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AIM To investigate the influence of chronological aging on periodontal regenerative therapy (PRT) outcomes with enamel matrix derivative (EMD). MATERIALS AND METHODS In total, 253 intra-bony defects (151 patients) including 44 furcation involvement were prospectively investigated for 3 years after regenerative therapy with EMD by evaluating probing pocket depth (PPD), clinical attachment level (CAL), and radiographic bone defect depth (RBD). The influence of age on these outcomes was assessed using multilevel regression analyses adjusting for confounders. RESULTS Participants' mean age was 55.9 ± 12.3 years (range: 22-85). Baseline PPD, CAL, and RBD were 6.14 ± 1.82, 7.22 ± 2.14, and 5.08 ± 2.04 mm, respectively. Significant improvement was observed with PPD reductions of 2.84 ± 1.73 and 2.87 ± 1.87 mm, CAL gains of 2.40 ± 1.87 and 2.47 ± 1.89 mm, and RBD gains of 1.76 ± 1.98 and 2.39 ± 2.41 mm at 1- and 3-year examinations, respectively. At the 1-year examination, multivariate analysis revealed a significant negative association between age and improvement in PPD and CAL (coefficients: -0.13, -0.23 mm per 10 years). However, by the 3-year examination, no significant association was noted between age and improvement in PPD, CAL, or RBD. CONCLUSION Although the statistical difference was detected with age at 1-year examination, PRT with EMD significantly improved clinical outcomes on long-term observation, irrespective of the patient's age. CLINICAL TRIAL REGISTRATION NUMBER UMIN000039846.

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). 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. 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

The present study discusses the effects of stability control for multi-articulated vehicles on the lane-keeping performance. Vector follower control (VFC) compensates the direction difference angle...

Objective: The aim of this study was to examine effects of recently developed ultraviolet light-emitting diodes (UV LEDs) wavelengths on in vitro growth and gene expression of cultural per...

Porphyromonas gingivalis is a key pathogen in microbiota associated with periodontitis. The purpose of the present study was to assess the association between salivary counts of red-complex bacteria and clinical periodontal status in a Japanese population METHODS: A total of 977 subjects who visited a general dental clinic in Japan from 2003 to 2006 were enrolled in the study. Stimulated saliva was obtained and the amounts of major periodontal bacteria were measured using real-time polymerase chain reaction. Probing pocket depth (PPD), bleeding on probing (BOP), and each subject's average proximal bone crest level (BCL) on dental radiographs were measured RESULTS: The number of P. gingivalis strongly associated with percentage of 4 mm or more PPD sites, BOP positive percentage, and 1.5 mm or more BCL sites. The detection of P. gingivalis with Treponema denticola and/or Tannerella forsythia showed a high rate of three positive clinical parameters, whereas the only P. gingivalis detected group and those without P. gingivalis had a low rate of three positive clinical parameters CONCLUSION: Among red-complex bacteria, the amount of P. gingivalis showed the strongest association with the severity of periodontal condition, and co-occurrence of P. gingivalis with T. denticola and/or T. forsythia showed heightened progression of periodontitis. This article is protected by copyright. All rights reserved.

Objective: This study evaluated the comprehensive and sequential gene expression in laser-ablated bone compared with that in nontreated control bone. Background: Bone ablation by Er:YAG laser has s...

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.

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.

The aim of this study is to analyze the relationship between Hepatocyte Growth Factor (HGF) levels in oral rinses using water and clinical parameters of periodontitis; and furthermore, to evaluate the potential of a prototype HGF immunochromatographic paper test strip (HGF-TS) for screening of periodontitis, in comparison with a commercially-available occult blood (hemoglobin) test strip (Hb-TS). Clinical periodontal parameters were recorded, and oral rinses were collected, from 125 subjects. Then, the presence of HGF, and hemoglobin (Hb), in each sample was detected using a prototype HGF-TS and an Hb-TS. In addition, the concentrations of HGF and Hb were also determined in each sample is necessary HGF concentrations in oral rinses showed significant correlations with clinical parameters of periodontitis. The positive rate and read value on HGF-TS showed significantly high values in cases of severe periodontitis compared to healthy subjects. Hb-TS showed generally higher positive rates than HGF-TS; however, it showed false positive results in healthy subjects. The concentration of HGF in oral rinses showed close association with the severity of periodontitis, suggesting that the prototype HGF-TS has potential for use in the diagnosis of periodontitis, although further refinement of the test strip is required to increase the sensitivity.

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.

