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Background: A close anatomic relationship between the incisive canal and the roots of the central maxillary incisors should be kept in mind during dental-implant treatment in the anterior maxilla. The aim of the present study is to analyze incisive canal characteristics on computed tomography (CT) sections and to evaluate its relation to bone anterior to the canal with regard to dental implantation. Methods: A total of 933 partially edentulous and/or edentulous patients scheduled for implant insertion in four dental clinics enrolled in the present study. The following were measured and recorded from CT sections for analysis: 1) diameter and length of the incisive canal; 2) width and length of the bone anterior to the canal; 3) palatal bone width and length; and 4) root width and length of the central incisor. Results: Mean canal length was 10.86 ± 2.67 mm, and mean diameter was 2.59 ± 0.91 mm. Canal length was shortened in edentulous anterior maxilla compared to dentate maxilla. However, canal diameter did not show any difference between dentate and edentulous groups. Males had a longer and wider incisive canal than females. Canal shape was mostly cylindrical in 40.73% of images. No correlation was found with mean canal length and mean canal diameter according to age. Conclusions: Although variations exist in every patient, the findings from this study suggest that sex and dental status are important factors that can affect incisive canal characteristics and amount of bone anterior to the canal. Clinicians should perform careful planning using CT scans before performing dental implant surgeries in premaxillary region. [ABSTRACT FROM AUTHOR]

Introduction: The American Association of Endodontics (AAE) Regenerative Endodontics Committee reports here the web-based survey data of regenerative endodontic procedures performed by the AAE members from 2008 to 2019., Methods: The web-based survey consisted of 2 questionnaires, a revascularization and a follow-up, including clinical and radiographic data at 3, 6, 12 or >12 months after treatment. Data from demographics, etiology, clinical protocols, radiographic, and clinical outcome as perceived by the clinicians were recorded. From 927 entries, 184 full cases were submitted and 126 were suitable for radiographic analysis. The data were divided into cases with 6-12 months and cases with >12 months recall time. Descriptive statistics and univariate analyses were performed., Results: Predominantly patients were male (63%), average 10 years-old with anterior teeth (77.2%) due to trauma (69.6%). A wide variation in regenerative endodontic procedures protocols was reported by the AAE members. The most common clinical protocols used minimal instrumentation (75.5%), 2.5% or higher concentrations of sodium hypochlorite (83.7%), and antibiotic paste as intracanal medication (58.7%). The majority reported blood clot formation (56%) and most common coronal capping material was white mineral trioxide aggregates (50.5%). Increases in radiographic root length, and radiographic root area were proportional to the time lapsed after treatment. Overall, case outcomes were categorized by clinicians as successful (54.3%), uncertain (23.9%), and unsuccessful (3.8%)., Conclusions: This web-based survey provides a valuable perspective on case selection, clinical protocols, and perceived outcomes for regenerative endodontic procedures and supports the need for future higher level evidence studies., (Copyright © 2024 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

This canine in vivo study assessed the effect of recombinant human platelet-derived growth factor (rhPDGF) on the healing of periapical tissues following apical surgery. From a total of 96 premolar teeth, 64 teeth from six beagle dogs (2 years old) were classified as experimental and were randomly assigned to four experimental groups (16 teeth per group). After having the pulp extirpated, leaving teeth open to the oral cavity for 1 week, and sealing with an immediate restorative material for 8 weeks, nonsurgical endodontic treatment was performed. A split-mouth design was used, and intra-animal randomization of treatment sides was applied to the groups as follows: apical curettage + 1.5-mm root-end resection (Group 1); apicoectomy + mineral trioxide aggregate (MTA) root-end filling (Group 2); apicoectomy + MTA root-end filling + rhPDGF (Group 3); and apical curettage + rhPDGF (Group 4). The animals were sacrificed 24 months after apical surgery, and histologic and μCT analyses were performed for bone volume loss (BVL). Group 1 showed partial resolution of the periapical lesions without signs of tissue regeneration (BVL: 49.09 ± 10.97 mm3). Group 2 had minimal bone regeneration and showed cementum reformation in 9 teeth, with no direct attachment to the MTA (BVL: 35.34 ± 10.97 mm3). Group 3 showed regeneration of all damaged apical tissues without direct contact between the cementum and MTA (BLV: 4.51 ± 1.55 mm3). Group 4 showed regeneration of PDL, bone, and cementum and attachment of functional cementum fibers (BVL: 2.82 ± 2.3 mm3). The difference in BVL was statistically significant only for Groups 1 and 2 (P < .05). rhPDGF may help regenerate apical tissue structures following apical surgery.

Introduction: Selective serotonin reuptake inhibitors (SSRIs) are commonly used to treat depression and anxiety. The purpose of this study was to assess in real time the effect of paroxetine, an SSRI, on newly formed bone volume (NFBV) in standardized calvarial defects (SCDs) in rats., Methods: Fourteen Wistar albino female rats with a mean age of 7.5 months and a mean weight of 275 g were used. The animals were randomly divided into 2 groups. The experimental group was given paroxetine 8 weeks before the surgical procedure and throughout the experiment, and the control group was given a placebo 8 weeks before the surgical procedure and throughout the experiment. In each group, 14 SCDs measuring 4.6 mm in diameter were created on the parietal bone. In both groups, a Bio-Oss + collagen membrane was placed. All defects showed primary closure. The volume of the newly formed bone (NFBV) was measured using in vivo micro-computed tomographic imaging. Measurements were taken at days 0, 14, 28, 42, and 56 after surgery using real-time assessment with micro-computed tomographic imaging., Results: The mean NFBV was 17.12 ± 4.52 mm 3 and 12.52 ± 4.78 mm 3 for the control and experimental groups, respectively, at day 56. The differences between the 2 groups were statistically significant (P < .05) at all time intervals., Conclusions: Paroxetine intake significantly reduced the amount of regenerated NFBV and the rate of new bone formation., (Copyright © 2023 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

A significant advancement in micro-computed tomography (μCT) translational application in endodontics has occurred. The purpose of the study was to assess the applications of a new method to measure dentin mineral density (DMD) and to compare between 2 levels of energy sources. Two sets of standardized porous solid hydroxyapatite (HA) phantoms, with mineral densities of 0.25 g/cm 3 and 0.75 g/cm3, respectively were embedded in aluminum foil. The μCT homogeneity and noise in the HA phantoms were analyzed using 50 kV and 100 kV energy sources. DMD of 66 extracted human teeth was measured at the cemento-enamel junction (CEJ), mid-root, and apical levels. Assessment included linearity between the energy source and the DMD measurement. The quality of the images obtained from the 2 energy sources was compared and analyzed statistically. HA phantom rods and validation methods showed that 100 kV provided a more accurate measurement of the DMD in all groups tested. The 100 kV 3D reconstructed µCT images displayed a more defined details of the dentin structure. A statistically significant difference was found between 100 and 50 kV (p < 0.05) in all measured areas except for the mid-root. Using micro-computed tomography is a practical and non-destructive method to measure dentin density. 100 kV energy source provides clearer and more consistent images., (© 2023. The Author(s).)

