Biomechanical Investigation of the Osseointegration of Titanium Implants With Different Surfaces Placed With Allogeneic Bone Transfer.

Allogeneic grafts can be preferred to autogenous grafts in plastic and oral-maxillofacial surgery for vertical and horizontal bone deficiencies. Implant surface properties are an important factor in osseointegration. This study aims to evaluate the osseointegration levels of titanium implants with machined, sand-blasted, and acid-etched (SLA) and resorbable blast material (RBM) surfaces placed together with allogeneic bone tissue transplantations obtained from the tibia bone using biomechanical method. Twenty-five female Sprague-Dawley rats were included in the study. The rats were divided into groups in which machined (n=7), SLA (n=7), and RBM (n=7) surface implants were placed with the transplantation of bone taken from the tibia. Four rats (both left and right tibias) were used as donors. Grafts and implants were surgically placed in the corticocancellous part of the metaphyseal area of the tibia bones of rats. At the end of the 4-week experimental setup, all rats were killed, and the implants and surrounding bone tissue were subjected to biomechanical reverse torque analysis (N/cm). Sand-blasted acid-etched surface implants were observed to have higher biomechanical osseointegration levels than RBM and machined surface implants (P<0.05). No statistical difference could be detected between the RBM and machined surface implants (P>0.05). On the basis of the limited results of this study, it can be concluded that the osseointegration levels of SLA surface implants placed with allogeneic bone transplantation may be better than those of machined and RBM surface implants.

Evaluation of the Effects of Dual Antiplatelet Therapy on Guided Bone Regeneration in Peri-Implant Bone Defect.

In this study, the authors aim to investigate the effect of dual antiplatelet agents on peri-implant-guided bone regeneraation by studying a sample of rats with titanium implants in their tibias. The rats were randomly divided into 5 groups: acetylsalicylic acid (ASA) (n=10), treated with 20 mg/kg of ASA; ASA+CLPD (Clopidogrel): (n=10), treated with 20 mg/kg of ASA and 30 mg/kg of clopidogrel; ASA+PRSG (Prasugrel): (n=10), treated with 20 mg/kg of ASA and 15 mg/kg of prasugrel; ASA+TCGR (Ticagrelor): (n=10), treated with 20 mg/kg of ASA and 300 mg/kg of ticagrelor; and a control group (n=10) received no further treatment after implant surgery. Bone defects created half of the implant length circumferencial after implant insertion and defects filled with bone grafts. After 8 weeks experimental period, the rats sacrified and implants with surrounding bone tissues were collected to histologic analysis; bone filling ratios of defects (%) and blood samples collected to biochemical analysis (urea, creatinine, aspartate aminotransferase, alanine aminotransferase, phosphorus, magnesium, alkaline phosphatase, calcium, and parathormone). A statistically significant difference was not detected between the groups for all parameters ( P >0.05). When the percentage of new bone formation was examined, it was found that there was no statistically significant difference between the groups ( P >0.05). Antiplatelet therapy may not adversely affect guided bone regeneration in peri-implant bone defects.

Osseointegration Levels of Implants Placed With Allogenic and Xenogenic Bone Ring: An Experimental Biomechanical Analysis.

This in vivo study aimed to do a biomechanical analysis of the early period bone-implant connection of titanium implants simultaneously inserted with xsenogenic and allogenic bone ring. In this study, 28 Sprague Dawley female rats were used. Four rats were killed to obtain an allogenic bone ring, and after this, the remaining rats were divided into control (n=8), xsenogenic (n=8), and allogenic (n=8) bone ring groups. Titanium-machined surfaced implants were integrated right tibias of the rats. In controls, only implants were integrated into right tibias. In the greft groups, the implants were integrated simultaneously with bone rings. After 2 weeks of the experimental period, the rats were killed ,and titanium implants and surrounding bone tissues were removed for biomechanic analysis. After biomechanical reverse torque analysis bone-implant connection was determined as Newton/cm 2 ; in controls 3.26 (1.2 to 4.5), in allogenic ring group 3.37 (2 to 4.4), in xsenogenic ring group 5.93 (2.8 to 10). Statistically significant differences were not detected between the groups ( P >0.05). Within the limitation of this study, both allogenic and xsenogenic bone grafts could be successfully used in bone augmentation in implant surgery.

