Background: Lipocalin-2 (LCN-2) is an osteokine that suppresses appetite, stimulates insulin secretion, regulates bone remodeling, and is induced by proinflammatory cytokines. The aim of this work was to investigate the participation of LCN-2 in periodontitis associated with type 2 diabetes (T2D) by evaluating alveolar bone loss, glycemic control, inflammation, and femur fragility.
Methods: A murine model of periodontitis with T2D and elevated LCN-2 concentration was used. Functional LCN-2 inhibition was achieved using an anti-LCN-2 polyclonal antibody, and isotype immunoglobulin G was used as a control. The alveolar bone and femur were evaluated by micro-CT. Glucose metabolism was determined. Tumor necrosis factor (TNF-α) and receptor activator of nuclear factor kappa-B ligand (RANKL) levels in alveolar bone lysates were quantified using ELISA, and serum cytokines were quantified using flow cytometry. A three-point bending test was performed in the femur, and RANKL levels were measured in femur lysates using ELISA.
Results: Functional inhibition of LCN-2 in T2D-periodontitis mice decreased alveolar bone loss in buccal and palatal surfaces and preserved the microarchitecture of the remaining bone, decreased TNF-α and RANKL in alveolar bone, reduced hyperglycemia, glucose intolerance, and insulin resistance, and increased insulin production through improving the functionality of pancreatic β cells. Furthermore, this inhibition increased serum free-glycerol levels, decreased serum interleukin (IL)-6, increased serum IL-4, and reduced femur fragility and RANKL expression in the femur.
Conclusions: LCN-2 participates in periodontitis associated with T2D. Inhibiting its function in mice with T2D and periodontitis improves pancreatic β-cell function, and glucose metabolism and decreases inflammatory cytokines and bone-RANKL levels, which results in the preservation of femoral and alveolar bone microarchitecture.
Plain language summary: In this study, we explored the role of a bone protein known as lipocalin-2 (LCN-2) in the connection between periodontitis and type 2 diabetes (T2D). Periodontitis is a destructive gum and alveolar bone disease. LCN-2 levels are increased in both T2D and periodontitis. Using a mouse model of T2D with periodontitis, we examined how blocking LCN-2 function affected various aspects of these two diseases. We found that this inhibition led to significant improvements. First, it reduced alveolar bone loss and preserved bone structure by decreasing local inflammation and bone resorption. Second, it improved glucose and lipid metabolism, leading to better blood-sugar control and decreased insulin resistance. Blocking the functions of LCN-2 also decreased systemic inflammation throughout the body and strengthened bone integrity. Overall, our results suggest that LCN-2 plays a crucial role in the periodontitis associated
Background: This study aimed to analyze the influence of concave and cylindrical abutments on peri-implant soft tissue. Dimensions, collagen fiber orientation, and immunohistochemical data were assessed.
Methods: A multicenter, split-mouth, double-blind randomized clinical trial was conducted. Two groups were analyzed: cylindrical abutments and concave abutments. After a 12-week healing period, peri-implant soft tissue samples were collected, processed, and evaluated for dimensions, collagen fiber orientation, and immunohistochemical data. Inflammatory infiltration and vascularization were assessed, and the abutment surfaces were analyzed using scanning electron microscopy. The statistical analysis was performed using the SPSS version 20.0 statistical package.
Results: A total of 74 samples in 37 patients were evaluated. Histological evaluation of peri-implant soft tissue dimensions revealed significant differences between concave and cylindrical abutments. Concave abutments exhibited greater total height (concave: 3.57 ± 0.28 - cylindrical: 2.95 ± 0.27) and barrier epithelium extension (concave: 2.46 ± 0.17 - cylindrical: 1.89 ± 0.21) (p < 0.05), while the supracrestal connective tissue extension (concave: 1.11 ± 0.17 - cylindrical: 1.03 ± 0.16) was slightly greater (p > 0.05). Collagen fiber orientation favored concave abutments (23.76 ± 5.86), with significantly more transverse/perpendicular fibers than for cylindrical abutments (15.68 ± 4.57). The immunohistochemical analysis evidenced greater inflammatory and vascular intensity in the lower portion for both abutments, though concave abutments showed lower overall intensity (concave: 1.05 ± 0.78 - cylindrical: 1.97 ± 0.68) (p < 0.05). The abutment surface analysis demonstrated a higher percentage of tissue remnants on concave abutments (42.47 ± 1.32; 45.12 ± 3.03) (p < 0.05).
