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Residual Ridge (residual + ridge)

Distribution by Scientific Domains

Medical Sciences	100%

Selected Abstracts

Responses of jawbone to pressure,

GERODONTOLOGY, Issue 2 2004
Gunnar E. Carlsson
Objective:, To provide a literature review of bone resorption of edentulous jaws focusing on responses to pressure. Background:, After the extraction of all teeth in a jaw there is a continuous reduction of the residual ridge. The individual variation of bone resorption is great, and the aetiology is complex and not yet well understood. Materials and methods:, A search of the literature published up to May 2003 on bone resorption and pressure was performed using PubMed/Medline. Results:, Animal studies have demonstrated that excessive and constant pressure induces bone resorption. Recent experimental research has indicated that bone resorption is a pressure-regulated phenomenon with a lower threshold for continuous than for intermittent pressure. Clinical studies have suggested that residual ridge resorption is due more to the effects of denture wearing than to disuse atrophy. However, the results of leaving out dentures at night are not conclusive. Nor does the literature offer any strong evidence for the so-called combination syndrome, which has been described as a result of unfavourable loading. Clinical studies using multivariate analyses indicate that female gender and systemic factors may be of greater importance than oral and denture factors. Implant-supported prostheses have a bone preserving effect rather than the continuing resorption under complete dentures. Conclusions:, The best way to reduce bone resorption is to avoid total extraction, preserve a few teeth and fabricate overdentures. In edentulous jaws, placement of implant-supported prostheses will lead to less bone loss and may even promote bone growth. To increase our knowledge of residual ridge resorption extended experimental, clinical and statistical methods will be needed, preferably including collaboration between dental and medical researchers. [source]

Impact of Human Genome Project on treatment of frail and edentulous patients,

GERODONTOLOGY, Issue 1 2004
Ichiro Nishimura
Objective:, Because of ongoing increases in life expectancy and deferment of edentulousness to older age, dentists are facing a different challenge to satisfy elderly denture wearers with a higher prevalence of chronic diseases. This discussion introduces the Human Genome databases as novel and powerful resources to re-examine the core problems experienced by frail and edentulous patients. Background:, Recent studies demonstrated that mandibular implant overdentures do not necessarily increase masticatory function, perception and satisfaction in denture wearers with adequate edentulous residual ridges. It has been demonstrated that the rate of edentulous residual ridge resorption significantly varies among individuals. The prognosis and cost-effectiveness of denture treatment, with or without implants, may largely depend on how the edentulous ridge is maintained. However, reliable clinical methods permitting dentists to predict the long-term health of the edentulous residual ridge are lacking. Materials and methods:, With the completion of the Human Genome Project, the genomic sequence database from this multinational consortium will provide a unique resource to determine the genetic basis of similarity and diversity of humans. Results:, One base pair in every 100 to 300 base pairs of the genome sequence varies among humans, suggesting that genetic diagnosis using the single nucleotide polymorphisms (SNPs) may provide a novel opportunity to differentiate our edentulous patients. Conclusions:, Future dental service for the elderly will require a personalized care paradigm, using highly sensitive diagnostic technology such as SNP genomic analysis, for recommending the treatment with greatest potential benefit. [source]

Finite element analysis of the effect of the bucco-lingual position of artificial posterior teeth under occlusal force on the denture supporting bone of the edentulous patient

JOURNAL OF ORAL REHABILITATION, Issue 6 2003
G. Nishigawa
summary, To improve the quality of the complete denture prosthesis, the bucco-lingual position of the artificial posterior teeth must be determined with consideration of the shape of the maxillary and mandibular residual ridge and the relationship between them. The arrangement of posterior artificial teeth should be considered not only for the denture stability but also for the avoidance of high pressure on the supporting structures. A two-dimensional finite element method program to investigate the statics for the contour of the complete denture and the residual ridge was developed. With this program, the effect of the bucco-lingual position of the artificial posterior teeth under occlusal force on the denture supporting bone could be investigated. [source]

Effect of viscoelastic properties of resilient denture liners on pressures under dentures

