METHODS: Oral emergency cases in Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, during the Spring Festival after the outbreak of the COVID-19 epidemic in 2020 were collected and compared with those in 2018 and 2019. Electronic medical records including the visited department, age, sex, time, date, region, and diagnosis were collected and analyzed. The results were statistically analyzed using Pearson's Chi-square test and one-way analysis of variance (ANOVA). RESULTS: Compared with that in 2018 and 2019, the total number of patients decreased during the Spring Festival in 2020 (p < 0.001), but the proportions of patients visiting Oral Surgery and Oral, Head, and Neck Oncology Emergency departments increased. The average age of patients increased, and the number of night visits decreased. Toothache diseases involving endodontic and periodontal diseases increased, while the proportion of maxillofacial trauma decreased. The wasn't a linear association between diagnosis or genders (P > 0.001) across years. However, a linear-by-linear association between age groups and years, visited departments and years were observed (P < 0.001). CONCLUSIONS: The study revealed that the transmission of COVID-19 affected the patient population and structure of disease types and oral services in 2020 during the Spring Festival, compared with those in the previous two years. The visits to oral emergency departments and the proportions of patients who were children and adolescents reduced; meanwhile, the percentage of the elderly people increased during the outbreak of COVID-19. The clear trend of age groups and visiting divisions could be used as a marker to reflect the severity of the COVID-19 pandemic. These results may serve as a reference for dental practitioners involved in oral emergency services and to allocate the limited emergency health resources.

[The risk and prevention of bio-aerosol transmission in dental clinics].

Corona virus disease 2019 (COVID-19) has become a Public Health Emergency of International Concern since its outbreak, and whether COVID-19 can transmit by aerosol remains controversial. The problem of bio-aerosol transmission in the relatively confined dental clinics has aroused wide attention in the field of dentistry. This review provided a most updated summary on the relation between bio-aerosols and dental clinics, which included the microorganisms in bio-aerosols, the bio-aerosol transmission and the sources testing methods, temporal and spatial distribution of dental bio-aerosols and summarized how to reduce the exposure to bio-aerosols in dental clinics.

[Clinical evaluation for coronectomy of the impacted mandibular third molars in close proximity to inferior alveolar nerve].

PURPOSE: To evaluate the outcome of coronectomy for management of impacted mandibular third molars in close proximity to inferior alveolar nerve (IAN). METHODS: Ten patients with impacted mandibular third molars which approached or was close to the inferior alveolar nerve diagnosed on panoramic film and cone-beam CT (CBCT) scan were included in the study. Coronectomy was conducted at the cemento-enamel junction, leaving the roots below the alveolar crest and primary closure was performed. After the root apex was pushed away from the inferior alveolar nerve, the impacted lower third molar was then removed. RESULTS: Ten patients had little post-operative pain and swelling, none of them had IAN injury or infection. Only 1 patient was failed to move the roots away from IAN and the roots were left in the alveolar socket, but without any symptoms and side effects during 1 year of follow-up. CONCLUSIONS: Coronectomy is effective in controlling inferior alveolar nerve injury following third molar surgery in radiographically evaluated high risk cases and it has very low incidence of complications.

Effect of Lactobacillus acidophilus and Porphyromonas gingivalis on proliferation and apoptosis of gingival epithelial cells.

PURPOSE: This study aimed to evaluate the possible antagonistic effects of Lactobacillus acidophilus on Porphyromonas gingivalis, and detect inhibition of Lactobacillus acidophilus on Porphyromonas gingivalis when they are co-cultured with human gingival epithelial cells. MATERIALS AND METHODS: Human gingival epithelial cells were co-cultured with Lactobacillus acidophilus and Porphyromonas gingivalis alone or together. The amount of Porphyromonas gingivalis adhering to or invading the epithelial cells were determined by bacterial counts. The cellular proliferation was assayed by the MTT method. Apoptosis was detected by flow cytometry with apoptosis detection kit. RESULTS: On one hand, Lactobacillus acidophilus reduced the inhibitory effect of Porphyromonas gingivalis on the human gingival epithelial cells proliferation in a dose dependent manner. On the other hand, Porphyromonas gingivalis induced significant apoptosis on human gingival epithelial cells, and Lactobacillus acidophilus inhibited this apoptosis-inducing effect of Porphyromonas gingivalis in a dose dependent manner. CONCLUSIONS: Porphyromonas gingivalis inhibits the proliferation and induces the apoptosis of human gingival epithelial cells. Lactobacillus acidophilus could attenuate this effect in a dose-dependent manner, and it thus reduces the destruction from pathogens. Lactobacillus acidophilus could be an effective candidate for probiotic therapy in periodontal diseases.

