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This case report describes the treatment of peri-implantitis lesions through a minimally invasive surgical procedure using a peri-implant excisional procedure and access surgery (PEAS). The prosthesis was disconnected, and the peri-implant granulation tissue removed after a peri-implant circular incision. Chemical debridement with hydrogen peroxide on a cotton ball and then mechanical debridement with a rotary round titanium brush and tufted brush with titanium bristles were conducted. The surgical intervention was effective in arresting the peri-implantitis. No further radiographic bone loss was observed over the 2-year follow-up period. This technique effectively cleans the contaminated implant surface, minimizes surgical morbidity, and allows for prosthesis delivery on the day of surgery. However, further studies with a larger sample size are needed to identify the reliability and validity of this novel technique.

We previously suggested an ovariectomy (OVX)-induced osteoporotic rat model showing an impaired alveolar bone defect healing. This study aimed to evaluate and compare the effects of recombinant human bone morphogenetic protein-2 (rhBMP-2) and recombinant human platelet-derived growth factor-BB (rhPDGF-BB) on alveolar bone defect healing in OVX-induced osteoporotic rats. A total of forty-one female rats were divided into four groups: a collagen group (n=10), a PDGF-BB group (n=11), a BMP-2 group (n=10), and a control group (n=10). Four months after OVX, alveolar bone drill-hole defects were created and grafted with collagen gel, rhPDGF-BB/collagen gel, or rhBMP-2/collagen gel. The defects in the control group were not grafted with any material. Defect healing was evaluated by histological, histomorphometric, and microcomputed tomographic (micro-CT) analyses at 2 and 4 weeks. According to the micro-CT analysis, the BMP-2 group exhibited the greatest bone volume fraction among all groups, while the PDGF-BB group did not show significant differences compared with the collagen group. The histomorphometric analysis showed a significantly larger amount of new bone area in the BMP-2 group than in the control and collagen groups at 4 weeks; however, the PDGF-BB group did not reach significant superiority compared with the other groups. Alveolar bone regeneration was significantly enhanced by the local use of rhBMP-2/collagen gel compared with the use of rhPDGF-BB/collagen gel in OVX-induced osteoporotic rats. A treatment modality using rhBMP-2 may be a promising approach to promote alveolar bone regeneration in patients suffering from postmenopausal osteoporosis.

The purpose of this study was to evaluate and compare the healing patterns of 2-mm and 4-mm proximal infrabony defects adjacent to dental implants in canine mandibles.Four male beagles were used. Two groups were created: a 2-mm group (n=4) and a 4-mm group (n=4) depending on the horizontal dimension of proximal infrabony defects adjacent to implants. Bone healing patterns between the 2 groups were evaluated and compared at 8 and 16 weeks using radiographic, histological, histomorphometric, and fluorescent labelling analyses.According to microcomputed tomography, the median bone volume fraction, bone mineral density, and the percentage of radiographic distance from the defect bottom to the most coronal bone-to-implant contact (radio-mcBIC) were 32.9%, 0.6 g/cmThe proximal defects that measured 2 mm and 4 mm showed similar healing patterns at 8 and 16 weeks, and the top of bone formation in the defects was substantially limited to a maximum of 1.6 mm below the implant shoulder in both groups.

3D printing technology has been gradually applied to various areas. In the present study, 3D-printed implants were fabricated with direct metal laser sintering technique for a dental single root with titanium. The 3D implants were allocated into following groups: not treated (3D-None), sandblasted with a large grit and acid-etched (3D-SLA), and target-ion-induced plasma-sputtered surface (3D-TIPS). Two holes were drilled in each tibia of rabbit, and the three groups of implants were randomly placed with a mallet. Rabbits were sacrificed at two, four, and twelve weeks after the surgery. Histologic and histomorphometric analyses were performed for the evaluation of mineralized bone-to-implant contact (mBIC), osteoid-to-implant contact (OIC), total bone-to-implant contact (tBIC), mineralized bone area fraction occupancy (mBAFO), osteoid area fraction occupancy (OAFO), and total bone area fraction occupancy (tBAFO) in the inner and outer areas of lattice structure. At two weeks, 3D-TIPS showed significantly higher inner and outer tBIC and inner tBAFO compared with other groups. At four weeks, 3D-TIPS showed significantly higher outer OIC than 3D-SLA, but there were no significant differences in other variables. At twelve weeks, there were no significant differences. The surface treatment with TIPS in 3D-printed implants could enhance the osseointegration process in the rabbit tibia model, meaning that earlier osseointegration could be achieved.

