The role of probiotics for preventing dysbiosis in periodontal disease: a randomized controlled trial.

Background/aim: Scaling and root planing remain inadequate in periodontitis treatment caused by dysbiotic microbial dental plaque. The aim of this clinical trial is to evaluate the effects of probiotics and kefir consumption in initial periodontal therapy (IPT) on oral microbiota composition and treatment outcomes in patients with periodontitis. Materials and methods: The study was carried out in the Gazi University Department of Periodontology, including a sample size of 36 individuals and utilizing a randomized controlled design. Thirty-six patients with periodontitis were randomly allocated to three groups: one receiving probiotic treatment, another receiving kefir, and a third serving as the control group. Obtaining subgingival microbial samples, we recorded plaque, gingival index, bleeding on probing, periodontal pocket depth, and clinical attachment level (periodontal clinical indices) and then performed IPT. For 14 days, patients took either probiotics, kefir, or no supplements. Data for the first and third months were collected using periodontal clinical indices. DNA sequencing was performed to detect Tannerella forsythia, Porphyromonas gingivalis, and Treponema denticola in subgingival plaque samples collected at baseline and three months. Results: Significant differences were observed regarding periodontal clinical indices among groups in the intragroup comparisons. Moreover, levels of Tannerella forsythia were significantly decreased in all groups. Conclusion: Kefir can be administered in addition to IPT, providing results similar to those observed with probiotics.

Interaction between hypertension and periodontitis.

OBJECTIVE: The possible association between hypertension and periodontitis and the effect of hypertension on periodontal treatment were investigated by evaluating salivary and gingival crevicular fluid (GCF) interleukin (IL)-6 and C reactive protein (CRP) levels. METHODS: Forty-two healthy individuals without any previously diagnosed systemic disease [10 periodontally healthy (control) and 10 periodontitis (CP)] and subjects with hypertension [13 periodontally healthy (HP) and 9 with periodontitis (CP + HP)] participated in the study. GCF and saliva samples were obtained at baseline and 4 weeks after Phase I periodontal treatment. Biochemical parameters were analyzed using ELISA. RESULTS: Before the periodontal treatment, significantly higher GCF IL-6 and CRP levels were detected in CP + HP and CP groups compared to HP and control groups (p < 0.01). Salivary CRP level in CP + HP group was found to be higher than the control group (p < 0.05). Statistically significant gingival and plaque index measurements (p < 0.01) might suggest a possible effect of hypertension on periodontal status. Periodontal treatment significantly improved the clinical indices; however, biochemical parameters did not change after the treatment. CONCLUSION: The association of hypertension with periodontitis through local salivary and GCF inflammatory mediators might be possible in disease process.

Evaluation of periodontal status and cytokine levels in saliva and gingival crevicular fluid of patients with inflammatory bowel diseases.

BACKGROUND: Periodontal diseases and inflammatory bowel diseases (IBD, ulcerative colitis [UC] and Crohn disease [CD]) have been reported to present with increased salivary and gingival crevicular fluid (GCF) concentrations of cytokines. The aim of this study was to evaluate the salivary and GCF levels of TNF-α, IL-1ß, IL-10, and IL-17A and their associations with the periodontal statuses of UC, CD, and non-IBD patients, and to analyze the interrelationships among these cytokines, IBD conditions, and periodontal diseases. METHODS: This cross-sectional study was performed with a total of 131 patients (62 women and 69 men, mean age 42.96±13.02 years). Patients were divided into three groups: UC, CD, and non-IBD. Periodontal status was defined according to the 2017 World Workshop Disease Classification. Salivary and GCF cytokine levels were analyzed using ELISA. RESULTS: UC and CD patients diagnosed as having periodontitis and gingivitis presented with significantly higher levels of TNF-α and lower levels of IL-10 as compared with non-IBD patients (p<0.05). UC patients diagnosed with periodontitis exhibited significantly higher scores of bleeding on probing (p = 0.011) and increased salivary and GCF IL-1ß levels as compared with CD patients (p = 0.005, and 0.012, respectively). Considering the active and remission status of IBD, salivary IL-1ß was found to be correlated with the parameters representing the severity of periodontal diseases in active UC and CD patients. CONCLUSION: In the presence of periodontal diseases, UC and CD patients showed different expression levels of TNF-α, IL-1ß, and IL-10 in oral secretions as compared with non-IBD patients.

Histomorphometric and biomechanical evaluation of the osseointegration around micro- and nano-level boron-nitride coated titanium dental implants.