[Clinical management of calcified root canal with Mtwo NiTi files].

PURPOSE: To evaluate the effect of Mtwo NiTi files in the management of calcified root canals. METHODS: Thirty-five calcified root canals from 21 cases unsuccessfully prepared with C-Pilot files and EDTA were treated with Mtwo NiTi files and EDTA. The data was analyzed with SAS 9.4 software package. RESULTS: Twenty-three calcified root canals were successfully prepared. The success rate was 65.71%. Instrument separation occurred in 4 root canals, and ledge occurred in 3 root canals. Categorized by calcified position, the success rate of three groups had no significant differences (P>0.05). CONCLUSION: Mtwo NiTi files can effectively process calcified root canals.

[Preparation and evaluation in vivo and in vitro of glimepiride gel-matrix controlled-release patch].

AIM: To study the pharmaceutical characterization, the pharmacokinetics and relative bioavailability of glimepiride gel-matrix controlled-release patch in rats. METHODS: An HPLC method was established for the determination of glimepiride in the permeation receptor and patch. The permeation rate and penetration mechanism of glimepiride-TDDS through rabbit skin in vitro was examined. The determination of drug content and the examination of weight difference and stability of the glimepiride-TDDS were carried out. Another HPLC method after pre-column derivatization was developed to determine the glimepiride serum concentration and then employed to study the pharmacokinetics and relative bioavailability of glimepiride after a single dose of oral or patch administration in rats. RESULTS: The permeation tests through excised rabbit skin demonstrated that the optimized glimepiride controlled-release patch exhibited zero-order kinetic characteristics that satisfied the demands of original design. The determination of glimepiride content and the quality control of weight difference of the patch accorded with Pharmacopoeia of the People's Republic of China of 2000 edition and the pharmaceutical characterization showed good stability. The HPLC method for the determination of serum glimepiride was shown to be a sensitive and simple one. The pharmacokinetic results showed that TDDS could decrease the maximum serum concentration, prolong the peak time, extend the MRT by 5.5 times compared with oral administration and maintain the serum concentration of glimepiride at a higher level even after 120 h of administration. The relative bioavailability of glimepiride-TDDS was 20.3% versus oral administration. CONCLUSION: The glimepiride-TDDS showed a slower, longer and smoother serum concentration-time profile, as compared with conventional oral administration in both absorption and elimination phase. As a result, it was evident that the patch exhibited good controlled-release properties.

Effects of deferoxamine on the repair ability of dental pulp cells in vitro.

INTRODUCTION: In previous studies, we found that hypoxia promoted the mineralization of dental pulp cells (DPCs). However, the clinical application of hypoxia as a therapy is questionable or unfeasible. Deferoxamine (DFO), a medication for iron overload, has also been shown to induce hypoxia. The purpose of this study was to investigate the effects of DFO on the repair ability of DPCs. METHODS: DPCs were obtained by using a tissue explant technique in vitro and were treated with different concentrations of DFO or hypoxia culture for 2 days. The viability, proliferation, migration, and odontogenic differentiation of DPCs were assayed and analyzed. The expression of hypoxia-inducible factor 1-alpha (HIF-1α) was assessed through Western blotting. RESULTS: Ten micromolars of DFO enhanced the expression of HIF-1α similarly to hypoxia and did not affect the viability of DPCs for 2 days. Furthermore, the proliferation, migration, and odontogenic differentiation of DPCs were promoted by DFO. CONCLUSIONS: These results suggest that DFO might improve the repair ability of DPCs by HIF-1α.

Effect of Porphyromonas gingivalis and Lactobacillus acidophilus on secretion of IL1B, IL6, and IL8 by gingival epithelial cells.

Porphyromonas gingivalis alters cytokine expression in gingival epithelial cells, stimulating inflammatory responses that may lead to periodontal disease. This study explored the effect of Lactobacillus acidophilus on the specific expressions of the interleukins (ILs) IL1B, IL6, and IL8 induced by the pathogen. Human gingival epithelial cells were co-cultured with P. gingivalis, L. acidophilus, or L. acidophilus + P. gingivalis; the control group consisted of the cells alone. Protein and gene expression levels of the ILs were detected using ELISA and qRT-PCR, respectively. The supernatant from the P. gingivalis group held significantly higher protein and mRNA levels of IL1B, IL6, and IL8, compared to the control group. In the mixed bacterial group (L. acidophilus + P. gingivalis), the levels of all three ILs decreased with increasing concentrations of L. acidophilus and were significantly different from the P. gingivalis group. This suggests that in gingival cells, L. acidophilus offsets the P. gingivalis-induced secretion of these ILs in a dose-dependent manner.

