• Journal of Periodontal and Implant Science
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• v.34 no.2
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• pp.393-410
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• 2004

The purpose of this study was to investigate effect of enamel matrix derivative on guided bone regeneration with intramarrow penetration in rabbits. Eight adult male rabbits (mean BW 2Kg) were used in this study. Intramarrow penetration defects were surgically created with round carbide bur(HP long #6) on calvaria of rabbits. Defects were assigned to the control group grafted with mixture of the same quantity of demineralized freeze-dried bone allograft and deproteinized bovine bone mineral. Then, guided bone regeneration was carried out using resorbable membrane and suture. Enamel matrix derivative applied to defects was assigned to the test group. And treated as same manners as the control group. At 1, 2, 3 and 8 weeks after the surgery, animals were sacrificed, specimens were obtained and stained with Hematoxylin-Eosin for light microscopic evaluation. The results of this study were as follows : 1. At 1, 2 and 3 weeks, no differences were observed between the control group and the test group in the aspect of bone formation around bone graft. 2. Proliferation of blood capillary was faster in the test group than in the control group. 3. Bone regeneration in intramarrow penetration was faster in the test group than in the control group. 4. At 8 weeks, new osteoid tissue formation around bone graft was more prominent in the test group than in the control group. From the above results, enamel matrix derivative might be considered as the osteopromotion material and effective in the guided bone regeneration with intramarrow penetration.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.34 no.5
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• pp.293-298
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• 2012

Purpose: The aim of this study was to evaluate the bone regeneration ability of 1% tetracycline (TC)-loaded silk fibroin membrane (SFM), in a rabbit calvarial defect model. Methods: Twenty New Zealand white rabbits were used for this study. Bilateral round defects were made on the rabbit parietal bone, using trephine bur with an 8 mm diameter. TC-loaded SFM or SFM was covered on the right parietal bone defect, and the left parietal bone defects were uncovered for the control. The animals were humanely sacrificed at 4 or 8 weeks postoperatively. A micro-computerized tomography (${\mu}$-CT) of each specimen was taken for analysis of bone regeneration. Hematoxylin and Eosin stain were done to observe histological findings. Results: From the ${\mu}$-CT results, regenerated bone volume ($mm^3$) of 1% TC-loaded SFM, SFM, and control were $7.80{\pm}5.87$, $8.79{\pm}3.44$, and $10.61{\pm}5.3$ at 4 weeks postoperatively, respectively (P>0.05). Regenerated bone volume ($mm^3$) of 1% TC-loaded SFM, SFM, and control were $36.56{\pm}8.50$, $25.86{\pm}8.17$, and $19.09{\pm}5.07$ at 8 weeks postoperatively, respectively (P<0.05). Conclusion: The 1% TC-loaded SFM showed more bone regeneration than the SFM and the uncovered control, in guided bone regeneration.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.25 no.1
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• pp.39-49
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• 1995

This study was performed to determine the each location of lesions in the maxillary sinus and to evaluate the relationship between the floor of the antrum and the apical regions of teeth by the comparison of the panoramic view and panoramic sinus view. For this study, experimentally with two dry skulls, jelly balls of 8mm and 15mm in diameter containing a short wire for the radiopacity similar to the cyst and clinically 5 patients having mucosal cyst in the antrum and 10 patients having periapical lesion of molar were used. The experimental cystic lesions were simulated with jelly ball being attached in turn to each wall of the antrum. The radiolucent periapical lesions of upper molars were formed by using round bur and the radiopaque periapical lesions were simulated by filling the former lesions with lead foil. Each panoramic view and each panoramic sinus view of the experimental lesions and patients were obtained by using panoramic machine and analyzed. The obtained results were as follows : 1. On the panoramic sinus view, the innominate line was approximately coincided with the most lateral portion of the antrum and the posterior wall appeared as the narrow area at the mesial side of the innominate line. The anterior wall occupied totally the mesial side of the innominate line, and the medial wall occupied the mesial half of the antrum. 2. In all cases of experimental cystic lesion attached to each wall of the antrum, the location of each lesion was able to be determined by applying Tube shift technic. 3. The palatal root and mesiobuccal root of the molar appeared as being transposed each other mesiolaterally on the panoramic and panoramic sinus views. 4. The panoramic sinus view was superior to the panoramic view in revealing the relationship between the floor of the antrum and the periapical lesion.

