The effect of combination treatment of CO2-laser irradiation and tetracalcium phosphate/dicalcium phosphate anhydrate on dentinal tubules blockage: an in vitro study.

The aim of this study was the evaluation of the in vitro efficacy of a carbon dioxide (CO2) laser, a tetracalcium phosphate/dicalcium phosphate anhydrate (TP/DP) desensitizer and the combination of the desensitizer and additional CO2 laser irradiation as a treatment modality for cervical dentin hypersensitivity. A total of 48 dental specimens, prepared from extracted human premolars and molars, were divided into four groups: a control group, a TP/DP desensitizer paste group, a CO2 laser (10.600-nm wavelength) group, and a paste and laser group. The specimens were coated with nail varnish except in the marked area and were then immersed in 2% methylene blue dye for 1 h. The specimens were then washed, dried, and cut longitudinally. Thereafter, photos of 40 dentin specimens were taken and evaluated. The area of penetration was assessed and reported as percentage of the dentin surface area. Additionally eight dental specimens were examined with the aid of a scanning electron microscope and evaluated. Significant differences in the penetration depth were found for all experimental groups compared to the control group. The lowest penetration area was detected in the paste-laser group (16.5%), followed by the laser (23.7%), the paste (48.5%), and the control group (86.2%). The combined treatment of the CO2 laser and a TP/DP desensitizer was efficient in sealing the dentinal surface and could be a treatment option for cervical dentin hypersensitivity.

Effects of enamel matrix derivative in nonsurgical periodontal therapy on pro-inflammatory profiles, microbial environment and clinical outcome: a randomized clinical trial.

OBJECTIVES: This study aimed to evaluate the impact of enamel matrix derivative (EMD) application following subgingival instrumentation of residual pockets in periodontitis patients on inflammatory host response, microbiological composition, and clinical outcome. METHODS: In this double-blinded randomized controlled trial, a total of 22 patients with generalized periodontitis stage III or IV presenting with ≥ 6 mm probing pocket depth (PPD) at re-evaluation after initial periodontal therapy were included. Participants were randomly allocated at a 1:1 ratio to subgingival instrumentation with (EMD +) or without (EMD-) non-surgical EMD application into the pocket. PPD, clinical attachment level (CAL), bleeding on probing (BoP), plaque index (PI), as well as a panel of pro-inflammatory cytokines and periodontal pathogen count in the gingival crevicular fluid (GCF) of the respective sites were evaluated at baseline (T0) and six months afterwards (T1). RESULTS: Both treatment groups showed a significant PPD reduction (EMD + 1.33 ± 1.15 mm, p < 0.001; EMD- 1.32 ± 1.01 mm, p < 0.001) as well as CAL gain (EMD + 1.13 ± 1.58 mm, p < 0.001; EMD- 0.47 ± 1.06 mm, p = 0.005) from T0 to T1. While no intergroup differences for PPD reduction were observed, CAL gain was higher in EMD + sites compared to EMD- (p = 0.009). No essential effects on cytokine expression as well as bacterial count were detected. CONCLUSIONS: Application of EMD as an adjunct to subgingival instrumentation of residual pockets yielded benefits regarding CAL gain; however, effects on PPD reduction, inflammatory cytokines, and bacterial count were negligible. TRIAL REGISTRATION: ClinicalTrials.gov (NCT04449393), registration date 26/06/2020. CLINICAL RELEVANCE: Based on the obtained results, additional non-surgical EMD application compared to subgingival instrumentation alone showed no clinically relevant effects on treatment outcome and underlying biological mechanisms.

Effect of interdental brush design on plaque during nonsurgical periodontal therapy.

