Improvement of periodontal parameters following intensive diabetes care and supragingival dental prophylaxis in patients with type 2 diabetes: A prospective cohort study.

AIM: This study aimed to investigate the effects of diabetes care on periodontal inflammation. MATERIALS AND METHODS: This prospective cohort study included 51 Japanese patients with type 2 diabetes who underwent intensive diabetes care including educational hospitalization and regular outpatient treatment for 6 months. Dental prophylaxis without subgingival scaling was provided three times during the observational period. Associations between changes in periodontal parameters and glycaemic control levels were evaluated using multiple regression analysis. RESULTS: Overall, 33 participants (mean age: 58.7 ± 12.9) were followed up for 6 months. At baseline examination, 82% were diagnosed with Stage III or IV periodontitis. Haemoglobin A1c (HbA1c) level changed from 9.6 ± 1.8% at baseline to 7.4 ± 1.3% at 6 months. The ratio of probing pocket depth (PPD) ≥4 mm, bleeding on probing (BOP), full-mouth plaque control record (PCR), periodontal epithelial surface area (PESA) and periodontal inflamed surface area (PISA) also significantly improved. The reduction in PPD and PESA was significantly associated with changes in both HbA1c and fasting plasma glucose (FPG) levels, and the reduction in PISA was significantly associated with an improvement in FPG after adjusting for smoking, change in body mass index and full-mouth PCR. CONCLUSIONS: This is the first study to report a significant improvement in PPD and BOP after intensive diabetes care and dental prophylaxis without subgingival scaling. CLINICAL TRIAL REGISTRATION NUMBER: UMIN000040218.

Current status of Er:YAG laser in periodontal surgery.

Lasers have numerous advantageous tissue interactions such as ablation or vaporization, hemostasis, bacterial killing, as well as biological effects, which induce various beneficial therapeutic effects and biological responses in the tissues. Thus, lasers are considered an effective and suitable device for treating a variety of inflammatory and infectious conditions of periodontal disease. Among various laser systems, the Er:YAG laser, which can be effectively and safely used in both soft and hard tissues with minimal thermal side effects, has been attracting much attention in periodontal therapy. This laser can effectively and precisely debride the diseased root surface including calculus removal, ablate diseased connective tissues within the bone defects, and stimulate the irradiated surrounding periodontal tissues during surgery, resulting in favorable wound healing as well as regeneration of periodontal tissues. The safe and effective performance of Er:YAG laser-assisted periodontal surgery has been reported with comparable and occasionally superior clinical outcomes compared to conventional surgery. This article explains the characteristics of the Er:YAG laser and introduces its applications in periodontal surgery including conventional flap surgery, regenerative surgery, and flapless surgery, based on scientific evidence from currently available basic and clinical studies as well as cases reports.

Enhanced periodontal tissue healing via vascular endothelial growth factor expression following low-level erbium-doped: yttrium, aluminum, and garnet laser irradiation: In vitro and in vivo studies.

BACKGROUND: This study aimed to investigate the effects of low-level erbium-doped: yttrium, aluminum, and garnet (Er:YAG) laser irradiation on periodontal tissue healing and regeneration through angiogenesis in vivo and in vitro studies. METHODS: Intrabony defects were surgically created in the bilateral maxilla molar of rats. The defects were treated by open flap debridement (OFD) with Er:YAG laser, including low-level laser irradiation (LLLI) to bone and blood clot surfaces, or conventional procedures. The mRNA expression of vascular endothelial growth factor (VEGF) in the surgical sites was quantified using real-time polymerase chain reaction. The decalcified specimens were prepared for histometric analysis. Also, LLLI was performed on human umbilical vein endothelial cells to evaluate the effects on angiogenesis. Cell proliferation, VEGF expression, and tube formation were assessed. In addition, capsazepine (CPZ), a selective inhibitor of transient receptor potential vanilloid 1 (TRPV1), treatment was performed before LLLI for the same assays. RESULTS: OFD using Er:YAG laser did not generate thermal damage on bone or root surfaces. LLLI accelerated hemostasis by coagulation of the superficial layers of blood clots in the laser-treated group. Postoperative healing was sound in all animals in both groups. VEGF expression and bone formation were significantly increased in the laser-treated group compared to those in the conventional treatment group. In vitro, cell proliferation and VEGF expression were significantly increased in the LLLI group compared to the control group. Tube-formation assays showed that LLLI significantly promoted angiogenesis. CPZ treatment significantly suppressed VEGF expression and tube formation following LLLI. CONCLUSIONS: This study suggests that Er:YAG laser irradiation may promote periodontal tissue healing by enhancing angiogenetic effect of endothelial cells via TRPV1.

