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Purpose@#The aim of this study was to investigate the association between the changes in masticatory function and cognitive impairment by analyzing longitudinal data of older Korean patients. @*Materials and Methods@#Patients aged over 60 years with dental records between 2005 to 2010 (baseline; T1) and 2014 to 2020 (follow-up; T2) were selected in a single medical center. Based on the dementia diagnosis after T2, the cohort was classified into two groups, the dementia group (n=122) and the control group (n=366). Changes in masticatory function were calculated using the total functional tooth unit (T-FTU) in both groups. The incidence of tooth extraction (%) and the subsequent rehabilitation during the observation period were also evaluated. @*Results@#In the dementia group, T-FTU significantly decreased from T1 to T2 (9.81±2.78 to 9.11±3.16, respectively, p=0.008), while no significant change was observed in the control group. During the mean observation period of 9 years, significantly more teeth were extracted and neglected to be prosthetically restored in the dementia group than in the control group. Regression analysis revealed that the number of missing teeth neglected [odds ratio (OR)=1.195, 95% confidence interval (CI)=1.025–1.393, p=0.023] and previous alcohol consumption (OR=4.445, 95% CI=1.831–1.795, p=0.001) were the most significant risk factors of dementia. @*Conclusion@#There might be a causative relationship between the neglected missing dentition and the onset of dementia.
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Purpose@#The aim of this study was to evaluate the bio-durability and bone regeneration capacity of the non-crosslinked collagen membrane in rabbit calvarial defect models. @*Materials and Methods@#Four circular defects with 8 mm diameter were made in each of calvarium of 10 male rabbits. The following groups was randomly assigned to each defect - 1) Control, 2) membrane group containing noncross-linked collagen membrane only (M), 3) bone graft group (B), 4) bone graft with membrane group (B+M). Animals were sacrificed and samples were harvested at 2 weeks (n=5) and 8 weeks (n=5). Histologic sections were prepared and histomorphometric analysis was performed.Result: Histologic results showed well adaptation of the non-cross-linked membrane on each defect and normal healing response at 2 weeks. At 8 weeks, the membranes were partially biodegraded. Histomorphometrically, B and B+M group showed the significantly greater total augmented area (B+M group, 10.44±1.49, P=0.016; B group, 9.13±0.53, P=0.032) and new bone formation (B+M group, 2.89±0.93, P=0.008; B group, 2.85±1.15, P=0.008) compared to control group. Collapsing of the central portion of the membrane, membrane group showed greater value in new bone formation at 8 weeks (1.78±0.68, P=0.032). @*Conclusion@#Within the limitations of this study, the non-cross-linked collagen membrane fabricated using the improved decellularized method was shown to be effective for the regeneration of calvarial bone defects. In addition, prolonged barrier function might be provided using this collagen membrane.
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Purpose@#(i) To evaluate the biologic properties of a bi-layered 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride-cross-linked collagen membrane (CCM) In Vitro. (ii) To assess the efficacy of CCM for localized bone regeneration In Vivo. @*Materials and Methods@#Biodegradation of CCM compared to a native collagen membrane (NCM) was assessed In Vitro. In Vivo, twelve male New Zealand White rabbits were used. Four calvarial, circular defects (diameter 8 mm) were created in each animal. The sites were randomly allocated to i) CCM+biphasic calcium phosphate (BCP) (CCM-BCP group), ii) CCM alone (CCM), iii) BCP alone (BCP) and, iv) negative control (control). Animals were sacrificed at 2 (n=6) and 8 weeks (n=6). Outcome measures included: micro-computed tomography (μCT) analysis (total augmented volume [TAV], new bone volume) and histomorphometry (total augmented area [TAA], newly formed bone, remaining membrane thickness [RMT]).Result: CCM was more resistant to degradation than NCM. μCT analysis showed CCM-BCP (196.43±25.30 mm 3 ) and BCP (206.23±39.13 mm 3 ) groups had significantly (P<0.01) larger TAV than the control (149.72±12.28 mm 3 ) after 8 weeks. Histomorphometrically, CCM-BCP group (17.75±5.97 mm 2 ) had significantly (P<0.01) greater TAA compared to the CCM group (7.74±2.25 mm 2 ) and the control (8.13±1.81 mm 2 ) after 8 weeks. After 8 weeks, RMT was reduced by 67%. @*Conclusion@#CCM can be a favorable choice of barrier membrane when performing guided bone regeneration (GBR) in localized bone defects. CCM has better resistance to degradation than the natural collagen membrane, In Vitro. In Vivo, CCM provides an advantageous integration of prolonged barrier function and biocompatibility for GBR.