INTRODUCTION: Titanium dental implants has been coated with different materials such as polymers and biomimetic agents, bone morphogenetic protein, calcium phosphate to enhance surface properties of the titanium implants for osseointegration. The aim of this study was to evaluate the bone tissue healing around Boron Nitride-coated (BN-coated) titanium implants histomorphometrically and biomechanically and also observe the effect of different coating thicknesses on osseointegration. MATERIALS AND METHODS: BN was coated on dental titanium implants with two different coating thicknesses by using RF magnetron sputtering system. Totally fifty-four implants were inserted into the tibias' of 12 New Zealand rabbits bilaterally under general anesthesia. All animals were sacrificed after 4-weeks. Bone-implant contact (BIC) and new bone area/total area ratios (BATA) were calculated. Also, the removal torque (RT) test was performed. RESULTS: The highest new bone area in the medullary cavity was around the nano-BN-coated surface with 15.70%. In micro-BN-coated surface and control group, this ratio was determined as 10.48% and 8.23%, respectively. The BIC ratios in upper-side of implants and cortical-associated BIC ratios in lower-side were found significantly higher in control and micro-BN-coated group than nano-BN-coated group (p < 0.05). Similar BIC values were observed between control and micro-BN-coated groups (p > 0.05). BATA values did not show statistically significant differences between all three groups (p > 0.05). The RT values measured in all groups were found comparable and no statistically significant differences were found (p > 0.05). CONCLUSION: No inflammatory reaction developed around any implant. Relatively more new bone formation around nano-BN-coated titanium implants indicates the promising osseoinductive effect of BN coating. BN-coated implants showed similar biomechanical and histomorphometrical outcomes to that of the conventional titanium implants through a 4-week evaluation period.

How old is old for implant therapy in terms of implant survival and marginal bone levels after 5-11 years?

AIM: To evaluate implant survival and marginal bone levels (MBLevel ) at least 5 years after implant installation in patients ≥65 years old. METHODS: Patient records were screened retrospectively for the following inclusion criteria: (1) ≥65 years of age at the time of implant installation, and (2) ≥5-year radiographic follow-up or registered implant loss. Association between patient- and implant-related data with radiographically assessed data [i.e. implant survival, mean MBLevel (i.e. average of mesial and distal level) and maximum marginal bone loss (i.e. either mesial or distal loss; maximum MBLoss )] were statistically evaluated by mixed effects multi-level regression models. RESULTS: Two-hundred-eighteen implants in 74 patients were included with a mean follow-up of 6.2 years (range: 5 to 10.7 years); four early and six late implant losses have been registered (implant survival rate: 95.4%). Mean MBLevel and maximum MBLoss was 1.24 ± 0.9 mm and 1.48 ± 1.0 mm, respectively. Maximum MBLoss  < 2 mm, 2 to 5 mm and ≥5 mm was found in 70.7, 28.8 and 0.5% of the implants, respectively. For both, mean MBLevel and maximum MBLoss , age presented a slightly protective effect (mean MBLevel : Coef. -0.041, p = .016; maximum MBLoss : Coef. -0.045, p = .014). CONCLUSION: The high implant survival rate (95.4%), low mean MBLevel (1.24 mm) and low frequency of maximum MBLoss  ≥ 5 mm (0.5%) observed herein after 5 to 11 years follow-up suggest that older age should not be considered as a limiting factor for implant treatment.

Levels of Cytokines in Gingival Crevicular Fluid during Rapid Maxillary Expansion and the Subsequent Retention Period.

OBJECTIVE: To monitor the effects of rapid maxillary expansion (RME) on bone metabolic activities during and after 3 months of retention. STUDY DESIGN: Fifteen patients with a mean age of 12.9 ± 0.6 years were treated with a bonded expansion device, activated 2 turns per day. The retention period was 3 months. Clinical periodontal parameters were recorded at baseline and after retention. Gingival crevicular fluid (GCF) samples were collected from maxillary first molars from the compression sides at baseline, then at 1 and 10 days and after retention. Tension side samples were obtained at baseline and after retention. Interleukin-1beta (IL-1ß), transforming growth factor beta1 (TGF-ß1), prostaglandin E2 (PGE2) and nitric oxide (NO) levels were specifically measured. RESULTS: Periodontal parameters increased significantly after retention relative to baseline values. Levels of IL-1ß, TGF-ß1 and PGE2 increased on day 10, and decreased after retention on the compression side. NO levels were elevated on day 10, and remained higher after retention on the compression side. Tension side cytokine levels remained higher relative to baseline values after retention. CONCLUSIONS: The results of this study indicate the importance of ongoing adaptive bone activities after 3 months of retention with RME, which should be considered questionable as an effective retention period.

The Association between Inflammatory Bowel Disease and Periodontal Conditions: Is There a Common Bacterial Etiology?