The Potential of a Saliva Test for Screening of Alveolar Bone Resorption.

Oral health screening is important for maintaining and improving quality of life. The present study aimed to determine whether patients with a certain level of alveolar bone resorption could be screened by salivary bacterial test along with their background information. Saliva samples were collected from 977 Japanese patients, and the counts of each red-complex, that is, Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia, were measured using quantitative polymerase chain reaction analysis. Mean bone crest levels (BCLs) were measured using a full-mouth periapical radiograph. Multiple logistic regression analysis was used to determine associations between BCLs (1.5-4.0 mm in 0.5 mm increments) and explanatory variables, such as the number of each red-complex bacteria and the patients' age, sex, number of teeth, stimulated saliva volume, and smoking habits. When the cutoff BCL value was set at 3.0 mm, the area under the curve, sensitivity, and specificity values were optimal at 0.86, 0.82, and 0.76, respectively. In addition, all tested explanatory variables, except sex and T. denticola count, were significantly associated with BCLs according to a likelihood ratio test (p < 0.05). Additionally, the odds ratio (OR) was substantially increased when a patient was >40 years old and the bacterial count of P. gingivalis was >107 cells/µL (OR: >6). Thus, P. gingivalis count and patients' background information were significantly associated with the presence of a certain amount of bone resorption, suggesting that it may be possible to screen bone resorption without the need for radiography or oral examination.

Er:YAG laser-assisted comprehensive periodontal pocket therapy for residual periodontal pocket treatment: A randomized controlled clinical trial.

BACKGROUND: This study evaluated the effectiveness of a novel pocket therapy (Er:YAG laser-assisted comprehensive periodontal pocket therapy [Er-LCPT]) for residual pocket treatment, compared with conventional mechanical treatment alone, in a randomized controlled clinical trial. METHODS: Two sites in 18 patients having residual periodontal pockets of ≥5 mm depth, extant following initial active therapy, or during supportive therapy, were randomized into two groups in a split mouth design: the control group received scaling and root planing (SRP) by curette, and the test group received Er-LCPT using curette and laser. With Er-LCPT, after root debridement, inflamed connective tissue on the inner gingival surface and on the bone surface/within extant bone defects was thoroughly debrided. Furthermore, removal of proximate oral epithelium and coagulation of the blood clot in the pocket entrance were performed with laser. Clinical parameters were evaluated, before and after treatment, through 12 months. RESULTS: Both groups showed significant improvements in clinical parameters. With Er-LCPT, pocket debridement was thoroughly and safely performed, without any adverse side effects and complications, and favorable healing was observed in most of the cases. At 12 months, Er-LCPT demonstrated significantly higher probing pocket depth reduction (2.78 mm vs. 1.89 mm on average; p = 0.012, Wilcoxon signed-rank test), clinical attachment gain (1.67 mm vs. 1.06 mm; p = 0.004) as primary outcomes, and reduced BOP value (0.89 vs. 0.56; p = 0.031), compared with SRP alone. CONCLUSION: The results of this study indicate that Er-LCPT is more effective for residual pocket treatment, compared with SRP alone.

Income-related inequalities in the association of smoking with periodontitis: a cross-sectional analysis in Tokyo Metropolitan Districts.

