Biomedical subjects

W Kalk

Publications and source records attributed to W Kalk.

112 records · Page 7Linked to original sources

PubMedDate not supplied

Denture satisfaction in a comparative study of implant-retained mandibular overdentures: a randomized clinical trial.

This study compared the experiences with surgical procedures and treatment effects of a mainly implant-supported overdenture retained by a transmandibular implant with those of an implant tissue-supported overdenture retained by two cylindrical endosseous implants. Treatment had been assigned according to a balanced allocation method to 95 patients, including a control group who received only conventional complete dentures. Since some of the patients refused the allocated treatment, the "intention to treat" analysis was applied. The results show that the experiences with surgical procedures were significantly more positive for the transmandibular implant group than the endosseous implant group. The differences with respect to satisfaction, complaints, and subjective chewing ability were not statistically significant. These results were unexpected because the overdentures retained by the transmandibular implants were, to a much larger extent, supported by the implant than were the overdentures retained by two endosseous implants.

Adult↗

PubMedDate not supplied

The relationship of some histologic parameters, radiographic evaluations, and Periotest measurements of oral implants: an experimental animal study.

The objective of this study was to analyze the efficacy and correlation between clinical and histologic parameters used to evaluate oral implants. After extraction of the premolars and a healing time of 4 months in 16 Dutch goats, four Brånemark implants were placed in the maxillary left and right premolar regions. After a healing time of 6 months, followed by another 4 months with the permucosal abutments, the goats were sacrificed and the jaws were block-resected. Before histologic preparation, long-cone radiographs were made and Periotest scores of the implants were recorded. Bone level measured histomorphometrically were found to be 0.85 mm more apically, compared to that measured radiologically (P = .001). Furthermore, statistically significant correlations (P > 0.2) were not found between the Periotest values of the calcium-phosphate-coated and uncoated implants for (1) the first thread in contact with bone, or (2) with the total number of threads in contact with bone. It was concluded that the radiologic data overscored the real marginal bone level around screw-shaped oral implants, and that the Periotest device is neither able to discriminate between the first thread nor between the total number of threads in contact with bone.

Animals↗

PubMedDate not supplied

Treatment of the atrophic edentulous maxilla with implant-supported overdentures: a review of the literature.

PURPOSE: This article reviews the literature on maxillary implant-supported overdentures. MATERIALS AND METHODS: Retrospective studies and clinical reports comprise the majority of publications, with few prospective studies. RESULTS: Maxillary implant-supported overdentures are associated with implant and prosthesis survival rates similar to those of fixed implant prostheses when patients are matched for bone quantity and quality. High failure rates are associated with extreme atrophy, poor bone quality, and the use of short implants, which represent situations in which overdentures are most commonly used. CONCLUSION: Further research is required to elucidate the most appropriate implant number and distribution as well as the most favorable prosthetic constructions.

Alveolar Bone Loss↗

PubMedDate not supplied

Adjustments and complications of mandibular overdentures retained by four implants. A comparison between superstructures with and without cantilever extensions.

PURPOSE: The aims of the study were to evaluate the postinsertion care needed by patients treated with four implants to retain mandibular overdentures and to compare two types of superstructures. MATERIALS AND METHODS: The study consisted of 54 patients who had been treated with conventional maxillary dentures and mandibular overdentures retained by four implants and a triple-bar superstructure with cantilever extensions (28 patients) or without cantilever extensions (26 patients). Differences between both groups with regard to age, gender, length, and diameter of the implants and preoperative mandibular bone height were tested by means of Student's t and chi-square tests with a probability level of 0.05. No significant differences were found. Both groups were retrospectively compared on adjustments and complications. The follow-up period after insertion of the dentures was 2 years. RESULTS: During the 2-year follow-up, 17 patients of the cantilever-extension group and 20 patients of the group without cantilever extensions needed adjustments, and 17 patients of the cantilever group and 12 patients of the group without cantilever extensions had to be treated because of complications. Significantly more (P < 0.05, chi-square test) superstructure fractures were present in the cantilever group (14 occasions in 7 patients) than in the group without cantilever extensions (1 occasion). All superstructure fractures in the cantilever group involved the cantilever extensions. CONCLUSION: This study demonstrated a considerable need for postinsertion care, confirming the necessity of routine follow-up services for patients restored with implant-retained overdentures. Furthermore, the results of this study suggest restriction of the use of cantilever extensions.

Chi-Square Distribution↗