Buccal bone remodeling around immediate implants placed in animals with streptozotocin (STZ)-induced diabetes has not been investigated. The present histologic and microcomputed tomography (μCT) in vivo experiment assessed the buccal bone remodeling around immediate implants, extraction socket healing, and bone-to-implant contact (BIC) in dogs with and without STZ-induced diabetes. Three male beagle dogs with STZ-induced diabetes and three healthy dogs (controls) were included. Fasting blood glucose levels were measured using a glucometer. Under general anesthesia, all animals underwent atraumatic tooth extraction of bilateral maxillary and mandibular second premolar teeth using Piezosurgery and immediate implant placement in the distal root socket. Primary closure was achieved for all implants and adjacent socket sites. After 11 months, all animals were sacrificed, and buccal bone thickness (BBT), marginal bone loss (MBL), BIC, and mesial extraction socket bone volume were assessed in control and diabetic animals using histologic and μCT examination. High-resolution μCT analyses were performed to identify the percentage of osteocytes and blood vessels in bone specimens harvested from a mesial extraction socket in each group. BBT and BIC were significantly higher in control dogs (P < .05), and diabetic dogs demonstrated significantly more MBL than control dogs (P < .05). Compared to healthy subjects, the sockets of induced diabetic dogs lost over 50% of bone horizontally and vertically. Control group had more significant osteocytes (38.85%) and blood vessels (37.87%), whereas the same values for STZ-induced diabetic dogs were 27.92% and 27.76%, respectively. Buccal bone loss and MBL were significantly higher around immediate implants placed in dogs with STZ-induced diabetes and were associated with multiple implant buccal thread exposure. A large percentage of socket space in diabetic dogs healed with nonosseous structure following tooth extraction.

To evaluate the risk to public health from Flaviviruses in the southwest region of the Kingdom of Saudi Arabia, we screened as sentinels, 50 commensal hamadryas baboons located at a peri-domestic site on the outskirts of Ta'if City in February 2013. Of the baboons, 12% [95% CI 5, 24], 0% [95% CI 0, 7] and 10% [95% CI 3, 22] were seropositive in a pan-Flavivirus ELISA (anti-pan-WNV 1-2, Usutu, Zika), Dengue virus 1-4 ELISA (anti-DENV 1-4) and WNV-1 PRNT, respectively, indicating Flavirus exposures of the subjects with possible risk to public health in the area., (© 2021. EcoHealth Alliance.)

This in vivo study assessed calcium hydroxide's effect as a matrix carrier for recombinant human platelet-derived growth factor (rhPDGF) and enamel matrix protein (EMD) on pulp tissue healing following pulp capping. Intact premolar sites (n = 18) were included. Coronal access and pulpotomy were performed, and each tooth was exposed to the oral cavity for 1 hour before pulp capping was performed. Teeth were randomly assigned to one of the following pulp-capping groups (n = 6 each): Group 1 (CaOH 2 only); Group 2 (CaOH 2 +EMD); and Group 3 (CaOH 2 +rhPDGF). Coronal access cavities were then sealed. Immediate preoperative, postoperative, and 4-month follow-up radiographs were taken. At 4 months, teeth were extracted atraumatically and histomorphometric and micro-CT analyses were performed. Group 1 showed formation of thin, uneven, highly porous dentin-like structure with tunnel defects (average thickness: 0.18 to 0.19 mm). Lack of continuity of the newly formed tissue and interrupted communication tunnels were seen between the pulpal space and pulp-capping material. Group 2 showed formation of highly dense, nonporous, even-thickness dentin-like structure obliterating multiple areas of the pulp space (average thickness: 0.9 to 0.94 mm). Abundant odontoblast lacunae were present in the pulp and structure. Group 3 showed formation of an inconsistent, uneven dentin-like structure that appeared highly porous (average thickness: 1.04 to 1.05 mm). It was without tunneling, and abundant odontoblastic lacunae were present. No statistically significant differences were found between Groups 2 and 3, but both were richer in newly formed dentin-like structure with more thickness than Group 1 ( P < .05). Addition of EMD to CaOH 2 can result in multiple root canal calcifications, mostly in the coronal and apical thirds of the canals. The calcified tissue does not appear to resemble secondary dentin in form, shape, amount, or density. Addition of rhPDGF to CaOH 2 may not cause root canal calcifications. The newly formed structure differs from secondary dentin in degree of mineralization, porosity, and density.

This in vivo study assessed the effect of mineral trioxide aggregate (MTA) as a matrix carrier for recombinant human platelet-derived growth factor (rhPDGF) and enamel matrix protein (EMP) on pulp tissue healing following pulp capping. Eighteen intact human premolars scheduled for extraction were included. Coronal access and pulpotomy were performed, and each tooth was left exposed to the oral cavity for 1 hour before pulp capping was performed. Teeth were randomly assigned to one of the following pulp-capping groups (n = 6 each): Group 1 (MTA only); Group 2 (MTA+EMP); or Group 3 (MTA+rhPDGF). Coronal access cavities were then sealed. Immediate preoperative, postoperative, and 4-month follow-up radiographs were taken. At 4 months, the teeth were extracted atraumatically, and histomorphometric and micro-computed tomography (μCT) analyses were performed. Group 1 showed a thin, uneven, irregular dentin-like structure. Its average thickness was 0.3 ± 0.084 mm measured histologically and 0.29 ± 0.091 mm measured by μCT. Group 2 showed of a nonporous, even-thickness dentin-like structure with multiple root-canal obliterations. Highly dense, atubular dentin-like structures associated with presence of odontoblastic lacunae were seen. The structure's average thickness was 0.87 ± 0.09 mm (histologically) and 0.81 ± 0.17 mm (μCT). Group 3 showed a thick and complete 3D continuous seal of newly formed dentin-like structure covering the pulpal space. It resembled secondary dentin in form, porosity, and tubular structural organization, and its average thickness was 0.94 ± 0.02 mm (histologically) and 0.91 ± 0.09 mm (μCT). Groups 2 and 3 showed higher amounts of newly formed dentin-like structure, that was also thicker, than Group 1 ( P < .05). No statistically significant differences in structure thickness were found between Groups 2 and 3. The nature of the structure can differ if rhPDGF or EMP is added to MTA for pulp-capping purposes. Combination of rhPDGF and MTA resulted in a newly formed structure resembling secondary dentin, whereas a combination of EMP and MTA produced a nonporous, highly dense dentinal-like structure associated with significant root-canal obliterations.

