safety 11 . Jensen et al. 12 compared the bone healing achieved using autografting, anorganic bovine bone-derived mineral (ABBM), and synthetic b-tricalcium phosphate (b-TCP) in intraosseous defects in the mandible of minipigs. Autografting resulted in faster bone regeneration than grafting with either ABBM or synthetic b- TCP in the early healing phase. Although newly formed bone ultimately regenerated in all defects after 8 weeks regardless of the graft material used, autografting resulted in increased osseous maturity during all healing periods. Other studies have also shown that autogenous bone can induce faster and more mature bone regeneration in the initial healing period of lateral ridge augmentation 13,14 . In spite of these advantages, the unpredictable resorption rate, limited availability, and patient morbidity limit its common use. Bone substitutes may overcome these potential shortcomings, and a good solution when autogenous bone is harvested may be combining that harvested bone with an osteoconductive bonesubstitute 15 .
2 Department of Orthopedic Surgery & Rare Diseases Institute, Korea University Medical Center, Guro Hospital, Seoul,
3 Department of Prosthodontics, Institute for Clinical Dental Research, Korea University Guro Hospital, Seoul, Korea
PURPOSE. This study was performed to investigate the ability of recombinant human-bone morphogenic protein-2 immobilized on a heparin-grafted bone substrate to enhance the osteoblastic functions. MATERIALS AND METHODS. The Bio-Oss � , not coated with any material, was used as a control group. In rhBMP-2-Bio-Oss � group, rhBMP-2 was coated with Bio-Oss � using only deep and dry methods (50 ng/mL, 24 h). In heparinized rhBMP-2-Bio-Oss � group, dopamine was anchored to the surface of Bio-Oss � , and coated with heparin. rhBMP- 2 was immobilized onto the heparinized- Bio-Oss � surface. The release kinetics of the rhBMP-2-Bio-Oss � and heparinized rhBMP-2-Bio-Oss � were analyzed using an enzyme-linked immunosorbent assay. The biological activities of the MG63 cells on the three groups were investigated via cytotoxicity assay, cell proliferation assay, alkaline phosphatase (ALP) measurement, and calcium deposition determination. Statistical comparisons were carried out by one-way ANOVA test. Differences were considered statistically significant at *P<.05 and **P<.001.
The author started the paragraph with the preparation of PRF, however, described the protocol for PRP, continued by saying that “coagulated preparation of 0.3 mL of PRF was obtained by its combination with 0.1 g of calcium chloride” and then finish by saying that
“then graft material was mixed with the coagulated PRP preparation.”
II. Materials and methods
Five male New Zealand white rabbits weighing between 2.5 kg and 3.0 kg were selected as the experimental model. The number of animals was determined from newly formed bone volume data of our previous study 14 and required to have 95% chance of detecting, as significant at the 5% level. Animals were kept in separate cages under standard laboratory conditions with ad libitum access to a diet of standard laboratory pellets and water. Animal selection and care, the preparation procedures, and the surgical protocols were certified by the Institutional Animal Care and Use Committee, Yonsei Medical Center, Seoul, Korea (approval no. 2011-0262).
From histomorphometric analysis, it was found that in the 4-week healing groups, new bone formation was statistically significantly greater in experimental group 1 than control group 1. Based on this result, it can be interpreted that in ex- perimental group 1, more graft materials were substituted with new bone. In other words, bone graft materials coated with even low concentration of ErhBMP-2 (0.05 mg/mL) showed better osteoinductive potential than bone graft ma- terials alone. Although the difference is not statistically sig- nificant, bone graft materials coated with a high concentra- tion of ErhBMP-2 (0.5 mg/mL) also showed better osteoin- ductive potential than the control group. Thus, these findings demonstrate that ErhBMP induces rapid bone formation and remodeling at an earlier stage, and this is consistent with findings of a previous study  that used the rat calvarial de- fect model. On the other hand, in the 4-week healing groups, the remaining graft was statistically significantly less in ex- perimental group 1 than control group 1. This can be inter- preted as showing that more of the bone graft material in ex- perimental group 1 had been substituted with new bone, thereby showing less remaining graft material. Considering the fact that the amount of graft material applied to each group was the same, there might be no difference between experimental group 1 and group 2 in osteoinductive poten- tial. This result is also supported by the results of the 8-week healing groups where MAH was statistically significantly greater in experimental group 1 than group 2, which can be interpreted as showing that the total amount of bone includ- ing new boneand graft materials increased to some extent.