Conclusions: Within the limitations of this study, concave abutments presented significantly greater peri-implant tissue height, linked to an extended barrier epithelium, versus cylindrical abutments in thick tissue phenotype. This enhanced soft tissue sealing, favoring a greater percentage of transversely oriented collagen fibers. The concave design reduced chronic inflammatory exudation with T and B cells, thus minimizing the risk of chronic inflammation.
Plain language summary: This study looked at how 2 different shapes of dental implant abutments (the parts that connect the implant to the crown), specifically concave and cylindrical, affect the soft tissue around the implants. We wanted to see how these shapes influenced the tissue's size, structure, and health. We conducted a clinical trial with 37 patients, comparing the 2 types of abutments in the same mouth over 12 weeks. Our findings showed that the concave abutments led to a taller and more extensive layer of protective tissue around the implant comp
Background: To assess how the diagnostic reproducibility of the 2018 Classification of Gingival Recession Defects (GRD) could be applied when comparing in-person chairside measurements with photographic measurements.
Methods: Thirty-four GRD were photographed and evaluated by 4 masked operators. For each case, the operators measured twice recession type (RT), recession depth (RD), keratinized tissue width (KTW), gingival thickness (GT), detectability of the cemento-enamel junction (CEJ), and presence of root steps (RSs), chairside, and on photographs. Intraclass correlation coefficient (ICC) with 95% confidence intervals (CI) was calculated for RD and KTW; Kappa with 95% CI was used for GT, CEJ, and RS; quadratic weighted Kappa with 95% CI was used for RT.
Results: RD, KTW, and RT showed excellent overall intra-operator agreement (> 0.93), and from good to excellent overall inter-operator agreement (> 0.80), for both clinical and photographic measurements. Agreements were lower for GT, CEJ, and RS. Overall clinical and photographic agreements were within 0.1 difference for every variable, except for inter-operator agreement for RS which was 0.72 for clinical measurements and 0.45 for photographic measurements. The lowest overall agreement between clinical versus photographic measurements existed for CEJ (0.28) and RS (0.35).
Conclusions: Variables composing the 2018 Classification of GRD are reproducible, both clinically and on photographs, with comparable agreements. The overall agreement was higher for KTW, RD, and RT, and lower for GT, CEJ, and RS, for both clinical and photographic measurements. The comparison between chairside and photographic evaluations indicated fair to excellent agreement for most variables, with CEJ and RS showing fair agreement.
Plain language summary: As digital diagnostics evolve to facilitate clinical diagnostic measurement, we aimed to assess the effectiveness of intraoral photography for diagnosing gingival recession defects (GRD) according to the 2018 Classification of GRD, compared to traditional clinical examination. Standardized photographs of thirty-four GRD cases were captured. Four masked operators evaluated the same gingival recessions twice in a clinical setting and twice using photographs. Measurement repeatability within and between operators was calculated for both clinical and photographic settings, and the two settings were compared. Continuous measurements such as recession depth and keratinized tissue width, as well as the evaluation of interproximal attachment height (recession type), showed excellent agreement both clinically and photographically. Agreement was lower for gingival thickness and the detectability of tooth anatomical landmarks, such as the cemento-enamel junction and the presence of root steps. Overall, the agreement between chairside and photographic evaluations was gener
Background: This study investigated the effect of a 4-week free-sugar avoidance on periodontal parameters during periodontal therapy.
Methods: Twenty-one patients with untreated periodontitis and daily free-sugar intake were allocated to a sugar avoidance group (SAG) and a control group (CG). The SAG received a 45-min dietary consultation and was instructed to avoid free sugars during the following 4 weeks after subgingival instrumentation, while the CG continued with their regular diet. Bleeding on probing (BOP), plaque control record, body weight (BW), visceral fat (FATv), and a food frequency questionnaire (FFQ) were collected at baseline (T1), 4 weeks (T2), and 8 weeks (T3) after subgingival instrumentation.
Results: The main outcome parameter BOP was significantly reduced at T2 by 40.3% ± 15.54 in the SAG and 34% ± 12.47 in the CG (intra-p value both <0.001, inter-p value 0.361). A linear regression analysis of changes at patient level adjusted for age and FATv revealed a significant group difference for BOP (regression coefficient = -6.8; p = 0.019). Significant reductions were observed in BW, FATv and mean daily intake of free sugars (-14.4 g/day), and a significant increase of vitamin C derived from fruits (75.89 mg/day) at T2 in the SAG only.