Evaluation of the Effects of Systemic Irisin Application on Guided Bone Regeneration in Peri-implant Bone Defects.

This study aimed to investigate the effects of systemic irisin hormone application on new bone formation in peri-implant bone defects. After surgically creating peri-implant bone defects in the metaphyseal part of the tibiae of rats, the rats were randomly divided into 2 equal groups: a control group and an irisin group. In the control group, the rats received no further treatment during the 4-week experimental period after the surgery. The rats in the irisin group, 100 ng/kg irisin was administered intraperitoneally 3 days a week during the 8 weeks experimental period after the surgery. At the end of the experimental period, the rats were euthanized. Implants and surrounding bone tissues were collected for histological new bone formation analysis. The Student t test was used for statistical analysis. There were no significant differences between the groups in the histological analysis, new bone formation and fibrosis (P>0.05). Also, in the irisin group, there was numerically but not statistically more new bone formation detected compared with the controls. Within the limitations of this study, irisin did not affect new bone formation in peri-implant defects, although the numerical values favored the irisin group.

Effect of Primary Stabilisation on Osseointegration of Implants With Local and Systemic Zoledronic Acid Application.

ABSTRACT: Primary stabilization (PS) is defined as initial tight fit during the surgical placement of an implant. Tight implant placement is quite difficult in cases where bone quality and quantity are insufficient. Zoledronic acid (ZA) is a powerful bisphosphonate that prevents bone resorption. The aim of this study is to investigate the effect of local and systemic ZA application on osseointegration in titanium implants with and without PS. Male Sprague Dawley rats were divided into 2 main groups, with PS, PS + (n = 24), and without primary stabilisation, PS - (n = 24). These main groups were divided into control (n = 8), 2mg/1 mL local ZA (n = 8) and 0.1mg/kg systemic ZA (n = 8) groups. All of the subjects were sacrificed after a 4-week recovery period. Bone implant connection (BiC) and thread filling (TF) (%) of the samples was analyzed according to the non-decalcified histological analysis method. In terms of BiC percentages and TF, statistically significant differences were found between the groups with and without PS and between the ZA treatment groups ( P < 0.05). The common effect of PS and ZA use on the percentage of BIC was found to be statistically significant ( P < 0.05). The common effect of PS and acid type on TF was not statistically significant ( P < 0.05). Within the limitations of this study, it may be concluded that systemic and local administration of ZA may increase implant osseointegration.

Evaluation of the Effects of Topical Application of Chlorhexidine, Ozone, and Metronidazole on Palatal Wound Healing: A Histopathological Study.

ABSTRACT: This study aimed to evaluate the effects of chlorhexidine, metronidazole, and ozone application on the healing of palatal wounds in diabetic rats. A defect in the form of a 4 mm-diameter wound was created on the palatal mucosa of 84 adult female Wistar albino rats, which were randomly divided into 4 groups: control, chlorhexidine, metronidazole, and ozone groups. The animals were euthanized after 3, 6, and 10 days, and wound closure was histologically assessed. On day 3, polymorphonuclear leukocytes were significantly higher in the control group than in the chlorhexidine and ozone groups ( P < 0.05). Fibrosis was higher in the ozone group than in the control and chlorhexidine groups ( P < 0.05). Vascular endothelial growth factor was higher in the metronidazole and ozone groups than in the control group ( P < 0.05). On day 6, the quantity of polymorphonuclear leukocytes was higher in the control, metronidazole, and chlorhexidine groups than in the ozone group ( P < 0.05). Vascular endothelial growth factor was higher in the ozone group than in the control, chlorhexidine, and metronidazole groups ( P < 0.05). On day 10, Vascular endothelial growth factor was higher in the control, chlorhexidine, and metronidazole groups than in the ozone group ( P < 0.05). The authors concluded that the use of chlorhexidine, ozone, and metronidazole pastes resulted in enhanced wound healing, as determined histologically.The authors suggest that ozone supplementation can be an alternative therapy to chlorhexidine in impaired wound healing in diabetes mellitus.

Autogenous Tooth Bone Graft and Simvastatin Combination Effect on Bone Healing.