JOURNAL OF ORAL REHABILITATION, Issue 11 2001
N. Taguchi
In order to evaluate the influence of viscoelastic properties of resilient denture liners on the pressures under dentures, a series of creep and stress relaxation tests were carried out using a simplified mandibular edentulous model and denture model. Two diaphragm pressure sensors were attached to the edentulous model so that they contacted the residual ridge and the buccal slope. The results may be summarized as follows: (i) The use of resilient denture liners is effective for stress relief under dentures. (ii) The thickness increase of each denture liners causes the effect of stress relaxation. (iii) The material exhibited viscoelastic behaviour after applying the stress and has the ability to distribute stress or stress relaxation. It is important to understand the viscoelastic behaviours of each resilient denture liner and choose the material according to the clinical situation. The information obtained should be useful to clinicians when they select materials for their patients. [source]

Ramus or Chin Grafts for Maxillary Sinus Inlay and Local Onlay Augmentation: Comparison of Donor Site Morbidity and Complications

CLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 3 2003
Jaime Clavero DDS
ABSTRACT Background: The placement of endosseous implants in edentulous areas is frequently limited by inadequate bone volume of the residual ridge. Local bone grafts from the mandible are a convenient source of autogenous bone for alveolar reconstruction prior to implant placement. Purpose: The aim of the present study was to document and compare the morbidity and the frequency of complications occurring at two intraoral donor sites: the mandibular symphysis and the mandibular ramus. Material and Methods: This study reviewed 53 consecutively treated patients:29 with autogenous bone grafts from the mandibular symphysis and 24 with mandibular ramus bone grafts. Each patient received a questionnaire 18 months after surgery regarding problems that may have occurred during the postoperative period. Results: In the patients in whom bone was harvested from the mandibular ramus, there were fewer postoperative symptoms immediately after the operation than with mandibular symphysis harvesting. Twenty-two of the 29 patients with symphysis grafts experienced decreased sensitivity in the skin innervated by the mental nerve 1 month after the operation. Five of the 24 patients with ramus grafts experienced decreased sensitivity in the vestibular mucosa corresponding to the innervation of the buccal nerve. Eighteen months after the surgery, 15 of the 29 patients in the symphysis group still had some decreased sensitivity and presented with permanent altered sensation. Only one of the patients grafted from the mandibular ramus presented with permanent altered sensation in the posterior vestibular area. No major complication occurred in the donor sites in any of the 53 patients. Conclusion: The results of this study favored the use of the ascending mandibular ramus as an intraoral donor site for bone grafting. [source]

Alveolar ridge preservation with guided bone regeneration and a synthetic bone substitute or a bovine-derived xenograft: a randomized, controlled clinical trial

CLINICAL ORAL IMPLANTS RESEARCH, Issue 7 2010
Nikos Mardas
Abstract Objectives: The aim of this randomized, controlled clinical trial was to compare the potential of a synthetic bone substitute or a bovine-derived xenograft combined with a collagen membrane to preserve the alveolar ridge dimensions following tooth extraction. Methods: Twenty-seven patients were randomized into two treatment groups following single tooth extraction in the incisor, canine and premolar area. In the test group, the alveolar socket was grafted with Straumann Bone Ceramic® (SBC), while in the control group, Bio-Oss® deproteinized bovine bone mineral (DBBM) was applied. In both groups, a collagen barrier was used to cover the grafting material. Complete soft tissue coverage of the barriers was not achieved. After 8 months, during re-entry procedures and before implant placement, the horizontal and vertical dimensions of the residual ridge were re-evaluated and trephine biopsies were performed for histological analysis in all patients. Results: Twenty-six patients completed the study. The bucco-lingual dimension of the alveolar ridge decreased by 1.1±1 mm in the SBC group and by 2.1±1 in the DBBM group (P<0.05). Both materials preserved the mesio-distal bone height of the ridge. No differences in the width of buccal and palatal bone plate were observed between the two groups. The histological analysis showed new bone formation in the apical part of the biopsies, which, in some instances, was in direct contact with both SBC and DBBM particles. The coronal part of the biopsies was occupied by a dense fibrous connective tissue surrounding the SBC and DBBM particles. Conclusion: Both biomaterials partially preserved the width and the interproximal bone height of the alveolar ridge. To cite this article: Mardas N, Chadha V, Donos N. Alveolar ridge preservation with guided bone regeneration and a synthetic bone substitute or a bovine-derived xenograft: a randomized, controlled clinical trial. Clin. Oral Impl. Res. 21, 2010; 688,698. [source]