[Antagonistic effects of Lactobacillus acidophilus and Bifidobacterium adolescents on periodontalpathogens in vitro].

PURPOSE: To evaluate the possible antagonistic effects of Lactobacillus acidophilus (La) and Bifidobacterium adolescents (Ba) on Porphyromonas gingivalis (Pg) and Fusobacteriurn nuclearum (Fn). METHODS: Cylinder plate method was used to observe the inhibition zone formation.The suspensions of periodontal pathogens were mixed with cell free solutions of probiotics respectively, to investigate the antagonistic effect on the production of probiotics. The data were analyzed by ANOVA using SAS 9.0 software package. RESULTS: La only inhibited the growth of Pg. The cell free extract of La also significantly inhibited the growth of Pg (P<0.001). There was no antagonistic effect of Ba on the two periodontal pathogens. CONCLUSIONS: La strongly inhibits the growth of Pg by its metabolites. The new strategy of confining periodontal pathogens with La as ecological modulator is worthy of further study.

[The use of 1% dyclonine and local cryoanesthesia plus pulp vitality test agent in taking dental X-ray film].

PURPOSE: To analyze the effect of topical anesthetics in taking dental X-ray film. METHODS: 300 patients, who needed to take dental X-ray photography of maxillary or mandibular molar were randomly assigned to 3 groups. Bisecting angle technique was used to take the film. Before taking the X-ray, the throats of the patients in Group I were treated by 1% dyclonine spraying anesthesia, Group II were treated by FRILJET local cryoanesthesia and pulp vitality test agent, and Group III were set as control. The anesthesia efficiency and imagine quality of the dental films were evaluated, and the anesthetic time was recorded. The data was analyzed with ANOVA and Chi-square test using SPSS12.2 software package. RESULTS: The anesthesia efficiency was 99% in group I, 98% in Group II, and 62% in Group III. The imagine quality in Group I and II was higher than that in Group III. For both anesthesia efficiency and imagine quality, there was no significant difference between Group I and Group II, but there was significant difference between Group I and Group III, and between Group II and Group III (P<0.01).Significant difference of anesthetic time was showed between Group I and Group II . Compared with Group II, longer time(4 minutes) was needed in Group I to show the anesthetic effect, and it lasted longer for 21.62+/-3.54 minutes; while in Group II, the anesthetic effect lasted shorter, only for 2.07+/-1.22 minutes, but it developed immediately. CONCLUSION: The use of local anesthetics improves the accuracy, quality, and success rate in taking dental X-ray films.

[Analysis of pathogenic relations between dental caries and periodontitis].

OBJECTIVE: In order to search the cause of dental caries and periodontitis. METHODS: Selected 70 patients with severe chronic periodontitis (CP group) and 50 patients with caries sensitivity (CS group) in clinical adults of oral medicine (18 to 50-year-old) during 1 year. Parameters of oral hygiene, caries and periodontitis were recorded in the typical groups of CP and CS. RESULTS: The patients of CP group had rare caries, DFS in the groups of CP and CS was 1.46+/-2.60 and 17.32+/-7.55 respectively(p<0.001),while the patients of CS group had relative periodontal health indeed, CPTNI in CS and CP groups were 0.98+/-0.63 and 3.24+/-0.62 respectively (p<0.001), and the number of missing teeth was 1.90+/-3.34 and 1.10+/-1.85 respectively(p>0.05). 3 patients(only 2.4%)confirmed the parameters of caries sensitive as well as severe periodontitis. CONCLUSION: The correlating pathogenesis of caries and periodontitis seems to have antiagonism tendency. The ecological connection and bacterial interaction are worthy of further study.

[Juvenile periodontitis survey in 9548 middle school students at Huangpu District in Shanghai].

OBJECTIVE: 9548 middle school students from 11-19 age at Huangpu District in Shanghai were investigated to study the prevalence of juvenile periodontitis(JP). The purpose of the present study was to discover JP at early stage and make correct diagnosis, so the patients can be treated on time. METHODS: From January 2001 to April 2001, debris index(DI), calculus index(CI), sulcus bleeding index(SBI) and community periodontal index for treatment needs (CPITN) were examined in each student. RESULTS: In 9548 investigated (4739 males and 4809 females), prevalence of JP was 0.76%, the ratio of males to females was 1:1.03 (P<0.05). With aging, the detectable rate of gingival bleeding and calculus was increasing, the prevalence of JP was also increasing. CONCLUSION: Since the new classification system of periodontal disease was established, the above cases are worth reevaluating. We should also enhance oral hygiene of the young people.