I thank the readers for finding this case report interesting and raising the issue regarding the terminology used. Platelet rich plasma (PRP) was activated with calcium chloride and hence coagulated PRP term has been used here. Fibrin matrix which is achieved with the use of PRP and exogenous activators has been given different terminology in the literature like platelet rich fibrin (PRF) matrix, PRF, platelet gel, PRF clot, PRP gel [1-3]. I agree with the readers that PRF is a widely accepted term for preparation with a natural coagulation pathway earlier known as Choukron's PRF. Hence PRP/PRF gel may be a better alternative term for the preparation as in the present case report. In the past two decades, this area has gone a lot of innovations and modifications . PRF is a broad term that is used for various preparations, protocols and various variables affecting its composition. As there is a lot of heterogeneity regarding the terminology used, to better compare the results and drawing an inference, these terms may be correlated with the methodology used. I am thankful for giving me the opportunity to clarify my intent in this case report.
Previous studies found that HA did not support new bone formation, while the opposite result was found in the present study. This discrepancy is probably due to the use of a block-type bonesubstitute, which not only helps in the formation of new bone but is also more efficient than the particulated type of calcium phosphate bonesubstitute. In addition, block-type bone graft materials allow new bone apposition to occur in parallel with progressive material degradation.The histometric results of our study show that HA particles are not easily absorbed, since the amount of residual HA particles shows only small decreases between 4 and 8 weeks postsurgery.
From histomorphometric analysis, it was found that in the 4-week healing group, new bone formation was statistically significantly greater in the experimental group than the con- trol group. This result is in accordance with previous studies [34-36], as it was thought that bone graft material coated with oligopeptide would promote cell adhesion and cell differen- tiation, providing more favorable conditions for new bone formation. CT volume was also statistically significantly in- creased in the experimental group than the control group, which also supports the idea that bone graft materials with oligopeptide coating have more osteoinductive potential.
Endo-perio lesions are common conditions that are difficult to diagnose. However, if patient’s history is taken carefully and thorough clinical examination is done, these lesions can be treated completely to give favorable outcome. The healing of an endodontic lesion is highly predictable, but the repair or regeneration of periodontal tissues is questionable if associated with it. Recent introduction of growth factors for periodontal treatment provide new opportunities for healing. This case report presents an attempt to evaluate the clinical effectiveness of the combination of PRF and β-TCP as opposed to using these materials alone. The use of autologous platelet preparations like PRF allows the clinician to optimize tissue remodelling, wound healing and angiogenesis by the local delivery of growth factors and proteins. The novel technique described enables the clinicians to gainfully harvest the full regenerative capacity of this autologous biologic material.
(Revised March 11, 2013) (Accepted March 22, 2013)
Abstract For further improvement of osseo-integration of bone crystal with a dental implant, a design optimization study is carried out for various holes inside its body to deliver bioactive materialsand the effect of bioactive material injection on the bone crystal growing. When bioactive material is absorbed, the bone crystal can grow into holes, which would increase the strength of implant bonding as well as a surface integration. The stress concentrations near the uppermost outlet holes were reduced with increasing the number of outlet holes. A design improvement in the uppermost outlet was shown to be effective in reducing the stress concentration. For design parameters under consideration in this study, total area of outlet of 6.38 mm 2 and maximum stress of 1.114 MPa, which corresponds to type 6-C. It is due to the minimization of maximum stress and total area of outlet. The design of the outlet facing down was more effective in reducing the maximum stress value compared with a horizontal symmetry.
Materials and Methods
Thirty specimens from cadavers, 20 men and 10 women, were examined. The cadavers were of Korean descent and had been embalmed after death. The mean age at time of death was 66.7 years, ranging from 58 to 80 years. The cadavers had no history of trauma or surgical procedures associated with the cervical region. Latex (Neoprene, Lot No. 307L146, Barsac, DuPont, France) with a red coloring agent (colorant universel, Templemars, Castorama, France) was injected into all the specimens through the CCA to permit observation of the topographic relationship between the course of the STA and the anterior cervical region surrounding it.