The association between oral squamous cell carcinoma (OSCC) and periodontitis in large hospital cases with cohort controls has yet to be evaluated. The aim of this study was to investigate the association of periodontitis with OSCC across tumor location and tumor-node-metastasis (TNM) stage among Koreans ( N = 424). OSCC cases ( n = 146) were recruited from Seoul National University Dental Hospital and matched by age, sex, and smoking to controls ( n = 278) from the Yangpyeong health and periodontal cohort in Korea. OSCC was diagnosed through biopsy and radiographs, including computed tomography and magnetic resonance imaging. Tumor location and TNM stage were classified after the surgery. Periodontitis was defined by alveolar bone loss with panoramic radiographs following the guidelines of the Fifth European Workshop in Periodontology. Alcohol intake, education, physical activity, obesity by body mass index, hypertension by blood pressure, diabetes by plasma glucose, and hypercholesterolemia by plasma cholesterol were considered as confounders. Information about age, sex, smoking, alcohol intake, education, and physical activity was obtained through interview; body mass index and blood pressure, through physical examination; and preoperative glucose and cholesterol, through laboratory tests. Bivariate analysis was applied with Fisher’s exact chi-square test. Multivariable conditional logistic regression models were applied to evaluate the adjusted association of periodontitis with OSCC after controlling for confounders. Subgroup analyses were explored by OSCC and periodontitis. Participants with periodontitis were 3.7 times more likely to have OSCC (adjusted odds ratio [aOR] = 3.66, 95% CI = 1.46 to 9.23) than participants without periodontitis. The differences in periodontitis were not statistically significant across TNM stages of OSCC ( P > 0.05) and its location ( P > 0.05). The link was highlighted among males (aOR = 6.55), elders aged >60 y (aOR = 4.98), and those with more tooth loss (aOR = 9.99). Our data showed that periodontitis was independently associated with OSCC. Thus, the risk of OSCC could be modulated by reducing periodontitis.

Background This experimental study aims to evaluate the effect of hyaluronic acid on healing of infected extraction sockets compared with recombinant human bone morphogenetic protein-2 (rhBMP-2). Methods Both third and fourth mandibular premolars of six beagle dogs were hemisected, and the distal roots were extracted at baseline. Subsequently, combined endodontic-periodontic lesions were induced at the remaining mesial roots. After 4 months, the mesial roots on both sides of the mandible were removed. Four sockets per dog were randomly allocated to four groups: Group 1, Control; Group 2, only absorbable collagen sponge (ACS: carrier); Group 3, 1% hyaluronic acid (HA) gel + ACS; and Group 4, rhBMP-2 + ACS. After 3 months of healing, the dogs were euthanized for microcomputed tomography and histologic analysis. Results After the lesion induction period (4 months), communication between the periodontal lesion and endodontic periapical lesion was observed at all remaining mesial roots. Alveolar bone overgrowth was observed in groups 3 and 4, but bone volume density was not significantly different among all groups. At the crestal portion, mineralization, and osteocalcin expression were higher in groups 3 and 4 than in groups 1 and 2. Conclusion Treatment with HA can promote bone formation and improve the wound healing rate comparable to rhBMP-2 in infected extraction sockets.

Bone quality as well as its quantity at the implant interface is responsible for determining stability of the implant system. The objective of this study is to examine the nanoindentation based elastic modulus (E) at different bone regions adjacent to titanium dental implants with guided bone regeneration (GBR) treated with DBM and BMP-2 during different post-implantation periods. Six adult male beagle dogs were used to create circumferential defects with buccal bone removal at each implantation site of mandibles. The implant systems were randomly assigned to only GBR (control), GBR with demineralized bone matrix (DBM), and GBR with DBM + recombinant human bone morphogenetic protein-2 (rhBMP-2) (BMP) groups. Three animals were sacrificed at each 4 and 8 weeks of post-implantation healing periods. Following buccolingual dissection, the E values were assessed at the defects (Defect), interfacial bone tissue adjacent to the implant (Interface), and pre-existing bone tissue away from the implant (Pre-existing). The E values of BMP group had significantly higher than control and DBM groups for interface and defect regions at 4 weeks of post-implantation period and for the defect region at 8 weeks (p 0.043). DBM group had higher E values than control group only for the defect region at 4 weeks (p 0.001). The current results indicate that treatment of rhBMP-2 with GBR accelerates bone tissue mineralization for longer healing period because the GBR likely facilitates a microenvironment to provide more metabolites with open space of the defect region surrounding the implant.

Purpose In this study, we aimed to evaluate the clinical validity of the modified tunneling technique using minimal soft tissue harvesting and volume-stable collagen matrix in the anterior mandible. Methods In total, 27 anterior mandibular teeth and palatal donor sites in 17 patients with ≥1 mm of gingival recession (GR) were analyzed before and after root coverage. For the recipient sites, vertical vestibular incisions were made in the interdental area and a subperiosteal tunnel was created with an elevator. After both sides of the marginal gingiva were tied to one another, a prepared connective tissue graft and volume-stable collagen matrix were inserted through the vestibular vertical incision and were fixed with resorbable suture material. The root coverage results of the recipient site were measured at baseline (T0), 3 weeks (T3), 12 weeks (T12), and the latest visit (Tl). For palatal donor sites, a free gingival graft from a pre-decided area avoiding the main trunk of the greater palatine artery was harvested using a prefabricated surgical template at a depth of 2 mm after de-epithelization using a rotating bur. In each patient, the clinical and volumetric changes at the donor sites between T0 and T3 were measured. Results During an average follow-up of 14.5 months, teeth with denuded root lengths of 1–3 mm (n=12), 3–6 mm (n=11), and >6 mm (n=2) achieved root coverage of 97.01%±7.65%, 86.70%±5.66%, and 82.53%±1.39%, respectively. Miller classification I (n=12), II (n=10), and III (n=3) teeth showed mean coverage rates of 97.01%±7.65%, 86.91%±5.90%, and 83.19%±1.62%, respectively. At the donor sites, an average defect depth of 1.41 mm (70.5%) recovered in 3 weeks, and the wounds were epithelized completely in all cases. Conclusions The modified tunneling technique in this study is a promising treatment modality for overcoming GR in the anterior mandible., Graphical Abstract