OBJECTIVE: Autogenous tooth bone grafts (ATGM) are materials prepared from extracted teeth and have been used for bone augmentation. These graft materials are known to have similar structures and components to bone grafts. In this sense, this study aimed to evaluate all the tooth layers mixed with simvastatin without any demineralization process effect on bone formation. METHODS: In 60 Wistar albino rats, a standardized 6.0 m-diameter critical size bone defect was created in their calvarium. The study consists of 1 control and 4 experimental groups. In the control group (12 rats), the defects were left empty. The defects were grafted only with ATGM in Group 1, with ATGM mixed with simvastatin in Group 2, autogenous bone graft mixed with simvastatin in Group 3, and with xenogenic bone graft mixed with simvastatin in Group 4. The animals were sacrificed at the 7th and 28th days after operation. RESULTS: PCR, micro CT and histological results show that bone formation was enhanced in the experimental groups in comparison to the control group. Group 1 and Group 2 had similar bone formation rate when compared to Group 3 and Group 4 at the 28th day after operation. CONCLUSION: This study concludes that mineralized teeth may be used for defect reconstruction without any demineralization process. Autogenous mineralized tooth bone graft should be mixed with simvastatin for bone regeneration like other grafts.

Comparison of Osseointegration of Five Different Surfaced Titanium Implants.

The topography, chemical features, surface charge, and hydrophilic nature of titanium implant surfaces are crucial factors for successful osseointegration. This study aimed to investigate the bone implant contact (BIC) ratio of titanium dental implants with different surface modification techniques using the rat femoral bone model. Sandblasted and acid washed (SL-AW), sandblasted (SL), resorbable blast material (RBM), microarc (MA), and sandblasted and microarc (SL-MA) surfaces were compared in this study. Forty male Sprague-Dawley rats were used in this study. The rats were divided into 5 equal groups (n = 8), and totally 40 implants were integrated into the right femoral bones of the rats. The rats were sacrificed 12 weeks after the surgical integration of the implants. The implant surface-bone tissue interaction was directly observed by a light microscope, and BIC ratios were measured after the nondecalcified histological procedures. Bone implant contact ratios were determined as follows: SL-AW: 59.26 ±â€Š14.36%, SL: 66.01 ±â€Š9.63%, RBM: 63.53 ±â€Š11.23%, MA: 65.51 ±â€Š10.3%, and SL-MA: 68.62 ±â€Š6.6%. No statistically significant differences were found among the 5 different surfaced titanium implant groups (P > 0.05). Our results show that various implant surface modification techniques can provide favorable bone responses to the BIC of dental implants.

Displacement of Dental Implant Into the Submental Space After Surgical Integration.

Osseointegrated dental implants are common and widely used to treat edentulism. Implant displacement into the maxillofacial spaces during surgery or after a period of use is a complication recognized in the literature. Foreign objects such as titanium dental implants in the maxillofacial region must be removed because they cause infection due to tissue reaction. In this report, the authors present the case of a patient whose dental implant slipped into the submental space after surgical integration and describe the surgical removal of the implant via an extraoral approach.

Comparison of the Effects of Local and Systemic Zoledronic Acid Application on Mandibular Distraction Osteogenesis.

Bisphosphonates are antibone resorptive drugs that are used to prevent bone tissue resorption in several skeletal diseases. The aim of this study was to examine the effects of systemic and local applications of zoledronic acid (ZA) on newly regenerated bone in a model of experimental distraction osteogenesis (DO). To do this mandibular DO was applied to 30 adult female Sprague Dawley rats, which were randomly divided into 3 groups: control, DO only, systemic zoledronic acid (SZA), and local zoledronic acid (LZA). In the LZA group, the gap between the bone fragments was filled with a gelatin sponge soaked in 2 mg of ZA and 0.1 mL of sterile saline. In the SZA group, a single dose of 0.1 mg/kg ZA was administered systemically. After the surgery, there was a 5-day latent waiting period and 10-day distraction phase. Following a 28-day consolidation period, the rats were euthanized and their mandibles were collected. The distracted bone area was seen to be filled with newly regenerated bone tissue in all 3 groups, both histologically and histomorphometrically. In addition, amounts of new bone formation, osteoblast cella, osteoclast (OC) cells, osteopontin, and vascular endothelial growth factor in the SZA and LZA groups were found to be higher when compared with the controls. Furthermore, in the SZA group, new bone formation, osteoblast, OC, osteopontin, and vascular endothelial growth factor were detected in significant amounts compared with the LZA group. Osteoclast numbers did not differ in a statistically significant manner in the SZA group with respect to the LZA group. Based on the results of this study, systemic and local applications of ZA could increase the formation of new bone in patients of DO, and systemic application is a more effective method compared with local application.

