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E B Kenney

Publications and source records attributed to E B Kenney.

62 records · Page 4Linked to original sources

Isolation of anaerobic bacteria from human gingiva and mouse cecum by means of a simplified glove box procedure.

An anaerobic glove box constructed of clear flexible vinyl plastic is described. It is sufficiently inexpensive and simple in operation to be used not only in research but also in a clinical laboratory by technicians without special training. Conventional bacteriological techniques may be used inside the glove box for culturing and transferring anaerobic bacteria. The box may be heated to 37 C and thus serve as an anaerobic incubator as well, permitting inspection of cultures at any time. Media may be prepared and agar plates may be poured on the laboratory bench in the conventional manner. An overlay of trace amounts of palladium black catalyst over plated agar media reduces the medium to an oxidation-reduction (O-R) potential of - 300 mv within 2 days after introduction into the glove box. In spite of its greater simplicity, the system matched or excelled the roll tube method with respect to all parameters tested, including O-R potential obtainable in the media, O(2) concentration in the gas phase, and efficiency in isolating anaerobic bacteria from the mouse cecum. Comparative studies indicate that the conventional anaerobic jar method was inadequate for the isolation of strict anaerobes from human gingival specimens and from the mouse cecum. This was due to the exposure of specimens and media to air during plating on the open laboratory bench. Anaerobic jars were adequate for maintaining the proper conditions for growth of anaerobic bacteria once these had been established in the glove box.

Animals↗

Supracrestal bone formation around dental implants: an experimental dog study.

To test the osteopromotive activity in large non-spacemaking alveolar bone sites, a total of 20 titanium dental implants were placed superior to a previously modified mandibular alveolar process in five adult beagle dogs. The supracrestal implant position resulted in a mean buccal dehiscence of 5.1 +/- 1.03 mm and a mean supracrestal bone deficit of 2.69 +/- 0.45 mm. Three treatment groups were randomly assigned: group I, ten implants treated with a titanium-reinforced expanded polytetrafluoroethylene (ePTFE) membrane (TR); group II, six implants treated with a standard ePTFE membrane (ST); and group III, four implants that received no membrane (control). Before mucoperiosteal flap closure, the bone surface was perforated and peripheral blood was injected around the implants and underneath the membranes. Clinical evaluation of submerged implant sites showed evidence of complete regeneration of the peri-implant bone defects in groups I and II, minimal bone formation in control group III, and a widening of the ridge in group I. Corresponding histologic examination of undecalcified sections demonstrated large amounts of newly formed bone beneath both types of membranes with a superficial layer of loose connective tissue. Mean gain of supracrestal regenerated bone amounted to 1.82 +/- 1.04 mm (TR group), 1.90 +/- 0.30 mm (ST group), and 0.53 +/- 1.34 mm (control group). Mean bone regeneration at the buccal dehiscences was 3.33 +/- 1.44 mm (TR group), 2.46 +/- 0.51 mm (ST group), and 2.76 +/- 0.84 mm (control group). The TR membranes showed evidence of increased alveolar bone width compared to ST membranes and control sites. These results suggest that supracrestal bone regeneration can successfully be enhanced by a submerged membrane technique in the dog model and that the titanium-reinforced membranes were able to maintain a large, protected space for blood clot stabilization without the addition of bone grafts and produced a larger bone quantity when compared to standard membranes.

Alveolar Bone Loss↗

Osteopromotion as an adjunct to osseointegration.

Osteopromotion to enhance the formation of bone approximating implant surfaces can be obtained using bone regeneration techniques with polytetrafluoroethylene membranes. Treatment of dehiscences and other deficiencies of bone volume allows implants to be successfully placed in regions previously thought to be unsuitable. Bone regeneration is possible in peri-implant osteitis defects if appropriate surgical techniques are used.

Bone Regeneration↗