OBJECTIVE: Socio-economic status (SES) and smoking are risk factors for periodontitis; however, their interaction has not been determined. We investigated the effect of modification of SES and smoking with periodontal conditions. MATERIALS AND METHODS: Data on the social background, smoking status, and dental examination of 1033 individuals residing in the Tokyo Metropolitan District were analyzed. The outcomes were the number of remaining teeth and the proportion of teeth with probing pocket depth (PPD) ≥ 4 mm and ≥ 6 mm. Multilevel linear and Poisson regression analyses were performed after adjusting for possible confounding factors, including SES, assessed by the average income of the residential area. RESULTS: The mean number of remaining teeth was 24.6 ± 4.8, and the proportion of teeth with PPD ≥ 4 mm and ≥ 6 mm was 31.2 ± 28.5% and 12.2 ± 18.1%, respectively. After adjusting for confounding factors, the lowest-income population had significantly lesser teeth (coefficient: - 0.46, 95% CI - 0.89, 0.02, p = 0.039) and a higher proportion of teeth with PPD ≥ 4 mm than the highest-income population (ratio of means: 1.22, 95% CI 1.03-1.44, p = 0.013). Significant interactions were observed; income inequalities in periodontitis were significant only among current smokers. CONCLUSION: Inequality in socio-economic status is associated with oral health inequalities. The adverse effects of smoking on periodontitis might be greater in the low-income population. CLINICAL RELEVANCE: The low-income population, especially current smokers, had significantly more compromised oral health than the high-income population. In addition to the emphasis on smoking cessation, the promotion of universal health coverage for dental care is necessary to reduce oral health inequalities.

Prognostic factors affecting periodontal regenerative therapy using recombinant human fibroblast growth factor-2: A 3-year cohort study.

Introduction: Fibroblast growth factor-2 (FGF-2) has been reported to promote periodontal tissue regeneration. However, no study has investigated the long-term prognosis of periodontal regenerative therapy using FGF-2 to date. The aim of this study was to observe the long-term outcomes as well as to investigate the factors affecting the prognosis of periodontal regenerative therapy using FGF-2. Methods: Sixty intrabony defects were prospectively investigated for three years after periodontal regenerative therapy with recombinant human FGF-2 (rhFGF-2) by evaluating probing pocket depth (PPD) and radiographic bone defect depth (RBD). The factors influencing RBD were assessed by conducting a multivariate linear regression analysis after adjusting for confounders. Results: The mean age of the participants was 62.4 ± 13.4 years, and baseline PPD and RBD were 6.1 ± 1.9 mm and 4.5 ± 1.8 mm, respectively. At six months, one year, and three years after surgery, PPD and RBD had significantly improved to 4.2 ± 1.7, 3.7 ± 1.4, 4.0 ± 1.9 mm and to 3.08 ± 2.05, 2.73 ± 1.90, 2.51 ± 2.15 mm, respectively. At the three-year examination, a significant positive association was deteced between RBD reduction and RBD at baseline, while the association was not significant between RBD reduction and the radiographic bony angle, number of bony walls of the defect, or the furcation involvement at baseline. Conclusions: rhFGF-2 was effective for alveolar bone regeneration in patients with periodontitis and maintained the improved parameters over the three-year observation period. The radiographic bone defect depth at baseline was found to be the factor affecting the periodontal regenerative therapy using rhFGF-2 in the intrabony defects. Trial registration number: UMIN000027979.

Impaired dental implant osseointegration in rat with streptozotocin-induced diabetes.

OBJECTIVE: Few studies have reported on the impact of oxidative stress on the dental implant failure. The aim of this study was to investigate the impact of hyperglycemia-induced oxidative stress on dental implant osseointegration in diabetes mellitus (DM). METHODS: Acid-treated titanium implants were bilaterally placed in the maxillary alveolar ridge of streptozotocin-induced diabetic (DM group) and control rats after extraction of first molars. Histological analysis and micro-push-out test were performed 4 weeks after surgery. Oxidative stress and osteogenic markers in the surrounding bone were quantified by real-time polymerase chain reaction. In the in vitro study, rat bone marrow-derived mesenchymal stem cells (BMMSCs) were cultured on acid-treated titanium discs in a high-glucose (HG) or normal environment. Intracellular reactive oxygen species (ROS), cell proliferation, alkaline phosphatase (ALP) activity, and extracellular calcification were evaluated following antioxidant treatment with N-acetyl-L-cysteine (NAC). RESULTS: The implant survival rate was 92.9% and 75.0% in control and DM group, respectively. Bone-implant contact and push-out loads were significantly lower in the DM group. Expression of superoxide dismutase 1 at the mRNA level and on immunohistochemistry was significantly lower in the DM group. In vitro experiments revealed that the HG condition significantly increased ROS expression and suppressed the proliferation and extracellular calcification of BMMSCs, while NAC treatment significantly restored ROS expression, cell proliferation, and calcification. The ALP activity of both groups was not significantly different. CONCLUSION: In diabetes, high-glucose-induced oxidative stress downregulates proliferation and calcification of BMMSCs, impairing osseointegration and leading to implant failure.