Considering the water cooling system in fusion reactors, there are several fusion-specific challenges in designs of in-vessel components and their cooling water systems (CWS). In this research, solutions of the challenges have been discussed and indicate the CWS concept of Japan's DEMO. The CWS transfers thermal energy of blanket and a part of divertor to a generator system, and thermal energy of the other part of divertor is used as heat utilization in plant. The required performance of system devices such as pumps is expected to be achieved by proven technologies and its extensions. It is also indicated that blanket can work as the low-pass filter, and can suppress the effect of fusion output fluctuation. The designed cooling water system requires 70 MW electric power and generates 620 MW power with a 1.5 GW fusion power plasma. This research indicates the basic concept of Japan's DEMO CWS that can be practically achieved.

This study evaluated the effectiveness of swept-source optical coherence tomography (ss-OCT) for detecting calculus and root cementum during periodontal therapy. Optical coherence tomography (OCT) images were taken before and after removal of subgingival calculus from extracted teeth and compared with non-decalcified histological sections. Porcine gingival sheets of various thicknesses were applied to the root surfaces of extracted teeth with calculus and OCT images were taken. OCT images were also taken before and after scaling and root planing (SRP) in human patients. In vitro, calculus was clearly detected as a white-gray amorphous structure on the root surface, which disappeared after removal. Cementum was identified as a thin, dark-gray layer. The calculus could not be clearly observed when soft tissues were present on the root surface. Clinically, supragingival calculus and cementum could be detected clearly with OCT, and subgingival calculus in the buccal cervical area of the anterior and premolar teeth was identified, which disappeared after SRP. Digital processing of the original OCT images was useful for clarifying the calculus. In conclusion, ss-OCT showed potential as a periodontal diagnostic tool for detecting cementum and subgingival calculus, although the practical applications of subgingival imaging remain limited.

This large-scale study cross-sectionally examined the periodontal status and prevalence of "red complex" bacteria (Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia) in Japanese adults. A total of 977 participants were enrolled in the study. Probing depth (PD), bleeding on probing (BOP), and bone crest level (BCL) were recorded, and the presence of red complex bacteria in the saliva was examined using polymerase chain reaction. The mean BCL value and the percentage of sites with a PD ≥4 mm or the presence of BOP were significantly higher in older participants. The detection rates of P. gingivalis, T. denticola, and T. forsythia were 46.3%, 76.4%, and 61.1%, respectively. The P. gingivalis detection rate significantly increased with age, while those of T. denticola and T. forsythia were comparably high for all age groups. A close correlation between P. gingivalis and the percentage of sites with PD ≥4 mm was indicated by nonlinear canonical correlation analysis. Current smokers exhibited a more advanced disease condition and a significantly higher P. gingivalis detection rate than non-smokers. In conclusion, periodontal condition worsens with age, and P. gingivalis appears to be the red complex bacterium most closely associated with periodontitis.

Periodontitis is an inflammatory disease characterized by the destruction of the periodontium. In the last decade, a new murine model of periodontitis has been widely used to simulate alveolar bone resorption and periodontal soft tissue destruction by ligation. Typically, 3-0 to 9-0 silks are selected for ligation around the molars in mice, and significant bone loss and inflammatory infiltration are observed within a week. The ligature-maintained period can vary according to specific aims. We reviewed the findings on the interaction of systemic diseases with periodontitis, periodontal tissue destruction, the immunological and bacteriological responses, and new treatments. In these studies, the activation of osteoclasts, upregulation of pro-inflammatory factors, and excessive immune response have been considered as major factors in periodontal disruption. Multiple genes identified in periodontal tissues partly reflect the complexity of the pathogenesis of periodontitis. The effects of novel treatment methods on periodontitis have also been evaluated in a ligature-induced periodontitis model in mice. This model cannot completely represent all aspects of periodontitis in humans but is considered an effective method for the exploration of its mechanisms. Through this review, we aimed to provide evidence and enlightenment for future studies planning to use this model.

