Bone Cements ; Calcium ; Calcium Phosphates ; Materials Testing

Humans ; Bone Cements/adverse effects* ; Paralysis/etiology*

PURPOSE: Implant beds with an insufficient amount of cortical bone or a loss of cortical bone can result in the initial instability of a dental implant. Thus, the objective of this study was to evaluate the effect of bone cement grafting on implant initial stability in areas with insufficient cortical bone. METHODS: Two different circumferential defect depths (2.5 mm and 5 mm) and a control (no defect) were prepared in six bovine rib bones. Fourteen implants of the same type and size (4 mm x 10 mm) were placed in each group. The thickness of the cortical bone was measured for each defect. After the implant stability quotient (ISQ) values were measured three times in four different directions, bone cement was grafted to increase the primary stability of the otherwise unstable implant. After grafting, the ISQ values were measured again. RESULTS: As defect depth increased, the ISQ value decreased. In the controls, the ISQ value was 85.45+/-3.36 (mean+/-standard deviation). In circumferential 2.5-mm and 5-mm defect groups, the ISQ values were 69.42+/-7.06 and 57.43+/-6.87, respectively, before grafting. These three values were significantly different (P<0.001). After grafting the bone cement, the ISQ values significantly increased to 73.72+/-8.00 and 67.88+/-10.09 in the 2.5-mm and 5.0-mm defect groups, respectively (P<0.05 and P<0.001). The ISQ value increased to more than double that before grafting in the circumferential 5-mm defect group. The ISQ values did not significantly differ when measured in any of the four directions. CONCLUSIONS: The use of bone cement remarkably increased the stability of the implant that otherwise had an insufficient level of stability at placement, which was caused by insufficient cortical bone volume.
Alveolar Bone Loss ; Bone Cements ; Dental Implants ; Ribs ; Transplants*

OBJECTIVETo explore the possibility of repairing periodontal defects with carbonated calcium phosphate bone cement (CCPBC) modified with synthesized peptides.

METHODSPeriodontal bone defects in 4 dogs were surgically created and then restored directly with hydroxyapatite (HA), Perioglass, CCPBC and CCPBC modified with peptides. The results were compared at different levels.

RESULTSBone replacement materials were lost in HA and Perioglass groups. In the HA group defects were restored with connective tissue. Perioglass group had only a little new bone around materials by alveolar bone. CCPBC could firmly stay in bone defects to maintain the space of bone defects even without membrane use. CCPBC modified with peptides was superior to HA, Perioglass, and CCPBC, surrounded by a great deal of new bone.

CONCLUSIONUnder limitation of this study, CCPBC modified with peptides has some osteoinuctive activity and may have good prospect for the clinical application in periodontal defect repair.

Alveolar Bone Loss ; therapy ; Animals ; Bone Cements ; Bone Regeneration ; Bone Substitutes ; Calcium Phosphates ; Dogs ; Durapatite ; Male

OBJECTIVE: The purpose of this study is to find the optimal stiffness and volume of bone cement and their biomechanical effects on the adjacent vertebrae to determine a better strategy for conducting vertebroplasty. METHODS: A three-dimensional finite-element model of a functional spinal unit was developed using computed tomography scans of a normal motion segment, comprising the T11, T12 and L1 vertebrae. Volumes of bone cement, with appropriate mechanical properties, were inserted into the trabecular core of the T12 vertebra. Parametric studies were done by varying the volume and stiffness of the bone cement. RESULTS: When the bone cement filling volume reached 30% of the volume of a vertebral body, the level of stiffness was restored to that of normal bone, and when higher bone cement exceeded 30% of the volume, the result was stiffness in excess of that of normal bone. When the bone cement volume was varied, local stress in the bony structures (cortical shell, trabecular bone and endplate) of each vertebra monotonically increased. Low-modulus bone cement has the effect of reducing strain in the augmented body, but only in cases of relatively high volumes of bone cement (>50%). Furthermore, varying the stiffness of bone cement has a negligible effect on the stress distribution of vertebral bodies. CONCLUSION: The volume of cement was considered to be the most important determinant in endplate fracture. Changing the stiffness of bone cement has a negligible effect on the stress distribution of vertebral bodies.
Bone Cements ; Finite Element Analysis ; Spine ; Sprains and Strains ; Vertebroplasty

BACKGROUNDDuring the process of bone cement joint replacement, some patients show a series of complications, such as a sudden drop in blood pressure or dyspnea. The cause of the complication is considered to be due to emboli caused by the femur prosthesis insertion. The purpose of the present study was to detect the pulmonary embolism in rabbits after bone cement perfusion by radioimmunoimaging, and to explore its protective measures.