Background The aim of this study was to evaluate the efficacy of deproteinized bovine bone mineral with 10% collagen (DBBM-C) soaked with hyaluronic acid (HA) for ridge preservation in compromised extraction sockets. Methods Bilateral third, fourth premolars and first molar were hemisected, distal roots were extracted, and then combined endodontic periodontal lesion was induced in the remaining mesial roots. After 4 months, the mesial roots were extracted and the following four treatments were randomly performed: Absorbable collagen sponge (ACS), ACS soaked with HA (ACS+HA), Ridge preservation with DBBM-C covered with a collagen membrane (RP), Ridge preservation with DBBM-C mixed with HA and covered with a collagen membrane (RP+HA). Animals were sacrificed at 1 and 3 months following treatment. Ridge dimensional changes and bone formation were examined using microcomputed tomography, histology, and histomorphometry. Results At 1 month, ridge width was significantly higher in the RP and RP+HA groups than in the ACS and ACS+HA groups, while the highest proportion of mineralized bone was observed in ACS+HA group. At 3 months, ridge width remained significantly higher in the RP and RP+HA groups than in the ACS and ACS+HA groups. ACS+HA and RP+HA treatments featured the highest proportion of mineralized bone and bone volume density compared to the other groups. No statistical difference was observed between ACS+HA and RP+HA treatments. Conclusions Ridge preservation with the mixture DBBM-C/HA prevented dimensional shrinkage and improved bone formation in compromised extraction sockets at 1 and 3 months. This article is protected by copyright. All rights reserved, One sentence summary. The mixture of hyaluronic acid and deproteinized bovine bone mineral with 10% collagen in compromised extraction sockets can improve bone formation and prevent dimensional shrinkage.

Periodontopathic bacteria are known to have a pivotal role in the pathogenesis of periodontitis. The aim of the study was to quantitatively compare bacterial profile of patients with different severity of periodontal disease using samples from mouthwash and the subgingival area. Further analysis was performed to evaluate the correlation between mouthwash and two subgingival sampling methods: paperpoint and gingival retraction cord, 114 subjects enrolled in the study, and were divided equally into three groups according to disease severity. Mouthwash and subgingival sampling were conducted, and the samples were quantitatively analyzed for 11 target periodontopathic bacteria using multiplex real-time PCR. There were statistically significant differences in bacterial counts and prevalence of several species between the study groups. Mouthwash sampling showed significant correlations with two different subgingival sampling methods in regard to the detection of several bacteria (e.g., &rho, = 0.793 for Porphyromonas gingivalis in severe periodontitis), implying that mouthwash sampling can reflect subgingival microbiota. However, the correlation was more prominent as disease severity increased. Although bacteria in mouthwash have potential to become a biomarker, it may be more suitable for the diagnosis of severe periodontitis, rather than early diagnosis. Further research is required for the discovery of biomarkers for early diagnosis of periodontitis.

This study aims to investigate and assess salivary biomarkers and microbial profiles as a means of diagnosing periodontitis. A total of 121 subjects were included: 28 periodontally healthy subjects, 24 with Stage I periodontitis, 24 with Stage II, 23 with Stage III, and 22 with Stage IV. Salivary proteins (including active matrix metalloproteinase-8 (MMP-8), pro-MMP-8, total MMP-8, C-reactive protein, secretory immunoglobulin A) and planktonic bacteria (including Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Fusobacterium nucleatum, Prevotella intermedia, Porphyromonas nigrescens, Parvimonas micra, Campylobacter rectus, Eubacterium nodatum, Eikenella corrodens, Streptococcus mutans, Staphylococcus aureus, Enterococcus faecalis, and Actinomyces viscosus) were measured from salivary samples. The performance of the diagnostic models was assessed by receiver operating characteristics (ROCs) and area under the ROC curve (AUC) analysis. The diagnostic models were constructed based on the subjects&rsquo, proteins and/or microbial profiles, resulting in two potential diagnosis models that achieved better diagnostic powers, with an AUC value &gt, 0.750 for the diagnosis of Stages II, III, and IV periodontitis (Model PA-I, AUC: 0.796, sensitivity: 0.754, specificity: 0.712) and for the diagnosis of Stages III and IV periodontitis (Model PA-II, AUC: 0.796, sensitivity: 0.756, specificity: 0.868). This study can contribute to screening for periodontitis based on salivary biomarkers.