Conclusion: This study may indicate additional beneficial effects of a sugar avoidance on periodontal and metabolic parameters, and nutritional intake during periodontal therapy. German Clinical Trials Register (DRKS00026699).
Plain language summary: The current widespread free-sugar consumption is linked to an increasing incidence of chronic non-communicable diseases. Data indicate a relationship between sugar intake and a higher prevalence of periodontitis and increased gingival inflammation. This study showed that free-sugar avoidance after periodontal therapy had additional beneficial effects on periodontal and metabolic parameters in 10 test and 11 control patients. After 4 weeks of avoiding free sugars like sweets, processed white flour, juice, and so forth, periodontal bleeding was significantly reduced in both groups (-40.3% test group, -34% control group). Further regression analysis revealed a significant difference between groups favoring the intervention. Additionally, body weight and visceral fat were significantly reduced in the intervention group, only. To avoid sugar, patients were allowed to replace it with whole fruit, which led to increased levels of micronutrients such as vitamin C. Therefore, free-sugar avoidance may be of therapeutic benefit in addition to periodontal therapy. Further research is needed to investigate this effect in larger cohorts.
Background: To compare the efficacy of combined treatment of Er:YAG laser (ERL) and low-level laser therapy (LLLT) with single laser applications, and scaling and root planing (SRP) for non-surgical periodontal treatment.
Methods: In a randomized controlled trial, 25 non-smoking Stage II or Stage III periodontitis patients were recruited. The four intraoral quadrants were randomly assigned to four different treatments: (1) combined application with ERL plus SRP plus LLLT; (2) ERL plus SRP; (3) SRP plus LLLT; and (4) SRP. We assessed periodontal indexes, including probing depth (PD), clinical attachment level (CAL), bleeding index (BI), and plaque index (PLI), along with three cytokines (IL-1β, TNF-α, IL-10) from gingival crevicular fluid and red complex pathogens from subgingival dental plaque at baseline, 3 months, and 6 months.
Results: For initial moderate pockets (4 mm ≤ PD ≤ 6 mm), quadrants treated with ERL+SRP+LLLT, ERL+SRP, and SRP+LLLT exhibited greater PD improvement compared to the control (SRP) quadrants at the 3-month follow-up (1.25 ± 1.06, 1.23 ± 1.12, 1.00 ± 1.21 vs. 0.98 ± 1.21 mm) and the 6-month follow-up (1.35 ± 1.06, 1.23 ± 1.17, 1.35 ± 0.98 vs. 0.98 ± 1.23 mm) (p = 0.002). Quadrants treated with ERL+SRP+LLLT and SRP+LLLT showed more CAL gain means than the control quadrants at the 3-month follow-up (0.96 ± 1.42, 0.61 ± 1.39 vs. 0.55 ± 1.57 mm) and the 6-month follow-up (0.84 ± 1.54, 0.89 ± 1.49 vs. 0.48 ± 1.68 mm) (p = 0.008). For initial deep pockets (PD ≥ 7 mm), the ERL+SRP+LLLT quadrants had more PD improvement and CAL gain compared to the control quadrants at follow-up. There were no significant differences in BI, PLI, inflammatory cytokines, and periodontal pathogens among the four groups.
Conclusion: The combined application of ERL and LLLT demonstrated potential efficacy in reducing PD, particularly for deep pockets.
Plain language summary: To compare the therapy effect of combined use of Er:YAG laser (ERL) and low level laser therapy (LLLT) with single laser applications, and traditional periodontal treatment (SRP). A total of 25 non smoking patients with periodontitis were involved, and their mouths were divided into four sections, each receiving a different treatment: ERL+SRP+LLLT, ERL+SRP, SRP+LLLT, and SRP. Clinical indexes and laboratory indicators were assessed at baseline, 3 months, and 6 months. After six months, for initial moderate pockets, combined laser group and single laser group showed better improvements than traditional group in reducing the depth of periodontal pockets and increasing attachment levels. But for initial deep pockets, only combined laser group showed better improvement than traditional group. There were no significant differences in bleeding, plaque, inflammation, or harmful bacterial levels among the groups. These findings suggest that the integration of Er:YAG laser and low
Background: It is unclear whether an intact buccal bony plate is a prerequisite for immediate implant placement in postextraction sockets. The aim of this 10-year randomized controlled trial was to compare peri-implant soft and hard tissue parameters, esthetic ratings of, and patient-reported satisfaction with immediate implant placement in postextraction sockets with buccal bony defects ≥5 mm in the esthetic zone versus delayed implant placement after alveolar ridge preservation.
