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51.
OBJECTIVE: To compare early dental implant loading in irradiated and non-irradiated oral cancer patients in order to accelerate masticatory function improvement and quality of life. PATIENTS AND METHODS: One hundred and fourteen non-submerged interforaminal ITI implants were early loaded in 30 patients after 3 weeks in situ (telescoped overdenture). Nineteen patients received 72 implants (63%) after local irradiation; 11 non-irradiated patients received 42 implants (37%) with a 24-month follow-up. RESULTS: At 24 month follow-up, one early failure had occurred in an irradiated patient (=99% functioning implants in situ). Peri-implant bleeding and plaque index were similarly high in both groups (40 to 68% average).The Results of other measured parameters were as follows (values for mean; irradiated; non-irradiated patients with respective standard deviations; significance of comparison): bone loss (0.9+/-0.9; 1.4+/-0.9; 0.4+/-0.5 mM; P<0.01); Periotest score (-2.7+/-2.7; -2.4+/-2.2; -3.1+/-3.3; P<0.2); gingival recession (0.6+/-0.7 mM; 0.8+/-0.9 mM; 0.4+/-0.5 mM, P<0.02); and peri-implant probing depths (3+/-1.2; 2.6+/-0.6; 3.4+/-1.7 mM; P<0.002). CONCLUSION: The results suggest reliable non-submerged implantation and early loading. However, bone loss in irradiated mandibles, combined with higher average Periotest values and gingival recession in an oral environment of altered saliva quantity, quality, microflora and local scarring, requires extended follow-up.  相似文献   
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The salivary and thyroid glands. A comparative study in man   总被引:2,自引:0,他引:2  
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53.
The purpose of this study was to evaluate crestal bone loss around 282 two-piece implants with straight (n = 193) and platform-switched (n = 89) abutment connections after placement at various crestal levels. Implants were assigned into two groups according to straight and platform-switched abutment connections. Each group was further subdivided into three groups depending on the location (supracrestal, crestal, or subcrestal) of the implant cervical platform. Linear measurements of bone resorption were made from the implant's platform to the first point of bone-to-implant contact at the time of implant placement and 2 years postrestoration. Data were statistically analyzed. Statistically significant differences were found between subgroups in both straight and platform-switched categories. The only nonstatistically significant difference (P = .341) arose when comparing the supra- and subcrestal locations in the straight abutment connection group. The platform-switched group exhibited significantly less bone loss (P = .046) only in subcrestal locations. The platform-switched concept was not beneficial during the overall comparison, but it was for the subcrestal location of the abutment connection. Crestal placement of the implant-abutment connection resulted in higher marginal bone resorption in both straight and platform-switched abutments.  相似文献   
54.
Abstract Aim: This study examined how well patients accepted and to what extent they were impaired by Invisalign® treatment. Patients and Methods: Fifty-four consecutive patients received a questionnaire with 12 questions after 3 to 6 months of Invisalign® treatment. They were given a choice of three responses for each question. Apart from personal data, the questionnaire covered the following parameters: adaptation time, occurrence and duration of pain, possible speech impairment, lingual and mucosal irritations, temporomandibular joint (TMJ) problems and subjective assessment of the success of therapy thus far and the quality of information initially provided. Results: 78% of those interviewed were females. The highest percentage of patients (44%) were between 20 and 30 years of age. 83% got used to their aligners within one week. 35% had no pain and 54% mild pain while wearing them. This pain usually lasted for 2 to 3 days following insertion of a new aligner. 46% of the patients experienced no speech impairment. 93% felt so secure with their aligners that they felt not at all inhibited about speaking. The majority noticed no narrowing of the lingual space (76%) or irritation of the lingual or buccal mucosa (70%). However, 6% had strong irritations. 44% of the patients had difficulty chewing, mainly because the teeth were sensitive to pressure or had food particles caught between them due to temporary gaps. TMJ problems in terms of clicking were reported by 8% of the patients, although the clicking had existed before therapy initiation. None of the patients had TMJ pain. At the time of the interview, 89% of the patients were satisfied with the progress of therapy. All patients considered themselves well or very well informed about the treatment. Conclusions: Invisalign® therapy seems particularly attractive to a clientele comparable to that for the lingual technique. Patients show high acceptance, since they become accustomed to the aligners very quickly and do not suffer much impairment. If indicated, Invisalign® therapy should thus be considered an alternative to the lingual technique for esthetically-demanding patients. This applies especially to patients who cannot be treated by the lingual technique because of the inevitable speech impairment.  相似文献   
55.