Novel flapless esthetic procedure for the elimination of extended gingival metal tattoos adjacent to prosthetic teeth: Er:YAG laser micro-keyhole surgery.

PURPOSE: This article describes a novel, minimally invasive procedure called Er:YAG laser micro-keyhole surgery (EL-MIKS) that removes metal or amalgam tattoos in the gingiva adjacent to prosthetic teeth without gingival deformity and recession. We aimed to evaluate the clinical efficacy of EL-MIKS for removing metal tattoos and present its long-term treatment outcomes. METHODS: The EL-MIKS procedure consists of several steps that are all performed under a microscope. First, a micro-keyhole (1-2 mm diameter) was prepared using an Er:YAG laser in the center of the metal pigmentation. The connective tissue was evaporated in the deep layer, where metal debris was deposited. Second, within the accessible range, the irradiation angle was changed in various directions to ablate the metal pieces and discolored connective tissue without enlarging the keyhole. Finally, after blood filled the space created by the tissue evaporation, the surface of the blood clot at the entrance of the micro-keyhole was thermally coagulated with defocus laser irradiation. Pigmentation that could not be successfully removed from a single micro-keyhole was treated by forming new micro-keyholes at a distance of 3 mm or more from each previously created hole. Depigmentation over an extended area was completed over a few sessions every 4 weeks without gingival recession after surgery. CONCLUSION: EL-MIKS, a novel depigmentation technique, was able to successfully remove an extended area of metal tattoos in the gingiva using a simpler, easier, and less invasive procedure than conventional periodontal plastic surgery. Esthetic restoration was successfully achieved without postoperative alteration of the gingival contour.

Metformin accelerates wound healing by Akt phosphorylation of gingival fibroblasts in insulin-resistant prediabetes mice.

BACKGROUND: This study aimed to investigate the effects of metformin on gingival wound healing in insulin-resistant prediabetes. METHODS: C57BL/6J mice were fed normal diet (ND) or high-fat diet (HFD) for 10 weeks; half of the HFD mice were treated with metformin (HFD+ Met) for the last 2 weeks. Insulin and glucose tolerance tests were performed. The palatal gingiva (2.0 × 0.5 mm) was surgically removed adjacent to the maxillary molars. Post-surgical wound closure was histomorphometrically evaluated for 1 week. The mRNA expression of vascular endothelial growth factor (VEGF) and endothelial nitric oxide synthase (eNOS) in the tissue were quantified by real-time polymerase chain reaction. In vitro, the proliferation and migration of human gingival fibroblasts (HGFs) cultured under high-glucose or control conditions with/without metformin were analyzed. Akt phosphorylation and VEGF expression following the insulin stimulation were evaluated with/without metformin in high-glucose or control media. RESULTS: HFD mice showed significantly higher plasma glucose levels and insulin resistance than ND mice. Gingival wound healing was delayed in HFD group compared with ND group but significantly improved in HFD + MET group. The decreased expression of VEGF and eNOS in HFD group was significantly elevated in the HFD + MET group. The proliferation and migration of HGFs were significantly impaired in high-glucose conditions compared with control; metformin treatment partially attenuated these effects. Metformin treatment significantly recovered the downregulated Akt phosphorylation and VEGF expression in high-glucose conditions. CONCLUSIONS: Metformin improved delayed gingival wound healing in insulin-resistant prediabetes by accelerating HGFs proliferation and migration via Akt phosphorylation in insulin signaling pathway.

Residual periodontal pocket treatment with Er:YAG laser-assisted comprehensive periodontal pocket therapy: a retrospective study.

