Effect of Recombinant Human Platelet-Derived Growth Factor on Healing of Chronic Periapical Tissue Pathosis Following Apical Surgery in a Canine Model: A Histomorphometric and Microcomputed Tomography Analysis.

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.

Effect of Selective Serotonin Reuptake Inhibitor (Paroxetine) on Newly Formed Bone Volume: Real-Time In Vivo Micro-computed Tomographic Analysis.

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 mm3 and 12.52 ± 4.78 mm3 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.

The Efficacy of Recombinant Platelet-Derived Growth Factor on Beta-Tricalcium Phosphate to Regenerate Femoral Critical Sized Segmental Defects: Longitudinal In Vivo Micro-CT Study in a Rat Model.

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 mm3) and NFBMD (3.72 ± 0.32 g/mm3) than the beta-TCP (NFBV-31.15 ± 6.68 mm3; NFBMD-2.28 ± 0.86g/mm3) and control (NFBV: 5.60 ± 1.06 mm3; NFBMD: 0.27 ± 0.02 g/mm3) 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.

Guided Bone Regeneration of Femoral Segmental Defects using Equine Bone Graft: An In-Vivo Micro-Computed Tomographic Study in Rats.

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 mm3; p < 0.01) was significantly higher than the negative control(5.6 ± 1.06 mm3) and positive control(26.07 ± 5.44 mm3) groups. Similarly, NFB-mineral density in the equine bone group(3.33 ± 0.48 g/mm3; p < 0.01) was higher than the other (negative control-0.27 ± 0.02 g/mm3; positive control-2.55 ± 0.6 g/mm3). 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.

Real-Time Assessment of Guided Bone Regeneration in Standardized Calvarial Defects Using a Combination of Bone Graft and Platelet-Derived Growth Factor With and Without Collagen Membrane: An In Vivo Microcomputed Tomographic and Histologic Experiment in Rats.

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.

Efficacy of Mesenchymal Stem Cells as Adjunct to Guided Bone Regeneration in Standardized Calvarial Defects in Rats: An In Vivo Microcomputed Tomographic and Histologic Analysis.

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.

Real-time-guided bone regeneration around standardized critical size calvarial defects using bone marrow-derived mesenchymal stem cells and collagen membrane with and without using tricalcium phosphate: an in vivo micro-computed tomographic and histologic experiment in rats.

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.

Guided bone regeneration in standardized calvarial defects using beta-tricalcium phosphate and collagen membrane: a real-time in vivo micro-computed tomographic experiment in rats.

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 ß-tricalcium phosphate (ß-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) ß-TCP + CM group (n = 10); (3) ß-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 ß-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 ß-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 ß-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 ß-TCP + CM group nor in the ß-TCP group. While in the ß-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 ß-TCP group. Histologic findings at 10 weeks revealed greater amount of NFB with osteocytes in the matrix, in the ß-TCP + CM group than in the ß-TCP group. Biomechanical assessment of NFB for hardness (H) and elastic modulus (E) revealed significantly higher values for the ß-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 ß-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 ß-TCP + CM as compared to 6 weeks when ß-TCP alone was used.

Ridge preservation surgery after single and multiple adjacent tooth extractions: a microcomputed tomography study in dogs.

PURPOSE: The aim of this study was to determine, before implant placement, the outcome of ridge preservation surgery after extractions of one or more adjacent teeth on the dimensions of the edentulous ridge. MATERIALS AND METHODS: Nineteen extraction sites in four dogs were randomly divided into three groups: group 1 = single premolars (n = 7 sites); group 2 = two adjacent premolars (n = 6 sites); group 3 = three adjacent premolars (n = 6 sites). Extraction was followed by ridge preservation surgery using a combination of xenograft and collagen membrane after full-thickness flap reflection. All animals were sacrificed 4 months later, and each extraction site was sectioned in the sagittal plane so that alveolar bone measurements could be made in both the buccolingual and apicocoronal directions using microcomputed tomography. RESULTS: Mean buccolingual width of the ridges postsurgery was 4.80 ± 2.78 mm, 4.98 ± 2.65 mm, and 4.79 ± 2.79 mm in groups 1, 2, and 3, respectively. The mean vertical distance from the cementoenamel junction to the crest of the ridge was 1.94 ± 0.42 mm, 2.05 ± 0.48 mm, and 2.60 ± 0.67 mm in groups 1, 2, and 3, respectively. No statistically significant difference was seen between single and multiple extraction sites. CONCLUSION: Ridge preservation surgery results in a similar pattern of bone remodeling in the horizontal and vertical dimensions of the edentulous ridge after single and multiple adjacent tooth extractions.

A randomized clinical trial evaluating the efficacy of the sandwich bone augmentation technique in increasing buccal bone thickness during implant placement. II. Tomographic, histologic, immunohistochemical, and RNA analyses.

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.

Comparison between sandwich bone augmentation and allogenic block graft for vertical ridge augmentation in the posterior mandible.

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.

Wnt4 signaling prevents skeletal aging and inflammation by inhibiting nuclear factor-κB.

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-ß-activated kinase-1 (Tak1) in macrophages and osteoclast precursors independently of ß-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.

Efficacy of growth factor in promoting early osseointegration.

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.

Short-term effects of non-surgical periodontal treatment on the gingival crevicular fluid cytokine profiles in sites with induced periodontal defects: a study on dogs with and without streptozotocin-induced diabetes.

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-1ß, 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-1ß, 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.

Oral manifestations in patients with neurofibromatosis type-1: a comprehensive literature review.

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.

Evaluation of mandibular lingual foramina related to dental implant treatment with computerized tomography: a multicenter clinical study.

