Biomedical subjects

Chong-Kwan Kim

Publications and source records attributed to Chong-Kwan Kim.

33 records · Page 2Linked to original sources

PubMed2004

Effect of recombinant human bone morphogenetic protein-4 dose on bone formation in a rat calvarial defect model.

BACKGROUND: Bone morphogenetic proteins (BMPs) are being evaluated for periodontal and bone regenerative therapy. The objective of this study was to evaluate the effect of recombinant human bone morphogenetic protein-4 (rhBMP-4) dose on local bone formation in a rat calvaria defect model. METHODS: Calvarial, 8 mm diameter, critical-size osteotomy defects were created in 140 male Sprague-Dawley rats. Seven groups of 20 animals each received either 1) rhBMP-4 (2.5 microg) in an absorbable collagen sponge (ACS) carrier, 2) rhBMP-4 (5 microg)/ACS, 3) rhBMP-4 (2.5 microg) in a beta-tricalcium phosphate (beta-TCP) carrier, 4) rhBMP-4 (5 microg)/beta-TCP, 5) ACS or 6) beta-TCP carrier controls, or 7) a sham-surgery control, and were evaluated by histologic and histometric parameters following a 2- or 8-week healing interval (10 animals/group/healing interval). RESULTS: Surgical implantation of rhBMP-4/ACS and rhBMP-4/beta-TCP resulted in enhanced local bone formation at both 2 and 8 weeks. Within the dose range examined, rhBMP-4 did not exhibit an appreciable dose-dependent response. Defect closure was not significantly different between the rhBMP-4/ACS and rhBMP-4/beta-TCP groups. New bone area of the rhBMP-4/ beta-TCP group was significantly greater than that of the rhBMP-4/ ACS group; however, bone density in the rhBMP-4/ACS group was significantly greater than that in the rhBMP-4/beta-TCP group at 8 weeks (P < 0.05). CONCLUSIONS: rhBMP-4 combined with ACS or beta-TCP has a significant potential to induce bone formation in the rat calvaria defect model. Within the selected rhBMP-4 dose range and observation interval, there appeared to be no meaningful differences in bone formation.

Animals↗

PubMed2004

Periodontal repair in surgically created intrabony defects in dogs: influence of the number of bone walls on healing response.

BACKGROUND: The objective of this study was to histologically evaluate periodontal healing following flap surgery in intrabony periodontal defects to determine the influence of the number of bone walls on periodontal regeneration. METHODS: One-, 2-, and 3-wall intrabony periodontal defects were surgically produced at the proximal aspect of mandibular premolars in either right or left jaw quadrants in six beagle dogs. Mucoperiosteal flaps were positioned and sutured to their presurgery position following defect preparation. The animals were euthanized at 8 weeks post-surgery, and block sections of the defect sites were collected for histologic and histometric analysis. RESULTS: Bone and cementum regeneration was positively correlated to the number of bone walls limiting the intrabony periodontal defects. The junctional epithelium averaged (+/- SD) 1.5 +/- 0.2, 1.2 +/- 0.3, and 0.9 +/- 0.2 mm for the 1-, 2-, and 3-wall defects, respectively, with the 3-wall defects being significantly different from the 1-wall defects (P <0.05). Cementum regeneration averaged 1.2 +/- 0.6, 2.0 +/- 0.6, and 2.8 +/- 0.5 mm for the 1-, 2-, and 3-wall defects, respectively; all groups were significantly different from each other (P <0.05). Bone regeneration averaged 1.5 +/- 0.5, 1.7 +/- 0.6, and 2.3 +/- 0.5 mm for the 1-, 2-, and 3-wall defects, respectively, with the 3-wall defects being significantly different from the 1-wall defects (P <0.05). CONCLUSIONS: The results suggest that the number of bone walls is a critical factor determining treatment outcomes in intrabony periodontal defects. One- and 3-wall intrabony defects appear to be reproducible models to evaluate candidate technologies for periodontal regeneration.