OBJECTIVES: Recently, the application of erbium-doped yttrium aluminum garnet (Er:YAG) laser has been increasing in periodontal therapy. In this retrospective study, we evaluated the safety and effectiveness of a novel pocket therapy using Er:YAG laser in combination with conventional mechanical scaling and root planing treatment (Er:YAG laser-assisted comprehensive periodontal pocket therapy). METHODS: Forty sites in 29 elderly patients having residual periodontal pockets of ≥ 5 mm depth were treated by curette and Er:YAG laser from 2006 to 2009. After root debridement by curette, laser irradiation was performed on the root surfaces. Then, inflamed connective tissue on the inner gingival surface and on the bone surface/within extant bone defects was thoroughly debrided by curette and laser. Furthermore, in most cases, removal of the outer epithelium and coagulation of the blood clot in the pocket entrance were additionally performed with laser. Clinical parameters were evaluated before and 3, 6, and 12 months after treatment. RESULTS: With Er:YAG laser-assisted pocket therapy, debridement of pockets was thoroughly and safely performed, and favorable clinical improvements were observed in most cases, without any adverse side effects and complications. After 1 year, probing pocket depth significantly decreased from 6.4 ± 1.4 to 3.5 ± 1.3 mm (p < 0.001, 3.0 mm reduction), and clinical attachment level significantly decreased from 7.5 ± 1.6 to 5.2 ± 1.9 mm (p < 0.001, 2.3 mm gain). CONCLUSION: The results of this study indicate that Er:YAG laser-assisted therapy is useful for the treatment of residual pockets as a minimally invasive flapless surgery. CLINICAL RELEVANCE: Er:YAG laser-assisted comprehensive pocket therapy reduces the necessity of more conventional surgical therapies.

Association between periodontal inflammation and serum lipid profile in a healthy population: A cross-sectional study.

AIMS: The impact of periodontal inflammation on lipid metabolism is controversial. This study aimed to investigate the association between full-mouth periodontal inflammation and serum lipid levels. MATERIALS AND METHODS: In this cross-sectional study, we performed periodontal and bacteriological examinations during medical checkup on 131 subjects. The association between the periodontal inflamed surface area (PISA) and the lipid markers was analyzed by multiple linear regression, adjusting for age, sex, smoking, and body mass index. RESULTS: Overall, 118 medically healthy participants were analyzed. The proportions of none, mild, moderate, and severe periodontitis were 37.3%, 32.2%, 25.4%, and 5.1%, respectively. Multivariate analysis showed that high-density lipoprotein cholesterol was significantly higher in participants with the lowest tertile of PISA values (PISA low, coefficient: 7.94; 95% confidence interval [CI]: 1.63, 14.26, p = .01) compared to those in other tertiles (PISA high). Low-density/high-density lipoprotein cholesterol and total/high-density lipoprotein cholesterol ratios were significantly lower in the PISA-low group than the PISA-high group (coefficient: -0.26 and -0.30; 95% CI: -0.50, -0.02, and -0.59, -0.0002; p = .04 and .0498). Serum high-sensitivity C-reactive protein level, but not serum Porphyromonas gingivalis antibody titer, partly explained the association between PISA and high-density lipoprotein cholesterol. A significant interaction between female sex and PISA values toward high-density lipoprotein cholesterol level was detected. CONCLUSION: Periodontal inflammation was inversely associated with higher high-density lipoprotein cholesterol, especially in females. Elevated serum C-reactive protein partly explained this association.

Association of periodontal pocket area with type 2 diabetes and obesity: a cross-sectional study.

INTRODUCTION: The aim was to investigate the relationship of full-mouth inflammatory parameters of periodontal disease with diabetes and obesity. RESEARCH DESIGN AND METHODS: This cross-sectional study conducted diabetes-related examinations and calculated periodontal inflamed and epithelial surface area (PISA and PESA) of 71 Japanese patients with type 2 diabetes. Multiple linear regression analyses were performed to evaluate associations between PISA or PESA and diabetes and obesity parameters. RESULTS: Median value of body mass index (BMI), hemoglobin A1c (HbA1c) level, fasting plasma glucose (FPG) level, and visceral fat area (VFA) were 25.7 kg/m2, 9.1%, 151 mg/L, and 93.3 cm2, respectively. PISA and PESA were significantly associated with HbA1c after adjusting for age, sex, BMI, smoking status, and full-mouth plaque control level (PISA: coefficient=38.1, 95% CI 8.85 to 67.29, p=0.001; PESA: coefficient=66.89, 95% CI 21.44 to 112.34, p=0.005). PISA was also significantly associated with the highest FPG tertile (>175 mg/dL) after adjusting for confounders (coefficient=167.0, 95% CI 48.60 to 285.4, p=0.006). PISA and PESA were not significantly associated with BMI or VFA. CONCLUSION: PISA was associated with FPG and HbA1c, but not with obesity parameters, independent from confounders such as full-mouth plaque control level in patients with type 2 diabetes.