OBJECTIVE: The aim of this randomized controlled trial was to evaluate the interproximal cleaning efficacy of waist-shaped compared with straight soft interdental brushes in patients undergoing nonsurgical periodontal therapy. MATERIALS AND METHODS: Ten patients diagnosed with periodontitis stage II or III were scheduled for nonsurgical periodontal therapy. Baseline plaque control record (PCR), modified approximal plaque index (API), papillary bleeding index (PBI), probing pocket depth (PPD), and bleeding on probing (BOP) were evaluated. Four interdental spaces of equal sizes were determined, and baseline plaque indices (PI) were assessed on eight surfaces of the respective adjacent teeth, resulting in 640 measuring positions. Interdental brushes with a straight or waist-shaped design were randomly allocated to the right or left side, and patients received oral hygiene instructions. Follow-up measurements including PCR, API, PBI, and site-specific PI were performed during initial nonsurgical periodontal therapy sessions and reevaluation which was undertaken 8 weeks afterwards. RESULTS: PCR, API, and PBI decreased significantly compared with baseline at each time point (p < 0.001). PPD (waist-shaped, baseline 4 mm (range, 2-9 mm) vs. reevaluation 3 mm (range, 1-6 mm); p < 0.001; straight, baseline 4 mm (range, 2-10) vs. reevaluation 3 mm (range, 1-6) mm; p < 0.001) and BOP (p = 0.008) showed significant reduction in both groups. Sub-analysis of site-specific areas including line angles and interproximal areas revealed no significant reduction of plaque during the observation period between both brush designs. No difference between straight and waist-shaped brushes regarding PPD or BOP decrease was found. CONCLUSION: The efficacy of both interdental brush designs concerning plaque control in patients undergoing nonsurgical periodontal therapy was similar. CLINICAL RELEVANCE: The use of interdental brushes is essential for biofilm removal in patients during initial periodontal therapy, regardless of brush design. CLINICAL TRIAL REGISTRATION: ISRCTNregistry (#ISRCTN24498365), http://www.isrctn.com/ISRCTN24498365.

Short-term results of the combined application of neodymium-doped yttrium aluminum garnet (Nd:YAG) laser and erbium-doped yttrium aluminum garnet (Er:YAG) laser in the treatment of periodontal disease: a randomized controlled trial.

OBJECTIVES: Nd:YAG and Er:YAG lasers have been previously used as an adjunct in periodontal therapy. The aim of this single-blinded randomized controlled clinical trial was to evaluate the efficacy of a combined application of Nd:YAG and Er:YAG laser irradiation in periodontal treatment. MATERIALS AND METHODS: Twenty-two patients with at least one site of ≥ 6 mm periodontal probing depth (PPD) after mechanical debridement with curettes and sonic instruments at periodontal reevaluation were included in the study. Patients were randomly allocated at a 1:1 ratio to either a combined Nd:YAG/Er:YAG laser therapy (test group) or a "turned off" laser therapy (control group). The Nd:YAG laser was used for periodontal pocket deepithelialization and to stabilize the resulting blood clot. The Er:YAG laser was primarily used for root surface modification. PPD (mm), clinical attachment level (CAL, mm), and bleeding on probing (BOP, +/-) at the site of laser treatment were evaluated at baseline and 2 months after treatment. RESULTS: The mean improvements from baseline to 2-month follow-up for PPD were significantly better in the laser group (2.05 ± 0.82 mm) compared to the control group (0.64 ± 0.90 mm; p = 0.001). Likewise, the gain in CAL was significantly better in the laser group (1.50 ± 1.10 mm) than in the control group (0.55 ± 1.01mm; p = 0.046). CONCLUSIONS: The combined application of Nd:YAG and Er:YAG laser irradiation as an adjunct to conventional non-surgical therapy showed a significant beneficial effect on periodontal treatment results. CLINICAL RELEVANCE: Combined Nd:YAG and Er:YAG laser irradiation could be a useful procedure additionally to conventional non-surgical periodontal therapy to improve periodontal treatment results. CLINICAL TRIAL REGISTRATION: ISRCTN registry #ISRCTN32132076.

Effect of a multinutrient supplement as an adjunct to nonsurgical treatment of periodontitis: A randomized placebo-controlled clinical trial.