Purpose The purpose of this study was to investigate the feasibility of regenerative therapy with a collagenated bone graft and resorbable membrane in intrabony defects, and to evaluate the effects of the novel extracellular matrix (ECM)-based membrane clinically and radiologically. Methods Periodontal tissue regeneration procedure was performed using an ECM-based resorbable membrane in combination with a collagenated bovine bone graft in intrabony defects around the teeth and implants. A novel extracellular matrix membrane (NEM) and a widely-used membrane (WEM) were randomly applied to the test group and the control group, respectively. Cone-beam computed tomography images were obtained on the day of surgery and 6 months after the procedure. Alginate impressions were taken and plaster models were made 1 week and 6 months postoperatively. Results The quantity of bone tissue, the dimensional changes of the surgically treated intrabony defects, and the changes in width and height below the grafted bone substitutes showed no significant difference between the test and control groups at the 6-month examination. Conclusions The use of NEM for periodontal regeneration with a collagenated bovine bone graft showed similar clinical and radiologic results to those obtained using WEM., Graphical Abstract

Purpose The aim of this study was to radiographically and clinically compare the effect of extracellular matrix (ECM) membranes on dimensional alterations following a ridge preservation procedure. Methods One of 2 different ECM membranes was applied during a ridge preservation procedure. A widely used ECM membrane (WEM; Bio-Gide, Geistlich Biomaterials, Wolhusen, Switzerland) was applied in the treatment group and a newly developed ECM membrane (NEM; Lyso-Gide, Oscotec Inc., Seongnam, Korea) was applied in the control group. Cone-beam computed tomography (CBCT) scans and alginate impressions were obtained 1 week and 6 months after the ridge preservation procedure. Results were analyzed using the independent t-test and the nonparametric Mann-Whitney U test. Results There were no significant differences between the ECM membranes in the changes in the dimension, width, and height of the extraction socket or the quantity of bone tissue. Conclusions The NEM showed comparable clinical and radiographic results to the WEM following the ridge preservation procedure., Graphical Abstract

Alveolar bone resorption caused by trauma or periodontal diseases has represented a challenge for both dental clinicians and researchers. In this study, we evaluate the osteogenic potential of human gingival fibroblasts (HGFs) through a direct transdifferentiation from HGFs to functional osteoblasts via epigenetic modification and osteogenic signaling with bone morphogenetic protein 2 (BMP2) in vitro and in vivo. HGF treatment with 5-aza-2′-deoxycytidine (5-aza-dC) induced demethylation in the hypermethylated CpG islands of the osteogenic lineage marker genes RUNX2 and ALP, and subsequent BMP2 treatment successfully drove the fibroblasts to the osteoblasts’ lineage. Cell morphological changes viewed under microscopy and alkaline phosphatase (ALP) and alizarin red S (ARS) staining confirmed the osteoblastic change mediated by epigenetic modification as did real-time polymerase chain reaction (PCR), methylation-specific PCR (MSP), and chromatin immunoprecipitation (ChIP) assay, which demonstrated the altered methylation patterns in the RUNX2 and ALP promoter regions and their effect on gene expression. Furthermore, micro–computed tomography (CT) analysis of in vivo mouse cell transplantation experiments showed high-density signal in the epigenetically modified HGF group; in addition, a significant amount of bone formation was observed in the transplanted material using hematoxylin and eosin (H&E) staining as well. Collectively, our results indicate that epigenetic modification permits the direct programming of HGFs into functional osteoblasts, suggesting that this approach might open a novel therapeutic avenue in alveolar bone regeneration.

There have been previous studies on the relationship between periodontitis and peri-implantitis, but limited information is available on how periodontitis affects osseointegration and wound healing of newly placed dental implants adjacent to natural teeth. The objective of the present experiment is to evaluate healing around dental implants adjacent to teeth with untreated experimental periodontitis.The study included six male beagle dogs. Scaling and plaque control procedures were performed on three dogs (control group). In the other three dogs (experimental group), retraction cords and ligature wires were placed subgingivally around all premolars and the first molars. Induced experimental periodontitis was confirmed after 3 months. Each control or experimental group was divided into two subgroups depending on the timing of implant placement (immediate/delayed). Twelve dental implants (two implants for each dog) were placed immediately, and the other 12 dental implants (two implants for each dog) were placed 2 months after extraction. The animals were sacrificed 2 months after implant placement. Histologic and histometric analyses were performed.Four implants (three from the immediate placement group and one from the delayed placement group) failed in the experimental group. There were significant differences in the percentage of bone-to-implant contact and marginal bone volume density between the control and experimental groups. Both parameters were significantly lower in the experimental group than in the control group (P0.05). There was a tendency toward more marginal bone loss in the experimental group than the control group.Immediate placement of implants is associated with a higher failure rate compared with delayed placement. Untreated experimental periodontitis was correlated with compromised osseointegration in the implants with delayed placement.