Background and Objectives : Beta-tricalcium phosphate (beta-TCP) has been used for bone regeneration. The objective of this study was to assess longitudinally, the regeneration of critical sized segmental defects (CSSD) in rat femur using beta-TCP with or without recombinant platelet-derived growth factor (PDGF) through in vivo micro-computed tomography (micro-CT). Materials and Methods : Following ethical approval unilateral femoral CSSD measuring 5 mm was surgically created, under general anesthesia, in 30 male Wistar-Albino rats (aged 12-18 months; weighing 450-500 g). CSSD was stabilized using titanium mini-plate (4 holes, 1.0 mm thick with 8 mm bar). Depending upon biomaterial used for regeneration, the animals were randomly divided into: Control group ( N  = 10): CSSD covered with resorbable collagen membrane (RCM) only; Beta-TCP group ( N  = 10): CSSD filled with beta-TCP and covered by RCM; Beta-TCP + PDGF group ( N  = 10): CSSD filled with beta-TCP soaked in recombinant PDGF and covered by RCM. Longitudinal in vivo micro-CT analysis of the CSSD was done postoperatively at baseline, 2nd, 4th, 6th, and 8th weeks to assess volume and mineral density of newly formed bone (NFB) and beta-TCP. Results : Significant increase in NFB volume (NFBV) and mineral density (NFBMD) were observed from baseline to 8-weeks in all groups. Based on longitudinal in vivo micro-CT at 8-weeks, beta-TCP + PDGF group had significantly higher ( p  < 0.01) NFBV (38.98 ± 7.36 mm 3 ) and NFBMD (3.72 ± 0.32 g/mm 3 ) than the beta-TCP (NFBV-31.15 ± 6.68 mm 3 ; NFBMD-2.28 ± 0.86g/mm 3 ) and control (NFBV: 5.60 ± 1.06 mm 3 ; NFBMD: 0.27 ± 0.02 g/mm 3 ) groups. Significantly, higher reduction in beta-TCP volume (TCPV) and mineral density (TCPMD) were 1 observed in the beta-TCP + PDGF group when compared to the beta-TCP group. Conclusion : Addition of recombinant PDGF to beta-TCP enhanced bone regeneration within rat femoral CSSD and increased resorption rates of beta-TCP particles.

Background and objectives : Guided bone regeneration (GBR) is commonly used for osseous defect reconstruction. The objective of this study was to evaluate in real-time ( in-vivo ) the efficacy of equine bone graft for GBR in segmental critical-size defects (CSD) of the femur in a rat model. Materials and methods : Following ethical approval, 30 male Wistar-Albino rats (age 12-14 months/weight 450-500 grams) were included. Under general-anesthesia, a mid-diaphyseal segmental CSD (5 mm) was created in the femur and stabilized using titanium Miniplate(4 holes,1.0 mm thickness). Depending upon material used for GBR, animals were randomly divided into three groups(n = 10/per group). Negative control-Defect covered with resorbable collagen membrane(RCM); Positive control-Defect filled with autologous bone and covered by RCM; Equine bone-Defect filled with equine bone and covered by RCM. Real-time in-vivo Micro-CT was performed at baseline, 2, 4, 6 and 8 weeks to determine volume and mineral density of newly formed bone (NFB) and remaining bone graft particles (BGP). Results: In-vivo micro-CT revealed increase in volume and mineral density of NFB within defects from baseline to 8-weeks in all groups. At 8-weeks NFB-volume in the equine bone group(53.24 ± 13.83 mm 3 ; p < 0.01) was significantly higher than the negative control(5.6 ± 1.06 mm 3 ) and positive control(26.07 ± 5.44 mm 3 ) groups. Similarly, NFB-mineral density in the equine bone group(3.33 ± 0.48 g/mm 3 ; p < 0.01) was higher than the other (negative control-0.27 ± 0.02 g/mm 3 ; positive control-2.55 ± 0.6 g/mm 3 ). A gradual decrease in the BGP-volume and BGP-mineral density was observed. Conclusion : The use of equine bone for GBR in femoral segmental defects in rats, results in predictable new bone formation as early as 2-weeks after bone graft placement.

Background: Vertical bone augmentation (VBA) remains unpredictable and challenging for most clinicians. This study aims to compare hard tissue outcomes of VBA, with and without recombinant human bone morphogenetic protein (rhBMP)-2, under space-making titanium mesh in a canine model., Methods: Eleven male beagle dogs were used in the study. Experimental ridge defects were created to form atrophic ridges. VBA was performed via guided bone regeneration using titanium mesh and allografts. In experimental hemimandibles, rhBMP-2/absorbable collagen sponge was well mixed with allografts prior to procedures, whereas a control buffer was applied within controls. Dogs were euthanized after a 4-month healing period. Clinical and radiographic examinations were performed to assess ridge dimensional changes. In addition, specimens were used for microcomputed tomography (micro-CT) assessment and histologic analysis., Results: Membrane exposure was found on five of 11 (45.5%) rhBMP-2-treated sites, whereas it was found on nine of 11 (81.8%) non-rhBMP-2-treated sites. Within 4 months of healing, rhBMP-2-treated sites showed better radiographic bone density, greater defect fill, and significantly more bone gain in ridge height (P <0.05) than controls. Experimental hemimandibles exhibited lower rates of membrane exposure and a noteworthy, ectopic bone formation above the mesh in 72% of sites. Results from micro-CT also suggested a trend of less vertical bone gain and bone mineral density in controls (P >0.05). Under light microscope, predominant lamellar patterns were found in the specimen obtained from rhBMP-2 sites., Conclusion: With inherent limitations of the canine model and the concern of such a demanding surgical technique, current findings suggest that the presence of rhBMP-2 in a composite graft allows an increase of vertical gain, with formation of ectopic bone over the titanium mesh in comparison with non-rhBMP-2 sites.

We developed time trend model, determined treatment outcome and estimated annual human deaths among dog bite victims (DBVs) from 2010 to 2013 in Monrovia, Liberia. Data obtained from clinic records included victim's age, gender and site of bite marks, site name of residence of rabies-exposed patients, promptness of care sought, initial treatment and post-exposure-prophylaxis (PEP) compliance. We computed DBV time-trend plot, seasonal index and year 2014 case forecast. Associated annual human death (AHD) was estimated using a standardized decision tree model. Of the 775 DBVs enlisted, care seeking time was within 24h of injury in 328 (42.32%) DBVs. Victim's residential location, site of bite mark, and time dependent variables were significantly associated with treatment outcome (p< 0.05). The equation X^ t =28.278-0.365t models the trend of DBVs. The high (n=705, 90.97%) defaulted PEP and average 155 AHD from rabies implied urgent need for policy formulation on national programme for rabies prevention in Liberia., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Guided bone regeneration (GBR) procedures using graft materials have been used for reconstruction of osseous defects. The aim of the present in vivo micro-computed tomographic (µCT) and histologic study was to assess in real time the bone regeneration at GBR sites in standardized experimental calvarial defects (diameter 3.3 mm) using β-tricalcium phosphate (β-TCP) with and without collagen membrane (CM). A single full-thickness calvarial defect was created on the left parietal bone in young female Wistar albino rats (n = 30) weighing approximately 300 g and aged about 6 weeks. The animals were randomly divided into three groups for treatment, based on calvarial defect filling material: (1) control group (n = 10); (2) β-TCP + CM group (n = 10); (3) β-TCP group (n = 10). Real-time in vivo µCT analyses were performed immediately after surgery and at 2, 4, 6 and 10 weeks to determine the volume and mineral density of the newly formed bone (BVNFB, MDNFB) and remaining β-TCP particles (VRBP, MDRBP). The animals were killed at 10 weeks and calvarial specimens were evaluated histologically. In the control group, MDNFB increased significantly at 6 weeks (0.32 ± 0.002 g/mm(3), P < 0.01) compared to that at baseline. In β-TCP + CM group, BVNFB (1.10 ± 0.12 mm(3), P < 0.01) and MDNFB (0.13 ± 0.02 g/mm(3), P < 0.01) significantly increased at the 4th week than baseline. In the β-TCP group, BVNFB (1.13 ± 0.12 mm(3), P < 0.01) and MDNFB (0.14 ± 0.01 g/mm(3), P < 0.01) significantly increased at 6 weeks compared to that at baseline. Significant reduction in VRBP was neither seen in the β-TCP + CM group nor in the β-TCP group. While in the β-TCP + CM group MDRBP was reduced significantly at 6 weeks (0.44 ± 0.9 g/mm(3), P < 0.01) from baseline (0.98 ± 0.03 g/mm(3)), similar significant reduction in MDRBP from baseline (0.92 ± 0.07 g/mm(3)) was seen only at 10 weeks (0.45 ± 0.06 g/mm(3), P < 0.05) in the β-TCP group. Histologic findings at 10 weeks revealed greater amount of NFB with osteocytes in the matrix, in the β-TCP + CM group than in the β-TCP group. Biomechanical assessment of NFB for hardness (H) and elastic modulus (E) revealed significantly higher values for the β-TCP + CM group (H = 612.6 ± 4.28 Mpa; E = 13.57 ± 0.07 Gpa) when compared to those of the control (H = 192.1 ± 4.93 Mpa; E = 6.76 ± 0.04 Gpa) and the β-TCP groups (H = 241.9 ± 6.29 Mpa; E = 4.34 ± 0.06 Gpa). In conclusion, based on real-time assessment, NFB is formed in calvarial defects as early as 4 weeks following GBR with β-TCP + CM as compared to 6 weeks when β-TCP alone was used.

