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71.
BACKGROUND. Early in life, vaginally delivered infants exhibit a different composition of the gut flora compared with infants delivered by caesarean section (C-section); however, it is unclear whether this also applies to the oral cavity. AIM. To investigate and compare the oral microbial profile between infants delivered vaginally and by C-section. DESIGN. This is a cross-sectional case-control study. Eighty-four infants delivered either vaginally (n = 42) or by C-section (n = 42) were randomly selected from the 2009 birth cohort at the County Hospital in Halmstad, Sweden. Medically compromised and premature children (<32 weeks) were excluded. The mean age was 8.25 months (range 6-10 months), and parents were asked to complete a questionnaire on socioeconomic factors, lifestyle, and hygiene habits. Saliva was collected and analysed using checkerboard DNA-DNA hybridization. RESULTS. A higher prevalence of salivary Streptococcus salivarius, Lactobacillus curvata, Lactobacillus salivarius, and Lactobacuillus casei was detected in infants delivered vaginally (P < 0.05). The caries-associated bacteria Streptococcus mutans and Streptococcus sobrinus were detected in 63% and 59% of all children, respectively. CONCLUSION. A significantly higher prevalence of certain strains of health-related streptococci and lactobacilli was found in vaginally delivered infants compared with infants delivered by C-section. The possible long-term effects on oral health need to be further investigated.  相似文献   
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Introduction

Regenerative endodontic procedures have emerged as a new treatment. The aim of this case report was to describe a regenerative autologous cellular therapy using mesenchymal stem cells from inflamed dental pulp and leukocyte platelet-rich fibrin (L-PRF) in a mature tooth.

Methods

A healthy 50-year-old man consulting for spontaneous dental pain was referred for endodontic treatment in tooth #28, which was diagnosed with symptomatic irreversible pulpitis. Inflamed dental pulp was extracted and transported to a good manufacturing practice laboratory for the isolation and culture of dental pulp stem cells (DPSCs). L-PRF was obtained from the patient's blood and was introduced into the instrumented and disinfected root canal, and expanded DPSCs were inoculated into the clot. The cervical part of the root canal was sealed with Biodentine (Septodont, Saint-Maur-des-Fosses, France) and a composite resin.

Results

Follow-up examinations were performed 6 months and 3 years later. The examinations included periapical radiographs (to measure the periapical index [PAI]), cone-beam computed tomographic (CBCT) imaging, sensitivity, and vitality tests. Clinical evaluations revealed normal responses to percussion and palpation tests. The tooth had a delayed response to cold, and the electric pulp test was responsive. The PAI and CBCT imaging revealed that the periapical area remained normal with a PAI score of 1 and a CBCT PAI score of 0. The vitality test performed indicated low blood perfusion units.

Conclusions

This case study reveals the potential use of a patient's own DPSCs and L-PRF as an alternative procedure for the treatment of pulpitis in mature permanent teeth. It also paves the way for the design of personalized cell-based clinical trials in regenerative endodontics.  相似文献   
79.
Objective: To determine the prevalence of dental prosthetic restorations in an adult population, to study the agreement between self-reports and clinical findings of prosthetic restorations, and to study answers from a questionnaire in relation to the prevalence of prosthetic restorations.

Material and methods: A questionnaire was sent to a sample of 10,000 adults. A further sample of 1000 individuals was invited to answer the questionnaire and also participate in a clinical study. The agreement between self-report and clinical findings was analyzed, as were the associations between prosthetic restorations and questionnaire responses, using the chi2 test.

Results: A total of 40% of the sample had fixed dental prostheses (FDP), 2.7% had removable dentures. The agreement between self-report and clinical findings was 93%. 34.7% of the individuals with no prosthetic restorations were university graduates and 4% of individuals with removable complete dentures. Oral health had the greatest impact on the quality of life of younger individuals with FDP, with an OHIP-14 (Oral Health Impact Profile) score of 7.3 for the age group 20–39 years compared to 4.9 for the age group 65–89 years. Conclusion: The questionnaire method can be a cost-effective way to determine the prevalence of prosthetic restorations.  相似文献   
80.
The aim of the present study was to evaluate the possible benefit of platelet-rich plasma (PRP) in sinus grafting as compared with recombinant human bone morphogenetic protein-7 (rhBMP-7). For this purpose, we performed a bilateral sinus augmentation with anorganic bovine bone and simultaneous insertion of a titanium screw implant in five miniature pigs. Six hundred microliters of PRP and 15%-vol. autologous bone, which was collected with a trap during preparation of the implant recipient site, were added to the right sinus and 420 microl rhBMP-7 to the left sinus. A polychrome sequential labeling was performed. The animals were sacrificed 6 weeks after surgery. Undecalcified ground sections were evaluated by microradiography, digitized histomorphometry and under fluorescent light. The mean bone-implant contact using rhBMP-7 was 45.8% and 5.7% under PRP (P=0.002). The mean height of newly mineralized bone in the augmented area using rhBMP-7 amounted to 8.3 mm as opposed to 3.6 mm under PRP (P=0.013). Using PRP, the mean area of the newly formed bone was enhanced (51.3%) as compared with rhBMP-7 (33.1%); however, this difference was not statistically significant (P=0.081). In conclusion, under the selected experimental conditions the use of rhBMP-7 led to superior outcomes with regard to the osseointegration of dental implants and the height of new bone as compared with the use of PRP.  相似文献   
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