Background The aim of this study was to seek the critical time for impairment of alveolar bone regeneration after ovariectomy (OVX) in rats. Methods A total of 32 female rats were used. Test group rats were divided into a 2M group (n = 8), a 3M group (n = 8) and a 4M group (n = 8) according to the duration from OVX to defect creation. Bilateral OVX was performed in all test groups, and a sham operation was performed in the control group (n = 8). Drill-hole defects (1.5 mm diameter, 2 mm length) were created on both sides of the maxilla. All rats were euthanized 2 and 4 weeks after the surgery. Microcomputed tomographic (micro-CT), histological, and histomorphometric analyses and in vitro experiments were performed. Results The 4M group showed significantly less new bone formation and a lower bone mineral density than the other groups in the micro-CT analysis. The histomorphometric analysis also revealed that the 4M group showed significantly less new bone formation than the control and 2M groups. The rats in the 4M group showed significantly higher alkaline phosphatase expression levels and a larger number of calcified nodules than rats in the other groups, whereas osteoclastic activity was significantly lower in the 4M group than in the other groups. Conclusions The critical time for impairment of alveolar bone regeneration was 4 months after OVX in rats.

Ultraviolet (UV) photofunctionalization has been suggested as an effective method to enhance the osseointegration of titanium surface. In this study, machined surface treated with UV light (M + UV) was compared to sandblasted, large-grit, acid-etched (SLA) surface through in vitro and in vivo studies. Groups of titanium specimens were defined as machined (M), SLA, and M + UV for the disc type, and M + UV and SLA for the implant. The discs and implants were assessed using scanning electron microscopy, confocal laser scanning microscopy, electron spectroscopy for chemical analysis, and the contact angle. Additionally, we evaluated the cell attachment, proliferation assay, and real-time polymerase chain reaction for the MC3T3-E1 cells. In a rabbit tibia model, the implants were examined to evaluate the bone-to-implant contact ratio and the bone area. In the M + UV group, we observed the lower amount of carbon, a 0&deg, degree contact angle, and enhanced osteogenic cell activities (p &lt, 0.05). The histomorphometric analysis showed that a higher bone-to-implant contact ratio was found in the M + UV implant at 10 days (p &lt, 0.05). In conclusion, the UV photofunctionalization of a Ti dental implant with M surface attained earlier osseointegration than SLA.

Background Leukocyte- and platelet-rich fibrin (L-PRF) has been suggested to enhance bone healing and the effects of L-PRF need to be evaluated in lateral residual alveolar bone augmentation. This in vivo study aimed to analyze the effects of L-PRF as a membrane on bone regeneration in lateral residual alveolar augmentation. Methods Eight mongrel dogs were used; the mandibular premolars were extracted and then three lateral ridge defects were surgically created on each side of the arch. After 4 weeks, guided bone ridge augmentation was performed in each defect with the following treatment groups: N+D (nonresorbable membrane with deproteinized bovine bone mineral [DBBM]), N+B (nonresorbable membrane with β-tricalcium phosphate [β-TCP]), R+D (resorbable membrane with DBBM), R+B (resorbable membrane with β-TCP), and P+D (L-PRF with DBBM), and P+B (L-PRF and β-TCP). Following 4 weeks of bone healing, the new bone amount for each group was measured by light microscopy (primary outcome) and microcomputed tomography (micro-CT) (secondary outcome). The mean values were compared at the 0.05 significance level. Results The P+D group showed the most newly formed bone in histology and in micro-CT analyses. L-PRF was more effective in bone regeneration when compared to nonresorbable and resorbable barrier membranes. Additionally, this study indicated DBBM was the more favorable osseous graft material for bone regeneration than β-TCP when barrier membranes are used. Conclusion From the results of this in vivo study using surgically created defects, L-PRF plays an effective role as a barrier membrane for lateral ridge augmentation. L-PRF may be an excellent barrier membrane in place of other nonresorbable and resorbable membranes.

BACKGROUND The purpose of this study was to compare the survival rates of implants placed following 1-stage or 2-stage maxillary sinus floor augmentation by the lateral window technique (SFALW) performed on residual bone of

PURPOSE The design and surface features of dental implants substantially affect the healing and remodeling of adjacent bones. This study aimed to investigate the impact of design and surface on bone regeneration using implants of two different pitches, each with three different surface features. MATERIALS AND METHODS Custom-manufactured titanium implants (length, 10 mm; diameter, 3.5 mm) were divided along the major axis into two sections: one with 0.6-mm pitch and the other with 0.4-mm pitch. They were processed by turned, blasting and etching, and anodic oxidation surface treatments and implanted into rabbit tibia. The upper 4 mm of the inserted implants was exposed, and bone regeneration was induced around the exposed area using a titanium chamber (height: 4 mm) containing particulate autogenous and bovine bone. After a 12-week healing period, the quantity and quality of bone regeneration around the implants were evaluated. Thirty specimens-10 specimens each from the turned, blasting and etching, and anodic oxidation surface groups with 0.6- and 0.4-mm pitch sizes- were evaluated by histomophometric analysis. RESULTS The vertical height and width of regenerated bone around blasting and etching and anodic oxidation surfaces were significantly greater than those around turned implants (P < .05); the vertical heights of regenerated bone around the 0.4-mm-pitch sections of blasting and etching and anodic oxidation surfaces were significantly greater than those around the 0.6-mm-pitch sections (P < .05). Both blasting and etching and anodic oxidation surfaces exhibited significantly greater bone-to-implant contact and bone volume at the implant thread than turned implants (P < .05). However, there was no significant difference between the 0.6- and 0.4-mm-pitch sections. CONCLUSION The findings of this study indicate that blasting and etching and anodic oxidation surfaces with a 0.4-mm-pitch design result in greater vertical ingrowth of regenerated bone than those with a 0.6-mm-pitch design.