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Objective@#To quantitatively analyze the effect of nicotine on orthodontic tooth movement (OTM) and bone remodeling in rats using micro-computed tomography and tartrate-resistant acid phosphatase immunostaining. @*Methods@#Thirty-nine adult male Sprague–Dawley rats were randomized into three groups: group A, 0.5 mL normal saline (n = 9, 3 per 3, 7, and 14 days); group B, 0.83 mg/kg nicotine (n = 15, 5 per 3, 7, and 14 days); and group C, 1.67 mg/kg nicotine (n = 15, 5 per 3, 7, and 14 days). Each animal received daily intraperitoneal injections of nicotine/saline from the day of insertion of identical 30-g orthodontic force delivery systems. A 5-mm nickel-titanium closed-coil spring was applied between the left maxillary first molar (M1) and the two splinted incisors. The rate of OTM and volumetric bone changes were measured using micro-computed tomography. Osteoclasts were counted on the mesial alveolar bone surface of the distobuccal root of M1. Six dependent outcome variables, including the intermolar distance, bone volume fraction, bone mineral density, trabecular thickness, trabecular volume, and osteoclast number, were summarized using simple descriptive statistics. Nonparametric Kruskal–Wallis tests were used to evaluate differences among groups at 3, 7, and 14 days of OTM. @*Results@#All six dependent outcome variables showed no statistically significant among group-differences at 3, 7, and 14 days. @*Conclusions@#The findings of this study suggest that nicotine does not affect OTM and bone remodeling, although fluctuations during the different stages of OTM in the nicotine groups should be elucidated in further prospective studies.
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Objective@#To quantitatively analyze the effect of nicotine on orthodontic tooth movement (OTM) and bone remodeling in rats using micro-computed tomography and tartrate-resistant acid phosphatase immunostaining. @*Methods@#Thirty-nine adult male Sprague–Dawley rats were randomized into three groups: group A, 0.5 mL normal saline (n = 9, 3 per 3, 7, and 14 days); group B, 0.83 mg/kg nicotine (n = 15, 5 per 3, 7, and 14 days); and group C, 1.67 mg/kg nicotine (n = 15, 5 per 3, 7, and 14 days). Each animal received daily intraperitoneal injections of nicotine/saline from the day of insertion of identical 30-g orthodontic force delivery systems. A 5-mm nickel-titanium closed-coil spring was applied between the left maxillary first molar (M1) and the two splinted incisors. The rate of OTM and volumetric bone changes were measured using micro-computed tomography. Osteoclasts were counted on the mesial alveolar bone surface of the distobuccal root of M1. Six dependent outcome variables, including the intermolar distance, bone volume fraction, bone mineral density, trabecular thickness, trabecular volume, and osteoclast number, were summarized using simple descriptive statistics. Nonparametric Kruskal–Wallis tests were used to evaluate differences among groups at 3, 7, and 14 days of OTM. @*Results@#All six dependent outcome variables showed no statistically significant among group-differences at 3, 7, and 14 days. @*Conclusions@#The findings of this study suggest that nicotine does not affect OTM and bone remodeling, although fluctuations during the different stages of OTM in the nicotine groups should be elucidated in further prospective studies.
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Irritation fibroma is a reactive hyperplastic lesion caused by chronic stimuli with low intensity in the oral cavity. Irritation fibroma is common in middle-aged females but it may also occur at any age and sex. Clinical characteristics of irritation fibroma are similar to other reactive lesions or benign tumors, therefore, histological examination is essential to make an accurate diagnosis. This case report presents two cases of irritation fibroma occurred on the gingiva in young males. Two male patients in their 20s and 30s of age visited the clinic for the evaluation and treatment of painless gingival overgrowth in the anterior region. Clinically, the lesions were well-defined and firm, with similar color and texture to the adjacent normal gingiva. Excisional biopsy under local anesthesia was conducted with a scalpel, and the lesions were completely removed. Histopathologically, connective tissue consisting of dense collagen bundles, proliferation of fibroblasts and minor infiltrated inflammatory cells were observed. Based on the clinical and histopathological findings, the diagnosis of irritation fibroma was confirmed in both cases.