The marginal sealing ability of calcium silicate–based materials is attributed to its ability to produce surface apatite crystals when in contact with the phosphates available in tissue fluids. The crystalline precipitates are formed through interaction of calcium and hydroxyl ions released from set material with phosphates. 28 The apatite crystals formed have been identified as calcium- deficient B-type carbonated apatite precipitates produced via an amorphous calcium phosphate phase. 29 Biodentine shows apatite formation after immersion in phosphate solution, indicative of its bioactivity. 30 Dentine may uptake several elements released from bioactive materials, and such a phenomenon may cause chemical and structural modification in dentine. Han and Okiji compared calcium and silicon uptake by adjacent root canal dentine in the presence of phosphate buffered saline using Biodentine and ProRoot MTA. The results showed that both materials formed a tag-like structure composed of the material itself or calcium- or phosphate rich crystalline deposits. The thickness of the calcium and silicon -rich layers increased Table 1. Clinical indications of Biodentine 22,23
Abstract In order to improve osseo-integration of a dental implant with bone crystal we studied an implant with holes inside its body to deliver bioactive materials based on a proposed patent. After bioactive material is absorbed, bone crystal can grow into holes to increase implant bonding in addition to surface integration. The larger cross section area of outlet holes showed the less values of the maximum stress, and the stress concentrations near the uppermost outlet holes were also reduced with an increasing number of outlet holes. The conclusion, that the uppermost outlet design improvement was most effective to reduce the stress concentration and improve the growth rate of bone crystal, could be drawn. After the design optimizations, Type 6-C had provided the best results in this study. The overall shape optimization studies on the shape, location, number, and so on, of the outlet holes, should be carried out further.
groups used in the present study. At 8 and 16 weeks in the experimental group, the RDD was less than that of control group B and the difference was statistically significant for the corresponding time. Newly-formed bone incorporated in the BCP particles were found in areas relatively close to the base and lateral walls of the defect in the 8-week experimental group. Newly-formed bone incorporated with BCP particles was found not only in relatively close areas, but also in areas relatively distant from the base and lateral wall of the defect at 16-weeks in the experimental group. This finding demonstrates that defect resolution was in progress between weeks 8 and 16. Apical migration of epithelium and loose connective tissue was less advanced in the experimental group than in control group B. This finding suggests that the space required for bone ingrowth was properly maintained by the bonesubstitute. New bone incorporated with bonesubstitute particles was found on the implant surface (Fig. 5B). Davies (1998) proposed that there are two different osteogenesis phenomena around dental implants: distance and contact osteogenesis.
A previous study was performed, in which CBCP loaded with 0.1 mg/mL rhBMP-2 was grafted into rabbit sinus, and significantly larger volumes of augmented and newly formed bone were found in the experimental group than the control group 4 weeks later . It was speculated that the postoperative swelling induced by rhBMP-2 resulted in a larger initial augmented volume, which was subsequently replaced by accelerated bone formation. Such early corticalization of the area surrounding the SM can resist the positive respiratory pressure, thereby reducing volumetric shrinkage. To further explore this line of research, the present study evaluated implant placement with simultaneous sinus augmentation. Although the same rhBMP-2 concentration and dosage were applied in the present study, the differences in volume appeared to be smaller than in the previous study.
골유도재생술 후 임프란트를 식립할 시점의 주변골은 미성숙 woven bone인 경우가 대부분이며 시간이 경과 하면서 성숙된 lamellar bone으로 변할 것이다. 이 상 황에서 부적절한 보철적 부하가 가해지거나 환자의 강 력한 저작 혹은 이갈이와 같은 구강악습관이 관여되면 보철 치료 중 혹은 보철 기능 초기에 변연골 흡수가 진 행되면서 초기 골유착이 파괴되어 임프란트 실패로 이 어질 가능성이 있다. 일부 학자들은 기능에 부합될 정도 의 성숙한 골이 형성되기 위해서는 하악 6개월, 상악 9 개월 이상이 필요하다고 언급하였다 18,19) . 이에 대한 처치 법에 대해 여러 학자들이 다양한 견해를 갖고 있으며 2006년 추계 구강악안면임프란트학회 학술심포지움에 서 5명의 연자들이 공통적으로 피력한 의견은 치유기간
Purpose: This retrospective study compares the amount of bone resorption around implants between an autogenous tooth bone graft (AutoBT) and a synthetic bone graft after a bone- added crestally approached sinus lift with simultaneous implant placements.