METHODSForty rabbits, 2.5 - 3.0 kg weight, were randomly assigned to four groups, with ten rabbits in each group. Group I (no intervention): Bone cement perfusion was done after medullary cavity reaming and pressurizing. Group II (epinephrine hydrochloride intervention): The medullary cavity was rinsed with a 1:10 000 normal saline-diluted epinephrine hydrochloride solution followed by bone cement perfusion after medullary cavity reaming and pressurizing. Group III (fibrin sealant intervention): The medullary cavity was precoated with fibrin sealant followed by bone cement perfusion after medullary cavity reaming and pressurizing. Group IV (blank control group): The medullary cavity was not perfused with bone cement after reaming. In each group, the rabbits underwent femoral head resection and medullary cavity reaming. Before bone cement perfusion, 2 ml of developing tracer was injected through the ear vein. Radionuclide imaging was performed at 60, 120, and 180 minutes after bone cement perfusion, and the pulmonary radioactivity in vivo was measured. The rabbits were immediately sacrificed, and the pulmonary tissue was removed and its radioactivity was measured in vitro. Pulmonary tissue was then fixed and the pulmonary embolism and the associated pathological changes were observed.

RESULTSThe pulmonary radioactivity in vivo was measured at 60, 120, and 180 minutes after bone cement perfusion. The radioactivities of the four groups were 11.67 ± 2.16, 14.59 ± 2.92 and 18.43 ± 4.83 in group I; 8.37 ± 3.05, 10.35 ± 2.24 and 11.48 ± 2.96 in group II; 3.91 ± 1.19, 5.53 ± 2.95 and 7.25 ± 1.26 in group III; 1.04 ± 0.35, 1.14 ± 0.87 and 1.43 ± 0.97 in group IV. The radioactivities of groups I, II, III at 60, 120 and 180 minutes were significantly higher than group IV (P < 0.05). The pulmonary embolism could be detected. Pretreatment with epinephrine hydrochloride and fibrin sealant significantly decreased the pulmonary radioactivity in group II and group III, but it was still higher than in the group IV.

CONCLUSIONSRadioimmunoimaging is an alternative method for the dynamic observation of rabbit pulmonary embolism after bone cement perfusion. Radioimmunoimaging is the optional way to evaluate the effect of pretreatment with epinephrine hydrochloride or fibrin sealant on pulmonary embolism after bone cement perfusion.

Animals ; Bone Cements ; Pulmonary Embolism ; diagnosis ; Rabbits ; Radioimmunodetection ; methods

Calcium phosphate cement (CPC) is considered as an important bone repairing materials due to its excellent biocompatibility, osteoconductivity and remodellability, the study about its performance is still a hot topic in the field of bone tissue engineering. Premixed calcium phosphate cements (PCPC) has advantages that can save operatiion time,be convenient to the operation and preservation compared with the traditional way of immediately mixing calcium phosphate cement. PCCP has overcome the shortcomings of uneven and inadequate mixing, and can be arbitrarily remodeled according to the shape of defect, thus researches on PCCP has also become more and more interested
Bone Cements ; chemistry ; Calcium Phosphates ; chemistry ; Humans ; Materials Testing ; Solubility

PURPOSE: This paper reviewed the safety and effectiveness of anchor augmentation with bone cement in osteoporotic femoral fractures. MATERIALS AND METHODS: A systematic review was conducted by searching multiple databases including five Korean databases, Ovid-MEDLINE, Ovid-EMBASE, and Cochrane Library. Safety was assessed through the incidence of complication. The effectiveness was assessed through the failure rate of anchor fixation, improvement of function and radiological assessment (sliding distance of lag screw and cutout). The safety and effectiveness of anchor augmentation with bone cement were assessed by reviewing all articles reporting on the treatment. Two researchers carried out independently each stage from the literature search to data extraction. The tools of Scottish Intercollegiate Guidelines Networks were used to assess the quality of studies. RESULTS: Six studies were considered eligible. The safety results revealed a small amount of cement leakage (1 case), but no other severe complications were encountered. Regarding the effectiveness, the failure rate of anchor fixation was 16.7% and the Harris's hip score showed no significant improvement. The sliding distance of the anchor was similar in the cement augmentation group and non-cement group but there was no cutout. CONCLUSION: The results of the assessment suggest that the safety is acceptable, but further research will be needed to verify the effectiveness of the treatment.
Bone Cements ; Femoral Fractures ; Femur ; Hip ; Incidence ; Osteoporotic Fractures

Calcium phosphate cement (CPC) is well known for the excellent bioactivity and biocompatibility, however, CPC has been used only for the repair of non-load bearing bone defects due to its brittle nature and low flexural strength. Polymer reinforced CPC has been considered as one of the most effective strategies for mechanical reinforcement. This paper summarizes various kinds of polymers loaded CPC:fiber reinforcement, microsphere reinforcement and dual setting cements. It is aimed to analyze the advantages, disadvantages and principles of the polymers reinforced CPC, and so as to lay a foundation for the further research of improving and manufacturing the CPC with ideal mechanical properties.
Biocompatible Materials ; Bone Cements ; Calcium Phosphates ; Materials Testing ; Polymers

Bone Cements ; Femur ; pathology ; Humans ; Osteolysis, Essential ; therapy ; Syndrome