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PURPOSE: To overcome several drawbacks of chemically-crosslinked collagen membranes, modification processes such as ultraviolet (UV) crosslinking and the addition of biphasic calcium phosphate (BCP) to collagen membranes have been introduced. This study evaluated the efficacy and biocompatibility of BCP-supplemented UV-crosslinked collagen membrane for guided bone regeneration (GBR) in a rabbit calvarial model.METHODS: Four circular bone defects (diameter, 8 mm) were created in the calvarium of 10 rabbits. Each defect was randomly allocated to one of the following groups: 1) the sham control group (spontaneous healing); 2) the M group (defect coverage with a BCP-supplemented UV-crosslinked collagen membrane and no graft material); 3) the BG (defects filled with BCP particles without membrane coverage); and 4) the BG+M group (defects filled with BCP particles and covered with a BCP-supplemented UV-crosslinked collagen membrane in a conventional GBR procedure). At 2 and 8 weeks, rabbits were sacrificed, and experimental defects were investigated histologically and by micro-computed tomography (micro-CT).RESULTS: In both micro-CT and histometric analyses, the BG and BG+M groups at both 2 and 8 weeks showed significantly higher new bone formation than the control group. On micro-CT, the new bone volume of the BG+M group (48.39±5.47 mm3) was larger than that of the BG group (38.71±2.24 mm3, P=0.032) at 8 weeks. Histologically, greater new bone area was observed in the BG+M group than in the BG or M groups. BCP-supplemented UV-crosslinked collagen membrane did not cause an abnormal cellular reaction and was stable until 8 weeks.CONCLUSIONS: Enhanced new bone formation in GBR can be achieved by simultaneously using bone graft material and a BCP-supplemented UV-crosslinked collagen membrane, which showed high biocompatibility and resistance to degradation, making it a biocompatible alternative to chemically-crosslinked collagen membranes.
Subject(s)
Animals , Rabbits , Absorbable Implants , Bone Regeneration , Calcium , Collagen , Membranes , Osteogenesis , Skull , Transplants , Ultraviolet RaysABSTRACT
Purpose@#This study was conducted to analyze specific RNA expression profiles in gingival tissue and saliva samples in periodontitis patients and healthy individuals, and to determine their correlations in light of the potential use of microarray-based analyses of saliva samples as a periodontal monitoring tool. @*Methods@#Gingival tissue biopsies and saliva samples from 22 patients (12 with severe periodontitis and 10 with a healthy periodontium) were analyzed using transcriptomic microarray analysis. Differential gene expression was assessed, and pathway and clustering analyses were conducted for the samples. The correlations between the results for the gingival tissue and saliva samples were analyzed at both the gene and pathway levels. @*Results@#There were 621 differentially expressed genes (DEGs; 320 upregulated and 301 downregulated) in the gingival tissue samples of the periodontitis group, and 154 DEGs (44 upregulated and 110 downregulated) in the saliva samples. Nine of these genes overlapped between the sample types. The periodontitis patients formed a distinct cluster group based on gene expression profiles for both the tissue and saliva samples. Database for Annotation, Visualization and Integrated Discovery analysis revealed 159 enriched pathways from the tissue samples of the periodontitis patients, as well as 110 enriched pathways In the saliva samples. Thirty-four pathways overlapped between the sample types. @*Conclusions@#The present results indicate the possibility of using the salivary transcriptome to distinguish periodontitis patients from healthy individuals. Further work is required to enhance the extraction of available RNA from saliva samples.
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Purpose@#This study was conducted to assess the efficacy of prophylactic gingival grafting in the mandibular anterior labial area for preventing orthodontically induced gingival recession. @*Methods@#Eight mongrel dogs received gingival graft surgery at the first (I1) and third (I3) mandibular incisors on both sides based on the following group allocation: AT group (autogenous connective tissue graft on I1), AT-control group (contralateral side in the AT group), CM group (xenogeneic cross-linked collagen matrix graft on I3) and CM-control group (contralateral side in the CM group). At 4 weeks after surgery, 6 incisors were splinted and proclined for 4 weeks, followed by 16 weeks of retention. At 24 weeks after surgery, casts were made and compared with those made before surgery, and radiographic and histomorphometric analyses were performed. @*Results@#Despite the proclination of the incisal tip (by approximately 3 mm), labial gingival recession did not occur. The labial gingiva was thicker in the AT group (1.85±0.50 mm vs.1.76±0.45 mm, P>0.05) and CM group (1.90±0.33 mm vs. 1.79±0.20 mm, P>0.05) than in their respective control groups. @*Conclusions@#The level of the labial gingival margin did not change following labial proclination of incisors in dogs. Both the AT and CM groups showed enhanced gingival thickness.
