Duane E. Cutright

The repair of fractures of the orbital floor using biodegradable polylactic acid

Abstract In the repair of blowout fractures, resorption of polylactic acid (PLA) was accomplished by a peculiar phagocytic process involving phagocytic cells, giant cells, and villous projections. PLA tissue compatibility was found to be very good. Clinically, the function of the eye was normal. This study substantiates previous studies concerning the tolerance of tissues for PLA.

Degradation rates of polymers and copolymers of polylactic and polyglycolic acids

Abstract This study has substantiated the following previously reported characteristics of these polymers and copolymers: They are biodegradable. The degradation is accomplished by capillary ingrowth and/or phagocytic foam cells. The degradation is not accompanied by inflammation. The pellets are replaced by fibrous connective tissue and/or bone and marrow tissue. Bone is deposited directly upon and within these materials, thus providing good continuing stabilization. Furthermore, this study has established that, by varying the proportions of PLA to PGA, resorption times can be varied from less than 100 days to periods in excess of 220 days. These materials degrade in the following order: 25 per cent PLA degrades first; 50 per cent PLA degrades second; 75 per cent PLA degrades third; 100 per cent PLA degrades fourth; 100 per cent PGA degrades the slowest. The fast-cooled and slow-cooled polymers with different crystal formations do not affect the degradation rates. The ranges of resorption encompass the times required for fracture fixation. Studies are presently in progress on other proportions of these polymers and on different polymers.

Tissue reaction to the biodegradable polylactic acid suture

Abstract A study of the tissue response to a new suture material indicates that polylactic acid sutures are degradable, that the degradation is gradual and is attended by a giant-cell reaction, and that the diameter of the polylactice acid sutures gradually increases as a result of the inflammatory reaction as well as the infiltration of tissue between the strands.

Reaction of bone to tricalcium phosphate ceramic pellets

Abstract This study indicates that tricalcium phosphate is well accepted by the tissue and may actually contribute mineral salts for the formation of bone at the site as the ceramic is broken down into granules.

Histologic comparison of polylactic and polyglycolic acid sutures

Abstract Comparative studies were carried out to determine soft-tissue reactions and speeds of biodegradation of polylactic acid (PLA) and polyglycolic acid (PGA) sutures in rats. These sutures were placed in the posterior aspects of the thigh muscles, and the animals were killed intermittently through a 90-day postoperative period. The results of the experiment indicate that both PGA and PLA may be acceptable for use as a suture material.

Effectiveness of pulsating water jet lavage in treatment of contaminated crushed wounds.

Abstract Facial crush wounds in 200 albino rats were contaminated with soil containing K pneumoniae, Ps aeruginosa, Pr mirabilis and Staph aureus. The wounds in the control group were irrigated with water using a bulb syringe. In the experimental group the wounds were lavaged with a pulsating water jet. The results indicate that the pulsating jet lavage was much more effective in reducing the bacterial population and in the removal of necrotic tissue and foreign particles from the wounds than was irrigation with a bulb syringe. The amount and extent of the inflammatory reaction and abscess formation was found to be directly related to the amount of foreign material remaining in the wound. Early reduction of bacterial concentration in the wound by pulsating water jet lavage resulted in faster elimination of all bacteria and accelerated wound healing.

Evaluation and comparisons of biodegradable substances as osteogenic agents

This study compared the osteogenic potential and tissue compatibility of biodegradable copolymers--PLA/PGA--and a biodegradable ceramic--Ca3(PO4)2. These compounds were placed in experimentally created defects in rat tibias, both in combination and singly, and evaluated at 14, 28, and 42 days. The ceramic served as a format to result in uniform osteogenesis throughout the defect. The copolymer implants resulted in a more gradual bone formation, progressing slowly from the would peripheries. The ceramic and copolymer combination behaved little differently from the copolymer alone. All experimental materials were extremely tissue tolerant, with minimal inflammation and no foreign-body reactions.

Tissue reaction to intrabony ceramic implants

Abstract It is apparent from the present study that phosphate-bonded alumina ceramic is well tolerated by tissues, does not elicit a foreign-body reaction, is rapidly infiltrated by connective tissue and bone marrow, and forms a latticework upon which osteoid and bone and dentine are deposited. Thus, it would appear that implants of alumina ceramic can be used as bone replacements.

The histopathologic findings in 583 cases of epulis fissuratum

Abstract The histopathologic findings in 583 cases of epulis fissuratum are presented and discussed. The clinical data, such as age, sex, etc., are tabulated. Seventeen different pathologic entities are identified within the fibrous connective tissue of epulis fissuratum tumors. The significance of these findings to the prosthodontist and pathologist is discussed.

Effect of butyl cyanoacrylate on the healing of extraction wounds

Abstract This histologic study was conducted to determine the effect of butyl cyanoacrylate on the healing of extraction wounds. Ninety-six upper first molars were extracted in forty-eight adult rats. Half of the wounds were covered with a spray of butyl cyanoacrylate, while the other half were left uncovered. When animals were killed from 1 to 21 days postoperatively, it was found that the wounds protected with the cyanoacrylate spray consistently showed less inflammatory infiltrate than the control wounds. In addition, it appears that collagenization and epithelization probably occur faster in these treated wounds than in the control wounds. It is postulated that this material should be a valuable aid in the prevention of the so-called “dry socket.”