Differences in the axonal compositions of the human mandibular nerve between dentulous and edentulous jaws. (9/97)

We examined the human mandibular nerve to find differences in the composition of nerve fiber axons between dentulous and edentulous jaws Using Goto's modification of Masson-Goldner's method. We discovered that the edentulous jaw did not contain any large size axons, compared with the dentulous jaw. This can be considered as evidence that the larger fibers innervating the periodontal ligament decreased degenerated after tooth loss.  (+info)

Implants in the medically compromised patient. (10/97)

Dental clinicians are confronted with an increasing number of medically compromised patients who require implant surgery for their oral rehabilitation. However, there are few guidelines on dental implant therapy in this patient category, so that numerous issues regarding pre- and post-operative management remain unclear to the dental clinician. Therefore, the aim of the present review is to offer a critical evaluation of the literature and to provide the clinician with scientifically based data for implant therapy in the medically compromised patient. This review presents the current knowledge regarding the influence of the most common systemic and local diseases on the outcome of dental implant therapy, e.g., abnormalities in bone metabolism, diabetes mellitus, xerostomia, and ectodermal dysplasias. Specific pathophysiologic aspects of the above-mentioned diseases as well as their potential implications for implant success are critically appraised. In line with these implications, guidelines for pre- and post-operative management that may assist in the successful implant-supported rehabilitation of this patient category are proposed.  (+info)

Clinical evaluation of osseointegrated implants in Tokyo Dental College Hospital (third report): long-term observation of functioning survival rate of fixtures. (11/97)

The objective of this report was to review 365 cases of Branemark Implant Bridge including 1,444 fixtures in patients of Tokyo Dental College Chiba Hospital. The term of implantation was divided into several phases; less than 1 year, from 1 year to 3 years, from 3 years to 5 years, from 5 years to 7 years, from 7 years to 10 years, more than 10 years, and the survival rate was calculated for each phase. The removal rate of fixture after connecting the superstructure was 13% in maxillary cases and 2% in mandibular cases. The functioning survival rate in maxillary cases slightly decreased from 91% in less than 1 year to 87% after more than 10 years; however, the functioning survival rate in mandibular cases was about 99% in all periods. The removal rate of fixtures per patient was 23% in maxillary cases and 6% in mandibular ones. The average removal number of fixtures was 1.8 in maxillary cases and 1.2 in mandibular ones. The removal of the fixture occurred most frequently at less than 1 year in maxillary cases, but there was no tendency for a pattern of removal of fixture in mandibular cases.  (+info)

Implant imaging for the dentist. (12/97)

Dental implants have become part of routine treatment plans in many dental offices because of their increasing popularity and acceptance by patients. Appropriate preplacement planning, in which imaging plays a pivotal role, helps to ensure a satisfactory outcome. The development of precise presurgical imaging techniques and surgical templates allows the dentist to place these implants with relative ease and predictability. This article gives an overview of current practices in implant imaging for the practising dentist, with emphasis on selection criteria. Imaging protocols for site assessment and restorative evaluation are discussed. This information will enable the dentist to select and use appropriate radiographic images (digital or film) for implant treatment planning, restoration and postoperative follow-up. Modalities presented include intraoral and panoramic projections, linear and complex motion tomography and computed tomography (CT). The use of CT image reformatting software such as Dentascan and SimPlant with 3-dimensional reconstructions is discussed.  (+info)

Implantology and the severely resorbed edentulous mandible. (13/97)

Patients with a severely resorbed edentulous mandible often suffer from problems with the lower denture. These problems include: insufficient retention of the lower denture, intolerance to loading by the mucosa, pain, difficulties with eating and speech, loss of soft-tissue support, and altered facial appearance. These problems are a challenge for the prosthodontist and surgeon. Dental implants have been shown to provide a reliable basis for fixed and removable prostheses. This has resulted in a drastic change in the treatment concepts for management of the severely resorbed edentulous mandible. Reconstructive, pre-prosthetic surgery has changed from surgery aimed to provide a sufficient osseous and mucosal support for a conventional denture into surgery aimed to provide a sufficient bone volume enabling implants to be placed at the most optimal positions from a prosthetic point of view. The aim of this paper is to review critically the literature on procedures related to the severely resorbed edentulous mandible and dental implant treatment. The study includes the transmandibular implant, (short) endosseous implants, and reconstructive procedures such as distraction osteogenesis, augmentation of the mandibular ridge with autogenous bone, and bone substitutes followed by the placement of implants. The number of patients participating in a study, the follow-up period, the design of the study, the degree of mandibular resorption, and the survival rate of the dental implants all are considered evaluation parameters. Although numerous studies have described the outcome results of dental implants in the edentulous mandible, there have been few prospective studies designed as randomized clinical trials that compare different treatment modalities to restore the severely resorbed mandible. Therefore, it is not yet possible to select an evidence-based treatment modality. Future research has to be focused on long-term, detailed follow-up clinical trials before scientifically based decisions in treating these patients can be made. This will contribute to a higher level of care in this field.  (+info)

Investigation of preferred viscosity of irreversible hydrocolloid on preliminary impression for edentulism. (14/97)

This study aims to investigate the preferred viscosity of irreversible hydrocolloid used in the preliminary impression for edentulism. Thirteen modalities of irreversible hydrocolloid were prepared by changing the W/P ratio. Discrimination test for the preferred viscosity was performed on 11 prosthodontists (10.4+/-5.3 years of prosthetic experience). The parameter of discrimination test (P%) was calculated as the ratio of the number of adequate tests to the total number of tests. The P% and apparent viscosity coefficient (eta a) values measured by rheometer demonstrated good correlation (Y = -35.8X2 + 118.4X - 22.8, r=0.86, p<0.01). Prosthodontists could judge the preferred viscosity based on their clinical experiences. On the preliminary impression for edentulism, the preferred viscosity demonstrated in vitro using a polyurethane maxilla model was 1.21 x 10(3) Pa x s.  (+info)

Implants in anatomical buttresses of the upper jaw. (15/97)

The skull presents a series of dense bony buttresses that conform a protective frame around the different craniofacial cavities. The middle third portion presents two anterior buttresses (frontomaxillary and frontozygomatic) and a posterior buttress (pterygomaxillary). In certain situations these structural supports allow the rehabilitation of free upper extremities in atrophic jaws by positioning parasinusal angulated implants--thereby avoiding the need for more complex reconstruction techniques such as sinus lifting or autografting procedures. The present study presents a review of the literature on implant insertion in anatomical buttresses of the upper jaw.  (+info)

Case report: restoration of edentulous mandible with 4 BOI implants in an immediate load procedure. (16/97)

Dental implants for insertion from the lateral aspects of the jaw bone have been described repeatedly, since 1972. Long term results have been reported. Due to their design, BOI-Implants (basal osseointegration) can be installed even in those cases, where the vertical bone supply is reduced. This applies to the distal areas of the maxilla and the mandible. Furthermore, BOI-implants allow immediate loading as long as a balanced masticatory function can be achieved and maintained. This paper reports on the steps taken to install a full lower bridge in 4 BOI-implants and restoration in a patient with a circular bridge. The bridge was made from CoCr-Alloy and covered with acrylic resin. This treatment technique reduces costs and treatment time by about 50% compared to conventional techniques.  (+info)