Background: Pain from local anesthetic injection makes patients anxious when visiting a dental clinic. This study aims to determine differences in pain according to types of local anesthetizing methods and to identify the possible contributing factors (e.g., dental anxiety, stress, and sex). Methods: Thirty-one patients who underwent open-flap debridement in maxillary premolar and molar areas during treatment for chronic periodontitis were evaluated for this study. A randomized, split-mouth, single-masked clinical trial was implemented. The dental anxiety scale (DAS) and perceived stress scale (PSS) were administered before surgery. Two lidocaine ampules for each patient were used for local infiltration anesthesia (supraperiosteal injection). Injection pain was measured immediately after local infiltration anesthesia using the visual analog pain scale (VAS) questionnaire. Results from the questionnaire were used to assess degree of pain patients feel when a conventional local anesthetic technique (CNV) is used compared with a computer-controlled anesthetic delivery system (CNR). Results: DAS and PSS did not correlate to injection pain. VAS scores were lower for CNR than for CNV regardless of the order in which anesthetic procedures were applied. VAS score did not differ significantly with sex. Pearson coefficient for correlation between VAS scores for the two procedures was 0.80, also indicating a strong correlation. Conclusion: Within the limitations of the present study, relief from injection pain is observed using CNR. J Periodontol 2016;87:783-789.

Purpose: The purpose of this prospective study was to assess the change of marginal bone level around three different types of external-hex implants after 5 years using radiography. Materials and Methods: Included in this study were 54 patients randomly put into three different groups; rough-surface implants (Branemark), machined coronal aspect implants (Restore), and microthreaded coronal aspect implants (Hexplant). Clinical and radiographic assessments were performed contemporaneously with implant loading (baseline) and at 1, 3, and 5 years post-functional loading. A mixed-model analysis was employed to examine mean marginal bone change significance in the three treatment groups. Results: In a total of 31 out of 54 patients, 81 of 135 implants remained to the end of the study. At 5 years, the microthreaded coronal aspect implants had 0.61 ± 0.32 mm mean crestal bone loss; the rough-surface implants without microthread, 0.99 ± 0.38 mm; and the machined coronal aspect implants, 1.06 ± 0.39 mm. The rough-surface implants and the machined coronal aspect implants did not exhibit statistically significantly different marginal bone loss, whereas the microthreaded coronal aspect implants exhibited significantly less marginal bone loss (P = .0015). Conclusion: In this research, rough-surface implants with microthreads showed positive long-term effects in preserving peri-implant bone level against functional loads when compared with implants lacking these aspects at the coronal part. Most of the bone loss was shown within 1 year of loading, and all types of implants stabilized after 1 year.

Purpose This article describes a case of the successful non-surgical management of a periodontally compromised maxillary premolar. Methods A combination therapy, including root planing, occlusal adjustment, and tooth splinting, was applied. Clinical and radiographic examinations were performed during the 16-month follow-up period. Results All periodontal parameters were improved. There were dramatic decreases (3–6 mm) in the probing pocket depth, tooth mobility, and marginal bone loss. Interestingly, gradual resolution of the periapical radiolucency and alveolar bone regeneration were observed in the radiographs, and the periodontal condition was maintained during the follow-up period. Conclusions Within the limits of this study, these results demonstrate the importance of natural tooth preservation through proper periodontal treatment and occlusal adjustment of the periodontally compromised tooth, which is typically targeted for tooth extraction and dental implantation., Graphical Abstract

Purpose The aim of this study was to investigate the efficacy and validity of subgingival bacterial sampling using a retraction cord, and to evaluate how well this sampling method reflected changes in periodontal conditions after periodontal therapy. Methods Based on clinical examinations, 87 subjects were divided into a healthy group (n=40) and a periodontitis group (n=47). Clinical measurements were obtained from all subjects including periodontal probing depth (PD), bleeding on probing (BOP), clinical attachment loss (CAL), and the plaque index. Saliva and gingival crevicular fluid (GCF) as a subgingival bacterial sample were sampled before and 3 months after periodontal therapy. The salivary and subgingival bacterial samples were analyzed by reverse-transcription polymerase chain reaction to quantify the following 11 periodontal pathogens: Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Tannerella forsythus (Tf), Treponema denticola (Td), Prevotella intermedia (Pi), Fusobacterium nucleatum (Fn), Pavimonas micra (Pm), Campylobacter rectus (Cr), Prevotella nigrescens (Pn), Eikenella corrodens (Ec), and Eubacterium nodatum (En). Results Non-surgical periodontal therapy resulted in significant decreases in PD (P, Graphical Abstract

