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Ronak Mukundkumar Shah BDS Meena Ajay Aras MDS Vidya Chitre MDS 《Journal of prosthodontics》2015,24(4):339-342
Saliva is a valuable oral fluid that is often taken for granted. Impaired salivary function is a major and a debilitating sequela of radiation treatment for patients with head and neck cancer. It can persist for years and thereby increases the risk of oral infection significantly. Moreover, it has a notably negative impact on the quality of life of such patients. To help overcome this problem, a number of techniques have been proposed for incorporating a reservoir containing salivary substitute into a removable prosthesis. A new design for a functional salivary reservoir is presented here. This design is simple to construct and easily maintained by the wearer. Details of its design, construction, and other potential advantages are presented. 相似文献
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Aaron N. Seet BSc BDS DClinDent Peter S. Zilm BSc PhD Neville J. Gully BSc PhD Peter R. Cathro MDS Cert.Tert.T. 《Australian endodontic journal : the journal of the Australian Society of Endodontology Inc》2012,38(3):100-106
The effectiveness of sonic activation, laser activation and syringe irrigation of 4% sodium hypochlorite in removing an Enterococcus faecalis biofilm was compared. Biofilms were grown in extracted human single rooted teeth using a flow cell apparatus. After 4 weeks' growth, teeth were subjected to each treatment using 4% sodium hypochlorite and radicular dentinal surfaces of the root canals were analysed by scanning electron microscopy. Results showed that sonic activation and syringe irrigation with sodium hypochlorite showed reduced numbers of bacterial cells on the radicular dentine but were not effective in eliminating E. faecalis in the dentinal tubules. Laser activation of sodium hypochlorite resulted in clean dentine walls and undetectable levels of bacteria within dentinal tubules. Qualitatively, sonic or laser activation of 4% NaOCl resulted in greater bacterial reduction compared with syringe irrigation, with laser activation producing the greatest overall reduction. 相似文献
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Isabel F. Tresguerres DDS MD PhD Celia Clemente MD PhD Luis Blanco DDS MD PhD Ameen Khraisat BDS PhD Faleh Tamimi DDS PhD Jesús A.F. Tresguerres MD PhD 《Clinical implant dentistry and related research》2012,14(3):395-399
Purpose: The aim of this study was to assess the effect of local melatonin administration on bone osseointegration around implants in rabbit tibiae. Material and Methods: Ten female, 6‐month‐old New Zealand rabbits were randomly divided into two groups: the experimental group, where five rabbits were treated with local application of melatonin (3 mg) to implant sites when placed into the rabbit tibia, and the control group, those who where without additive materials. Four weeks later, animals were sacrificed; tibiae were dissected from soft tissues and fixed in buffered formaldehyde, and then included in methacrylate. Histological sections were performed to be studied under light microscopy and analyzed morphometrically to evaluate the amount of bone to implant contact (BIC), trabecular area density, and cortical area density. One‐way analysis of variance test was used for statistical evaluation. p < .05 was considered to be significant. Results: Histological evaluation showed more trabecular reaction in the melatonin group. Morphometrical analysis showed a statistically significant increase in trabecular BIC in the melatonin group when compared with the control group (24.61% ± 2.87 vs 13.62% ± 1.44; p < .01). Cortical BIC was decreased in the melatonin group, without statistical significance (71.08 ± 3.63 vs 76.28 ± 2.57; p = 0.31). Trabecular area density was increased significantly in the melatonin group (8.68 ± 1.61 vs 4.02 ± 0.36; p < .05). Cortical area density was decreased significantly in the melatonin group (91.31 ± 1.6 vs 95.7 ± 0.5; p < .05). Conclusion: Within the limitation of this animal study, local melatonin application at the time of implant placement might induce more trabecular bone at implant contact and higher trabecular area density. 相似文献
26.
Michael R. Fenlon MA PhD BDentSc FDS Andrew Lyons BDS FRCS Suzanne Farrell BDS PhD Kalpesh Bavisha BDS FDS Avijit Banerjee BDS PhD Richard M. Palmer BDS PhD 《Clinical implant dentistry and related research》2012,14(2):266-272
Background: Bone‐containing vascularized grafts have been used successfully to reconstruct post‐cancer surgical defects. Dental implants can be placed in these bone‐containing grafts to allow implant‐supported prosthodontic reconstruction of these patients. Purpose: The aim of this study was to evaluate the survival of dental implants used in the rehabilitation of subjects treated with bone‐containing vascularized grafts to compare usability of implants placed at the time of reconstruction and after healing. Materials and Methods: A cross‐sectional study was undertaken to examine survival rates of implants placed in vascularized bone‐containing grafts either immediately at the time of surgical reconstruction or after 3 months healing. Other factors such as graft type, whether radiation therapy was given, and implant type were recorded. Results: A total of 41 patients had 145 implants placed in 47 vascularized bone‐containing flaps. Increased failure rate of implants was seen in immediately placed implants. There was also a significant increase in the number of osseointegrated implants that were prosthodontically unusable or sub‐optimally placed in the immediate placement group. Radiation therapy was associated with a significant increase in failure rate. Modern implant surfaces appeared to perform better than machined/turned surfaces. Graft donor site did not influence implant survival. Conclusion: This study demonstrated the difficulties encountered with immediate placement of dental implants at the time of post‐cancer reconstructive surgery. 相似文献
27.