The aim of the present real time in vivo micro-computed tomography (µCT) and histologic experiment was to assess the efficacy of guided bone regeneration (GBR) around standardized calvarial critical size defects (CSD) using bone marrow-derived mesenchymal stem cells (BMSCs), and collagen membrane (CM) with and without tricalcium phosphate (TCP) graft material. In the calvaria of nine female Sprague-Dawley rats, full-thickness CSD (diameter 4.6 mm) were created under general anesthesia. Treatment-wise, rats were divided into three groups. In group 1, CSD was covered with a resorbable CM; in group 2, BMSCs were filled in CSD and covered with CM; and in group 3, TCP soaked in BMSCs was placed in CSD and covered with CM. All defects were closed using resorbable sutures. Bone volume and bone mineral density of newly formed bone (NFB) and remaining TCP particles and rate of new bone formation was determined at baseline, 2, 4, 6, and 10 weeks using in vivo µCT. At the 10th week, the rats were killed and calvarial segments were assessed histologically. The results showed that the hardness of NFB was similar to that of the native bone in groups 1 and 2 as compared to the NFB in group 3. Likewise, values for the modulus of elasticity were also significantly higher in group 3 compared to groups 1 and 2. This suggests that TCP when used in combination with BMSCs and without CM was unable to form bone of significant strength that could possibly provide mechanical "lock" between the natural bone and NFB. The use of BMSCs as adjuncts to conventional GBR initiated new bone formation as early as 2 weeks of treatment compared to when GBR is attempted without adjunct BMSC therapy.

In vivo microcomputed tomography (μCT) enables real-time assessment of bone regeneration. The aim of this μCT and histologic experiment was to assess guided bone regeneration (GBR) around standardized calvarial defects in rats using particulate graft material (Bio-Oss) with and without collagen membranes (CMs). Eighteen female Sprague-Dawley rats aged 6 weeks and weighing 300 g were used. With the rats under general anesthesia, calvaria were exposed and a full-thickness standardized defect was created on the parietal bone. For treatment, rats were randomly assigned to the following three groups: (1) CM group; (2) Bio-Oss group; and (3) Bio-Oss + CM group. Bone volume and bone mineral density (BMD) of newly formed bone (NFB) and remnant bone particles were measured at baseline and 2, 4, 6, and 10 weeks after the operations using real-time in vivo μCT. At 10 weeks, all animals were sacrificed and calvarial tissues were assessed histologically. In the CM group, a significant increase in mean ± standard deviation (SD) BMD of NFB was observed at 6 weeks (0.32 ± 0.02 g/mm(3)) (P < .01) compared with baseline. In the Bio-Oss group, mean ± SD volume (3.03 ± 0.14 mm(3)) (P < .05) and BMD (0.14 ± 0.01 g/mm(3)) of NFB significantly increased at 6 weeks compared with baseline (P < .01). In the Bio-Oss + CM group, mean ± SD volume (0.98 ± 0.19 mm(3)) and BMD (0.13 ± 0.01 g/mm(3)) of NFB significantly increased at 4 weeks compared with baseline (P < .01). In th Bio-Oss + CM group, mean ± SD volume (3.5 ± 0.7 mm(3)) and BMD (0.44 ± 0.03 g/mm(3)) of remnant bone particles were significantly reduced at 10 weeks compared with baseline values (5.8 ± 0.96 mm(3) and 1.3 ± 0.02 g/mm(3)) (P < .05). Although histologic analysis revealed NFB in all the study groups, the Bio-Oss + CM group exhibited the most. The results of this study revealed that, in real time, new bone formation starts as early as 4 weeks in standardized calvarial defects undergoing GBR with Bio-Oss + CM, compared with new bone formation at 6 weeks in defects undergoing GBR with Bio-Oss alone.

Guided bone regeneration (GBR) using a porcine-derived collagen matrix (Mucograft [MG], Geistlich) has not yet been reported. The aim of this histologic and biomechanical study was to compare the efficacy of MG versus resorbable collagen membranes (RCMs) in facilitating GBR around standardized rat calvarial defects. Forty female Wistar albino rats with a mean age and weight of 6 to 9 weeks and 250 to 300 g, respectively, were used. With the rats under general anesthesia, the skin over the calvaria was exposed using a full-thickness flap. A 4.6-mm-diameter standardized calvarial defect was created in the left parietal bone. For treatment, the rats were randomly divided into four groups (n = 10 per group): (1) MG group: the defect was covered with MG; (2) RCM group: the defect was covered with an RCM; (3) MG + bone group: the defect was filled with bone graft particles and covered by MG; and (4) RCM + bone group: the defect was filled with bone graft particles and covered by an RCM. Primary closure was achieved using interrupted resorbable sutures. The animals were sacrificed at 8 weeks after the surgical procedures. Qualitative histologic analysis and biomechanical assessment to identify hardness and elastic modulus of newly formed bone (NFB) were performed. Collected data were statistically analyzed using one-way analysis of variance. Histologic findings revealed NFB with fibrous connective tissue in all groups. The quantity of NFB was highest in the RCM + bone group. Statistically significant differences in the hardness (F = 567.69, dfN = 3, dfD = 36, P < .001) and elastic modulus (F = 294.19, dfN = 3, dfD = 36, P < .001) of NFB were found between the groups. Although the RCM + bone group had the highest mean ± standard deviation (SD) hardness of NFB (531.4 ± 24.9 MPa), the RCM group had the highest mean ± SD elastic modulus of NFB (18.63 ± 1.89 GPa). The present study demonstrated that RCMs are better than MG at enhancing new bone formation in standardized rat calvarial defects when used along with mineralized particulate graft material.