BACKGROUND: The aim of this double-blind randomized placebo-controlled clinical trial was to evaluate the efficacy of a multinutrient supplement as an add-on therapy to scaling and root planing for patients with periodontitis. METHODS: Forty-two patients with stage III or IV periodontitis were randomly allocated to a 2-month treatment of either a multinutrient supplement containing vitamin C, vitamin E, zinc, selenium, alpha-lipoic-acid, cranberry extract, grapeseed extract, and coenzyme Q10 or placebo capsules as an adjunct to conservative periodontal therapy. Periodontal parameters, including probing pocket depth, gingival recession, bleeding on probing, approximal plaque index, and papillary bleeding index, were assessed. Clinical attachment loss, periodontal inflamed surface area, periodontal epithelial surface area, and percentages of pocket sites with ≤3, ≤4, ≥5, ≥6, ≥7, and ≥4 mm with bleeding on probing were calculated. RESULTS: All clinical parameters significantly improved from baseline to reevaluation within each group (p < 0.05). Multinutrient intake resulted in a significantly higher reduction of probing-pocket-depth (-0.75 ± 0.42 mm) and bleeding-on-probing (-21.9 ± 16.1%) from baseline to reevaluation compared with placebo (-0.51 ± 0.30 mm, p = 0.040 and -12.5 ± 9.8%, p = 0.046, respectively). All periodontal parameters showed insignificantly higher improvements in patients receiving the supplement compared with those receiving the placebo (p > 0.05). CONCLUSIONS: Multinutrient supplementation as an adjunct to nonsurgical treatment of periodontitis showed some additional benefit regarding probing-pocket-depth and bleeding-on-probing. However, the clinical relevance needs to be further explored.

Quercetin in the Prevention of Induced Periodontal Disease in Animal Models: A Systematic Review and Meta-Analysis.

BACKGROUND: Periodontitis is an inflammatory condition initiated by oral bacteria and is associated with several systemic diseases. Quercetin is an anti-inflammatory and anti-bacterial poly-phenol present in various foods. The aim of this meta-analysis was the evaluation of the effects of quercetin administration in animal models of experimental periodontitis. METHODS: A systematic search was performed in electronic databases using the following search terms: "periodontitis" or "periodontal disease" or "gingivitis" and "quercetin" or "cyanidanol" or "sophoretin" or "pentahydroxyflavone". In vivo preclinical animal models of experimental periodontal disease with a measurement of alveolar bone loss were included in the analysis. The risk of bias of the included studies was assessed using the SYRCLE tool. RESULTS: The systematic search yielded 335 results. Five studies were included, four of them qualified for a meta-analysis. The meta-analysis showed that quercetin administration decreased alveolar bone loss (τ2 = 0.31, 1.88 mm 95%CI: 1.09, 2.67) in experimental periodontal disease animal models. However, the risk of bias assessment indicated that four SYRCLE domains had a high risk of bias. CONCLUSIONS: Quercetin diminishes periodontal bone loss and prevents disease progression in animal models of experimental periodontal disease. Quercetin might facilitate periodontal tissue hemostasis by reducing senescent cells, decreasing oxidative stress via SIRT1-induced autophagy, limiting inflammation, and fostering an oral bacterial microenvironment of symbiotic microbiota associated with oral health. Future research will show whether and how the promising preclinical results can be translated into the clinical treatment of periodontal disease.

Optimized Erbium-Doped Yttrium Aluminum Garnet (Er:YAG) Laser Parameters for the Removal of Dental Ceramic Restorations.