OBJECTIVES: To determine the longevity of heat-pressed glass ceramic inlays and onlays luted with solely light-curing composite resin. METHODS: The records of patients who had received a ceramic inlay or onlay at the Heidelberg University Department of Conservative Dentistry from 1993 to 2002 were evaluated. The mean observation time and the survival probability of the ceramic inlays and onlays was calculated with the aid of the Kaplan-Meier algorithm. This was done for the total number of all restorations as well as for various subgroups (number of surfaces, tooth type, endodontic condition at the time that the ceramic restoration was incorporated, experience of operator). The log-rank test was used to compare groups and look for significant differences, and p<0.05 was set to be statistically significant. In addition, 95% confidence intervals of the survival probability values were computed. RESULTS: At the time of the last observation, 783 (96.7%) of these restorations were still in place. The mean observation period for all ceramic restorations was 17.3 months (SD 20.2), with an observation interval of between 0 and 116 months. The last loss of a ceramic restoration was observed 45 months after it had been placed, so that the survival probability of all ceramic restorations amounted to p=0.90 (95% confidence interval 0.86-0.94) from this time onward. Factors such as endodontic condition of tooth, type of tooth, position of tooth, extent of restoration, experience of operator or gender of patient had no significant influence on the survival probability of the ceramic restorations. CONCLUSIONS: Heat-pressed glass ceramic inlays and onlays can be used successfully in routine clinical therapy. In addition, this type of inlays and onlays can be placed successfully with solely light-curing composite resin.  相似文献   
56.
Abstract Properly prepared straight root canals of freshly extracted maxillary canines and central incisors were used to evaluate the sealing ability of the sectional thermoplasticized gutta-percha obturation technique, with or without sealer and the single-phase thermoplasticized gutta-percha filling technique. The teeth were divided into 3 groups (A, B, C) of 20 teeth and were obturated using the 3 thermoplasticized gutta-percha techniques. Group A: single phase with sealer; group B: sectional technique without sealer; and group C: sectional technique with sealer. The obturated teeth were immersed in India ink for 3 days followed by clearing procedures. The teeth were then examined under a stereo microscope and the linear leakage was recorded. Statistical unpaired Student's t-tests showed significantly less dye penetration in teeth obturated using the sectional technique with sealer (group C) than in teeth obturated with the single-phase technique with sealer (group A) or the sectional technique without sealer (group B).  相似文献   
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ObjectiveThis research brief contains results from a national survey about telehealth use reported in a random sample of U.S. nursing homes.Methods and MaterialsThe sample includes nursing homes (N = 664) that completed surveys about information technology maturity, including telehealth use, beginning January 1, 2019, and ending August 4, 2020. A pre/post design was employed to examine differences in nursing home telehealth use for nursing homes completing surveys prior to and after telehealth expansion, on March 6, 2020. We calculated a cumulative telehealth score using survey data from 6 questions about extent of nursing home telehealth use (score range 0-42). We calculated proportions of nursing homes using telehealth and used logistic regression to look for differences in nursing homes based on organizational characteristics and odds ratios.ResultsSignificant relationships were found between nursing home characteristics and telehealth use, and specifically, larger metropolitan homes reported greater telehealth use. Ownership had little effect on telehealth use. Nursing homes postexpansion used telehealth applications for resident evaluation 11.24 times more (P < .01) than did nursing homes pre-expansion.DiscussionAdministrators completing our survey reported a wide range of telehealth use, including approximately 16% having no telehealth use and 5% having the maximum amount of telehealth use. Mean telehealth use scores reported by the majority of these nursing homes is on the lower end of the range.ConclusionsOne solution for the current pandemic is to encourage the proliferation of telehealth with continued relaxed regulations, which can reduce isolation and preserve limited resources (eg, personal protective equipment) while maintaining proper distancing parameters.  相似文献   
60.
Die Ophthalmologie - Eine Raumforderung der Lider im jungen Erwachsenenalter ist oft ein Zeichen einer Entzündung, eines Traumas oder einer benignen Neoplasie. Ziel dieser Kasuistik ist es,...  相似文献   
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