The Evaluation of Alpha Plaster of Paris as a Osteoconductive Material in the Adult Cat Calvarium

1991 ◽  
Vol 252 ◽  
Author(s):  
N. W. Knuckey ◽  
H. Saskin ◽  
R. Yanagasawa ◽  
M. Flanagan

Spontaneous new bone formation does not occur in the adult calvarium. In humans, cranial defects may require repair for brain protection, headaches or cosmetic. Over the years the search for the ideal cranioplasty material to repair such cranial defects has been extensive. We report an evaluation of alpha plaster of paris as an osteoconductive material in a cat craniectomy defect.Adult cats of either sex were anesthetized with ketamine/halothane and a 15mm biparietal craniectomy defect created. The right side was filled with alpha plaster of paris and the left served as a control. There were 4 animals in each time cohort and animals were sacrificed at 6 weeks, 6 or 12 months. The cranium was removed, fixed, stained, histologically studied and analysised for the percentage of trabecular bone formation. At all durations the control defects were bridged by proliferative fibrous tissue membrane and less than 1% trabecular bone. At six weeks the plaster of paris filled defects were either totally or nearly totally replaced by new bone formation. The plaster was completely resorbed. At 6 wks there was 28% trabecular bone which increased to 93% at 52 wks. Our experiments demonstrate the oeteoconductive potential of alpha plaster of paris in the adult calvarium. This material needs to be evaluated in humans to ascertain its potential as a biocompatible cranioplasty material.

2017 ◽  
Vol 22 (2) ◽  
pp. 116-123 ◽  
Author(s):  
Takefumi Kamakura ◽  
Daniel J. Lee ◽  
Barbara S. Herrmann ◽  
Joseph B. Nadol Jr.

The Cogan syndrome is a rare disorder characterized by nonsyphilitic interstitial keratitis and audiovestibular symptoms. Profound sensorineural hearing loss has been reported in approximately half of the patients with the Cogan syndrome resulting in candidacy for cochlear implantation in some patients. The current study is the first histopathologic report on the temporal bones of a patient with the Cogan syndrome who during life underwent bilateral cochlear implantation. Preoperative MRI revealed tissue with high density in the basal turns of both cochleae and both vestibular systems consistent with fibrous tissue due to labyrinthitis. Histopathology demonstrated fibrous tissue and new bone formation within the cochlea and vestibular apparatus, worse on the right. Severe degeneration of the vestibular end organs and new bone formation in the labyrinth were seen more on the right than on the left. Although severe bilateral degeneration of the spiral ganglion neurons was seen, especially on the right, the postoperative word discrimination score was between 50 and 60% bilaterally. Impedance measures were generally higher in the right ear, possibly related to more fibrous tissue and new bone found in the scala tympani on the right side.


1977 ◽  
Vol 86 (4_suppl) ◽  
pp. 1-39 ◽  
Author(s):  
Gary K. Thomas

This animal experimental study (144 cats) was designed to allow observation of the healing processes at the oval window following stapedectomy during the first two postoperative weeks. The first 61 animals (Series I) had no oval window cover except for a blood clot which might form spontaneously. The second 64 animals (Series II) had Gelfoam® as a cover to the oval window following stapedectomy. A third series of 19 animals had temporalis fascia used as the oval window cover, and these ears were studied histologically for up to nine weeks. The unoperated ear acted as a control for the operated ear in all animals and after the animals were killed, both temporal bones were decalcified, imbedded in celloidin, serially sectioned at 20μ, and every tenth section stained and mounted for histologic study. It was observed that oval window closure was effected by endosteal, periosteal, and fibrous tissue proliferation from the traumatized tissues about the oval window fenestra, and that this process was facilitated by the presence of some type of scaffolding material such as a blood clot or Gelfoam®. Temporalis fascia placed in the oval window was observed to be rapidly incorporated into a much thicker oval window neomembrane and to seal the fenestra promptly. Partial removal of the footplate also facilitated more rapid closure of the smaller oval window fenestra, but fibrous tissue and new bone formation was noted to form about bony fragments still attached at the oval window level. Free bony fragments within the vestibule were not observed to stimulate new bone formation. Suppuration was observed most frequently in Series I (no oval window cover), with 67.8% of these animals having some degree of otitis media. In Series II (Gelfoam® cover) 20.6% had otitis media, and in Series III (temporalis fascia) 21% had middle ear infection. Suppuration markedly impaired but did not completely prevent the oval window reparative processes. Animals having some type of oval window cover were noted to have a lesser incidence of suppurative labyrinthine involvement when otitis media was present. Other labyrinthine complications were observed, including endolymphatic hydrops, Wittmaack's hypotonic atrophy, as well as RBC, fibrin, and albuminous precipitates in the labyrinth. Hypotonic atrophy was observed in a high incidence of animals having rupture of one or more endolymphatic structures, suggesting a mechanical mechanism as one possible explanation for this condition. Hypotonic atrophy may represent the end-stage (collapse) in the fluctuant endolymphatic ballooning of hydrops which is seen when saccular or Reissner's membrane ruptures have occurred.