Background and Objective Diagnosis is a crucial step in periodontal treatment. The aim of this study was to evaluate the effectiveness of optical coherence tomography (OCT) for observation and determination of periodontal tissue profiles in vivo. Material and Methods In experiment 1, refractive indices of purified water, porcine gingiva and human gingiva at 1330 nm were determined for the analysis of OCT images of periodontal tissues. In experiment 2, OCT examination was performed in the midlabial apico-coronal plane of mandibular anteriors in 30 Asian volunteers with healthy gingiva. Sulcus depth was measured on intra-oral photographs taken during probing. In the OCT images, the gingival, epithelial and connective tissue thickness, and the position of alveolar bone crest were determined and finally, the biologic width was measured. Results Refractive indices of purified water, porcine gingiva and human gingiva were 1.335, 1.393 and 1.397, respectively. Cross-sectional images of gingival epithelium, connective tissue and alveolar bone were depicted in real-time. The sulcular and junctional epithelium could be visualized occasionally. Laser penetration and reflection were limited to a certain depth with an approximate maximal imaging depth capability of 1.5 mm and OCT images of the periodontal structure were not clear in some cases. The average maximal thickness of gingiva and epithelium and biologic width at the mandibular anteriors were 1.06 ± 0.21, 0.49 ± 0.15 and 2.09 ± 0.60 mm, respectively. Conclusion OCT has promise for non-invasive observation of the periodontal tissue profile in detail and measurement of internal periodontal structures including biologic width in the anterior region.

Periodontitis is a chronic inflammatory disease that affects the interface of teeth and surrounding tissues. Gingival crevicular fluid (GCF) is an exudate of the periodontal tissues and can be collected from the gap between the tooth and gum (gingival sulcus or periodontal pocket) with paper strips. Testing of GCF is a low‐cost and minimally invasive procedure. In a variety of diseases, microRNAs (miRNAs) in body fluids are implicated in pathogenesis, and are suggested as potential diagnostic biomarkers. Here, we profiled miRNAs in GCF (two chronic periodontitis, one aggressive periodontitis, and five healthy subjects) using miRCURY LNA™ Universal RT microRNA PCR System, which yielded quantitative measures of more than 600 miRNAs. Through this analysis, we found that miRNA profiles in GCF of periodontitis patients are distinct from those of healthy controls. We further selected 40 miRNAs and confirmed their differential expression patterns in different subjects (five chronic periodontitis, one aggressive periodontitis, and six healthy subjects) using a custom miRNA PCR panel. This is the first demonstration of miRNA profiling in GCF and its alteration in periodontitis. Our findings suggest that a subset of miRNAs in GCF holds potential as a biomarker for periodontitis.

(Part 2 of this article can be located at www.liebertpub.com/doi/10.1089/photob.2019.4731.) Objective: Finding evidence-based treatment strategies for low-level light therapy (LLLT) and the correct incorporation of these treatment methods in the clinical practice of periodontics. Background: Photobiomodulation has been shown to have biostimulatory, anti-inflammatory and analgesic effects that can be beneficial in periodontal and dental implant treatment procedures. Methods: In this review we have addressed some clinical questions regarding the potential clinical application of low-level light irradiation and its photobiomodulatory effects in periodontology and implantology. The literature was searched for in vivo (animal or clinical) articles written in English in four electronic databases of PubMed, Scopus, Google Scholar, and Cochrane Library until April 2019. Only studies with low irradiation doses without any thermal effects used only for their photobiomodulatory purposes were included. Results: We were able to find relevant studies for all of our questions, and positive effects for the application of light therapy were reported in most of the studies. However, there is still great deal of heterogeneity in terms of study designs and most importantly in light irradiation devices and the parameters used. Owing to this issue it was not possible to reach specific evidence-based irradiation protocols for the questions addressed in this review. Conclusions: Based on our search results, an obvious positive effect of LLLT on stimulation of healing of periodontal soft and hard tissues and reduction of inflammation can be seen. Future well-designed randomized control studies with the same irradiation settings and systematic reviews evaluating the studies found on the questions mentioned are necessary to reach evidence-based recommendations.

Background and Objective This study aimed to evaluate the effects of high-frequency pulsed (HiFP) low-level laser therapy (LLLT) on early wound healing of tooth extraction sockets in rats. Study Design/Materials and Methods Bilateral maxillary first molars were extracted from 6-week-old Sprague-Dawley rats. Sockets on the right were treated by HiFP low-level diode laser irradiation (904–910 nm); the left sides served as unirradiated controls. LLLT (0.28 W, 30 kHz, 200-ns pulse, 0.6% duty cycle, 61.2 J/cm2 total power density) was employed immediately after extraction and every 24 hours thereafter. The maxillae including the sockets were resected 3 or 7 days after extraction. Soft-tissue healing was evaluated on days 0, 3, and 7. The bone mineral content (BMC), bone volume (BV), and bone mineral density (BMD) of the extraction sockets were evaluated by microcomputed tomography, and histomorphometric analysis was carried out on day 7. Real-time PCR analysis of osteogenic marker expression and immunohistochemical detection of proliferating cell nuclear antigen (PCNA)-positive cells were performed on day 3. Results Compared with control sites, the un-epithelialized areas of the extracted sites were significantly reduced by irradiation (P = 0.04), and the BMC, BV, and BMD of laser-treated sites were significantly increased (P = 0.004, 0.006, and 0.009, respectively). On day 7, the mean height of newly formed immature woven bone was higher in laser-treated sites (P = 0.24). On day 3, laser-treated sites showed significantly higher osteocalcin mRNA expression (P = 0.04) and PCNA-positive cell numbers (P = 0.01). Conclusion HiFP low-level diode laser irradiation enhanced soft- and hard-tissue healing of tooth extraction sockets. Lasers Surg. Med. 48:955–964, 2016. © 2016 Wiley Periodicals, Inc.