Alveolar Bone Loss↗

PubMed2004

Inhibition of cyclosporin A-induced gingival overgrowth by azithromycin through phagocytosis: an in vivo and in vitro study.

BACKGROUND: The objective of the present study was to investigate the effect of cyclosporin A (CsA) and azithromycin (AZI) on collagen metabolism in the gingiva of rats. METHODS: Fifty 6-week-old male Sprague-Dawley (SD) rats (weight 120 to 150 g) were randomly distributed into five groups. All groups received various drugs via gastric feeding for 7 weeks. The first group (Mo group) received mineral oil for 7 weeks as a control; the CsA group received CsA in mineral oil for 7 weeks (dosage 30 mg/kg); the CsA/Mo group received CsA in mineral oil for 6 weeks and mineral oil only for the seventh week; the CsA/AZI group received CsA in mineral oil for 6 weeks and AZI (dosage 10 mg/kg) in mineral oil simultaneously with CsA in the seventh week; and the Mo/AZI group received mineral oil for 6 weeks and AZI in mineral oil for the seventh week. All animals were sacrificed for clinical and histological analyses. Gingival fibroblasts were cultured at the fourth passage, and the amount of collagen was measured. Type I collagen and collagenase mRNA were measured by reverse transcription-polymerase chain reaction. Collagen phagocytosis assay also was performed. RESULTS: Clinically, CsA induced gingival overgrowth in rats, whereas AZI reduced gingival overgrowth. Histological results of the CsA group showed a marked increase of tissue volume compared to the other groups. High collagen amounts were found when gingival overgrowth was induced. However, type I collagen mRNA and collagenase mRNA expressions did not statistically differ among groups. Phagocytosis assay showed that CsA decreased phagocytic activity of gingival fibroblasts, whereas AZI increased the activity. These results suggest that the induction and reduction of CsA-induced gingival overgrowth were closely associated with phagocytic activity. CONCLUSION: Cyclosporin A decreases collagen degradation by lowering phagocytic activity of rat gingival fibroblasts. Azithromycin partially compensates for this lowered phagocytic activity.

Animals↗

PubMed2004

Effect of the carbon dioxide laser on the clinical parameters and crevicular IL-1beta when used as an adjunct to gingival flap surgery.

OBJECTIVE: This study evaluated the effect of a carbon dioxide (CO2) laser treatment on the clinical parameters and crevicular Interleukin-1 (IL-1beta) levels when used in combination with gingival flap surgery. METHODS: Twelve patients with moderate to advanced periodontitis were selected for this study. Three quadrants in each patient were randomly assigned to one of the following study groups: 1) flap surgery only as the (control); 2) flap surgery and laser treatment using an energy level of 0.8 W as (group 1); 3) flap surgery and laser treatment using an energy level of 0.5 W as (group 2). The gingival crevicular fluid (GCF) was collected at the baseline and biweekly for 6 weeks and the amount of IL-1beta concentration in the sulcular fluid was measured using an enzyme-linked immunosorbent assay. The clinical parameters such as the probing pocket depth, the clinical attachment level, the gingival recession and the bleeding on probing were recorded at the baseline, 3, 6 months. RESULTS: Marked reductions of the bleeding on probing, the probing pocket depth, the clinical attachment level and a reduction in the crevicular IL-1beta concentration were found in all groups. However, the differences between the groups in terms of bleeding on probing and the probing pocket depth were not significant (p<0.05). The clinical attachment level and the crevicular IL-1beta level were significantly lower in group 1 (0.8 W) than in the control (p<0.05). CONCLUSION: The additional use of a carbon dioxide laser on the root surface during gingival flap surgery may enhance the clinical attachment and reduce the crevicular IL-1beta concentration.

Adult↗

PubMed2003

Impaired healing response of periodontal furcation defects following flap debridement surgery in smokers. A controlled clinical trial.