This study aimed to assess the efficacy of biphasic calcium phosphate (BCP) with adjunct recombinant human bone morphogenetic protein-2 (rhBMP-2), with and without collagen membrane (CM), in regeneration of standardized rat calvarial defects. Thirty female Wistar albino rats with a mean age of 12 weeks and mean weight of 300 g were used. The skin over the calvaria was exposed using a full-thickness flap. A standardized defect measuring 4.6 mm in diameter was created in the parietal bone. The defects were randomly divided into the following groups: (1) no treatment (control group); (2) BCP soaked in rhBMP-2 and then covered with a resorbable CM; and (3) BCP soaked in rhBMP-2. Following euthanasia, histologic, histomorphometric, and biomechanical assessments of the calvarial specimens were performed to assess bone regeneration. The results showed islands of newly formed bone (NFB) between the defect edges in the control group. NFB was observed bridging the defect edges and around the remnants of BCP in the rhBMP-2 + BCP + CM group and only around the BCP remnants in the rhBMP-2 + BCP group. Histomorphometric analysis revealed a significantly higher mean ± standard deviation (SD) percentage of NFB per defect in the rhBMP-2 + BCP + CM group (46.12 ± 2.56) compared with the control (11.79 ± 0.75) and rhBMP-2 + BCP (26.65 ± 1.48) groups. Although no differences were found in the hardness and elastic modulus (EM) of NFB between the rhBMP-2 + BCP + CM (hardness: 687.78 ± 4.74 MPa; EM: 27.71 ± 0.063 GPa) and the rhBMP-2 + BCP (hardness: 637.65 ± 6.32 MPa; EM: 21.49 ± 0.095 GPa) groups, the biomechanical parameters of NFB in the control group (hardness: 286.17 ± 9.49 MPa; EM: 12.62 ± 0.048 GPa) were significantly less. The experiment demonstrated the efficiency of rhBMP-2 + BCP in GBR, wherein the presence of CM leads to a greater percentage of new bone formation within standardized calvarial defects.

The aim of the present in vivo microcomputed tomographic (μCT), histologic, and biomechanical study was to assess the efficacy of bone marrow-derived mesenchymal stem cells (BMSCs) for promoting guided bone regeneration (GBR) in a standardized rat calvarial defect model. Forty female Wistar albino rats with a mean age of 7.5 months and mean weight of 275 g were used. Following calvarial exposure under general anesthesia, a full-thickness standardized calvarial defect (4.6 mm in diameter) was created. The study animals were randomly divided into four groups based on biomaterials used for GBR: (1) no treatment (negative control); (2) bone graft alone; (3) bone graft placed in the defect and covered with a collagen membrane (CM); and (4) bone graft soaked in BMSCs and covered with a CM. Bone volume and bone mineral density (BMD) of newly formed bone (NFB) and remnant bone particles were determined at baseline and at 2, 4, 6, 8, and 24 weeks postoperative using real time in vivo μCT. Histologic and biomechanical analyses of calvarial specimens were performed at 24 weeks, when the rats were euthanized. Statistically significant differences in volume and BMD of NFB were observed between and within the groups at different data collection periods. Significant increases in volume and BMD of NFB occurred as early as week 2 in all groups except the negative control. While the greatest volume of NFB was observed in the bone graft + BMSC + CM group, BMD of NFB was significantly higher in the bone graft + CM group. Statistically significant decreases in volume and BMD of remnant bone particles were also observed between the groups. Histologic analysis revealed NFB in all groups. The hardness and elastic modulus of NFB in the bone graft + BMSC + CM group were significantly higher than that in the other groups and also similar to adjacent natural bone. This study shows that using adjunct BMSCs with bone graft and CM for guided bone regeneration in standardized rat calvarial defects resulted in the highest quality and quantity of NFB.

The aim of this in vivo microcomputed tomographic (μCT) study was to compare the efficacy of Mucograft (MG) vs resorbable collagen membranes (RCMs) in facilitating guided bone regeneration (GBR) around standardized calvarial defects in rats. Forty female Wistar albino rats with a mean age and weight of 6 to 9 weeks and 250 to 300 g, respectively, were used. With the rats under general anesthesia, the skin over the calvaria was exposed using a full-thickness flap. A standardized calvarial defect with a 4.6-mm diameter was created in the left parietal bone. For treatment, the rats were randomly divided into four groups (n = 10 per group): (1) defects covered with MG (MG group); (2) defects covered with an RCM (RCM group); (3) defects filled with xenograft bone particles and covered by MG (MG + bone group); and (4) defects filled with xenograft bone particles and covered by an RCM (RCM + bone group). Primary closure was achieved using interrupted resorbable sutures. The animals underwent high-resolution, three-dimensional μCT scans at baseline and at 2, 4, 6, and 8 weeks after the surgical procedures. Data regarding volume and bone mineral density (BMD) of newly formed bone (NFB) and bone particles revealed an increase in the volume of NFB in all the groups from baseline to 8 weeks. The MG group had the lowest volume of NFB (mean ± standard deviation [SD], 1.32 ± 0.22 mm(3)). No significant differences in mean ± SD values for volume of NFB were observed between the RCM (3.50 ± 0.24 mm(3)) and MG + bone (3.87 ± 0.36 mm(3)) groups, but their values were significantly lower than that of the RCM + bone group (2.95 ± 0.15 mm(3), F = 131.91, dfN = 2, dfD = 27, P < .001). Significant differences in BMD of NFB between the groups (F = 332.46, dfN = 3, dfD = 36, P < .001) and during different data collection periods (F = 97.04, dfN = 3, dfD = 36, P < .01) were observed, with the RCM group having the highest mean ± SD BMD of NFB (0.42 ± 0.05 g/mm(3)). Significant differences in the bone particle volume between the RCM + bone and MG + bone groups (F = 91.04, dfN = 1, dfD = 18, P < .05) and at different data collection periods (F = 314.12, P < .01) were observed, with the RCM + bone group displaying greater reduction in both volume (36.8%) and BMD (19.7%) of bone particles. The present in vivo μCT study demonstrated that RCM is better than MG in enhancing new bone formation in rat calvarial standardized defects when used in combination with mineralized particulate graft material.