The objective of this study was to evaluate an Er:YAG laser (ErL) application for periodontal regenerative surgery in angular bone defects at nine sites in six patients. Debridement was thoroughly performed using a combination of curettage with a Gracey-type curette and ErL irradiation at a panel setting of 70 mJ/pulse and 20 Hz with sterile saline spray. After applying an enamel matrix derivative and autogenous bone grafting, ErL was used to form a blood clot coagulation on the grafted bone surface at 50 mJ/pulse and 20 Hz without water spray for approximately 30 seconds. Twelve months after surgery the mean probing depth had improved from 6.2 mm to 2.0 mm, the mean clinical attachment level had reduced from 7.5 mm to 3.4 mm, and bleeding on probing had improved from (+) to (-). Mean intrabony defect depth decreased from 6.0 mm before surgery to 1.0 mm 12 months after surgery. A novel procedure for periodontal regenerative surgery applying ErL irradiation for thorough decontamination during debridement as well as blood coagulation following autogenous bone grafting seems to have achieved favorable and stable healing of periodontal pockets with significant clinical improvement and desirable regeneration of angular bone defects, including one-wall defects.

Background and Objective Mid-infrared erbium: yttrium-aluminum-garnet (Er:YAG) and erbium, chromium: yttrium-scandium-gallium-garnet (Er,Cr:YSGG) lasers (2.94- and 2.78-μm, respectively) are utilized for effective dental hard tissue treatment because of their high absorption in water, hydroxide ion, or both. Recently, a mid-infrared tunable, nanosecond pulsed, all-solid-state chromium-doped: cadmium-selenide (Cr:CdSe) laser system was developed, which enables laser oscillation in the broad spectral range around 2.9 μm. The purpose of this study was to evaluate the ablation of dental hard tissue by the nanosecond pulsed Cr:CdSe laser at a wavelength range of 2.76–3.00 μm. Study Design/Materials and Methods Enamel, dentin, and cementum tissue were irradiated at a spot or line at a fluence of 0–11.20 J/cm2/pulse (energy output: 0–2.00 mJ/pulse) with a repetition rate of 10 Hz and beam diameter of ∼150 μm on the target (pulse width ∼250 ns). After irradiation, morphological changes, ablation threshold, depth, and efficiency, and thickness of the structurally and thermally affected layer of irradiated surfaces were analyzed using stereomicroscopy, scanning electron microscopy (SEM), and light microscopy of non-decalcified histological sections. Results The nanosecond pulsed irradiation without water spray effectively ablated dental hard tissue with no visible thermal damage such as carbonization. The SEM analysis revealed characteristic micro-irregularities without major melting and cracks in the lased tissue. The ablation threshold of dentin was the lowest at 2.76 μm and the highest at 3.00 μm. The histological analysis revealed minimal thermal and structural changes ∼20 μm wide on the irradiated dentin surfaces with no significant differences between wavelengths. The efficiency of dentin ablation gradually increased from 3.00 to 2.76 μm, at which point the highest ablation efficiency was observed. Conclusion The nanosecond pulsed Cr:CdSe laser demonstrated an effective ablation ability of hard dental tissues, which was remarkably wavelength-dependent on dentin at the spectral range of 2.76–3.00 μm. These results demonstrate the potential feasibility of the use of pulsed Cr:CdSe laser as a novel laser system for dental treatment. Lasers Surg. Med. © 2016 Wiley Periodicals, Inc.