A novel minimally-invasive approach for metal tattoo removal with Er:YAG laser.

OBJECTIVE: Few effective and established treatment methods can remove gingival metal or amalgam tattoos. With this case series, we aimed to demonstrate the use of a novel minimally invasive technique to remove metal tattoos using an erbium-doped yttrium aluminum garnet (Er:YAG) laser. MATERIALS AND METHODS: We retrospectively collected clinical data from 18 patients who had undergone Er:YAG laser treatment to remove metal tattoos. Minimal gingival ablation using an Er:YAG laser directed towards the pigmented area was performed, which exposed metal debris within the connective tissue that was carefully removed. A dental microscope was employed to identify the metal debris, for accurate irradiation, and to minimize wounding by reducing invasion. Postoperative gingival color and morphology, and visual analog scale as a patient-reported outcome assessing postoperative pain were evaluated. RESULTS: All patients' metal tattoos were removed completely and safely during short procedures. Considerable esthetic improvements and favorable wound healing were achieved with almost no postoperative pain or complications. CONCLUSION: The findings from this case series suggest that this novel minimally invasive therapy for metal tattoo removal that involved the Er:YAG laser is effective and safe, is associated with successful outcomes, and contributes greatly to patients' esthetic satisfaction. CLINICAL SIGNIFICANCE: Metal tattoo removal using an Er:YAG laser safely and successfully improved gingival esthetics. This novel technique is much simpler and less invasive than conventional periodontal plastic surgery, and it may be more reliable regarding esthetic gingival improvements as it is associated with favorable wound healing, and it could offer significant benefits to patients by alleviating physical and mental stresses via reduced chair time and postoperative pain.

Association between circulating tumor necrosis factor receptors and oral bacterium in patients receiving hemodialysis: a cross-sectional study.

BACKGROUND: High levels of tumor necrosis factor (TNF) receptors (TNFRs; TNFR1 and TNFR2), markers of inflammation, have been reported as significant predictors of mortality in hemodialysis patients. Porphyromonas gingivalis is a major pathogenic bacterium involved in periodontitis, which induces systemic inflammation. We investigated the association between the abundance of P. gingivalis in saliva and serum TNFR levels in hemodialysis patients. METHODS: A cross-sectional study was conducted on 121 hemodialysis patients visiting a clinic in the Tokyo metropolitan area. Medical interviews and examinations, comprehensive dental examinations, bacterial examinations for P. gingivalis in saliva, and measurements of circulating TNFR levels were conducted. Multiple linear regression analysis was performed to evaluate the association between the number of P. gingivalis and circulating TNFR levels. RESULTS: TNFR1 and TNFR2 were positively correlated with high-sensitivity C-reactive protein (hsCRP). Severe periodontitis was significantly associated with the number of P. gingivalis in saliva but not serum TNFR levels. The number of P. gingivalis was significantly associated with both TNFR1 and TNFR2 levels in sera after adjusting for age, sex, body mass index, smoking status, history of diabetes, prior cardiovascular disease events, serum levels of hsCRP and albumin, and severity of periodontitis [for TNFR1: coefficient 0.76, 95% confidence interval (CI) 0.14-1.37, p = 0.02; for TNFR2: coefficient 0.95, 95% CI 0.09-1.80, p = 0.03]. CONCLUSION: Circulating TNFR levels are associated with the number of P. gingivalis in saliva after adjusting for relevant clinical factors.

Periodontal regenerative therapy in patients with type 2 diabetes using minimally invasive surgical technique with enamel matrix derivative under 3-year observation: A prospective cohort study.