Effects of Local and Systemic Zoledronic Acid Application on Titanium Implant Osseointegration: An Experimental Study Conducted on Two Surface Types.

The aim of this study was to evaluate the effects of local and systemic zoledronic acid (ZA) applications on titaniumoksit ceramic blasted (TiO-CB)- and sandblasted large acid-grit (SLA)-surfaced titanium implant osseointegration. Twelve New Zealand White rabbits were used in the study, divided into 6 groups: the TiO-CB (TiO-CB-CNT) (n = 2) and SLA (SLA-CNT) (n = 2) control groups in which TiO-CB- and SLA-surfaced titanium implants were surgically inserted into rabbit tibias but no treatment was applied; the TiO-CB (TiO-CB-LZA) (n = 2) and SLA (SLA-LZA) (n = 2) local ZA groups in which 1 mL of normal saline solution containing 2 mg of ZA was injected into sockets and after this the implants were integrated; and the TiO-CB (TiO-CB-SZA) (n = 2) and SLA (SLA-SZA) (n = 2) systemic ZA groups in which a single infusion of 0.1 mg/kg of ZA was administered during surgical implant insertion. Following a period of osseointegration, bone implant contact (BIC) was recorded as a proportion of the total implant surface length in direct contact with the bone. Results of this study indicate that BIC was greater in the systemic ZA application groups than in the local ZA application groups, and BIC was greater in the local ZA groups than in the controls. Statistically significant differences in BIC were not detected between the TiO-CB- and SLA-surfaced implants in all the groups. Furthermore, this study did not reveal significant differences between the 2 types of surfaces due to similar average roughness values. Overall, systemic ZA application was found to be more effective in increasing BIC than local ZA application based on the results obtained by testing 2 implant surfaces.

Treatment of Class II malocclusion with mandibular skeletal anchorage.

INTRODUCTION: The aim of this case report was to present the dentofacial changes obtained with bone anchorage in a Class II patient with moderate to severe crowding. METHODS: A boy, aged 14.5 years, with a dolichofacial type, convex profile, and skeletal and dental Class II relationships was examined. After evaluation, functional treatment with bone anchorage and 4 first premolar extractions was decided as the treatment approach. Miniplates were placed on the buccal shelves of the mandibular third molars. The hook of the anchor was revealed from the first molar level. After surgery, the 4 first premolars were extracted to retract the protrusive mandibular incisors. The maxillary and mandibular first molars were banded, and a lip bumper was inserted to apply elastics and to help distalize the maxillary first molars. Orthodontic forces of 300 to 500 g were applied immediately after placement, originating from the miniscrews to the hooks of the appliance to advance the mandible. RESULTS: After 20 months of treatment, the patient had a dental and skeletal Class I relationship, the mandible was advanced, the maxilla was restrained, and overjet was decreased. CONCLUSIONS: The combination of a bone anchor, Class II elastics, and an inner bow is a promising alternative to functional treatment, along with extractions, in Class II patients.

Effects of the Application Local Zoledronic Acid On Different Dental Implants in Rats On Osseointegration.

Objective: Recently, a lot of research has been done around the world to popularize the osseointegration of dental implants. In this study, it was investigated the effect of local zoledronic acid application on implants with machined (MAC), resorbable blast materials (RBM), sandblasted and acid-etched (SLA) surface implants integrated in rat tibias. Methodology: A total of 60 female Wistar rats weighing between 270 and 300 g were used in the study. The rats were passing divided into six classes: controls; MAC (n = 10), RBM (n = 10), SLA (n = 10), and local zoledronic acid (LZA) applied groups; LZA-MAC (n = 10), LZA-RBM (n=10) and LZA-SLA (n = 10) and implants were surgically placement into rat tibias in general anesthesia. After a four-week experimental period, the biomechanical bone implant connection level was determined with reverse torque analysis. Results: Osseointegration levels were detected highly in SLA and RBM surface compared with the machined surfaced implants in both control and treatment groups (p < 0.05). Additionally, local application of zoledronic acid in both three groups; implants increased the biomechanic osseointegration level compared with the controls (p < 0.05). Conclusion: In this research, we observe that the local application of the zoledronic acid could increase the osseointegration, and RBM and SLA surface could be better than machined surfaced implants in terms of bone implant connection. In addition, local application of zoledronic acid may be a safer method than systemic application.