The aim of this in vivo microcomputed tomographic (μCT) experiment was to assess in real time the efficacy of a combination of recombinant human bone morphogenetic protein-2 (rhBMP-2) and biphasic calcium phosphate (BCP), with and without resorbable collagen membrane (CM), in regeneration of standardized calvarial defects (SCDs) in rats. A total of 30 female Wistar albino rats (n = 10/group) with a mean age and weight of 7.5 months and 275 g, respectively, were used. With the rats under general anesthesia, the calvaria were exposed using full-thickness periosteal flaps and unilateral SCDs of 4.6 mm diameter were created on the left parietal bone. Defects were left untreated (control group) or randomly filled with either BCP soaked in rhBMP-2 and then covered with CM (BMP + BCP + CM group) or BCP soaked in rhBMP-2 alone (BMP + BCP group). In vivo μCT scans were done at baseline and 2, 4, 6, and 8 weeks. Newly formed bone (NFB) and remaining BCP particles were assessed for their volumes (NFBV, BCPV, respectively) and mineral densities (NFBMD, BCPMD, respectively). In vivo μCT results showed scanty amounts of new bone at the peripheries of the defect in the control group. In the other two groups, near complete defect closure was evident at 8 weeks. The mean NFBV after 8 weeks was 4.63 ± 0.96 mm(3), 11.82 ± 1.17 mm(3), and 13.85 ± 1.89 mm(3) for the control, BMP + BCP + CM, and BMP + BCP groups, respectively. After 8 weeks, the mean NFBMD was 0.38 ± 0.03 g/mm(3), 0.24 ± 0.07 g/mm(3), and 0.35 ± 0.03 g/mm(3) for the control, BMP + BCP + CM, and BMP + BCP groups, respectively. After 8 weeks, the mean BCPV and BCPMD values for the BMP + BCP + CM and BMP + BCP groups were 2.73 ± 0.65 mm(3), 0.33 ± 0.08 g/mm(3), 2.49 ± 0.71 mm(3), and 0.28 ± 0.03 g/mm(3), respectively. The present real-time in vivo μCT experiment demonstrated that BMP + BCP, either with or without CM, was effective in promoting bone regeneration within rat SCDs and enabled new bone formation starting as early as 2 weeks.

The aim of the present in vivo microcomputed tomography (μCT) and histologic experiment was to assess the efficacy of guided bone regeneration (GBR) around standardized calvarial defects using recombinant human platelet-derived growth factor (rhPDGF) with and without resorbable collagen membrane (RCM). A total of 50 female Wistar albino rats with a mean age of 7.5 months and mean weight of 275 g were used. The calvarium was exposed following midsagittal scalp incision and flap reflection. A full-thickness standardized calvarial defect (4.6 mm diameter) was created. Study animals were randomly divided into five groups based on biomaterials used for GBR within the defect: (1) no treatment (negative control), (2) bone graft alone (BG), (3) bone graft covered by RCM (BG + RCM), (4) bone graft soaked in rhPDGF (BG + rhPDGF), and (5) bone graft soaked in rhPDGF and covered with RCM (BG + rhPDGF + RCM). In vivo μCT for determination of newly formed bone volume (NFBV) and mineral density (NFBMD) and remnant bone particles volume (RBPV) and mineral density (RBPMD) was done at baseline and at 2, 4, 6, and 8 weeks postoperatively. Eight weeks following surgery, the animals were sacrificed and harvested calvarial specimens were subjected to histologic and biomechanical analysis. There was an increase in NFBV and NFBMD associated with a corresponding decrease in RBPV and RBPMD in all the study groups. Two-way analysis of variance revealed significant differences in the measured values within and between the groups across the timelines examined during the study period (P < .05). While the NFBV was significantly higher in the bone graft, BG + RCM, and BG + rhPDGF + RCM groups, the NFBMD was similar in all the groups except negative control. The greatest decreases in RBPV and RBPMD were observed in the BG + rhPDGF + RCM group in comparison to the other groups. Similarly, BG + rhPDGF + RCM groups had hardness and elastic modulus similar to that of natural bone. The in vivo μCT results were validated by the qualitative histologic findings. In real time, new bone formation starts as early as 2 weeks in rat calvarial defects treated with bone graft and rhPDGF, irrespective of the presence or absence of RCM.

The objective of the present real-time in vivo experiment was to assess guided bone regeneration (GBR) in standardized calvarial defects using particulate graft material (Bio-Oss) and β-tricalcium phosphate (β-TCP) with adjunct recombinant human platelet-derived growth factor (rhPDGF) therapy. Eighteen female Sprague-Dawley rats with a mean age and weight of 8 ± 0.53 weeks and 250 ± 0.49 g, respectively, were used. Following surgical exposure, a full-thickness standardized calvarial defect was created on the parietal bone using a trephine drill with an outer diameter of 4.6 mm. For treatment, rats were randomly divided into three groups (six rats per group): (1) control; (2) rhPDGF + Bio-Oss, and (3) rhPDGF + β-TCP. Volume of newly formed bone (NFB), bone mineral density (BMD) of NFB, volume of remnant bone particles, and BMD of remnant bone particles were assessed using in vivo microcomputed tomography. Measurements were made at baseline and at 2, 4, 6, and 10 weeks after the surgical procedures. At 10 weeks, all animals were sacrificed and calvarial tissues were assessed histologically. In the control group, a significant increase in BMD of NFB was observed at 6 weeks (mean ± standard deviation [SD], 0.32 ± 0.002 g/mm(3)) (P < .01) from baseline, and the defect did not regenerate completely. In the rhPDGF + Bio-Oss group, mean ± SD volume (2.40 ± 0.25 mm(3)) (P < .01) and BMD (0.13 ± 0.01 g/mm(3)) of NFB significantly increased at 4 weeks and 6 weeks, respectively, from baseline (P < .001). In the rhPDGF + β-TCP group, mean ± SD volume (2.01 ± 0.7 mm(3)) and BMD (0.12 ± 0.02 g/mm(3)) of NFB significantly increased at 4 weeks from baseline (P < .01). In the rhPDGF + Bio-Oss and rhPDGF + β-TCP groups, mean ± SD BMD of remnant bone particles (0.31 ± 0.11 g/mm(3) and 0.23 ± 0.01 g/mm(3)) showed significant reduction at 6 and 10 weeks, respectively, compared with baseline values (1.12 ± 0.06 g/mm(3) and 0.92 ± 0.01 g/mm(3), respectively) (P < .001). Histologic results at 10 weeks showed NBF in the rhPDGF + Bio-Oss and rhPDGF + β-TCP groups. In real time assessment, when rhPDGF was added to β-TCP, BMD and bone hardness significantly increased compared with the other two groups.

Objectives: The aim of the present study was to assess and compare the shear bond strength (SBS) of metal pre-coated orthodontic brackets bonded to fluorotic and non-fluorotic teeth treated with three different etching techniques. A second aim was to determine the volume of adhesive remaining on the tooth at debond using micro-computed tomography (μCT)., Methods: Ninety extracted premolars were selected to include 45 fluorotic (test group) and 45 non-fluorotic (control group) teeth. Each group was divided into three subgroups of 15 each, which were treated as follows: 1) micro-etched; 2) acid-etched; and 3) both micro-etched and acid-etched. A bonding agent was applied to the prepared surfaces; pre-coated and light-cured brackets were attached to all teeth. An Instron universal testing machine was used to record the debonding force. Specimens were then scanned using a microCT to evaluate the amount of adhesive remaining on the teeth. The significance of the statistical tests was pre-determined at p < 0.05., Results: Two-way ANOVA showed that fluorosis of teeth had no influence on the SBS (p = 0.165) whereas the volume of adhesive remnants was significantly higher in the control group compared with the test group (p < 0.001)., Conclusions: Fluorosis had no influence on the SBS of brackets, whereas it had a negative influence on retaining adhesives onto the tooth surfaces.