We have developed a mid-infrared (mid-IR) tunable Cr:CdSe laser with nanosecond pulse operation. A broad tuning range from 2.25 to 3.08 µm and an output energy exceeding 4 mJ at 2.64 μm were demonstrated. The maximum energy conversion for absorbed energy reached 35% when the pump fluence was 2.1 J/cm2. We showed that Cr:CdSe is an attractive laser material for obtaining high-energy pulses in the mid-IR region and that the Cr:CdSe laser has high potential for laser biomaterial processing.

Background For treatment of advanced elbow osteochondritis dissecans (OCD), we have used surgical treatment. Although favorable treatment outcomes have been reported for centrally located OCD, treatment outcomes are generally questionable and the choice of surgical method is controversial for laterally located OCD. Our purpose was to evaluate the treatment outcomes based on lesion location. Methods The patients were 30 young (mean age, 14 years) male athletes who underwent surgical treatment of elbow OCD and were monitored for more than 1 year. Osteochondral autografts harvested from the knee were transplanted to centralized (13 patients) or lateral localized (9 patients) OCD lesions. For lateral widespread (8 patients) OCD lesions, a detached osteochondral fragment was fixed using small osteochondral plugs. When the remaining cartilage defect was large after fragment fixation, a large-sized osteochondral plug was transplanted to the defect. Treatment outcomes were evaluated by the Japanese Orthopaedic Association score, elbow range of motion (ROM), and radiographic findings. Results The Japanese Orthopaedic Association score significantly improved in patients with centralized, lateral localized, and lateral widespread types of OCD. ROM significantly improved in patients with centralized and lateral localized, and they returned to playing sports within 6 months. However, patients with lateral widespread OCD exhibited no significant ROM improvement, and returning to sports was difficult for 3 patients because of poor osseous integration of the fixed osteochondral fragment. Conclusions Osteochondral autograft transplantation provided favorable outcomes for centralized and lateral localized elbow OCD lesions. However, for lateral widespread OCD lesions, reconstruction of the entire capitellar lesion area may be necessary.

Antimicrobial photodynamic therapy (PDT) has attracted much attention for the treatment of pathogenic biofilm associated with peridontitis and peri-implantitis. However, data from randomized controlled clinical studies (RCTs) are limited and, to some extent, controversial, making it difficult to provide appropriate recommendations. Therefore, the aims of the present study were (a) to provide an overview on the current evidence from RCTs evaluating the potential clinical benefit for the additional use of PDT to subgingival mechanical debridement (ie, scaling and root planing) alone in nonsurgical periodontal therapy; and (b) to provide clinical recommendations for the use of PDT in periodontal practice.

Laser ablation is recently suggested as a most effective and reliable technique for depigmentation of melanin hyperpigmented gingiva. To date, different lasers have been used for gingival depigmentation (CO2, diode, Nd:YAG, Er:YAG and Er,Cr:YSGG lasers). The use of Er:YAG laser for depigmentation of melanin hyperpigmented gingiva has gained increasing importance in recent years. The purpose of this study was to report removal of gingival melanin pigmentation using an Er:YAG laser in a literature review. The main outcomes, such as improvement of signs (clinical parameters of bleeding, erythema, swelling and wound healing), symptoms (pain) and melanin recurrence/repigmentation were measured. The literature demonstrated that depigmentation of gingival melanin pigmentation can be performed safely and effectively by Er:YAG laser resulting in healing and an esthetically significant improvement of gingival discoloration. Thus, Er:YAG laser seems to be safe and useful in melanin depigmentation procedure. However, the main issue in giving the final conclusion of the optimal Er:YAG laser use in melanin depigmentation is that, to date, studies are offering completely discrepant Er:YAG laser procedure protocols (complex settings of laser parameters), and different criteria for the assessment of depigmentation and repigmentation (recurrence), thus hampering the comparison of the results. Therefore, further studies are necessary to give an optimal recommendation on the use of Er:YAG laser in gingival melanin hyperpigmentation.

Background and Aim Bacterial biofilms play a major role in the etiology of periodontal and peri-implant diseases. The aim of the study was to evaluate the removal of bacterial biofilms and attachment of epithelial cells (EC), gingival fibroblasts (GF) and osteoblast-like cells (OC) to dentin and titanium surfaces after Er:YAG laser (Er:YAG) in comparison with other treatment methods. Material and Methods Multi-species bacterial biofilms were grown on standardized dentin and titanium specimens with a sand-blasted and acid etched (SLA) surface for 3.5 d. Thereafter, the specimens were placed into artificially-created pockets. The following methods for biofilm removal were used: 1) Gracey (dentin) or titanium curettes (CUR), 2) Er:YAG, 3) photodynamic therapy (PDT) and 4) CUR with adjunctive PDT (CUR/PDT). Colony forming units (CFUs) of the remaining biofilms and attachment of EC, GF and OC were determined. Statistical analysis was performed by means of ANOVA with post-hoc LSD. Results All treatment methods decreased statistically significantly (p