OBJECTIVES: The purpose of the present parallel-design, controlled clinical trial was to evaluate the treatment outcome of periodontal furcation defects following flap debridement surgery (FDS) procedure in cigarette smokers compared to non-smokers. MATERIALS AND METHODS: After initial therapy, 31 systemically healthy subjects with moderate to advanced periodontitis, who presented at least one Class I or II molar furcation defect, were selected. Nineteen patients (mean age: 40.3 years, 15 males) were smokers (>or=10 cigarettes/day) and 12 patients (mean age: 44.8 years, 3 males) were non-smokers. Full-mouth plaque score (FMPS) and full-mouth bleeding score (FMBS), probing pocket depth (PPD), vertical clinical attachment level (v-CAL), and horizontal clinical attachment level (h-CAL) were assessed immediately before and 6 months following surgery. RESULTS: Overall, statistically significant v-CAL gain was observed in smokers (1.0 +/- 1.3 mm) and non-smokers (1.3+/-1.1 mm), the difference between groups being statistically significant (p=0.0003). In proximal furcation defects, v-CAL gain amounted to 2.3+/-0.7 mm in non-smokers as compared to 1.0+/-1.1 mm in smokers (p=0.0013). At 6 months postsurgery, non-smokers presented a greater h-CAL gain (1.3+/-1.1 mm) than smokers (0.6+/-1.0 mm), with a statistically significant difference between groups (p=0.0089). This trend was confirmed in both facial/lingual (1.4+/-1.0 versus 0.8+/-0.8 mm) and proximal furcation defects (1.2+/-1.3 versus 0.5+/-1.2 mm). The proportion of Class II furcations showing improvement to postsurgery Class I was 27.6% in smokers and 38.5% in non-smokers. After 6 months, 3.4% of presurgery Class I furcation defects in smokers showed complete closure, as compared to 27.8% in non-smokers. CONCLUSIONS: The results of the present study indicated that (1) FDS produced clinically and statistically significant PPD reduction, v-CAL gain, and h-CAL gain in Class I/II molar furcation defects, and (2) cigarette smokers exhibited a less favorable healing outcome following surgery in terms of both v-CAL and h-CAL gain.

Adult↗

PubMed2003

Eight-week histological analysis on the effect of chitosan on surgically created one-wall intrabony defects in beagle dogs.

OBJECTIVE: To evaluate the periodontal tissue regenerative effects of a chitosan/collagen sponge applied to preclinical one-wall intrabony defects surgically created in beagle dogs. MATERIAL AND METHODS: 4 x 4 mm one-wall intrabony defects were surgically created in the bilateral maxillary first and third, and the mandibular second and fourth premolars. The surgical control group received a flap operation only, while the buffer control group was treated afterwards with a phosphate-buffered saline/collagen sponge (CS) and the chitosan group was treated with a chitosan/cs. The subjects were killed 8 weeks after the operation, and a comparative histological examination was performed. RESULTS: The amount of junctional epithelium migration was 2.30+/-1.24 mm in the surgical control group, 1.49+/-1.25 mm in the buffer control group, and 0.26+/-0.59 mm in the chitosan group. A significant difference was exhibited only between the surgical control and the chitosan group (p<0.05). The amount of connective tissue adhesion was 0.68+/-0.60, 1.07+/-0.91, and 0.41+/-0.42 mm in the surgical control, buffer control, and the chitosan group, respectively. The amount of cementum regeneration was 1.42+/-0.49, 1.60+/-0.41, and 3.46+/-0.78 mm in the surgical control, buffer control, and the chitosan group, respectively. A significant difference was seen between the chitosan group and the rest (p<0.01). The amount of alveolar bone regeneration was 1.00+/-0.77, 1.52+/-0.37, and 2.43+/-0.44 mm in the surgical control, buffer control, and the chitosan group, respectively. A significant difference was observed between the chitosan group and the rest (p<0.05). CONCLUSION: The results demonstrate the beneficial effect of the chitosan/cs on the one-wall intrabony defects of beagle dogs. The inhibited apical migration of epithelium and the increase in the amount of new bone and new cementum suggest the potency of chitosan in inducing periodontal tissue regeneration.

Alveolar Bone Loss↗

PubMed2003

Inhibitory effect of procyanidin oligomer from elm cortex on the matrix metalloproteinases and proteases of periodontopathogens.