Methods: In all, 37 patients participated in this study. Seventeen patients were grouped as group I and underwent an AutoBT-added sinus lift using the crestal approach. The remaining 20 patients were grouped as group II and underwent synthetic bone grafting. Both groups received the implant placements simultaneously. Of the 37 participating patients, only 22 patients were included in the final results: Eleven patients of group I and 11 patients of group II. Before the surgery, the distance from the alveolar crest to the sinus floor was mea- sured using panoramic radiography. After the surgery, the distance was measured again from the neck of the implant thread to the most superior border of the added graft materials.
(Received January 20, 1964)
Byung Hoon Han; Metabolic fate of chloramphenicol-ester
Present experiment in vivo shows that some conversions of active groups in chloramphenicol residue of ester, that is hydrolytic cleavage of dichloracetamide and glucuronide formation, seem to take place prior to hydrolysis. This result suggest that the enzymatic hydrolysis rate in vitro, is not available as an index for the evaluation of the chloramphenicol ester potency.
해 이식에 필요한 이식재의 양을 감소시킬 수 있다는 결과를 얻었다.
본 연구에서도 bone patch를 이용하여 골유도재 생술의 효율을 증진시키고자 하였다.골 결손부에 골 이식재를 적용하고 그 상방에 흡수성 차단막을 피개하 는 두 단계에 걸친 기존의 골유도재생술 과정이, bone patch를 이용함으로써 한 단계로 간소화됨에 따라 결과적으로 골유도재생술에 소요된 시간이 유의 하게 감소한 것을 알 수 있었다. 특히, pin고정을 동 반한 군에 비해서는 절반 이상 감소한 평균 술식 시간 을 관찰할 수 있었다. 블록형 골 이식재와 흡수성 차단 막 사이의 접착은 이식재와 차단막의 위치 안정성을 증대시켰고, 이는 GBR군에서 관찰된 잔존 골 이식재 의 하방 분산 양상이 bone patch군에서는 관찰되지 않은 결과를 낳았다. 위치 안정성 증대 효과를 얻기 위 한 또 다른 방법이자 현재 임상에서 흔히 이용되는 pin 고정 방식이 복잡한 술식 과정을 동반하고 술식 시간을 증가시킨다는 문제점이 있다는 것으로 고려하 였을 때, bone patch의 이용은 술식 시간 감소와 이 식재의 위치 안정성 측면에서 pin고정방식을 대신할 수 있는 효과적인 방법이라고 평가할 수 있다. 다만, bone patch군 중 한 마리의 실험 동물에서 수술 후 bone patch의 블록형 골 이식재와 흡수성 차단막 사 이의 분리가 나타나면서 봉합 부위 열개가 발생하였는 데, 이는 bone patch의 블록형 골 이식재와 흡수성 차단막 사이의 접착 실패가 이식재료들의 위치 안정성 에 영향을 주어 발생한 합병증이었던 것으로 판단된 다. bone patch를 이용한 GBR이 pin 고정을 동반 하지 않는 만큼 흡수성 차단막과 골 이식재의 위치 안 정성 유지하기 위해 두 재료 간의 접착 강도를 증진시 킬 수 있는 연구가 이어져야 할 것이다.
changes which occur after the menopause .
The morphology and the variations of the craniofacial bones have been studied since the beginning of the century . The morphometric data of the styloid process is im- portant to the neurologists, neurosurgeons, radiologists and otorhinolaryngologists. The data on the interstyloid dis- tance is clinically important as this space accommodates im portant structures of neck like cranial nerves, larynx, eso- phagus, arteries, and veins. The surgical anatomy of the elon- gated styloid process is important to the neurosurgeons and radiologists while interpreting the computed tomogram scans and magnetic resonance images. The morphological know- ledge of Eagle’s syndrome is enlightening to all the health care professionals who are involved in the diagnosis and mana gement of chronic head and neck pain. The knowledge is important to the physicians, dentists, neurologists, neuro- surgeons, and otorhinolaryngologists. In this context, the present study has provided important data about the stylo- id process of the temporal bone. The dimensions of the styloid process andits stylohyoid chain are essential to the anatomists, anthropologists, forensic experts and clinicians.