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Purpose@#This study was conducted to analyze specific RNA expression profiles in gingival tissue and saliva samples in periodontitis patients and healthy individuals, and to determine their correlations in light of the potential use of microarray-based analyses of saliva samples as a periodontal monitoring tool. @*Methods@#Gingival tissue biopsies and saliva samples from 22 patients (12 with severe periodontitis and 10 with a healthy periodontium) were analyzed using transcriptomic microarray analysis. Differential gene expression was assessed, and pathway and clustering analyses were conducted for the samples. The correlations between the results for the gingival tissue and saliva samples were analyzed at both the gene and pathway levels. @*Results@#There were 621 differentially expressed genes (DEGs; 320 upregulated and 301 downregulated) in the gingival tissue samples of the periodontitis group, and 154 DEGs (44 upregulated and 110 downregulated) in the saliva samples. Nine of these genes overlapped between the sample types. The periodontitis patients formed a distinct cluster group based on gene expression profiles for both the tissue and saliva samples. Database for Annotation, Visualization and Integrated Discovery analysis revealed 159 enriched pathways from the tissue samples of the periodontitis patients, as well as 110 enriched pathways In the saliva samples. Thirty-four pathways overlapped between the sample types. @*Conclusions@#The present results indicate the possibility of using the salivary transcriptome to distinguish periodontitis patients from healthy individuals. Further work is required to enhance the extraction of available RNA from saliva samples.
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Purpose@#This study was conducted to assess the efficacy of prophylactic gingival grafting in the mandibular anterior labial area for preventing orthodontically induced gingival recession. @*Methods@#Eight mongrel dogs received gingival graft surgery at the first (I1) and third (I3) mandibular incisors on both sides based on the following group allocation: AT group (autogenous connective tissue graft on I1), AT-control group (contralateral side in the AT group), CM group (xenogeneic cross-linked collagen matrix graft on I3) and CM-control group (contralateral side in the CM group). At 4 weeks after surgery, 6 incisors were splinted and proclined for 4 weeks, followed by 16 weeks of retention. At 24 weeks after surgery, casts were made and compared with those made before surgery, and radiographic and histomorphometric analyses were performed. @*Results@#Despite the proclination of the incisal tip (by approximately 3 mm), labial gingival recession did not occur. The labial gingiva was thicker in the AT group (1.85±0.50 mm vs.1.76±0.45 mm, P>0.05) and CM group (1.90±0.33 mm vs. 1.79±0.20 mm, P>0.05) than in their respective control groups. @*Conclusions@#The level of the labial gingival margin did not change following labial proclination of incisors in dogs. Both the AT and CM groups showed enhanced gingival thickness.
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PURPOSE: The purpose of this study was to evaluate the effectiveness of conventional sandblasted, large-grit, acid-etched (SLA) surface coated with a pH buffering solution based on surface wettability, blood protein adhesion, osteoblast affinity, and platelet adhesion and activation.METHODS: Titanium discs and implants with conventional SLA surface (SA), SLA surface in an aqueous calcium chloride solution (CA), and SLA surface with a pH buffering agent (SOI) were prepared. The wetting velocity was measured by the number of threads wetted by blood over an interval of time. Serum albumin adsorption was tested using the bicinchoninic acid assay and by measuring fluorescence intensity. Osteoblast activity assays (osteoblast adhesion, proliferation, differentiation, mineralization, and migration) were also performed, and platelet adhesion and activation assays were conducted.RESULTS: In both the wetting velocity test and the serum albumin adsorption assay, the SOI surface displayed a significantly higher wetting velocity than the SA surface (P=0.000 and P=0.000, respectively). In the osteoblast adhesion, proliferation, differentiation, and mineralization tests, the mean values for SOI were all higher than those for SA and CA. On the osteoblast migration, platelet adhesion, and activation tests, SOI also showed significantly higher values than SA (P=0.040, P=0.000, and P=0.000, respectively).CONCLUSIONS: SOI exhibited higher hydrophilicity and affinity for proteins, cells, and platelets than SA. Within the limits of this study, it may be concluded that coating an implant with a pH buffering agent can induce the attachment of platelets, proteins, and cells to the implant surface. Further studies should be conducted to directly compare SOI with other conventional surfaces with regard to its safety and effectiveness in clinical settings.