BACKGROUND: Information regarding periodontal regenerative therapy in patients with diabetes mellitus (DM) is limited. This pilot study compared the regenerative outcomes of minimally invasive periodontal surgery using enamel matrix derivative (EMD) between DM and non-DM patients. METHODS: This prospective study included deep intrabony defects in patients with or without type 2 DM. Minimally invasive surgical technique (MIST) or modified MIST (M-MIST) using EMD, without bone graft materials, was performed. Periodontal examination and intraoral radiography were performed at baseline, 6 months, and 1 and 3 years after surgery. RESULTS: Ten sites of 10 subjects in the DM group, and 20 sites of 18 subjects in non-DM group were evaluated (mean age; 67.5 ± 7.6 and 63.1 ± 9.7, respectively). Probing depth significantly decreased from 7.1 ± 1.6 and 7.0 ± 1.3 mm to 2.2 ± 0.9 and 2.3 ± 1.1 mm at the 1-year examination in the DM and non-DM groups, respectively. Clinical attachment level (CAL) gain and radiographical defect fill at the 3-year examination were 3.8 ± 1.1 mm and 58.3% ± 10.4%, respectively, in the DM group, and 4.1 ± 1.1 mm and 65.5% ± 18.8%, respectively, in the non-DM group, showing no significant differences between the groups. Multiple regression analysis showed no significant association of CAL gain with DM or age after adjustments for relevant confounders. CONCLUSIONS: This is the first documented study of successful periodontal tissue regeneration in patients with DM. Minimally invasive surgery combined with EMD yielded significant clinical attachment gain and bone fill in the DM and non-DM groups at comparable levels.

Poor oral hygiene and dental caries predict high mortality rate in hemodialysis: a 3-year cohort study.

The aim of this study was to investigate the impact of oral hygiene, periodontal diseases, and dental caries on all-cause mortality in hemodialysis. This prospective cohort study included 266 patients with end-stage renal disease who were undergoing hemodialysis. Medical interviews, blood biochemical tests, and comprehensive dental examinations including periodontal pocket examination on all teeth and dental plaque accumulation by debris index-simplified (DI-S), were performed. Survival rates were assessed at a 3-year follow-up. Overall, 207 patients were included in the longitudinal analysis, and 38 subjects died during the follow-up period. Cox proportional hazards analysis of the multivariate model demonstrated that the highest tertile of DI-S had a significantly higher risk of all-cause mortality than the lowest two tertiles after adjustment for age, sex, smoking habit, body mass index, diabetes, prior cardiovascular disease, hemodialysis vintage, high sensitivity C-reactive protein, albumin, and number of remaining teeth (hazard ratio, 3.04; 95% confidence interval, 1.50-6.17; p = 0.002). Moreover, the number of decayed teeth significantly increased the hazard ratio to 1.21 (95% confidence interval, 1.06.1.37; p = 0.003). This study suggests that accumulated dental plaque and untreated decay, but not periodontal disease, may be independently associated with all-cause mortality in patients undergoing hemodialysis.

Patient-reported outcomes of laser-assisted pain control following non-surgical and surgical periodontal therapy: A systematic review and meta-analysis.

Adjunctive use of laser devices as high reactive-level laser/light therapy (HLLT) or photobiomodulation therapy (PBMT) for periodontal therapy is known to be more effective on suppressing pain than conventional therapy, however, there are no systematic reviews addressed its effectiveness. This systematic review and meta-analysis aim to investigate the following clinical question (CQ): does adjunctive use of lasers with conventional therapy suppress the pain associated with periodontal treatment? A systematic and extensive literature search was performed to summarize the currently available knowledge to answer the CQ using the PubMed, Cochrane Library, and Web of Science databases for randomized controlled trials (RCTs) conducted before June 2020. Bias risk was assessed using the Cochrane tool for the risk of bias evaluation. A meta-analysis was performed on quantitative evaluation of pain control based on patient-reported outcomes. After an independent screening of 165 initial records, ten RCTs were included. Six of them focused on surgical procedures and the others on non-surgical periodontal pocket therapy. The protocols of HLLT, PBMT, and combination with HLLT and PBMT were employed in five, four and one RCTs, respectively. Following the assessment of bias risk, it is revealed that all RCTs had methodological weaknesses regarding the blinding of key personnel, although other bias risk factors were not evident. Meta-analysis showed that HLLT using erbium lasers significantly reduced the patient-reported pain immediately after treatment (two RCTs, p < 0.0001), while PBMT using diode lasers significantly reduced pain 2-7 days after treatment (two RCTs, p < 0.0001 to p = 0.03). The presented systematic review and meta-analysis suggest that the alternative use of HLLT using erbium lasers to conventional instrumentation can significantly suppress postoperative pain and that intraoperative or postoperative PBMT using diode lasers combined with periodontal surgery can significantly reduce postoperative pain. However, the evidence is still insufficient and more well-designed RCTs are required.