An evaluation of factors associated with persistent primary teeth.

The aim of the present study was to investigate the reasons for the persistence of primary teeth and also use panoramic radiography to determine the characteristics of persistence teeth. Four-hundred and twenty-six panoramic radiographies, which diagnosed one or more retained primary teeth, were selected from 100,577 panoramic radiographic image files from nine clinics and six different cities in Turkey. The selected radiographies were evaluated to determine the reasons for the persistence of primary teeth; furthermore, this study analyzed the characteristics of the retained primary teeth including tooth type, number, location, and root resorption, and whether, or not, the primary teeth showed evidence of pathological conditions, such as periodontal problems, caries, ankylosis, infra-occlusions, or tipping of the adjacent permanent teeth. Six hundred and seventy-seven retained primary teeth were determined in 426 patients (148 males and 278 females). Retained primary teeth were found most frequently in the mandible rather than the maxilla and the left side was more frequently affected than the right side. Level 1 was found as a most frequently encountered root resorption level. Within the limitation of the present study, the most common type of persistent primary teeth seen on the dental arch were mandibular primary second molars, followed by maxillary primary canines. The most frequent reason for the persistence was the congenital absence of successors to the primary teeth, followed by impaction of the successor teeth.

Effects of restraint stress and high-fat diet on osseointegration of titanium implants: an experimental study.

This study aimed to investigate the effects of chronic restraint stress (RS) and a high-fat diet (HFD) on the osseointegration of titanium implants in a rat model. After the surgical insertion of titanium implants into the metaphysis of the tibial bone, the rats were randomly divided into four equal groups (n = 8 each): control (CNT), restraint stress (RS), high-fat diet (HFD), and restraint stress plus high fat diet (RS-HFD). CNT: Rats received no further treatment during the 92-day experimental period. RS: Stress was applied to the rats beginning from two days after the implant surgery for one hour per day for the first 30 days, two hours per day for the next 30 days, and three hours per day for the last 30 days. HFD: Rats were fed a HFD for the following 90 days starting two days after surgery. RS-HFD: Rats were fed a HFD and RS was applied to rats for the following 90 days, starting two days after surgery. At the end of the experimental period, the rats were euthanized, and the implants and surrounding bone tissues were removed for histological analysis. Statistical analysis was performed by one way ANOVA and Bonferrroni tests. There were no significant differences in the bone-implant connection levels between the groups (p > 0.05), but in the HFD and RS-HFD groups, the bone filling ratios were found to be lower compared with the controls (p < 0.05) The data analyzed in this study suggest that an HFD with or without chronic RS adversely affected bone tissue in the rats during the 90-day osseointegration period.

An experimental investigation of the effects of chronic stress on bone-to-implant contact.

OBJECTIVES: This study aimed to investigate the effects of chronic restraint stress on the osseointegration of titanium implants. MATERIALS AND METHODS: Twenty adult male Wistar albino rats were used in the study. After surgical insertion of titanium implants into the metaphyseal part of the tibial bone, rats were randomly divided into two groups: a control group (CNT group) and an experimental restraint stress group (RS group). In the CNT group, titanium implants were inserted surgically, and rats received no further treatment during the 47-day experimental period. In the RS group, restraint stress was applied for 3 hours per day for 45 days, beginning 2 days after implant surgery. Weight of the rats was measured prior to surgery and at the end of the study to analyze the effects of stress. At the end of the experimental period, rats were euthanized, and implants and surrounding bone tissues were used for undecalcified histological analysis. Serum cortisol levels were assessed in cardiac blood samples from the rats following centrifugation. RESULTS: Average weight of rats in the RS group was lower than that of rats in the CNT group after the experimental protocol had been completed (P<0.05). Further, serum cortisol levels were higher in the RS group than in the CNT group (P<0.05). There were no significant differences in bone-implant connection levels between the two groups (P>0.05). CONCLUSION: The data analyzed in this study suggest that chronic restraint stress did not adversely affect rats during a 45-day osseointegration period.