OBJECTIVES: The purpose of this study was to evaluate a partially purified extract (elm extract) from the Ulmi cortex (Ulmi macrocarpa Hance) and its active ingredient, a mix of procyanidin oligomers (3 to 12 flavan-3-ol monomers, an average molecular weight of 1,518 with an average polymerization degree of 5.3) for a possible inhibitory effect against proteases. BACKGROUND: Host-derived matrix metalloproteinases (MMPs) and bacterial proteases play important roles in the gingival tissue destruction that is a characteristic of periodontitis. The inhibitors of these proteases may be developed into therapeutic agents against periodontitis. METHODS: The inhibitory effects were assessed by gelatin zymography. The MMPs tested were originated from the gingival crevicular fluid (GCF) of adult periodontitis patients and from the conditioned media of cultured periodontal ligament (PDL) cells, which provided the proMMP-2 and activated MMP-2 when treated with a periodontopathogen, Treponema lecithinolyticum. Bacterial enzymes tested were secreted forms from two major periodontopathogens, Porphyromonas gingivalis and Treponema denticola. In addition, the inhibitory effects on trypsin-like enzymes from these two periodontopathogens were assayed by the n-benzoyl-DL-arginine-naphthylamide (BANA) test. RESULTS: The elm extract and the procyanidin oligomer (100-1,000 microg/ml) exhibited potent inhibitory effects on the MMPs in GCF (chiefly MMP-8 and MMP-9), the pro and active forms of MMP-2, and secreted and trypsin-like enzymes from T. denticola and P. gingivalis. CONCLUSIONS: These results suggest that elm cortex should be considered as a potential agent against periodontal diseases, due to its inhibitory action on MMPs and the proteases of periodontopathogens.

Adult↗

PubMed2003

Effect of dexamethasone on root resorption after delayed replantation of rat tooth.

The purpose of this study was to evaluate the effect of dexamethasone after delayed tooth replantation with specific regard to root resorption and ankylosis. In addition, the study was planned to elucidate further the usefulness of the model. Fifty-two maxillary first molar teeth were extracted from 26 Sprague-Dawley white female rats fed 0.4% beta-aminoproprionitrile for 3 days to facilitate the extraction. After extraction, the mesiobuccal root canals were endodontically treated under a microscope to prevent subsequent inflammatory resorption of pulpal origin and were assigned to three groups. Teeth in group 1, the dexamethasone group (n = 22), were demineralized in citric acid (1 min), washed, soaked in 1000 nM dexamethasone solution (3 min), air-dried, and replanted in the original sockets. Total extraoral treatment time for each tooth was controlled to 30 min. Teeth in group 2, the dried-only group (n = 22), were air-dried for 30 min after obturation without any surface treatment and replanted. Teeth in group 3, the immediate group (n = 8), were extracted, not root-filled and replanted immediately into their sockets. All experimental animals were killed at 3 weeks after replantation and evaluated histologically. Forty-three of the 52 teeth were available for histological interpretation. They consisted of six immediate, 18 dried-only, and 19 dexamethasone-treated teeth. The degree of progressive root resorption was significantly less in the dexamethasone-treated group than in the dried-only group (p < 0.05). The dexamethasone-treated group exhibited significantly more bone ankylosis than the dried-only group (p < 0.05). These results indicate that the topical use of dexamethasone may be of value in reducing the degree or rate of progressive root resorption secondary to traumatic avulsion and that the rat is a reasonable model for tooth replantation.

Administration, Topical↗

PubMed2003

The use of implantoplasty and guided bone regeneration in the treatment of peri-implantitis: two case reports.

A variety of treatment modalities have been proposed for the management of peri-implantitis. These are mostly based on empiric experience and use the systemic administration of an antibiotic in conjunction with surgical intervention. To ensure decontamination of the affected implant surface(s), chemical and/or mechanical debridement is used. For textured implant surfaces, detoxification using implantoplasty could also give favorable results when used as part of the procedure. Two cases are reported in which implants developed localized peri-implantitis lesions. Implantoplasty followed by topical tetracycline decontamination was used in conjunction with guided bone regeneration. In both cases, the procedures were effective in arresting disease and regenerating lost bone. These results suggest that the technique holds promise and should be investigated further.