OBJECTIVES: The use of lasers for debonding adhesively luted ceramic restorations is a rather recent oral laser application in dentistry. The removal of all-ceramic restorations in the mouth can often be a troublesome task. A novel method for the debonding of ceramic restorations without damaging the restorations is Er:YAG laser irradiation. The aim of this study was to evaluate the Er:YAG laser for debonding procedures of different dental ceramics and to identify appropriate laser settings. MATERIAL AND METHODS: Lithium disilicate, zirconium-reinforced lithium silicate, feldspatic ceramic, and zirconium dioxide were investigated. Ten ceramic rectangular-shaped specimens with 1 and 2 mm thickness were produced from each material. All specimens were irradiated with four different power settings 1.5; 2.5; 3.5; 4.5 W, pulse duration 50 µs, laser repetition rate 10 Hz, time of irradiation 10 s. The transmitted energy was measured with a powermeter. Additionally the suitability of the Er:YAG laser to remove the adhesively bonded ceramic and the time until loss of retention was evaluated. RESULTS: The transmission rate for 1 and 2 mm platelets was determined for zirconium-reinforced lithium silicate at 54.6%/35.6%, lithium disilicate at 53.2%/35.7%, zirconium dioxide at 40.6%/32.4%, and for the feldspathic ceramic at 19.4%/10.1%. For zirconium-reinforced lithium silicate and zirconium dioxide 2.5 W (250 mJ/10 Hz) was an appropriate energy level for effective debonding. Whereas for lithium disilicate and for feldspathic ceramic, 4.5 W (450 mJ/10 Hz) is required for efficient debonding. CONCLUSIONS: There are differences regarding transmission rates between ceramic types for the Er:YAG laser light and additionally depending on the type of ceramic different energy settings should be used for adequate debonding. Based on our in-vitro experiments we recommend 2.5 W for zirconium-reinforced lithium silicate and zirconium dioxide and 4.5 W for lithium disilicate and feldspatic ceramic. Transmission rates of different ceramic types and varying influences of thicknesses and bonding materials should be considered to adjust the laser parameters during laser debonding of adhesively luted all-ceramic restorations.

A Novel Quantitative Method for Tooth Grinding Surface Assessment Using 3D Scanning.

Sleep bruxism is an oral parafunction that involves involuntary tooth grinding and clenching. Splints with a colored layer that gets removed during tooth grinding are a common tool for the initial diagnosis of sleep bruxism. Currently, such splints are either assessed qualitatively or using 2D photographs, leading to a non-neglectable error due to the 3D nature of the dentition. In this study we propose a new and fast method for the quantitative assessment of tooth grinding surfaces using 3D scanning and mesh processing. We assessed our diagnostic method by producing 18 standardized splints with 8 grinding surfaces each, giving us a total of 144 surfaces. Moreover, each splint was scanned and analyzed five times. The accuracy and repeatability of our method was assessed by computing the intraclass correlation coefficient (ICC) as well reporting means and standard deviations of surface measurements for intra- and intersplint measurements. An ICC of 0.998 was computed as well as a maximum standard deviation of 0.63 mm2 for repeated measures, suggesting an appropriate accuracy of our proposed method. Overall, this study proposes an innovative, fast and cost effective method to support the initial diagnosis of sleep bruxism.

Effectiveness of a 655-nm InGaAsP diode laser to detect subgingival calculus in patients with periodontal disease.

BACKGROUND: Previous in vitro studies have proven laser fluorescence measurement using a 655-nm Indium Gallium Arsenide Phosphide (InGaAsP) based diode laser radiation to be a useful tool to detect subgingival calculus. The aim of this prospective study was to evaluate the 655-nm InGaAsP diode laser in detecting subgingival calculus in patients with periodontal disease compared with photographic assessment during periodontal surgery. METHODS: Twelve patients (six women, six men) aged between 21 and 75 years with periodontitis scheduled for periodontal surgery were included in this prospective study. All laser fluorescence measurements were made before periodontal surgery. Intraoperatively a mucoperiostal flap was performed, subgingival calculus was visualized, and photographic images were taken. The presence of calculus was recorded for each evaluated site. RESULTS: A total of 115 tooth surface sites of 32 teeth from the 12 patients were evaluated before (laser) and during surgery (image). Compared with image evaluation the laser assessment showed a sensitivity of 0.70 (CI0.025 0.53 to CI0.975 0.83) and a specificity of 0.97 (CI0.025 0.85 to CI0.975 0.99). The overall probability to correctly detect subgingival calculus with the laser (accuracy) was 0.82 (CI0.025 0.74 to CI0.975 0.88). CONCLUSIONS: The 655-nm diode laser was able to detect subgingival calculus. Hence, the 655 nm diode laser may be used as an additional tool for calculus detection in non-surgical periodontal therapy.