Systemic melatonin application increases bone formation in mandibular distraction osteogenesis.

This study aimed to investigate the effects of different doses of systemic melatonin application on new bone formation during mandibular distraction osteogenesis (DO) in rats. Mandibular DO was performed on 30 adult female Sprague-Dawley rats, which were randomly divided into three groups: control group (CNT), melatonin dose 1 (MLT-D1), and melatonin dose 2 (MLT-D2). A five-day latent waiting period and a ten-day distraction phase followed the surgery. After the surgery, rats from the MLT-D1 and MLT-D2 groups received 25 and 50 mg/kg melatonin, respectively, at 7, 14, 21, 28, and 35 days. The animals were euthanised 28 days after distraction, i.e. at 43 days after surgery. Histological and histomorphometric analyses revealed that the distracted bone area was completely filled with new bone formation in all three groups. The MLT-D2 group exhibited the most new bone formation, followed by MLT-D1 and CNT. The melatonin groups had more osteoclasts than the CNT (p < 0.05). The number of osteoblasts was higher in the melatonin groups than in the CNT group, and the MLT-D2 had more osteoclasts than the MLT-D1 group (p < 0.05). Finally, the osteopontin (OPN) and vascular endothelial growth factor (VEGF) levels were higher in the melatonin groups than in the CNT group, and the MLT-D2 had higher OPN and VEGF levels than the MLT-D1 (p < 0.05). This study suggests that systemic melatonin application could increase new bone formation in DO.

A comparison of different bone graft materials in peri-implant guided bone regeneration.

The aim of this study was to compare the effects of hydroxyapatite (HA), deproteinized bovine bone (DPB), human-derived allogenic bone (HALG), and calcium sulfate (CAP) graft biomaterials used with titanium barriers for bone augmentation to treat peri-implant defects in rat calvarium treated by guided bone regeneration (GBR). Thirty-two female Sprague-Dawley rats were divided into four groups: DPB, HALG, HA, and CAP. One titanium barrier was fixed to each rat's calvarium after the titanium implants had been fixed. In total, 32 titanium implants and barriers were used. Ninety days after the surgical procedure, all the barriers were removed. After decalcification of bone tissue, the titanium implants were removed gently, and new bone regeneration in the peri-implant area was analyzed histologically. Immunohistochemical staining of vascular endothelial growth factor (VEGF) was also performed. There were no statistically significant between-group differences in new bone regeneration or VEGF expression after 3 months. According to the results of the histological and immunohistochemical analyses, none of the grafts used in this study showed superiority with respect to new bone formation.

The effects of high-fat diet on implant osseointegration: an experimental study.

OBJECTIVES: In this study, we investigated whether a high-fat diet (HFD) affected the bone implant connection (BIC) in peri-implant bone. MATERIALS AND METHODS: Four male rabbits were used in this study. Dental implant surgery was introduced into each tibia, and four implants were integrated into each animal. In both the normal diet (ND) group (n=2) and HFD group (n=2), 8 implants were integrated, for a total of 16 integrated implants. The animals continued with their respective diets for 12 weeks post-surgery. Afterward, the rabbits were sacrificed, and the BIC was assessed histomorphometrically. RESULTS: Histologic and histomorphometric analyses demonstrated that BIC was not impaired in the HFD group compared to the ND group. CONCLUSION: Within the limitations of this study, we found that HFD did not decrease the BIC in rabbit tibias.

Dental stem cell sources and their potentials for bone tissue engineering.

Tissue engineering arouses excitement in all medical fields that deal with bone healing. The ultimate aim of these approaches are to shorten the healing process, obtain highly differentiated functional tissues and eliminate the need for a second surgical site required for autogenous bone grafts. Mesenchymal stem cells have been increasingly used in the experiments which were conducted in these fields and the results are promising. Dental stem cells have come to the forefront both because of their relative ease of access and also their superior characteristics. This article investigates the importance of dental stem cells for bone tissue engineering and their regeneration potentials.