Adult↗

PubMed2003

Effect of recombinant human bone morphogenetic protein-4 with carriers in rat calvarial defects.

BACKGROUND: Bone morphogenetic proteins (BMPs) are being evaluated as candidates for periodontal and bone regenerative therapy. However, the research on recombinant human bone morphogenetic protein-4 (rhBMP-4) has been insufficient to evaluate its capacity to enhance bone formation and its carrier system. The purpose of this study was to evaluate the bone regenerative effect of rhBMP-4 delivered with an absorbable collagen sponge (ACS) or beta-tricalcium phosphate (beta-TCP). We also compared the potential of beta-TCP to that of ACS as a carrier system for rhBMP-4. METHODS: Eight-mm calvarial critical-sized defects were created in 100 male Sprague-Dawley rats. The animals were divided into 5 groups of 20 animals each. The defects were treated with rhBMP-4/ACS (rhBMP-4 at 0.05 mg/ml), rhBMP-4/beta-TCP (rhBMP-4 at 0.05 mg/ml), ACS alone, beta-TCP alone, or left untreated for surgical control. The rats were sacrificed at 2 or 8 weeks postsurgery, and the results were evaluated radiodensitometrically, histologically, and histomorphometrically. RESULTS: The results of radiodensitometric analysis were as follows: the rhBMP-4/ACS and the rhBMP-4/beta-TCP groups were more radiopaque than other groups at both 2 and 8 weeks (P < 0.01). The histologic observations were as follows: in the rhBMP-4/ACS and the rhBMP-4/beta-TCP groups, new bone was evident at the defect sites at 2 weeks and 8 weeks. The results of histomorphometric analysis were as follows: the rhBMP-4/ACS and the rhBMP-4/beta-TCP groups had more bone (%) than other groups at both 2 and 8 weeks (P < 0.01). CONCLUSIONS: Surgical implantation of rhBMP-4/ACS may be used to support bone regeneration in the rat calvarial critical-sized defect, and rhBMP-4/beta-TCP may be able to regenerate bone in the rat calvarial critical-sized defect without complication. In addition, both ACS and beta-TCP may be considered as available carriers for rhBMP-4.

Absorptiometry, Photon↗

PubMed2003

Distribution of periodontal pathogens in Korean aggressive periodontitis.

BACKGROUND: Microbial associations in aggressive periodontitis versus different ethnic origins are substantially unknown. We undertook this study to determine the prevalence of seven putative periodontopathogens in Korean patients and to evaluate microbial differences in localized and generalized aggressive periodontitis patients. METHODS: Thirty-nine aggressive periodontitis patients between 20 and 35 years old (24 males and 15 females; mean age 29.6 years) were selected according to clinical criteria. The patients were subclassified into 17 localized and 22 generalized aggressive periodontitis patients. In each of the 39 individuals, subgingival plaque samples were collected from four diseased teeth (> or = 6 mm probing depth, 156 sites) and one healthy site (< or = 3 mm probing depth, 39 sites). Polymerase chain reaction (PCR) of the 16S ribosomal RNA gene fragments (about 530 bp) of plaque bacteria and their subsequent detection by dot-blot hybridization using specific oligonucleotide probes were performed to determine the presence of seven periodontopathogens. RESULTS: The prevalences were 75% for Actinobacillus actinomycetemcomitans, 94.2% for Tannerella forsythensis (formerly Bacteroides forsythus), 99.4% for Fusobacterium sp., 85.9% for Micromonas micros (formerly Peptostreptococcus micros), 96.8% for Porphyromonas gingivalis, 78.8% for Prevotella intermedia, and 96.8% for Treponema sp. The prevalences of these bacteria were significantly higher in diseased sites than in healthy sites. Logistic regression analysis showed that P. intermedia was more significantly associated with generalized aggressive periodontitis than the localized form, with an odds ratio of 3.28 (95% confidence interval 1.26-8.56, P = 0.015). CONCLUSIONS: Our results demonstrate that the seven periodontal pathogens analyzed are strongly associated with Korean aggressive periodontitis. In particular, P. intermedia are more significantly associated with generalized aggressive periodontitis, a more severe and progressive form, than with localized aggressive periodontitis.