Objectives: This study aimed to evaluate the biologic and structural phenotypes of the bone regenerated via the sandwich bone augmentation (SBA) technique, on buccal implant dehiscence defects., Material and Methods: Twenty-six patients with one buccal implant dehiscence defect each were randomly assigned to two groups. Both groups received a standardized amount of mineralized cancellous and cortical allogenic bone graft. In the test group, a bovine pericardium membrane was placed over the graft, while no membrane was placed in the control group. After 6 months of healing, a bone core biopsy of the regenerated bone was harvested and processed for histologic, immunohistochemical, mRNA, and micro-computed tomography (μCT) analyses. Of the 26 bone core biopsies, only six cores from the test group and six cores from the control group were suitable for the analysis., Results: Bone volume (BV) in the test group was maintained, but tissue maturation appeared to be delayed. In contrast, tissue maturation appeared to be completed in the control group, but BV was compromised. Micro-CT analysis showed that specimens from the control group were more structured and mineralized compared with those from the test group. Histologic analysis showed more residual graft particles scattered in a loose fibrous connective tissue matrix with sparse bone formation in the test group, while the control group showed obvious vital bone formation surrounding the residual graft particles. Positive periostin (POSTN), sclerostin, and runt-related transcription factor-2 (RUNX2) immunoreactivities were detected in both the control and test groups. However, tartrate-resistant acid phosphatase (TRAP) positive was mostly noted in the control group. There were significant differences in POSTN, RUNX2 and VEGF expressions between the test and control groups., Conclusion: These findings indicated that the SBA technique was an effective method in preserving adequate structural volume while promoting new vital bone formation. Use of the collagen barrier membrane has successfully maintained the volumetric dimensions of the ridge but might have slowed down the complete maturation of the outermost layer of the grafted site., (© 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

In untreated extraction sockets, buccal bone remodeling compromises the alveolar ridge width. The aim of this study was to histologically assess the efficacy of using a dual layer of membranes (high-density polytetrafluoroethylene [dPTFE] placed over collagen) for ridge preservation in fresh extraction sites. Eight beagle dogs were used. After endodontic treatment of mandibular bilateral second (P2), third (P3), and fourth (P4) premolars, mandibular bilateral first premolars and distal roots of P2, P3, and P4 were extracted atraumatically. Animals were randomly divided into 4 treatment groups. group 1, the control group, received no treatment; in group 2, allograft was placed in the alveolum and the socket covered with dPTFE membrane; in group 3, allograft was placed in the alveolum, the buccal plate was overbuilt with allograft, and the socket was covered with dPTFE membrane; in group 4, allograft was placed in the alveolum and covered with dual layer of membranes (dPTFE placed over collagen). No intent of primary closure was performed for all groups. After 16 weeks, the animals were sacrificed and mandibular blocks were assessed histologically for buccolingual width of alveolar ridge, percentage of bone formation and bone marrow spaces, and the remaining bone particles. The buccolingual width of the alveolar ridge was significantly higher among sockets in group 4 than in group 1 (P < .05). the amount of newly formed bone in each socket was higher in extraction sockets in group 4 than in groups 1, 2, and 3 (P < .001). A significant difference was found in the percentage of bone marrow spaces among all groups (P < .001). No significant difference was found in the number of nonresorbed bone particles among the groups. Using a dual layer of membrane was more effective in ridge preservation than conventional socket augmentation protocols.

Background: Achieving a good apical seal for root canals is known to be associated with good mineral trioxide aggregate (MTA) adaptation to dentin., Aims: This study aims to compare the marginal adaptation of MTA with root dentin between orthograde and retrograde application techniques using microcomputed tomography (micro-CT) analysis., Settings and Design: Fifty-two single-rooted human teeth were divided into four equal groups: (Group 1) Retrograde MTA (RMTA), (Group 2) Orthograde MTA (OMTA), (Group 3) Etched RMTA (ERMTA), and (Group 4) Etched OMTA (EOMTA)., Materials and Methods: For Group 1, 3-mm retrograde cavities were prepared and filled with MTA. For Group 2, the apical 6 mm of the canals were filled with MTA and sealed with sealer cement and warm gutta-percha. In Groups 3 and 4, canals were treated the same as Groups 1 and 2, respectively, except that before placing the MTA, canals were irrigated with 17% ethylenediaminetetraacetic acid (EDTA). After 48 hours, all the teeth were analyzed using a micro-CT scanner., Statistical Analysis: Mean dentin-MTA contact and the mean length and width of each gap was analysed using one-way analysis of variance (ANOVA). Statistical significance was set at an α level of 5%., Results: No significant difference in gap volumes was observed in the dentin-MTA adaptation in both orthograde and retrograde application techniques. However, significant difference in the gap volumes was observed between RMTA and ERMTA (P = 0.045). Etching significantly improved the MTA-Dentin adaptation (P < 0.05). The type of application technique did not significantly improve the dentin-MTA adaptation, instead with the use of 17% EDTA, a significant improvement could be achieved., Conclusion: Within the limitations of the present study, it concludes that MTA adaptation to dentin tooth structure is not significantly different between an orthograde and retrograde approach. However, the use of EDTA significantly improved the MTA-Dentin adaptation.

Introduction: The purpose of this randomized controlled clinical trial was to evaluate 2 different techniques for vertical ridge augmentation (VRA) of the posterior mandible., Materials and Methods: Sixteen subjects with 19 posterior mandibular edentulous sites requiring VRA were recruited for the study. Sites were randomly treated with either block allograft (BA; N = 9) or sandwich bone augmentation (SBA; N = 10). Clinical measurements were recorded at the time of surgery (baseline) and 6-month reentry with a custom-made acrylic surgical template., Results: The mean vertical bone gain (VBG) after mean 6.8 months was 44.5% (mean = 1.78 mm [0-5 mm]) in the BA group and 33.3% (mean = 1.0 mm [-1 to 3 mm]) in the SBA group. Significantly higher rates of incision line openings and wound dehiscences were found in the BA group (n = 7/9, 77.8%) as compared with the SBA group (n = 3/10, 30%) (P = 0.037). After adjusting for graft exposure, BA group demonstrated significantly higher VBG than SBA (difference = 2.26 mm, P < 0.001). In addition, graft exposure resulted in significantly less VBG in both groups (P < 0.001)., Conclusions: A higher tendency of wound exposure during VRA was demonstrated when a BA was used compared with the SBA technique. However, if wound exposure could be prevented, higher vertical ridge gain could be achieved with a BA., Summary: The use of a BA in VRA resulted in a maximum of 2 mm more bone height gain compared with the SBA technique if the primary coverage can be achieved during the healing.