2002 ◽  
Vol 13 (2) ◽  
pp. 92-96 ◽  
Author(s):  
Luciana Ibara Yugoshi ◽  
Miguel Angel Sala ◽  
Luiz Guilherme Brentegani ◽  
Teresa Lúcia Lamano Carvalho

The purpose of the present study was to investigate if diclofenac administration interferes with the time course of alveolar wound healing in rats. Forty-two Wistar rats were used, 21 rats received 10 mg/kg/day of diclofenac one day before and 4 days after extraction of the right maxillary incisors and 21 rats received saline. The animals were sacrificed 7, 14 and 21 days after tooth extraction. Progressive new bone formation and a decrease in the volume fraction of blood clot and connective tissue from 1 to 3 weeks after tooth extraction was quantified using the histometric point-counting method. Diclofenac treatment caused a significant delay in new bone formation in association with an impairment of blood clot remission/organization.


1988 ◽  
Vol 69 (2) ◽  
pp. 269-275 ◽  
Author(s):  
Charles E. Rawlings ◽  
Robert H. Wilkins ◽  
Jacob S. Hanker ◽  
Nicholas G. Georgiade ◽  
John M. Harrelson

✓ The materials ordinarily used to reconstruct bone defects in the calvaria and facial bones either are difficult to shape, are partially resorbed by the body, or are likely to become infected if used near a contaminated area such as the frontal sinus. Calcium sulfate hemihydrate (plaster of Paris) has been known for years to have excellent reparative qualities in bone defects, but ordinarily it is quickly resorbed. Consequently, a new material, a composite of a dense form of plaster of Paris and hydroxylapatite, was devised to provide nonabsorbable hydroxylapatite particles for bone to form around and within during the phase of plaster absorption. Two types of this material were evaluated in cranial defects in cats. Each of the plaster of Paris/hydroxylapatite mixtures was placed into a surgically unroofed frontal sinus and into a contralateral parietal trephine hole in a group of 32 cats. Two cats in each group succumbed to anesthesia, leaving two sets of 30 cats. During the entire follow-up period there was only one other death, with no evidence of wound infection, wound dehiscence, implant rejection, or cerebral dysfunction among the survivors. The cats in each group were sacrificed at 1, 2, 3, 5, 7, 8, 9, 10, or 12 months after operation. Following sacrifice, both the frontal and parietal defects were exposed and examined visually, histologically, and with histomorphometric analysis for new bone formation. New bone formation was present as early as 1 month after operation and continued to increase during the 12 months of the study. Based upon these osteogenic qualities, the ease of shaping the composite, and the lack of infection in the frontal sinus region, it is concluded that this substance could be a valuable new material for human cranioplasty.


2011 ◽  
Vol 37 (5) ◽  
pp. 511-518 ◽  
Author(s):  
Flaviana Soares Rocha ◽  
Lara Maria Alencar Ramos ◽  
Jonas Dantas Batista ◽  
Darceny Zanetta-Barbosa ◽  
Eloísa Amália Vieira Ferro ◽  
...  

Autogenous bone tissue has regeneration potential; however, this capacity may not be sufficient in larger bone defects. The aim of this study is to histologically evaluate anorganic bovine bone grafts (GenOx Inorg) with or without platelet-rich plasma (PRP). Two bone lesions were created in calvaria of 12 rabbits. The 24 surgical lesions were separated into 3 groups: coagulous, anorganic, and anorganic with PRP. At the 4-week time point, the animals were euthanized and the grafted area removed, fixed in formalin 10% with phosphate buffered saline, 0.1 M, and embedded in paraffin. The histologic parameters analyzed were new bone filling the defect area, presence of giant cells and particles of the graft, and new bone formation associated with the particles. In the coagulous group, defects were filled with fibrous tissue that attached the periosteum and little bone neoformation in the periphery. In anorganic groups with or without PRP, little new bone formation in the periphery of the defect was observed; however, in the center of some defects there was new bone. Moderate presence of giant cells and little new bone formation was associated with the innumerous graft particles. Histologic results revealed no statistically significant differences among the defects new bone fill between the studied groups (P  =  .64). There was no significant difference in the number of giant cells (P  =  .60), graft particles (P  =  .46), and new bone formation around graft particles (P  =  .26), whether PRP was added or not. Anorganic bone, isolated or mixed with PRP, was biocompatible and osteoconductive, while maintaining bone volume.