Adult↗

PubMed2002

Cloning and characterization of a major surface protein (MspTL) of Treponema lecithinolyticum associated with rapidly progressive periodontitis.

The gene encoding a major surface protein (MspTL) of Treponema lecithinolyticum, a periodontopathogen, was cloned and sequenced. The mspTL gene has a 1770-bp open reading frame (ORF) encoding a protein of 590 amino acids with a predicted molecular mass of 65 kDa which had a typical prokaryotic signal sequence (19 amino acids). MspTL showed a high level of homology with major sheath protein (MspA) of Treponema maltophilum, phylogenetically the closest relative of T. lecithinolyticum. Southern blot analysis indicated that the mspTL gene exists in a single copy and Northern blot analysis showed that the mspTL transcript is monocistronic. Another ORF located downstream of mspTL was in the same orientation and encoded a putative protein, in which the first N-terminal 291 amino acids were identified. The homologous region of this protein is also a part on the T. maltophilum mspA locus.

Amino Acid Sequence↗

PubMed2002

Effect of recombinant human bone morphogenetic protein-2/absorbable collagen sponge (rhBMP-2/ACS) on healing in 3-wall intrabony defects in dogs.

BACKGROUND: Recombinant human bone morphogenetic protein-2 (rhBMP-2) in an absorbable collagen sponge (ACS) carrier is being evaluated as a candidate therapy for periodontal regeneration. The objective of this study was to evaluate regeneration of alveolar bone and cementum, and associated root resorption and ankylosis following surgical implantation of rhBMP-2/ACS in a canine clinical model. METHODS: Bilateral 3-wall intrabony periodontal defects were surgically induced in the premolar region in the maxilla and mandible in 8 young adult Korean mongrel dogs. The defects in each animal received rhBMP-2/ACS (rhBMP-2 at 0.2 mg/ml, total implant volume/defect approximately 0.1 ml) or buffer/ACS, or served as sham-operated controls. Surgeries were sequenced for each animal to provide postmortem observations following 8- and 24-week healing intervals. Treatment outcomes were evaluated using clinical, radiographic, and histometric parameters. RESULTS: Surgical implantation of rhBMP-2/ACS resulted in accelerated enhanced bone formation in the 3-wall intrabony periodontal defects but in no apparent enhancement of cementum regeneration. rhBMP-2/ACS did not appear to be associated with aberrant healing events such as root resorption and ankylosis under these simulated clinical conditions. CONCLUSIONS: Surgical implantation of rhBMP-2/ACS may be used safely to support regeneration of alveolar bone in intrabony periodontal defects in dogs without aberrant events such as root resorption or ankylosis complicating the regenerative procedure. rhBMP-2/ACS does not appear to have a significant effect on cementum regeneration and formation of a functional periodontal ligament in this model.

Alveolar Bone Loss↗

PubMed2002

The effect of recombinant human bone morphogenetic protein-4 on the osteoblastic differentiation of mouse calvarial cells affected by Porphyromonas gingivalis.