Periodontal regenerative effect of enamel matrix derivative in diabetes.

The present study aimed to investigate the periodontal regenerative effect of enamel matrix derivative (EMD) in diabetes. Thirty-six rats were assigned to streptozotocin-induced diabetes or control (non-diabetic) groups. Three-wall intrabony defects were surgically generated in the bilateral maxilla molar, followed by application of EMD or saline. Primary wound closure and defect fill were evaluated via histomorphological analysis and micro-computed tomography. mRNA expression levels of inflammatory and angiogenic factors in the defects were quantified via real-time polymerase chain reaction. Gingival fibroblasts were isolated from control animals and cultured in high-glucose (HG) or control medium. The effects of EMD on insulin resistance and PI3K/Akt/VEGF signaling were evaluated. The achievement rate of primary closure and the parameters of defect fill were significantly higher at EMD-treated site than at EMD-untreated sites in both diabetic and non-diabetic rats, although defect fill in the diabetic groups was significantly lower in the control groups on two-way repeated-measures analysis of variance (for both, p<0.05). Newly formed bone and cementum were significantly increased at EMD-treated sites in diabetic rats than at EMD-untreated sites in control rats (for both, p<0.05). Vegf was significantly upregulated at EMD-treated sites in both diabetic and non-diabetic rats (for both, p<0.05). In vitro, insulin or EMD-induced Akt phosphorylation was significantly lower in cells cultured in HG medium (p<0.05). EMD-mediated Vegf upregulation was suppressed by the Akt inhibitor wortmannin, although the effect was significantly lower in HG medium (p<0.01). In conclusion, EMD might promote periodontal tissue regeneration via Akt/VEGF signaling, even in a diabetic condition.

Low-level ultrahigh-frequency and ultrashort-pulse blue laser irradiation enhances osteoblast extracellular calcification by upregulating proliferation and differentiation via transient receptor potential vanilloid 1.

BACKGROUND AND OBJECTIVE: Low-level laser irradiation (LLLI) exerts various biostimulative effects, including promotion of wound healing and bone formation; however, few studies have examined biostimulation using blue lasers. The purpose of this study was to investigate the effects of low-level ultrahigh-frequency (UHF) and ultrashort-pulse (USP) blue laser irradiation on osteoblasts. STUDY DESIGN/ MATERIALS AND METHODS: The MC3T3-E1 osteoblast cell line was used in this study. Following LLLI with a 405 nm newly developed UHF-USP blue laser (80 MHz, 100 fs), osteoblast proliferation, and alkaline phosphatase (ALP) activity were assessed. In addition, mRNA levels of the osteoblast differentiation markers, runt-related transcription factor 2 (Runx2), osterix (Osx), alkaline phosphatase (Alp), and osteopontin (Opn) was evaluated, and extracellular calcification was quantified. To clarify the involvement of transient receptor potential (TRP) channels in LLLI-induced biostimulation, cells were treated prior to LLLI with capsazepine (CPZ), a selective inhibitor of TRP vanilloid 1 (TRPV1), and subsequent proliferation and ALP activity were measured. RESULTS: LLLI with the 405 nm UHF-USP blue laser significantly enhanced cell proliferation and ALP activity, compared with the non-irradiated control and LLLI using continuous-wave mode, without significant temperature elevation. LLLI promoted osteoblast proliferation in a dose-dependent manner up to 9.4 J/cm2 and significantly accelerated cell proliferation in in vitro wound healing assay. ALP activity was significantly enhanced at doses up to 5.6 J/cm2 , and expression of Osx and Alp mRNAs was significantly increased compared to that of the control on days 3 and 7 following LLLI at 5.6 J/cm2 . The extent of extracellular calcification was also significantly higher as a result of LLLI 3 weeks after the treatment. Measurement of TRPV1 protein expression on 0, 3, and 7 days post-irradiation revealed no differences between the LLLI and control groups; however, promotion of cell proliferation and ALP activity by LLLI was significantly inhibited by CPZ. CONCLUSION: LLLI with a 405 nm UHF-USP blue laser enhances extracellular calcification of osteoblasts by upregulating proliferation and differentiation via TRPV1. Lasers Surg. Med. 50:340-352, 2018. © 2017 Wiley Periodicals, Inc.