2007 ◽  
Vol 330-332 ◽  
pp. 1311-1314 ◽  
Author(s):  
S.G. Kim ◽  
O.J. Park ◽  
Sung Chul Lim ◽  
Chun Sik Bae

This studied determined the clinical effect of antibiotic use at the site of bone defect restoration in patients with osteoporosis, using tooth ash and plaster of Paris in ovariectomized rats. Forty-eight rats were assigned to four groups randomly and each group was further divided into 4 and 8 weeks after implantation. Histologic sections of the defects were obtained after surgery for histomorphometric analysis. Comparing each week, a significant difference was seen in bone formation by 4 weeks. Compared to controls, new bone formation increased significantly with tooth ash and saline, tooth ash and gentamicin, and tooth ash and gentamicin after ovariectomy. Tooth ash and saline resulted in the best bone formation. The degree of new bone formation was slightly lower when tooth ash and gentamicin were used compared to when tooth ash and saline were used. When tooth ash and gentamicin were compared according to ovariectomy, bone formation was significantly inhibited by ovariectomy at 4 weeks, while no significant difference was seen at 8 weeks.


2013 ◽  
Vol 7 (1) ◽  
pp. 18-24 ◽  
Author(s):  
Jeppe Barckman ◽  
Jorgen Baas ◽  
Mette Sørensen ◽  
Joan E Bechtold ◽  
Kjeld Soballe

Purpose: Periosteum provides essential cellular and biological components necessary for fracture healing and bone repair. We hypothesized that augmenting allograft bone by adding fragmented autologous periosteum would improve fixation of grafted implants. Methods: In each of twelve dogs, we implanted two unloaded cylindrical (10 mm x 6 mm) titanium implants into the distal femur. The implants were surrounded by a 2.5-mm gap into which morselized allograft bone with or without addition of fragmented autologous periosteum was impacted. After four weeks, the animals were euthanized and the implants were evaluated by histomorphometric analysis and mechanical push-out test. Results: Although less new bone was found on the implant surface and increased volume of fibrous tissue was present in the gap around the implant, no difference was found between treatment groups regarding the mechanical parameters. Increased new bone formation was observed in the immediate vicinity of the periosteum fragments within the bone graft. Conclusion: The method for periosteal augmentation used in this study did not alter the mechanical fixation although osseointegration was impaired. The observed activity of new bone formation at the boundary of the periosteum fragments may indicate maintained bone stimulating properties of the transplanted cambium layer. Augmenting the bone graft by smaller fragments of periosteum, isolated cambium layer tissue or cultured periosteal cells could be studied in the future.


2008 ◽  
Vol 20 (04) ◽  
pp. 239-248 ◽  
Author(s):  
Shyh Ming Kuo ◽  
Li-Chun Lin ◽  
Pei Hua Tsai ◽  
Gregory Cheng-Chie Niu ◽  
Shwu Jen Chang

Two kinds of chitosan/β-TCP microspheres were prepared; one was by a traditional emulsion technique (Group A), and the other was by a high-voltage electrostatic system (Group B). Both of the microspheres exhibited good sphericity and the β-TCP fine particles were well trapped inside the chitosan based particles. After 60-day shaking, Group A and Group B degraded by about 40% and 80% of initial weight, respectively. Two models of bone defects were created in rabbits included for a series of randomized blind pilot study. In the cranial model, two equal 10 mm diameter cranial defects were created. In condyle model, two equal 5 mm femur condyle defects were created on each hind leg, and underwent the same grafting treatment. After 4 weeks of implantation, both the cranial and condyle sites filled with Group A were shown to be surrounded by fibrous tissues with the presence of osteoblasts. In Group B, only condyle site showed the presence of osteoblasts. In contrast, fibrous tissue formation was seen on the control group after 4 weeks of healing. After 8 weeks of implantation, the condyle sites filled with Group A and Group B showed the presence of new bone formation as compared to control group. However, there was no obvious new bone formations in the cranial sites filled with both Group A and Group B. The same events were observed in the cranial sites after 12 weeks of implantation. In contrast, new bone formation was seen on the condyle sites in all three groups after 12 weeks of implantation.


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