The erbium-doped yttrium aluminum garnet (Er:YAG) laser is currently used for periodontal soft tissue management with favorable outcomes. However, the process of wound healing after Er:YAG laser (ErL) treatment has not been fully elucidated yet. The aim of this study was to investigate the gingival tissue healing after ErL ablation in comparison with that after electrosurgery (ElS). Gingival defects were created in 28 rats by ablation with ErL irradiation or ElS. The chronological changes in wound healing were evaluated using histological, histometrical, and immunohistochemical analyses. The ErL-ablated gingival tissue revealed much less thermal damage, compared to the ElS. In the ElS sites, the postoperative tissue destruction continued due to thermal damage, while in the ErL sites, tissue degradation was limited and the defects were re-epithelialized early. Heat shock protein (Hsp) 72/73 expression was detected abundantly remote from the wound in the ElS, whereas it was slightly observed in close proximity to the wound in the ErL sites. Hsp47 expression was observed in the entire connective tissue early in the wound healing and was found limited in the wound area later. This phenomenon proceeded faster in the ErL sites than in the ElS sites. Expression of proliferating cell nuclear antigen (PCNA) persisted in the epithelial tissue for a longer period in the ElS than that in the ErL. The ErL results in faster and more favorable gingival wound healing compared to the ElS, suggesting that the ErL is a safe and suitable tool for periodontal soft tissue management.

The purpose of this study was to investigate the root morphology of teeth and efficiency of scaling after using Er:YAG and Er,Cr:YSGG lasers. Thirty-two periodontally hopeless teeth were extracted. The border of an appropriate calculus was marked using a diamond bur on each tooth, and the calculus was divided into two almost equal parts. An Er,Cr:YSGG laser with pulse energy of 50 mJ, power of 1 W, and energy density of 17.7 J/cm2 and an Er:YAG laser with pulse energy of 200 mJ, power of 2.4 W, and energy density of 21 J/cm2 were used to remove the calculus. The time for scaling was recorded for each group, and using stereomicroscopic analysis, the calculus remnant, carbonization, and number of craters were investigated. The mean time required for calculus removal in the Er,Cr:YSGG and Er:YAG laser groups was 15.22 ± 6.18 seconds and 7.12 ± 4.11 seconds, respectively. The efficiency of calculus removal in the Er:YAG laser group was significantly higher than in the Er,Cr:YSGG laser group. Under stereomicroscope examination, no carbonization or remaining calculus was found in samples from either group, but all samples had craters. The number of craters in the Er,Cr:YSGG laser group was significantly higher than in the Er:YAG laser group. According to the parameters used and limitations of this study, there was no significant difference in efficiency per power for calculus removal between the two groups.

This paper describes an analytical study of the lateral dynamics of multi-articulated vehicles with multiple axles. A linear planar model of vehicle dynamics is adopted for multiple-axle vehicle combinations with an optional number of trailers. Two tractor and double-trailer combinations are examined for their directional stability and response. Non-oscillatory stability and steering sensitivity in steady-state turning and lane changing are analysed using a stability factor of multiple-axle vehicle combinations. Off-tracking in the steady-state turning of multiple-axle vehicle combinations is also analysed. Numerical calculations for oscillatory stability, steering sensitivity, and off-tracking are presented for multiple-axle vehicle combinations.

Objective Treatment of large advanced osteochondritis dissecans (OCD) of the elbow in young athletes is challenging. Methods We retrospectively reviewed the results in 9 baseball players (mean age, 13.7 years; range, 12-15 years) who were followed up for a mean 21.1 months (range, 12-36 months) after osteochondral autograft. In this operation, cylindrical osteochondral plugs were harvested from a lateral femoral condyle and transferred to the lesion in humeral capitellum. After immobilizing the elbow by a splint for 2 weeks, the patients were encouraged to do range of motion exercises using an elbow brace with a hinge for 2 months. The elbow brace was applied to avoid excess stress to the implants on the capitellum and to the lateral collateral ligament. Patients were clinically assessed by the Japanese Orthopaedic Association elbow score (JOA score) and morphologically by radiographs as well as by magnetic resonance imaging (MRI). Results Patients started playing catch at 3 months and returned to baseball at competitive level at around 6 months postoperatively. The average JOA score was 68.0 points before operation and improved to 98.7 points at follow-up. Bony fusion between the implants and host bone was observed radiographically at 3 months. MRI confirmed a durable load-bearing articular surface of the capitellum at 1 year. Conclusions Osteochondral autograft with postoperative rehabilitation using an elbow brace is a reasonable treatment for young athletes with an advanced lesion of OCD of the elbow who desire a relatively quick return to their pre-injury sports activity level.