Patterns of congenitally missing teeth of non-syndromic and syndromic patients treated at a single-center over the past thirty years.

OBJECTIVES: Literature regarding congenitally-missing-teeth (CMT) is lacking especially on CMT-patterns. Thus, the aim of this study was to present an in-depth analysis of 843 patients with CMT treated at a single-center over the past thirty years. DESIGN: Age, date-of-birth-year, gender, medical- and family-history, CMT-types, -numbers, -severity, -region, -symmetry, -patterns using the tooth agenesis code (TAC), and -growth types of all clinically and radiographically diagnosed CMT-patients were collected. Age and occurrence of syndromes were used to divide CMT-patients into non-syndromic patients older than nine years (group1) and syndromic CMT-patients (group2). Groups were compared especially regarding gender and CMT-severity. RESULTS: The average CMT-number per patient was 5.5 (group1, n = 816, 59.9% female) and 15.1 (group2, n = 27, 29.6% female). There were significant less male (40.1% vs. 70.4%, respectively; P = 0.002) as well as significantly less male-oligodontia (44.8% vs. 73.9%, respectively; P = 0.009) in group1 than in group2. Group1 resulted in decreased prevalence of similar CMT-patterns with severity; the most prevalent CMT was the 2nd premolar; there were no significant differences between the right and left side, whereas more CMT affected the maxilla; the majority of patients presented with bilateral-CMT (82.8%); females were more affected by CMT but more males had severer forms; certain single CMT differed by gender, and CMT was related to first-grade-relatives. CONCLUSION: The majority of CMT-patients presented with hypodontia. Furthermore, same CMT-patterns seem more like to be present in patients with milder forms of tooth agenesis. Gender-specific association regarding CMT-number, severity groups, and single CMT were detected.

Suture wear particles cause a significant inflammatory response in a murine synovial airpouch model.

BACKGROUND: Commonly used contemporary orthopaedic sutures have been identified as a potential causative factor in the development of post-arthroscopic glenohumeral chondrolysis. Currently, little is known about the body's immune response to these materials. The aim of this study was to examine the biological response of synovial tissue to three commonly used orthopaedic sutures, using a murine airpouch model. METHODS: Fifty rats were used in this study (ten per group). An airpouch was created in each rat, and test materials were implanted. Test materials consisted of an intact polyethylene terephthalate suture with a polybutilate coating (suture A), an intact polyethylene suture braided around a central polydiaxannone core (suture B), an intact polyethylene/polyester cobraid suture with a silicone coating (suture C), and particles of suture C (particles C). Rats were sacrificed at 1 or 4 weeks following implantation. Histological (multinucleated giant cell count) and immunohistochemical (expression of matrix metalloproteinases MMP-1,-2,-3,-9,-13) markers of inflammation were examined. RESULTS: Multinucleated giant cells were present in all specimens containing suture material but not in the control specimens. No significant differences were found in the number of giant cells between the intact suture groups at either time point. Significantly higher numbers of giant cells were noted in the particles C group compared to the intact suture C group at both time points (p = 0.021 at 1 week, p = 0.003 at 4 weeks). Quantitative analysis of immunohistochemical staining expression at 4 weeks showed that significantly more MMP (-1,-2,-9,-13) was expressed in the particles C group than the intact suture C group (p = 0.024, p = 0.009, p = 0.002, and p = 0.007 for MMP-1, MMP-2, MMP-9, and MMP-13, respectively). No significant difference was seen in the expression of MMP-3 (p = 0.058). CONCLUSIONS: There were no differences observed between the biological reactivity of commonly used intact orthopaedic sutures A, B, and C. However, wear particles of suture C elicited a significantly greater inflammatory response than intact suture alone. This was confirmed by increased numbers of multinucleated giant cells as well as MMP ( -1,-2,-9,-13) expression. Further studies are needed to determine whether this inflammatory response may play a role in the development of post-arthroscopic glenohumeral chondrolysis or interfere with biological healing. These findings have important clinical implications relating to surgical technique and surgical implant design.