• Restorative Dentistry and Endodontics
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• v.28 no.3
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• pp.203-208
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• 2003

The purpose of this study was to evaluate the effect of salivary contamination of teeth on bonding efficacy of self-priming and self-etching DBSs. The materials used were Single Bond(SB, self-priming system, 3M), Unifil Bond(UB, self-etching system, GC), and Scotchbond Multi-Purpose Plus(SM, 3M) as control. Forty five human molars randomly allocated to three groups as dentin bonding systems tested and embedded in epoxy resin. Then the specimens were wet-ground to expose flat buccal enamel surface or flat occlusal dentin surface and cut bucco-lingually to form two halves with slow speed diamond saw. One of them was used under non-contamination, other under contamination with saliva. The bonding procedure was according to the manufacturer's directions and resin composite(Z-100, 3M Dental Products, St. Paul, MN) was built-up on the bonded surface 5mm high. The specimens were ground carefully at the enamel-composite interface with fine finishing round diamond bur to create an hour-glass shape yielding bonded surface areas of $1.5{\pm}0.1\textrm{mm}^2$. The specimens were bonded to the modified microtensile testing apparatus with cyanoacrylate, attached to the universal testing machine and stressed in tension at a CHS of 1mm/min. The tensile force at failure was recorded and converted to a tensile stress(MPa). Mean values and standard deviations of the bond strength are listed in table. One-way ANOVA was used to determine significant difference at the 95% level. The bond strength of SBMP and SB were not affected by salivary contamination, but that of UB was significantly affected by salivary contamination. These results indicate that DBSs with total etch technique seems less likely affected by salivary contamination in bonding procedure.

• Restorative Dentistry and Endodontics
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• v.22 no.1
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• pp.93-109
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• 1997

Finding a right repair material for furcation perforation is one of the major issues in clinical endodontics. In this experiment, three materials, calcium sulfate, amalgam, and calcium hydroxide were tested for perforated furcation repair. Sixty premolars and molars of five dogs were used. A #4 round bur was used to create the perforation. All experimental teeth were divided into two repair-time groups. One was immediate-repair group, where the perforation was repaired immediately, the other was delayed-repair group, where the perforation was left open for four weeks and then repaired with the same manner as in the immediate-repiar group. All chamber openings were sealed with amalgam and then radiographed. The animals were sacrificed at eighth week following the repair procedure. Radiographic evaluation for furcal bone destruction was done. Histologic evaluation was ranked as 0,1,2,3 according to the inflammation degrees. New bone formation was also recorded. The following conclusions were drawn within the limits of the experimental results: 1. In immediate-repair group, no significant differences existed between the materials. 2. In delayed-repair group, calcium sulfate showed significantly less furcal bone destruction and lower inflammation degree than amalgam.(p<0.05) 3. Overextruded specimens showed more severe inflammation than unextruded specimens. 4. Most of the specimens showed certain degrees of inflammatory reaction and incomplete hard tissue healing. 5. In delayed-repair group, treated group showed less inflammation than untreated control group.

• Imaging Science in Dentistry
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• v.41 no.4
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• pp.143-150
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• 2011

Purpose : The aim of this study was to compare the diagnostic accuracy of cone-beam computed tomography (CBCT) images and bitewing images in detection of secondary caries. Materials and Methods : One hundred and twenty proximal slots of Class II cavities were randomly prepared on human premolar and molar teeth, and restored with amalgam (n=60) and composite resin (n=60). Then, artificial secondary caries lesions were randomly created using round steel No. 4 bur. The teeth were radiographed with a conventional bitewing technique and two CBCT systems; Pax-500ECT and Promax 3D. All images were evaluated by five observers. The area under the receiver operating characteristic (ROC) curve ($A_z$) was used to evaluate the diagnostic accuracy. Significant difference was tested using the Friedman test (p value<0.05). Results : The mean $A_z$ values for bitewing, Pax-500ECT, and Promax 3D imaging systems were 0.882, 0.995, and 0.978, respectively. Significant differences were found between the two CBCT systems and film (p=0.007). For CBCT systems, the axial plane showed the greatest $A_z$ value. Conclusion : Based on the design of this study, CBCT images were better than bitewing radiographs in detection of secondary caries.

• Restorative Dentistry and Endodontics
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• v.22 no.2
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• pp.710-719
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• 1997