The steroid hormones synthesized by the male gonads play diverse roles in biological processes. Androgens, the primary hormones produced by the male gonads, are key regulators of fat homeostasis, hence androgen-deprivation therapies often induce obesity. However, the molecular mechanism by which male gonadal dysfunction leads to obesity remains unclear, because results from animal studies regarding fat accumulation in the context of gonadal defects do not reflect clinical findings. Here, we investigated the mechanism underlying the development of obesity in animals with male gonadal dysfunction by analyzing the long-term physiological changes in adult male mice with surgical castration. Nine weeks after surgery, white adipose tissue (WAT) mass was higher in the castrated (Cas) mice than in sham-operated (Sham) mice. In addition, castration induced hyperlipidemia and hyperglycemia. However, genes involved in lipid metabolism, including hormone-sensitive lipase, were unchanged in the adipose tissue of the Cas mice, despite the increase in WAT. In contrast, a hepatic gluconeogenesis gene, glucose-6-phosphatase, was significantly upregulated in the Cas mice than in Sham mice. Our findings suggest that long-term hypogonadism in mice mimics the effects in humans, and a potential molecular basis for the induction of obesity in this model is impairment of hepatic gluconeogenesis.

In 2010, The Committee of Clinical Training Program in Japanese Society for Laser Dentistry held the third educational seminar for safety management in clinical laser dentistry at the 22nd annual meeting of Japanese Society of Laser Dentistry.The purpose of this questionnaire study was to investigate the current status of dental laser applications as well as in clinic safety management. The data was taken from 53 attendants including 45 dentists and 8 dental hygienists.The participants of the seminar showed a high level of satisfaction with the contents of the seminar and expressed their in interests in participating in the future seminar. Sixty-nine percent of the dentists frequently use lasers in clinic, 31% checked lasers before usage and 82% used lasers approved by the ministry of Health, Labor and Welfare of Japan.The types of lasers used were the Er:YAG (24%), CO2 (23%), Diode (16%), Nd:YAG (16%), low-power laser (11%) and Er, Cr:YSGG (7%).The laser was applied to the treatment of hypersensitive dentin, soft tissue surgery, stomatitis, periodontal pocket, dental caries and temporomandibular joint disorders.These results suggested the necessity to hold this kind of seminar periodically.

Periodontitis is an inflammatory disease that leads to the loss of tooth-supporting tissues. Conventional periodontal treatment is generally unable to promote regeneration of the damaged periodontal structures. Recently, several studies have investigated the use of tissue engineering to facilitate predictable periodontal regeneration. This article reviews various technologies related to periodontal tissue engineering. These include bone grafting, guided tissue regeneration, enamel matrix protein derivative, growth factors, stem cell therapy, cell sheet engineering and laser treatment. Studies carried out by this group, and available clinical data, together with the authors own clinical experiences, are discussed. In addition, possible new directions that need to be exploited to make periodontal tissue engineering a clinical success are discussed herein.

This paper presents a theoretical study on the directional stability of multi-articulated vehicles with multiple axles. The vehicle dynamics model is derived in the horizontal plane having degrees of freedom of vehicle side-slipping and yawing. For an equal vertical load of each axle as well as an equal cornering coefficient of each wheel of the multiple axles, the equations of motion can be reduced to ones with a single axle and additional terms that are functions of the number of axles and the distances between them. Two types of tractor and double-trailer combinations with multiple axles are examined with regard to straight running stability as well as steering sensitivity in steady-state turning. Non-oscillatory stability incorporating steering sensitivity is analyzed using the stability factor of multiple-axle vehicle combinations. A parameter study of oscillatory stability and steering sensitivity is conducted, and the following conclusions are drawn. (1) The terms on multiple axles are added in the tractor yawing moment and part of the trailer yawing moment. (2) Multiple-axle vehicles differ from single-axle vehicles in non-oscillatory stability and steering sensitivity. (3) A multiple-axle dolly improves oscillatory stability.