Subject(s)
Adsorption , Blood Platelets , Calcium Chloride , Coated Materials, Biocompatible , Dental Implants , Fluorescence , Hydrogen-Ion Concentration , Hydrophobic and Hydrophilic Interactions , Immunoassay , In Vitro Techniques , Miners , Osteoblasts , Serum Albumin , Surface Properties , Titanium , WettabilityABSTRACT
PURPOSE: To histologically characterize periodontal healing at 8 weeks in surgically created dehiscence defects in beagle dogs that received a collagen matrix with periodontal ligament (PDL) progenitor cells. METHODS: The bilateral maxillary premolars and first molars in 6 animals were used. Standardized experimental dehiscence defects were made on the buccal side of 3 premolars, and primary culturing of PDL progenitor cells was performed on the molars. Collagen matrix was used as a scaffold and a delivery system for PDL progenitor cells. The experimental sites were grafted with collagen matrix (COL), PDL progenitor cells with collagen matrix (COL/CELL), or left without any material (CTL). Histologic and histomorphometric analyses were performed after 8 weeks. RESULTS: The defect height from the cementoenamel junction to the most apical point of cementum removal did not significantly differ across the CTL, COL, and COL/CELL groups, at 4.57±0.28, 4.56±0.41, and 4.64±0.27 mm (mean ± standard deviation), respectively; the corresponding values for epithelial adhesion were 1.41±0.51, 0.85±0.29, and 0.30±0.41 mm (P<0.05), the heights of new bone regeneration were 1.32±0.44, 1.65±0.52, and 1.93±0.61 mm (P<0.05), and the cementum regeneration values were 1.15±0.42, 1.81±0.46, and 2.57±0.56 mm (P<0.05). There was significantly more new bone formation in the COL/CELL group than in the CTL group, and new cementum length was also significantly higher in the COL/CELL group. However, there were no significant differences in the width of new cementum among the groups. CONCLUSIONS: PDL progenitor cells carried by a synthetic collagen matrix may enhance periodontal regeneration, including cementum and new bone formation.
Subject(s)
Animals , Dogs , Bicuspid , Bone Regeneration , Collagen , Dental Cementum , Molar , Osteogenesis , Periodontal Ligament , Regeneration , Stem Cells , Tooth Cervix , TransplantsABSTRACT
The primary aim of this systematic review was to assess the evidence on periodontal disease progression after treatment in patients receiving supportive periodontal therapy (SPT) and to identify predictors of clinical attachment level (CAL) loss. A protocol was developed to answer the following focused question: In adult patients treated for periodontitis, what is the disease progression in terms of CAL loss after surgical or non-surgical treatment? Randomized controlled clinical trials, prospective cohort studies, and longitudinal observational human studies with a minimum of 5 years of follow-up after surgical or non-surgical treatment that reported CAL and probing depth changes were selected. Seventeen publications reporting data from 14 investigations were included. Data from 964 patients with a follow-up range of 5–15 years was evaluated. When the CAL at the latest follow-up was compared to the CAL after active periodontal therapy, 10 of the included studies reported an overall mean CAL loss of ≤0.5 mm, 3 studies reported a mean CAL loss of 0.5–1 mm, and 4 studies reported a mean CAL loss of >1 mm. Based on 7 publications, the percentage of sites showing a CAL loss of ≥2 mm varied from 3% to 20%, and a high percentage of sites with CAL loss was associated with poor oral hygiene, smoking, and poor compliance with SPT. The outcomes after periodontal therapy remained stable over time. Disease progression occurred in a reduced number of sites and patients, mostly associated with poor oral hygiene, poor compliance with SPT, and smoking.
