摘要:

The aim of the study was to compare the outcome of bridges supported by implants with bridges supported by a combination of implants and natural teeth abutments. The study comprised 23 patients with Applegate Kennedy Class I dentition in the mandible and a full upper denture. Implants ad modum Brånemark were inserted in the posterior areas of both mandibular quadrants. On one side, a bridge supported by 2 implants was constructed (Type I) and on the other side, a bridge supported by 1 tooth (mostly the canine or first premolar) and 1 implant was made (Type II). A total of 46 bridges were made and during the 3‐year follow‐up period, 4 Type I and 2 Type II bridges were lost. 8 out of 69 implants were lost during the 3‐year follow‐up, resulting in an implant survival rate of 88.4%. Marginal bone loss, one of several parameters, was evaluated on standardized intraoral radiographs. This was performed during the 1st and 2nd year of function and the total mean bone loss from loading was 0.46 mm and 0.56 mm, respectively. The bone loss during the 2nd year of function was significantly less, adjacent to implants supporting Type II bridges, than adjacent to implants supporting Type I bridges. Summarily, no disadvantages of combining of teeth and implants in the same bridge were found in this study. On the contrary, the slightly lower marginal bone loss adjacent to implants in Type II bridges may indicate that the bone reactions could be more favorable when bridges 1 are connected to both implants a

ISSN:0905-7161    

DOI:10.1034/j.1600-0501.1992.030201.x

出版商:Munksgaard International Publishers    

年代:1992

数据来源: WILEY

摘要:

Speech may be affected by the transition from complete dentures to fixed prosthesis on osseointegrated implants (OIB). If so, is there any correlation between interdental spaces (open or closed) in the prosthodontic construction and deteriorated speech? 21 individuals advocated for maxillary OIB were randomised so that one half of the group got constructions with wide interdental spaces and the other half with minimised inter‐dental spaces. All patients were examined audiologically and their speech was individually tape‐recorded before and after treatment. Perceptual, acoustic, model and audiological analyses were made. Approximately 60% of the patients were judged to have indistinct speech after the treatment. The s‐sound was perceptually and acoustically distorted. 67% of the patients suffered from hearing defects. No correlation between interdental spaces (open or closed) and deteriorated speech could be found. It is supposed, that hearing plays a part in the effort to adjust speech to a new maxillary OIB, and thus reduced hearing can enhance speech difficu

ISSN:0905-7161    

DOI:10.1034/j.1600-0501.1992.030202.x

出版商:Munksgaard International Publishers    

年代:1992

数据来源: WILEY

摘要:

For several years, osseointegrated implant‐supported overdentures have been used in the rehabilitation of full edentulism with excellent results, at least in the lower jaw. This study involved 3 groups of patients with different prosthetic reconstructions:(1) mandibular overdentures supported by 2 implants connected by a bar (30 patients), (2) mandibular fixed prostheses supported by 4–6 implants (25 patients) and (3) mandibular complete dentures without implant support as controls (85 patients). The primary aim of this study was to examine on orthopantomograms (by means of the area index to minimize distortion and magnification errors), posterior mandibular ridge resorption in the 3 treatment groups. The present data demonstrated a minimal posterior mandibular ridge resorption in patients with fixed implant‐supported prostheses. A more considerableposterior ridge resorption was observed in the complete denture group and especially in the overdenture wearers. For the latter, the annual posterior jaw bone resorption after the post‐extraction remodeling period of 6 months, was 2‐ to 3‐fold that of full denture wearers. When patients were edentulous for more than 10 years, the difference between the 2 latter groups disappeared. It is suggested that although the overdenture design on 2 implants offers advantages from a financial and failure rate point of view, its indications in younger patients should cautiously be evaluated in a long‐term perspective concerning posterior mandibular bo

ISSN:0905-7161    

DOI:10.1034/j.1600-0501.1992.030203.x

出版商:Munksgaard International Publishers    

年代:1992

数据来源: WILEY

摘要:

Hydroxyapatite‐coated and uncoated titanium screws were inserted in the rabbit tibial metaphysis and evaluated by histomorphometry after 6 months of follow‐up. There was no difference in direct bone contact between the HA‐coated implants and the uncoated controls. The effect of HA‐coating on screw‐shaped implants seems to be uncertain, in contrast to unthreaded cylindrical designs, where there is more abundant documentation in favour of HA‐coat

ISSN:0905-7161    

DOI:10.1034/j.1600-0501.1992.030204.x

出版商:Munksgaard International Publishers    

年代:1992

数据来源: WILEY

摘要:

The aim of the present study was to compare the anchorage of TiO2‐blasted screw and cylindrical implants with conventionally used machine‐produced screw and cylindrical implants inserted immediately in extraction sockets on dogs. 6 adult mongrel dogs had 3rd and 4th mandibular premolars extracted bilaterally and 24 commercial pure titanium implants were placed immediately in extraction sockets and covered with mucoperiosteum. Each dog had inserted 4 implants: 1 screw implant and 1 cylindrical implant blasted with titanium‐dioxide‐particles; 1 screw implant and 1 cylindrical implant with machine‐produced (m.p.) surface (controls). After a healing period of 12 weeks, 16 implants from 4 animals were used for removal torque test, which demonstrated that significantly higher removal torque force was needed to unscrew the implants blasted with titanium‐dioxide‐particles, than the normal m.p. implants. The medians for the TiO2‐blasted screw and cylindrical implants were>150 Ncm and 10.5 Ncm, respectively, while the values for the m.p. implants were 60 Ncm and 35 Ncm, respectively. The SEM investigation demonstrated a high irregularity of the TiO2‐blasted surface compared to the machined surface. The R, and R, values for surface roughness were higher for the TiO2‐blasted implants than for the normal m.p. implants. Histomorphometrically, the arithmetic mean of the direct bone‐implant contact fraction was 69%. There was no significant difference in direct bone‐implant contact length fraction between TiO2‐blasted implants and the control implants. The implants blasted with titanium‐dioxide‐particles in this study showed a better anchorage than implants with a machine‐produced surface. The screw implants showed a better anchorag

ISSN:0905-7161    

DOI:10.1034/j.1600-0501.1992.030205.x

出版商:Munksgaard International Publishers    

年代:1992

数据来源: WILEY

摘要:

The installment of endosseous dental implants has become an accepted treatment procedure, and the long‐term clinical results appear excellent. The composition of the soft tissue environment, however, is different from that around natural teeth. One characteristic of original junctional epithelium is its association with plasminogen activator (PA) activity. In 11 patients with a total of 30 IT1 hollow‐screw titanium dental implants, 16 biopsies were taken. Histologic cryostat sections were assayed for the presence of PA in the junctional epithelium. The results demonstrated that junctional epithelium around titanium implants yields PA activity in a manner very similar to that of natural teeth. The ability to produce this enzyme activity is not related to the developmental origin of the junctional cells, but to their position and function at the base of the gingival sul

ISSN:0905-7161    

DOI:10.1034/j.1600-0501.1992.030206.x

出版商:Munksgaard International Publishers    

年代:1992

数据来源: WILEY

摘要:

6 mandibles were radiographically examined bilaterally to visualise the mandibular canal. 5 imaging techniques were used: periapical radiography, panoramic radiography, hypocycloidal tomography, spiral tomography and computed tomography (CT). Panoramic radiographs were obtained with 2 different X‐ray machines. The CT‐examinations comprised direct images and standard reconstructions based on axial slices. The specimens were subsequently sectioned for contact radiography. The visibility of the mandibular canal was estimated by 3 observers at special reference points on all radiographs and classified as clearly visible, questionable visibility or not visible. The contact radiographs served as the “gold standard”. The inter‐observer and the intra‐observer agreement were assessed by calculating the overall agreement and the x. value. Direct coronal computed tomography, as well as spiral and hypocycloidal tomography, gave better visualisation of the mandibular canal than periapical and panoramic

ISSN:0905-7161    

DOI:10.1034/j.1600-0501.1992.030207.x

出版商:Munksgaard International Publishers    

年代:1992

数据来源: WILEY