Aucubin, an iridoid glucoside, which is isolated from Aucuba japonica, has some biological effects. This study was to investigate the effect of aucubin on the remainig pulp tissues after pulpotomy. Mongrel dog's coronal pulps were mechanically exposed with a sterile round bur and excised with sterile sharp excarvator. After bleeding was controlled, in control group, $Ca(OH)_2$ powder was applied on the remaining pulps and the cavities were sealed with Z.O.E. cement. In experimental group 1, mixed powder with $Ca(OH)_2$ and aucubin(l : 1 by weight) was applied on the pulpotomized pulp surfaces. After the cavities were covered with sterile aluminum foil, they were sealed with Z.O.E. cement. In experimental group 2, only aucubin powder was applied on the remaining pulps and then they were treated the same as experimental group 1. In the all groups, the pulps were histopathologically observed by light microscope at the time intervals of 1, 2 and 4 weeks after experiment. The results were as follows : 1. In control and experimental groups, mild vascular congestion and bleeding were found in most of the specimens. Less inflammatory infiltration was observed in experimental groups than in control group. 2. Dentin bridge formation was found after 1 week at both control and experimental group 1. Dentin birdge had discontinuous osteodentin like appearance or contained some dentin chips. In experimental group 2, dentin bridge was not seen. 3. The coagulation necrosis layer on the remaining pulp tissues was seen in all groups. In experimental group 2, the thickest layer was observed. And in control group, coagulation necrosis layer was similar as in experimental group 1.

• Restorative Dentistry and Endodontics
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• v.32 no.6
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• pp.483-490
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• 2007

This report describes clinical cases of a palato-gingival groove on a maxillary lateral incisor with associated localized periodontal disease and pulp necrosis. The tooth of the first case was extracted because of severe bone destruction. The palato-gingival groove of the second case was eliminated using a round bur, and the resulting defect was filled with synthetic graft and covered by an absorbable membrane. Both diagnosis and treatment of palato-gingival groove were very difficult and usually extraction of the involved tooth is the treatment of choice. but combined endodontic-peri-odontic treatment allowed the tooth to be saved.

• Journal of Periodontal and Implant Science
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• v.30 no.4
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• pp.793-803
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• 2000

Procedures for treatment of molar furcation invasion defects range from open flap debridement, apically repositioned flap surgery, hemisection, tunneling or extraction, to regenerative therapies using bone grafting or guided tissue regenerative therapy, or a combination of both. Several clinical evaluations using regenerative techniques have reported the potential for osseous repair of treated furcation invasions. Regenerative treatment of maxillary molars are more difficult due to the multiple root anatomy and multiple furcation entrances therefore, purpose of this study was to evaluated histologically self-curing glass-ionomer cement and light-curing glass-ionomer cement as a barrier in the treatment of a bi-furcated maxillary premolar. Five adult beagle dogs were used in this experiment. With intrasulcular and crestal incision, mucoperiosteal flap was elevated. Following decortication with 1/2 high speed round bur, degree II furcation defect was made on maxillary third(P3), forth(P4) and fifth(P5) premolar. 2 month later experimental group were self-curing glassionomer cement and light-curing glassionomer cement. After 4, 8 weeks, the animals were sacrificed by vascular perfusion. Tissue block was excised including the tooth and prepared for light microscope with Gomori's trichrome staining. Results were as follows. 1. In all experiment group, there were not epithelial down growth and glass ionomer cement were encapsulated connective tissue. 2. In 4 weeks experiment I group slighly infiltrated inflammatory cells but not disturb the new bone or new cementum formation. 3. In 8 weeks, experiment groups I, II were encapsulated fine connective tissue. 4. Therefore glass-ionomer cement filling to the grade III maxillary furcations with multiple root anatomy and multiple furcation entrances were possible clinical methods and this technique is useful method for Maxillary furcation involvement.

• Journal of Periodontal and Implant Science
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• v.30 no.4
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• pp.803-814
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• 2000

Current acceptable methods of promoting periodontal regeneration are basis of removal of diseased soft tissue, root treatment, guided tissue regeneration, graft materials, biological mediators. Platelet Rich Plasma have been reported as a biological mediator which regulate activities of wound healing progress including cell proliferation, migration, and metabolism. The purpose of this study is to evaluate the possibility of using the Platelet Rich Plasma as a regeneration promoting agent for furcation involvement defect. Five adult beagle dogs were used in this experiment. With intrasulcular and crestal incision, mucoperiosteal flap was elevated. Following decortication with 1/2 high speed round bur, degree II furcation defect was made on mandibular third(P3), forth(P4) and fifth(P5) premolar. 2 month later experimental group were PRP plus bovine bone and bovine bone only. After 4, 8 weeks, the animals were sacrificed by perfusion technique. Tissue block was excised including the tooth and prepared for light microscope with Gomori's trichrome staining. At 4 weeks after surgery, there were rapid osteogenesis phenomenon on the defected area of the Platelet Rich Plasma plus bovine bone group and early trabeculation pattern was made with new osteoid tissue produced by activated osteoblast. Bone formation was almost completed to the fornix of furcation by 4 weeks after surgery. In conclusion, Platelet Rich Plasma can promote rapid osteogenesis during early stage of periodontal tissue regeneration.