Subject(s)
Adult , Humans , Cohort Studies , Compliance , Disease Progression , Follow-Up Studies , Oral Hygiene , Periodontal Attachment Loss , Periodontal Diseases , Periodontitis , Prospective Studies , Smoke , SmokingABSTRACT
PURPOSE: This study was designed to observe the resorption pattern of biphasic calcium phosphate (BCP) used for maxillary sinus augmentation over a 3- to 6-year healing period, and to investigate factors affecting the resorption of BCP. METHODS: A total of 47 implants placed in 27 sinuses of 22 patients were investigated. All patients had residual bone height less than 5 mm at baseline. The modified Caldwell-Luc approach was used to elevate the maxillary sinus membrane, and the sinus cavity was filled with BCP (70% hydroxyapatite and 30% β-tricalcium phosphate). Implant placement was done simultaneously or in a staged manner. Serial radiographic analysis was performed up to 6 years postoperatively. RESULTS: During the follow-up period, no implant loss was reported. The mean reduced height of the augmented sinus (RHO) was 0.27±1.08 mm at 36 months, and 0.89±1.39 mm at 72 months postoperatively. Large amounts of graft material (P=0.021) and a long healing period (P=0.035) significantly influenced the amount of RHO. In particular, there was a significant relationship between a healing period longer than 40 months and RHO. CONCLUSIONS: BCP can achieve proper dimensional stability with minimal reduction of the graft height in a 3- to 6-year healing period after maxillary sinus augmentation. The healing period and the amount of graft material influenced the resorption of BCP.
Subject(s)
Humans , Bone Substitutes , Calcium , Dental Implants , Durapatite , Follow-Up Studies , Maxillary Sinus , Membranes , Sinus Floor Augmentation , TransplantsABSTRACT
PURPOSE: The aim of the present study was to evaluate the biocompatibility and barrier function of mussel adhesive protein (MAP)-loaded collagen membranes in guided bone regeneration (GBR). METHODS: Eight male New Zealand white rabbits were used. Four circular defects (diameter: 8 mm) were created in the calvarium of each animal. The defects were randomly assigned to 1) a negative control group, 2) a cyanoacrylate (CA)-loaded collagen membrane group (the CA group), 3) a MAP-loaded collagen membrane group (the MAP group), and 4) a group that received a polycaprolactone block with MAP-loaded collagen membrane (the MAP-PCL group). Specimens were harvested at 2 weeks (n=4) and 8 weeks (n=4) postoperatively for observational histology and histometric analysis. RESULTS: In the histologic analysis, MAP was completely absorbed without any byproducts. In contrast, some of the CA adhesive remained, showing an inflammatory reaction, at 8 weeks. In the MAP-PCL group, the MAP-loaded collagen membranes served as a barrier membrane despite their fast degradation in GBR. No significant difference was found in the amount of new bone between the MAP-PCL and MAP groups (1.82±0.86 mm2 and 2.60±0.65 mm2, respectively). CONCLUSIONS: The MAP-loaded collagen membrane functioned efficiently in this rabbit calvarial GBR model, with excellent biocompatibility. Further research is needed to assess clinical applications in defect types that are more challenging for GBR than those used in the current model.
Subject(s)
Animals , Humans , Male , Rabbits , Adhesives , Biomimetics , Bivalvia , Bone Regeneration , Collagen , Cyanoacrylates , Membranes , Mytilus edulis , Polymers , Skull , Tissue AdhesivesABSTRACT
PURPOSE: The purpose of this study was to assess the adhesiveness and cytotoxicity of 3, 4-dihydroxyphenylalanine (DOPA), and to evaluate the role of collagen membrane with DOPA in the guided bone regeneration. MATERIALS AND METHODS: Peel resistance and cell cytotoxicity test were performed. Four defect types in nine rabbit calvaria were randomly allocated: i) control, ii) membrane, iii) deproteinized porcine bone mineral (DPBM) covered by membrane with DOPA, and iv) DPBM covered by membrane with cyanoacrylate. Animals were sacrificed at 2 (n=4) and 8 weeks (n=5) for microcomputed tomography and histomorphometric analysis. DOPA showed low peel resistance but high cell viability. RESULT: Cyanoacrylate and DOPA groups showed significantly higher mineralized tissue volume (MTV) compared to control and membrane groups at 2 weeks (P < 0.05). At 8 weeks, DOPA group showed the highest MTV. Significantly higher new bone area was found in DOPA group at 8 weeks (P < 0.05). Bone formation increased from 2 to 8 weeks in DOPA group (P < 0.05). CONCLUSION: DOPA showed high cell viability and in vivo study revealed predictable performance in bone regeneration.