Methods: Patients presenting a failing tooth in the esthetic region and a buccal bony defect ≥5 mm after an extraction were randomly assigned to immediate (Immediate Group, n = 20) or delayed (Delayed Group, n = 20) implant placement. The second-stage surgery and provisional restoration placement occurred 3 months after implant placement in both groups, followed by definitive restorations 3 months thereafter. During a 10-year follow-up period, marginal bone levels (primary outcome), buccal bone thickness, soft tissue parameters, esthetics, and patient-reported satisfaction were recorded.
Results: The mean marginal bone level change was -0.71 ± 0.59 mm and -0.36 ± 0.39 mm in the Immediate Group and the Delayed Group after 10 years (p = 0.063), respectively. The secondary outcomes were not significantly different between both groups.
Conclusions: Marginal bone level changes, buccal bone thickness, clinical outcomes, esthetics, and patients' satisfaction following immediate implant placement, in combination with bone augmentation in postextraction sockets with buccal bony defects ≥5 mm, were not statistically different to those following delayed implant placement after ridge preservation in the esthetic zone.
Plain language summary: Immediate implant placement in case of a failing tooth is a favorable treatment option for patients because it considerably shortens treatment time and the number of surgical treatments. The question is if an intact buccal bone wall is necessary for immediate implant placement. A 10-year study was performed in which 20 patients with a failing tooth in the frontal region of the upper jaw were treated with immediate implant placement and were compared with 20 patients in whom a more conventional treatment strategy was followed in which the failing tooth was first removed and the bone gap restored and the implant placed in a second step. After a 10-year follow-up period, it appeared that the bone around the implant was very stable, gums were healthy, and patients were very satisfied with the result. There was no difference between the two treatment procedures. Such results mean that professionals can discuss the procedure with the patient and apply the individual's preference.
Background: This study investigated the agreement among dentists in classifying gingival phenotype (GP) through periodontal probe visibility (PPV) assessment with various probe types and the visual method. Additionally, the relationship between GP classifications and gingival thickness (GT) was evaluated.
Methods: Photographs were taken with standard periodontal probe (SPP), color-coded periodontal probe (CCPP) tips in white, green, and blue, as well as metal phenotype probe (MPP) tips in gray and black. Evaluators (periodontist, periodontics resident, endodontics resident, dental student) assessed the photographs and classified the GPs. GT was measured by trans gingival probing.
Results: Visual method showed poor to fair agreement to classify GP. The lowest agreement regarding PPV was noted with white-tipped CCPP. The highest agreement in singular PPV was observed with CCPP blue (κ = 0.932), followed by CCPP green (κ = 0.791), MPP black (κ = 0.783), SPP (κ = 0.730), and MPP gray (κ = 0.690). Combined PPV data revealed fair to moderate agreement with CCPP and moderate to substantial agreement with MPP in GP classification. The corresponding GT to different GP classifications based on combined PPV were comparable. The agreement between SPP and CCPP in classifying non-thin phenotypes was 89.8%, while the agreement between SPP and MPP was 75.4%. Based on PPV, no significant GT cutoff value was found to distinguish between thin and non-thin phenotypes.
Conclusion: Determining a precise GT that guarantees the visibility of a given probe can be difficult when evaluating GP. Regardless of the type of probe, the PPV method has a high potential for misclassifying GP, despite having an acceptable agreement.
Plain language summary: Gingival phenotype (GP) is constituted by thickness of the gums and width of keratinized tissue around teeth. Direct visual evaluation or evaluating a periodontal probe's visibility beneath gums are established techniques to classify gingival phenotype. This study investigated how dentists classify GP using visual assessments and different types of periodontal probes, while also exploring the relationship between GP classifications and gingival thickness. Results showed varied agreement among dentists in classifying GP, with lower agreement observed when using certain types of probes, notably the white-tipped phenotype probe. The highest agreement was found with the blue phenotype probe. Data from periodontal probe visibility assessments indicated fair to moderate agreement with certain probes, suggesting some inconsistency in classification methods. Interestingly, GP classification with visual assessments or probes did not correlate with gingival thickness, which may highlight the importance of considering both factors in clinical practice. These findings underline the need for attention when relying solely on visual a