BACKGROUND: Bleeding can be one of the severe complications during implant placement or other surgeries. Presurgical assessment of the area should be performed precisely. Thus, we examined lingual vascular canals of the mandible using dental computerized tomography (CT); define the anatomical characteristics of canals and the relationship with mandibular bone. METHODS: One thousand sixty-one foramina in 639 patients, in 5 dental clinics, were included in this multicenter study. Distance between crest and lingual foramen, tooth apex and lingual foramen, distance from mandibular border, diameter of lingual foramen, canal type, anastomosis, and location of foramen were examined. RESULTS: Foramen was 18.33 ± 5.45 mm below the bony crest and 17.40 ± 7.52 mm from the mandibular border, with men showing larger measurements. The mean diameter of lingual foramina was 0.89 ± 0.40 mm; 76.8% canal type was mono; 51.8% patients presented with median lingual canal-foramen (MLC) and 21.1% with lateral lingual foramen. Diameter of MLC was statistically larger. CONCLUSIONS: With a large sample group, results represented that lingual foramina could be visualized with dental CT, providing useful data for mandibular implant surgeries. Findings suggest that vascular canals and several anastomoses exist in the anterior mandible extending through premolar and molar regions as well. It is imperative to consider these vessels with the dental CT before and during the mandibular surgery to prevent threatening hemorrhage.

Association between glycemic status and oral Candida carriage in patients with prediabetes.

OBJECTIVE: This study assessed the association between glycemic status and oral Candida carriage among patients with prediabetes. STUDY DESIGN: This was a comparative study of oral Candida carriage among individuals with prediabetes. Oral yeast samples were collected from 150 individuals: group A was 43 patients with prediabetes (fasting blood glucose levels and hemoglobin A1c, 100 to 125 mg/dL and ≥5%, respectively); group B was 37 individuals previously considered prediabetic but having fasting blood glucose levels <100 mg/dL and hemoglobin A1c <5%; and group C was 70 medically healthy individuals. Oral yeasts were identified using standard techniques. Unstimulated whole salivary flow rate and number of missing teeth were recorded. RESULTS: Oral Candida was isolated from 100% of patients with prediabetes and from 65.7% of control participants. Candida albicans carriage was higher among patients with prediabetes (48.7%) (P < .01) and patients in group A (51.2%) (P < .01) than among controls (25.7%). Candida carriage, unstimulated whole salivary flow rate, and number of missing teeth were similar in groups A and B. CONCLUSIONS: Oral Candida carriage was higher in patients with prediabetes than in controls and was independent of glycemic status in patients with prediabetes.

Evaluation of bone regenerative capacity following distraction osteogenesis of goat mandibles using two different bone cutting techniques.

PURPOSE: To compare the regenerative capacity of goat mandibles following sagittal split osteotomy and distraction osteogenesis with a vertical body osteotomy. ANIMALS AND METHODS: Bilateral vertical and sagittal body osteotomy was performed on the left and right sides of the mandibles in 18 goats. The distraction period lasted for 10 days at 1 mm/day. Animals were sacrificed at 0, 10, and 35 days post-distraction. Bone mineral density (BMD) and bone volume (BV) were analysed by microcomputed tomography (MCT). Types of bone and cells present in the regenerated defect sites were analysed histologically. RESULTS: At 0, 10, and 35 days, BMD was 0.358 ± 0.012, 0.410 ± 0.012, and 1.070 ± 0.019, respectively, for vertical osteotomy and 0.420 ± 0.013, 0.421 ± 0.009 and 1.182 ± 0.030, respectively, for sagittal osteotomy. BV was 973.310 ± 5.048, 1234.589 ± 4.159, and 2121.867 ± 6.519, respectively, for vertical osteotomy and 995.967 ± 2.781, 1755.938 ± 4.379, and 2618.441 ± 21.429, respectively, for sagittal osteotomy at these three time points. BMD and BV differed significantly at all three times. Histological analysis shows that sagittal splitting was characterized by more robust lamellar bone formation bridging the distraction gap than vertical body osteotomy. CONCLUSION: Both MCT and histological analyses showed that distraction using the sagittal osteotomy technique resulted in significantly higher BV and BMD than using vertical body osteotomy.

Oral Candida carriage and species prevalence amongst habitual gutka-chewers and non-chewers.

Oral Candida colonisation is higher in tobacco smokers as compared to non-smokers; however, it remains unknown whether smokeless tobacco chewers are susceptible to increased oral Candida colonisation. The aim was to determine the oral Candida carriage and species prevalence amongst habitual gutka-chewers and non-chewers in a cohort from Karachi, Pakistan. Forty-five gutka-chewers and 45 non-chewers were included. Information regarding age, sex, duration of gutka-chewing habit, daily frequency of gutka consumption, duration of holding gutka in the mouth, daily frequency of tooth-brushing and tongue brushing was collected using a questionnaire. Oral yeast samples were collected by scraping the dorsum of the tongue and bilateral buccal mucosa with a sterile cotton swab. Identification of yeast species was performed using standard techniques. Tongue lesions were identified and recorded. Unstimulated whole salivary flow rate (UWSFR) was also measured. There was no significant difference in the mean age, UWSFR and oral Candida carriage among gutka-chewers and non-chewers. Individuals were chewing gutka since 4·4 years and were consuming five gutka sachets daily. Candida albicans (C. albicans) was the most common yeast species isolated from 57·8% gutka-chewers and 64.4% non-chewers. In 24.4% gutka-chewers and 22·2% non-chewers, two candidal strains (C. albicans and Candida tropicalis) were isolated. In conclusion, the present results indicated no significant difference in oral Candida carriage in habitual gutka-chewers and non-chewers.