Purpose Periodontitis and rheumatoid arthritis (RA) share a similar inflammatory pathogenesis. Porphyromonas gingivalis (Pg) can induce anticyclic-citrullinated peptide autoantibodies (anti-CCP antibodies), a key factor in the development of RA. This study aimed at evaluating the relationships between the 2 diseases and identifying the clinical implications thereof, with a focus on periodontal pathogens in Korean adults. Methods A total of 260 RA patients and 86 age- and sex-matched control patients without arthritis were enrolled in this prospective cross-sectional study. Periodontal indices and the prevalence and amount of periodontal pathogens were compared between the groups. Correlations between periodontal and RA indices were examined, as were correlations between 9 periodontal pathogens and RA indices. Results The RA group had significantly higher values than the control group for all investigated periodontal indices (P, Graphical Abstract

Purpose The aim of this study was to evaluate the capacity of single and combined applications of the bark of the stems and roots of Magnolia officinalis Rehd. et Wils. (Magnoliae Cortex) and Zea mays L. (maize) to modulate inflammation in RAW 264.7 cells stimulated with Porphyromonas gingivalis. Methods RAW 264.7 cells were stimulated with P. gingivalis, and Magnoliae Cortex and/or maize was added. Cytotoxicity and the capacity to modulate inflammation were determined with a methylthiazol tetrazolium (MTT) assay, nitrite production, enzyme-linked immunosorbent assay (ELISA), and western blotting. Results Treatment with Magnoliae Cortex and/or maize inhibited nuclear transcription factor κB (NF-κB) pathway activation and nuclear p44/42 mitogen-activated protein kinase (MAPK) and inducible nitric oxide synthase (iNOS) protein expression in P. gingivalis-stimulated RAW 264.7 cells. Moreover, the treatments suppressed cytokines (prostaglandin E2 [PGE2], interleukin [IL]-1β, and IL-6) and nitrite production. Conclusions Both Magnoliae Cortex and maize exerted an anti-inflammatory effect on P. gingivalis-stimulated RAW 264.7 cells, and this effect was more pronounced when the extracts were combined. These findings show that these extracts may be beneficial for slowing the progression of periodontal disease., Graphical Abstract

The application of bone morphogenetic protein 2 (BMP-2) has been extensively investigated to improve diabetes-impaired bone healing; however, the delivery of BMP-2 by gene therapy for bone regeneration has rarely been investigated in diabetic animals. In this study, we aimed to evaluate which cells induce more new bone formation in diabetic animals when cell-based BMP2 gene therapy is applied. For this purpose, we harvested bone marrow stromal cells (BMSCs) twice in the same animal before (non-diabetic BMSCs; nBMSCs) and after diabetes induction (diabetic BMSCs; dBMSCs) using modified bone marrow ablation methods. And then, cells were transduced by adenoviral vectors carrying the BMP2 gene (AdBMP2). In in vitro, AdBMP2-transfected dBMSCs (B2/dBMSCs) produced higher BMP-2 mRNA levels over 48 h, whereas AdBMP2-transfected nBMSCs (B2/nBMSCs) exhibited a transient increase in BMP-2 mRNA followed by a decrease to the baseline level within 48 h. Both B2/dBMSCs and B2/nBMSCs induced secretion of BMP-2 for 3 weeks. However, B2/dBMSC BMP-2 secretion peaked from day 3 to 10, whereas B2/nBMSC BMP-2 secretion peaked from day 1 to 7. The analysis of osteogenic activity revealed that mineralization nodule formation and the expression levels of osteogenic genes were significantly higher in B2/dBMSCs than B2/nBMSCs and were accompanied by upregulation of canonical Wnt/β-catenin and Smad signaling. AdBMP2-transfected autologous cells were implanted into critical-sized calvarial defects in diabetic animals and induced significantly more bone regeneration than non-AdBMP2-transfected cells. In addition, B2/dBMSCs led to significantly more new bone formation than B2/nBMSCs. Thus, BMP2 gene therapy using diabetic cells effectively supported diabetic bone healing and it was related to the enhanced responses to AdBMP2 of dBMSCs.

Material is a crucial factor for the restoration of the tooth or periodontal structure in dentistry. Various biomaterials have been developed and clinically applied for improved periodontal tissue regeneration and osseointegration, especially in periodontology and dental implantology. Furthermore, the biomimetic approach has been the subject of active research in recent years. In this review, the most widely studied biomaterials (bone graft material, barrier membrane, and growth or differentiation factors) and biomimetic approaches to obtain optimal tissue regeneration by making the environment almost similar to that of the extracellular matrix are discussed and specifically highlighted.