BACKGROUND: A number of studies have shown effective bone regeneration induced by bone morphogenetic proteins (BMPs), but it is not clear whether the presence of periodontopathic bacteria has any significant modulation effect on the bone regeneration ability of BMPs. The present study examined whether pretreatment of mouse calvarial cells with Porphyromonas gingivalis extracts can make a difference in their osteoblastic differentiation exerted by recombinant human bone morphogenetic protein-4 (rhBMP-4). METHODS: Primary mouse calvarial osteoblastic (MCO) cells were cultured until they reached confluence. At confluence, cells were untreated or pretreated with 1 microgram/ml of sonicated P gingivalis extracts (SPEs) for 2 days. After washing, the cells were further incubated in the presence of rhBMP-4 (0 to 100 ng/ml) for 3 days. At the end of the treatment, the cells were harvested and lysed for measurement of the alkaline phosphatase (ALP) activity. Total RNA was extracted, and reverse transcription-polymerase chain reaction (RT-PCR) analysis for expression of ALP mRNA was conducted. The amount of prostaglandin E2 (PGE2) secreted into the culture supernatant was determined using an enzyme immunoassay. RESULTS: The stimulatory effect of rhBMP-4 on ALP activity was observed in both untreated MCO cells and in cells pretreated with 1 microgram/ml of SPEs in a dose-dependent manner. The ALP activities were significantly reduced in the cells pretreated with SPEs at all concentrations of rhBMP-4 used in the study when compared to untreated cells. Similar results were obtained in the RT-PCR analysis for ALP mRNA. Cells pretreated with SPEs released significantly larger amounts of PGE2 than untreated cells, but the treatment with 100 ng/ml of rhBMP-4 had no significant effect on the amount of PGE2 released. These results suggest that the stimulatory effect of rhBMP-4 on osteoblastic differentiation might be significantly reduced by P gingivalis, possibly through the endogenous PGE2 pathway, but rhBMP-4 still has a stimulatory effect on osteoblastic differentiation of mouse calvarial cells affected by P gingivalis. CONCLUSION: Our results suggest that supplemental BMPs would be beneficial for improved treatment of osseous defects, although their biologic effect might be significantly reduced by periodontopathic bacteria.

Alkaline Phosphatase↗

PubMed2002

The effect of safflower seed extract on periodontal healing of 1-wall intrabony defects in beagle dogs.

BACKGROUND: Recent interest in naturally based products has increased. Various herbal extracts are known to have a variety of medicinal properties. Among the various natural medicines, safflower seeds have beneficial effects on various bone diseases such as bone fracture, osteoporosis, and osteodysplasia. In addition, they are known to have anti-inflammatory effects. The objective of this study was to evaluate the effect of a safflower seed extract (SSE) on the regeneration of periodontal tissue in a preclinical 1-wall model in dogs. METHODS: Preclinical 1-wall periodontal defects were surgically created in the mesial aspect of the maxillary third and mandibular fourth premolar and in the distal aspect of the maxillary first and mandibular second premolar, and were randomly assigned to receive SSE/collagen (SSE/Col), phosphate-buffered saline/collagen (buffer control), or root planing only (surgical control). The created 1-wall defect configuration was 4 mm in depth by 4 mm in width. We selected the segment showing the best activity to the osteoblast cells that was sensitive to the formation of calcified nodules among the SSE fractions extracted from various organic solvents. The animals were euthanized at 8 weeks postsurgery, and block sections of the defects were collected for histologic and histometric analysis. RESULTS: The junctional epithelium migration did not show any statistically significant differences among the treatments. In connective tissue adhesion, the SSE/Col group and the buffer control group showed significant differences compared to the surgical control group. New cementum averaged 3.84 +/- 0.57 mm, 3.75 +/- 0.24 mm, and 1.53 +/- 1.22 mm for the SSE/Col group, the buffer control group, and the surgical control group, respectively, with the SSE/Col and buffer control groups significantly different from the surgical control group (P < 0.05). The amount of intrabony cementum in the SSE/Col group was significantly different (P < 0.01) from the surgical control group, but the amount of suprabony cementum did not demonstrate any statistical difference between the different treatments. The amount of new alveolar bone averaged 2.93 +/- 0.70 mm, 2.10 +/- 0.63 mm, and 1.20 +/- 0.65 mm for the SSE/Col group, the buffer control group, and the surgical control group, respectively. The difference in alveolar bone regeneration between the SSE/Col group and the surgical control group was significantly different (P < 0.01). Root resorption was often observed, but no ankylosis was present. CONCLUSION: Wound conditioning with safflower seed extracts may contribute to bone formation but appears to have unpredictable potential for stimulating periodontal regeneration including new cementum.

Alveolar Bone Loss↗