Anshul Mehra BDS MDS FAGE Keerthilatha M. Pai BDS MDS 《Clinical implant dentistry and related research》2012,14(1):100-111
Objectives: To evaluate the dimensional accuracy of panoramic cross‐sectional tomography, its impact on implant size estimation and its ability in identifying the inferior alveolar canal in the mandibular posterior region. Material and Methods: Eight partially edentulous mandibles with 18 edentulous sites were obtained. Orthopantomograms and tomograms were made and the mandible's outline and the position of mandibular canals on tomograms were traced on a clear acetate paper. Horizontal and vertical magnification factors were calculated. The mandibular height, distance between mandibular canal and alveolar crest, maximum bucco‐lingual width, distance between buccal cortex and mandibular canal, and cortical thickness at the inferior border of the mandible were measured. Potential implant sites were identified and implant sizes were estimated. Location and visibility of mandibular canals were also evaluated. The mandibles were sectioned at each site and all the above mentioned parameters were assessed which served as gold standard. Results: Mean horizontal and vertical magnification factors were 1.47 ± 0.048 and 1.53 ± 0.038. Total height and maximum bucco‐lingual width were underestimated by 1.88% and 1.59%. Crest to canal distance, cortical thickness at the inferior border of the mandible and buccal cortex to mandibular canal were overestimated by 0.59%, 5.16%, and 3.64%. Implant sizes were estimated for 11 sites and changes were recorded at 2 sites between record 1 and record 2. However, there was no disagreement between record 2 and record 3. Of the canals, 61.11% were located lingually and the visibility of mandibular canals was poor in 44.44% of cases. Conclusions: The tomograms were found to be accurate for the measurements in both horizontal and vertical planes and reliable for implant size estimation, taking into consideration proper magnification factors. They were also found to be useful in assessing the location of mandibular canal but were not very effective in discerning it. 相似文献
28.
N. Subha V. PrabhakarMinu Koshy BDS MDS K. AbinayaM. Prabu BDS MDS Lavanya Thangavelu BDS MDS 《Journal of endodontics》2013
Background
The aim of this investigation was to compare the effectiveness of 3% sodium hypochlorite (NaOCl), 2% chlorhexidine, 1% peracetic acid, and 10% povidone-iodine in the rapid disinfection of Resilon (Pentron Clinical Technologies, LLC, Wallingford, CT) and gutta-percha cones contaminated with Enterococcus faecalis and Bacillus subtilis.Methods
Two hundred fifty-six samples consisting of 128 gutta-percha cones and 128 Resilon cones were used in this study. The materials were tested for disinfection according to the type of solution (3% NaOCl, 2% chlorhexidine, 1% peracetic acid, or 10% povidone-iodine), the time of exposure to each solution (1 or 5 minutes), and the type of microorganisms (E. faecalis or B. subtilis). Subsequent to the disinfection, samples were placed in test tubes containing 10 mL Mueller-Hinton broth and incubated at 37°C for 7 days. All test tubes were observed at 24-hour intervals and visually checked for turbidity, signifying microbial growth.Results
In this study, 1% peracetic acid showed the best results for both 1 minute and 5 minutes of disinfection, 2% chlorhexidine showed the second best results although it was statistically at par with peracetic acid, and 3% hypochlorite ranked third in disinfection; this was statistically significant when compared with peracetic acid and chlorhexidine. Disinfection by povidone-iodine was the least within all the groups for both contact times although disinfection for 5 minutes showed better results than disinfection for 1 minute for gutta-percha.Conclusions
The outcome of this study confirmed the efficacy of 1% peracetic acid and 2% chlorhexidine in the rapid disinfection of both Resilon and gutta-percha. 相似文献29.
Dennis Ola BChD MSc DDPHRCS Ana B. O. Gambôa BDS MSc DDPHRCS PhD Morenike O. Folayan BChD FWACS MBA Wagner Marcenes BDS MSc PhD 《Journal of public health dentistry》2013,73(2):158-165
Objective: To test the relationship between socioeconomic position (SEP), family composition, number of siblings, and birth position in the family, and the utilization of oral health services by senior secondary school pupils in Ile‐Ife, Nigeria. Methods: A cross‐sectional study design included senior secondary school pupils in the Central Local Government Area of Ile‐Ife during 2007/2008. Sample size calculation was performed and 1,200 pupils were invited to participate. A multistage, stratified sampling technique was used. Data collection included a self‐administered questionnaire. Data were analyzed using logistic regression. Results: The response rate was 76 percent (n = 1043). The mean age was 15.8 (standard deviation = 1.9) and 49 percent were males. Only 22.5 percent of pupils had ever visited a dentist in their lives. Results from multivariate analyses showed that pupils attending free schools, those paying 1 to 10,000 naira (equivalent to US$ 63.31) and 10,000 to 19,000 naira (equivalent to US$ 120.29) were respectively 1.93, 1.87, and 2.74 times less likely to have attended a dentist in the past than pupils in more expensive schools. Pupils living with single mothers or without a parent were unlikely to have visited the dentist. Number of siblings and birth position in the family were not associated with utilization of oral health services. Conclusions: Adolescents from families with a low SEP growing up without their parents may need extra incentives to visit dentist. 相似文献
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