This paper presents theoretical research in the fundamentals on the directional stability and controllability of multi-articulated vehicles. Analyses and numerical calculations are conducted by using models incorporating vehicle side-slipping and yawing. Two vehicle combinations are examined with regard to straight running stability, as well as steering sensitivity and off-tracking in steady-state turning. Type I is a tractor and two semitrailers; type II is a tractor, semitrailer, and full-trailer. The following conclusions are drawn. (1) The criterion of non-oscillatory stability of types I and II is a function of the stability factor as well as that of tractor and semitrailer combinations. (2) Type I is more stable than type II in oscillatory modes. (3) Type I differs slightly from type II regarding non-oscillatory stability, steering sensitivity, and off-tracking in steady-state turning.

Directional response and directional stability of vehicle combinations are main research topics in vehicle safety. This paper analyzes the steering sensitivity in lane-change maneuvers of multi-articulated vehicles with multiple axles using simplified mathematical models. It also calculates the frequency response, pole, and zero in the transfer functions of each variable for two types of tractor-double-trailer, a tractor-semitrailer and a truck-full-trailer having multiple axles. The following conclusions are drawn. (1) The steering sensitivity of multi-articulated vehicles with multiple axles in lane-change maneuvers is composed of steering sensitivity in steady-state turns and the parameters of lane-change maneuvers. (2) The effect of the number of trailer axles on the damping ratio of zero is larger than that of the other parameters for multiple axles. (3) A large steering angle is necessary to change running lanes for multi-articulated vehicles with multiple axles that have low steering sensitivity in lane-change maneuvers; therefore, the rise time is short. Moreover, if the vehicle combination has a low damping ratio of oscillatory modes, the settling time is long, and the overshoot and maximum deviation are large.

Background Despite the recent increase in application of Er:YAG laser for various dental treatments, limited information is available regarding the contact tips. This study examined the changes in energy output and surface condition of quartz and sapphire contact tips after Er:YAG laser contact irradiation for tooth enamel ablation. Materials and Methods Ten sets of unused quartz or sapphire contact tips were employed for contact irradiation to sound enamel of extracted teeth. The teeth were irradiated with Er:YAG laser at approximately 75 J/cm2/pulse and 20 Hz under water spray for 60 minutes. The energy output was measured before and every 5 minutes after irradiation, and the changes in morphology and chemical composition of the contact surface were analyzed. Results The energy output significantly decreased with time in both tips. The energy output from the sapphire tips was generally higher on average than that of the quartz. The contact surfaces of all the used quartz tips were concave and irregular. Most of the sapphire tips also appeared rough with crater formation and fractures, except for a few tips in which a high energy output and the original smooth surface were maintained. Spots of melted tooth substances were seen attached to the surface of both tips. Conclusion In contact enamel ablation, the sapphire tip appeared to be more resistant than the quartz tip. The quartz tips showed similar patterns of energy reduction and surface alteration, whereas the sapphire tips revealed a wider and more characteristic variation among tips. Lasers Surg. Med. 41:595–604, 2009. © 2009 Wiley-Liss, Inc.

Background/Aim. Recurrent aphthous stomatitis (RAS) is defined as multifactor immunologic inflammatory lesions in the oral cavity, characterized by painful, recurrent single/multiple, shallow, round or ovoid ulcerations of mucosal tissues. To date, a considerable number of RAS treatment protocols have been suggested, but since the etiology of RAS is idiopathic, these treatment options have symptomatic rather than curative or preventive effect. Recently, it has been suggested that laser therapy could be successfully used as an efficient treatment approach in therapy of RAS. Therefore, the aim of this review was to estimate the effects of laser therapy in treatment of RAS analyzing results of clinical studies published in peer reviewed journals. Methods. The studies published until 31 December 2013 were obtained from the Medline/PubMed, Science Direct and Cochrane Library of the Cochrane Collaboration (CENTRAL) online databases, using following search terms and key words: “laser” AND “recurrent aphthous stomatitis”, “laser” AND “aphthous”, and “laser” AND “aphthae”. In total 4 original research articles met the all required inclusion/exclusion criteria, and were used for this review. The main outcome measures assessed were: a reduction of pain associated with RAS and a reduction in episode duration (faster RAS healing). Results. The assessed literature demonstrates the benefits of laser therapy mainly due to immediate analgesia and ability to speed up a RAS healing process. Conclusion. Even though the assessed literature suggests beneficial outcomes of laser therapy in treatment of RAS, these results should be interpreted with caution. The issues related to the study designs and different sets of laser irradiation parameters of a limited number of available studies with the same treatment outcomes prevent us from making definite conclusions.