Subject(s)
Animals , Adhesiveness , Adhesives , Bone Regeneration , Cell Survival , Collagen , Cyanoacrylates , Dihydroxyphenylalanine , Membranes , Miners , Osteogenesis , Skull , X-Ray MicrotomographyABSTRACT
PURPOSE: Surface treatment with pH buffering agent has been developed to achieve higher and faster osseointegration. The aim of this study was to evaluate its influence by measuring removal torque and analyzing histological characteristics. MATERIALS AND METHODS: Titanium implants with following surfaces were used in this study: sand-blasted acid-etched (SA) surface (SA group as control I group), SA surface in calcium chloride aqueous solution (CA group as control II group) and SA surface coated with pH buffering agent (pH group as test group). Removal torque test after 2 weeks and bone-to-implant contact and bone area analyses at 2 and 4 weeks were performed. RESULT: The rotational torque values at 2 weeks were significantly higher in pH group (107.5±6.2 Ncm, P < 0.05). The mean values of bone-to-implant contact at 2 and 4 weeks were both higher in pH group (93.0%±6.4% at 2 weeks, 88.6%±5.5% at 4 weeks) than in SA group (49.7%±9.7% at 2 weeks, 47.3%±20.1% at 4 weeks) and CA group (73.7%±12.4% at 2 weeks, 72.5%±10.9% at 4 weeks) with significances (P < 0.05). The means of bone area showed significantly higher numbers in pH group (39.5%±11.3% at 2 weeks, 71.9%±10.9% at 4 weeks, P < 0.05). CONCLUSION: Our findings demonstrated that surface modification with pH buffering agent improved early osseointegration with superior biomechanical property.
Subject(s)
Calcium Chloride , Dental Implants , Hydrogen-Ion Concentration , Hydrophobic and Hydrophilic Interactions , Osseointegration , Statistics as Topic , Surface Properties , Titanium , TorqueABSTRACT
PURPOSE: The aim of this study was to determine the effect of recombinant human bone morphogenetic protein-2 (rhBMP-2)-loaded synthetic bone substitute on implants that were simultaneously placed with sinus augmentation in rabbits. METHODS: In this study, a circular access window was prepared in the maxillary sinus of rabbits (n=5) for a bone graft around an implant (Ø 3×6 mm) that was simultaneously placed anterior to the window. Synthetic bone substitute loaded with rhBMP-2 was placed on one side of the sinus to form the experimental group, and saline-soaked synthetic bone substitute was placed on the other side of the sinus to form the control group. After 4 weeks, sections were obtained for analysis by micro-computed tomography and histology. RESULTS: Volumetric analysis showed that the median amount of newly formed bone was significantly greater in the BMP group than in the control group (51.6 mm3 and 46.6 mm3, respectively; P=0.019). In the histometric analysis, the osseointegration height was also significantly greater in the BMP group at the medial surface of the implant (5.2 mm and 4.3 mm, respectively; P=0.037). CONCLUSIONS: In conclusion, an implant simultaneously placed with sinus augmentation using rhBMP-2-loaded synthetic bone substitute can be successfully osseointegrated, even when only a limited bone height is available during the early stage of healing.
Subject(s)
Humans , Rabbits , Bone Substitutes , Collagen , Dental Implants , Maxillary Sinus , Osseointegration , Sinus Floor Augmentation , TransplantsABSTRACT
The aim of this narrative review is to describe treatment options for the posterior regions of the mandible and the maxilla, comparing short implants vs. longer implants in an augmented bone. The dental literature was screened for treatment options enabling the placement of dental implants in posterior sites with a reduced vertical bone height in the maxilla and the mandible. Short dental implants have been increasingly used recently, providing a number of advantages including reduced patient morbidity, shorter treatment time, and lower costs. In the posterior maxilla, sinus elevation procedures were for long considered to be the gold standard using various bone substitute materials and rendering high implant survival rates. More recently, implants were even placed without any further use of bone substitute materials, but the long-term outcomes have yet to be documented. Vertical bone augmentation procedures in the mandible require a relatively high level of surgical skill and allow the placement of standard-length dental implants by the use of autogenous bone blocks. Both treatment options, short dental implants, and standard-length implants in combination with vertical bone augmentation procedures, appear to result in predictable outcomes in terms of implant survival rates. According to recent clinical studies comparing the therapeutic options of short implants vs. long implants in augmented bone, the use of short dental implants leads to a number of advantages for the patients and the clinician.