Various designs of dental implants representing different geometries and surface technologies are commercially available for patient treatment. However, data with regard to the biologic events that occur immediately after implant placement, regardless of the surface characteristic, are scarce. It has become a common procedure to perform immediate/early prosthetic loading rather than delayed loading. The goal of this study was to observe the early biologic events of peri-implant healing to understand the role of surface modifications in relation to the early phases of bone integration. The secondary goal was to observe the possible differences in the healing pattern at two oral implant surfaces differing in morphology and roughness (Ra, with Ra values ranging from 0.5 μm (machined surface; MS) to 1.5 μm (oxidized surface; OS). A total of 36 implants were placed in six foxhound dogs, equally divided between machined and oxidized surfaces. Three implants were positioned per hemimandible following a randomization scheme. Each animal was euthanized at a specific time point for histologic observation and histomorphometry: immediately after implant insertion and after 24 hours, 7 days, 15 days, 30 days, and 90 days. The study demonstrated an extremely low bone-implant contact (BIC) for both OS and MS implant surfaces during the first 15 days after implant placement (ranging from 12.9% to 26.9% independent of the implant surface). Increased BIC values were observed only in the 30- and 90-day specimens. The presence and the degradation of residual bone particles acted as centers for new bone formation, with osteoblasts lining osteoid tissue and subsequently woven bone independent of the implant surface characteristics. The bone-forming activity appeared strongly reduced after 30 days of healing and seemed to be complete only in the 90-day specimens, where abundant lamellar bone was evident. There is a continuing effort to develop improved titanium surfaces to achieve more rapid osseointegration and improve BIC, with the ultimate goal of applying occlusal load as early as possible. Since immediate or early implant loading is applied during and not after the first 15 days, the findings in the present study of an extremely low BIC and limited mineralized bone formation for both implant surfaces during the first 15 days after implant placement suggest that the surface roughness may not be a key factor for successful osseointegration of immediately or early loaded implants. Within the limits of this study, it can be stated that osseointegration follows a similar healing pattern with machined and oxidized implant surfaces.

Background: The aim of this study is to assess the short-term effects of non-surgical periodontal therapy (NSPT) on the gingival crevicular fluid (GCF) cytokine profile in sites with standardized periodontal bony defects in beagle dogs with and without diabetes., Methods: Four beagle dogs with streptozotocin (STZ)-induced diabetes and four healthy dogs were included. Fasting blood glucose levels were measured using a glucometer. In all animals, a 3-walled bony defect was created on the mesial surface of the second premolar and first molar in all quadrants. After 12 weeks, all animals underwent weekly NSPT for 3 weeks. Baseline and post-NSPT GCF samples were collected, and levels of interleukin (IL)-1, IL-1β, IL-6, IL-8, and tumor necrosis factor (TNF)-α were measured using enzyme-linked immunosorbent assay. Statistical analyses were performed using a software program, and P values <0.05 were considered statistically significant., Results: Mean fasting blood glucose levels were significantly higher in dogs with induced diabetes than those without diabetes (P <0.01). At baseline, mean IL-6 (P <0.01) and IL-8 (P <0.05) levels were higher in dogs with diabetes than those without diabetes. A significant reduction in levels of IL-1, IL-1β, IL-6, IL-8, and TNF-α was noted in dogs without diabetes 1 week after NSPT. However, this significant reduction (P <0.05) only appeared 2 weeks after NSPT in dogs with diabetes., Conclusions: NSPT reduces GCF levels of proinflammatory cytokines in dogs with and without STZ-induced diabetes; however, chronic hyperglycemia seems to retard the effect of NSPT on GCF cytokine concentration.

A preclinical study was conducted to evaluate the feasibility of 2 different topical formulations of recombinant human platelet-derived growth factor-BB (rhPDGF-BB) to promote early osseointegration and enhanced bone-to-implant contact (BIC) for dental implants placed in an edentulous ridge. Six female beagle dogs were divided into 3 groups. The control group included 4 implants with no coating; test group A included 10 implants with commercially available rhPDGF-BB formulation coating; and second test group B included 10 implants with prototype viscous rhPDGF-BB coating. Three dogs were sacrificed at 3 weeks (12 implants) and the remaining 3 dogs at 6 weeks after implant placement (12 implants). The specimens were retrieved for histological evaluation, and revealed an uneventful healing of all implants without any sign of an inflammatory response at the different time intervals. Furthermore, the bone was in very close contact with the implants' surfaces with no evidence of intervening fibrous tissue layers. At 3 weeks, new bone formation between most implant threads on rhPDGF-BB coated implants was evident, whereas in the control group only a thin and sparse amount of new bone was noted. At 6 weeks, the commercially available rhPDGF-BB formulation coated implant group (Group A) showed more trabecular bone and higher BIC compared to the other 2 groups. Histologically, the results in this study showed that use of conventionally available rhPDGF-BB formulation as the implant surface treatment may accelerate the process of osseointegration and enhance BIC.

Aging-related bone loss and osteoporosis affect millions of people worldwide. Chronic inflammation associated with aging promotes bone resorption and impairs bone formation. Here we show that Wnt4 attenuates bone loss in osteoporosis and skeletal aging mouse models by inhibiting nuclear factor-κB (NF-κB) via noncanonical Wnt signaling. Transgenic mice expressing Wnt4 from osteoblasts were significantly protected from bone loss and chronic inflammation induced by ovariectomy, tumor necrosis factor or natural aging. In addition to promoting bone formation, Wnt4 inhibited osteoclast formation and bone resorption. Mechanistically, Wnt4 inhibited NF-κB activation mediated by transforming growth factor-β-activated kinase-1 (Tak1) in macrophages and osteoclast precursors independently of β-catenin. Moreover, recombinant Wnt4 alleviated bone loss and inflammation by inhibiting NF-κB in vivo in mouse models of bone disease. Given its dual role in promoting bone formation and inhibiting bone resorption, our results suggest that Wnt4 signaling could be an attractive therapeutic target for treating osteoporosis and preventing skeletal aging.

Unlabelled: Oral health status is jeopardized in patients with neurofibromatosis (NF) type-1 (NF-1). The aim of the present study was to comprehensively review the oral manifestations in NF-1 patients. PubMed/Medline and Google-Scholar databases were explored using different keywords. Reviews, commentaries, letters to Editor and articles published in languages other than English were excluded., Results: Neurofibromas of oral and perioral soft tissues with subsequent periodontitis, impacted and supernumerary teeth, enlarged alveolar process with dental spacing, morphological changes in teeth and class III molar relationship have been reported in NF-1 patients. Plexiform neurofibromas were reported both in oral soft tissue, maxilla and mandible with evidence of malignant transformation in some cases. Facial skeletal abnormalities, including enlargement of mandibular foramen, increased dimensions of the coronoid and sigmoid notches and notching of the posterior border of the mandible have also been reported. Association between dental caries and NF-1 remains unclear., (Crown Copyright © 2014. Published by Elsevier Ireland Ltd. All rights reserved.)

The aim of this study was to histologically assess alveolar bone remodeling around immediate implants placed in single and multiple contiguous extraction sites. Ten dogs were divided into three groups (with six sites per group) on the basis of premolar teeth extraction: group 1 = one tooth extracted, group 2 = two contiguous teeth extracted, and group 3 = more than two contiguous teeth extracted. Immediate implants were placed in each group. Histologic assessment of arches showed no evidence of vertical bone loss (VBL) around implants in group 1 compared with groups 2 (P < .001) and 3 (P < .001). Buccal and lingual bone thicknesses and bone-to-implant contact (BIC) were higher around implants in group 1 compared with groups 2 (P < .001) and 3 (P < .05). Buccal and lingual bone thicknesses, BIC, and VBL are compromised around implants in multiple contiguous extraction sites compared with those in a single extraction site.