This study evaluates occurrence of progressive bone loss (PBL) around implants with different implant surfaces.Retrospective examination of 2,517 implants was performed in 903 patients, including 1,147 anodized-surface implants in 454 patients and 1,370 resorbable blasting media (RBM)-surface implants in 449 patients, which were placed from January 2006 to December 2010. Through regular check-up radiographs and records, presence of PBL (up to50% of fixture length) was investigated. Implant removal for any reason was regarded a failure.In total, 2,186 implants (979 anodized implants and 1,207 RBM implants) in 793 patients were included in this study. PBL was more frequently observed among anodized implants (n = 36 in 21 patients; 4%) than among RBM implants (n = 19 in 14 patients; 2%), and this difference was statistically significant (P0.001). Occurrence of PBL was significantly influenced by surface modification and implant diameter (odds ratio [OR] of anodized surface = 4.40, 95% confidence interval [CI] = 1.78 to 10.89, P = 0.001; OR of wide implants = 9.62, 95% CI = 1.13 to 81.68, P = 0.038; determined by mixed-effects logistic regression analysis with random patient effect). However, total survival rate was significantly influenced by implant diameter and not by surface modification (P = 0.019), although effect of implant diameter was observed to be significant on anodized implants (P = 0.030).Implant surface modification and implant diameter are significantly associated with occurrence of PBL.

Purpose This clinical pilot study was performed to determine the effectiveness of dual-energy cone-beam computed tomography (DE-CBCT) in measuring bone mineral density (BMD). Materials and Methods The BMD values obtained using DE-CBCT were compared to those obtained using calibrated multislice computed tomography (MSCT). After BMD calibration with specially designed phantoms, both DE-CBCT and MSCT scanning were performed in 15 adult dental patients. Three-dimensional (3D) Digital Imaging and Communications in Medicine data were imported into a dental software program, and the defined regions of interest (ROIs) on the 3-dimensional surface-rendered images were identified. The automatically-measured BMD values of the ROIs (g/cm3), the differences in the measured BMD values of the matched ROIs obtained by DE-CBCT and MSCT 3D images, and the correlation between the BMD values obtained by the 2 devices were statistically analyzed. Results The mean BMD values of the ROIs for the 15 patients as assessed using DE-CBCT and MSCT were 1.09±0.07 g/cm3 and 1.13±0.08 g/cm3, respectively. The mean of the differences between the BMD values of the matched ROIs as assessed using DE-CBCT and calibrated MSCT images was 0.04±0.02 g/cm3. The Pearson correlation coefficient between the BMD values of DE-CBCT and MSCT images was 0.982 (r=0.982, P

Purpose Direct application of atmospheric-pressure plasma jets (APPJs) has been established as an effective method of microbial decontamination. This study aimed to investigate the bactericidal effect of direct application of an APPJ using helium gas (He-APPJ) on Porphyromonas gingivalis biofilms on sandblasted and acid-etched (SLA) titanium discs. Methods On the SLA discs covered by P. gingivalis biofilms, an APPJ with helium (He) as a discharge gas was applied at 3 different time intervals (0, 3, and 5 minutes). To evaluate the effect of the plasma itself, the He gas–only group was used as the control group. The bactericidal effect of the He-APPJ was determined by the number of colony-forming units. Bacterial viability was observed by confocal laser scanning microscopy (CLSM), and bacterial morphology was examined by scanning electron microscopy (SEM). Results As the plasma treatment time increased, the amount of P. gingivalis decreased, and the difference was statistically significant. In the SEM images, compared to the control group, the bacterial biofilm structure on SLA discs treated by the He-APPJ for more than 3 minutes was destroyed. In addition, the CLSM images showed consistent results. Even in sites distant from the area of direct He-APPJ exposure, decontamination effects were observed in both SEM and CLSM images. Conclusions He-APPJ application was effective in removing P. gingivalis biofilm on SLA titanium discs in an in vitro experiment., Graphical Abstract

Purpose: Implant stability at the time of surgery is crucial for the long-term success of dental implants. Primary stability is considered of paramount importance to achieve osseointegration. The purpose of the present study was to investigate the correlation between the insertion torque and primary stability of dental implants using artificial bone blocks with different bone densities and compositions to mimic different circumstances that are encountered in routine daily clinical settings. Methods: In order to validate the objectives, various sized holes were made in bone blocks with different bone densities (#10, #20, #30, #40, and #50) using a surgical drill and insertion torque together with implant stability quotient (ISQ) values that were measured using the Osstell Mentor. The experimental groups under evaluation were subdivided into 5 subgroups according to the circumstances. Results: In group 1, the mean insertion torque and ISQ values increased as the density of the bone blocks increased. For group 2, the mean insertion torque values decreased as the final drill size expanded, but this was not the case for the ISQ values. The mean insertion torque values in group 3 increased with the thickness of the cortical bone, and the same was true for the ISQ values. For group 4, the mean insertion torque values increased as the cancellous bone density increased, but the correlation with the ISQ values was weak. Finally, in group 5, the mean insertion torque decreased as the final drill size increased, but the correlation with the ISQ value was weak. Conclusions: Within the limitations of the study, it was concluded that primary stability does not simply depend on the insertion torque, but also on the bone quality.