INTRODUCTION: The gastrointestinal system is strongly associated with the oral mucosa including periodontal tissues. Infl ammatory bowel disease (IBD) has two common forms: Crohn's disease (CD) and ulcerative colitis (UC). Local inflammation in periodontal diseases (PD) has an impact on infl ammatory diseases in various parts of the body. The existence of periodontitis in IBD patients suggests the possibility that the two inflammatory conditions may have common pathogenic pathways. Both diseases are multifactorial conditions in which genetic and environmental factors initiate and maintain the chronic inflammatory response. AIM: The aim of this review was to determine the current state of understanding of the characteristics and mechanisms underlying the association between IBD and periodontal diseases, with emphasis on the role of microorganisms. METHODS: A computer-assisted MEDLINE search was performed to find the relevant articles concerning IBD and periodontal diseases published until September 2016. RESULTS AND CONCLUSION: A number of studies have showed an association between PD and IBD. Both diseases share genetic and environmental etiological factors. The precise role of intestinal bacteria remains vague. The periodontal microbiota that might be involved in the association of these diseases are Fusobacterium nucleatum, Campylobacter rectus and Campylobacter concisus. Fungal and viral microbiota dysbiosis should also be evaluated as common pathogenic pathways in IBD and periodontal disease.

Nitric oxide and arginase levels in peri-implant tissues after delayed loading.

OBJECTIVE: Nitric oxide (NO) is synthesized from the conversion of L-arginine to L-citrulline by NO synthase (NOS). Arginase can compete with NOS for the common substrate L-arginine, and thus inhibit NO production. NO levels and arginase ezyme might affect the bone remodeling cycle around implants. The aim of this studywas to investigate NO and arginase levels in gingival crevicular fluid (GCF), peri-implant sulcular fluid (PISF), and saliva. MATERIALS AND METHODS: Twenty patients with one or more implants (Straumann®; Institute Straumann AG, Basel, Switzerland) restored with fixed crown prostheses were included in the study. Plaque index (PI), gingival index (GI), probing depth (PD), and bleeding on probing (BOP) were recorded from six sites of each tooth and implant at baseline and at months 1, 3, and 6 after loading. The saliva, GCF, and PISF were collected at baseline and at months 1, 3, and 6 after loading. NO level and arginase enzyme were evaluated in GCF, PISF, and saliva. RESULTS: Arginase and NO levels in saliva did not change significantly from baseline to months 1, 3, and 6. However, both PISF NO and arginase levels showed an increased pattern from baseline to month 6. NO levels were significantly higher at months 3 and 6, compared to baseline, while PISF arginase levels increased significantly from baseline to months 3 and 6. CONCLUSION: NO and arginase enzyme measurements in saliva, GCF, and PISF may be beneficial in the determination of current peri-implant tissues. In particular, PISF might provide more information than saliva.

Comparison of Radiofrequency and Electrocautery With Conventional Scalpel Incisions.

PURPOSE: The disadvantages of conventional scalpels, including insufficient control of bleeding, prompted us to search for new alternative methods such as electrosurgery and radiosurgery. In this study, the conventional scalpel was compared with radiosurgery and electrosurgery for wound healing with assessment of lateral heat production, inflammation, and instrument performance. MATERIALS AND METHODS: Incisions were made in the palatal mucosa of 42 Wistar rats using a scalpel, electrocautery instrument, or radiofrequency instrument. Postoperative hemostasis, tissue coagulation, and tissue sticking were measured, and pain evaluation through weight loss was recorded. Gingival biopsy specimens from the surgical area were obtained at the time of surgery and 2, 4, 7, and 14 days postoperatively and were evaluated immunohistochemically for inducible nitric oxide synthase and heat shock protein 70. Kruskal-Wallis, 1-way analysis of variance, and Mann-Whitney U tests were used for statistical evaluation. RESULTS: The rats in the electrosurgery and radiosurgery groups had aggressively greater weight loss when compared with the scalpel group in the first 7 days. Hemostasis was better in the electrocautery group, tissue coagulation was greater in the radiofrequency group (P < .001), and tissue sticking was lesser in the scalpel group (P < .001) compared with the other groups. Inducible nitric oxide synthase expression and heat shock protein 70 expression were similar in all 3 groups. CONCLUSIONS: Electrosurgery performed better regarding hemostasis, whereas a scalpel was superior in terms of tissue sticking and tissue coagulation. Radiosurgery was superior regarding hemostasis when compared with a conventional scalpel, but it was not as successful as electrosurgery.

Does laterally rotated flap design influence the short-term periodontal status of second molars and postoperative discomfort after partially impacted third molar surgery?

PURPOSE: To assess the influence of the surgical removal of partially impacted third molars (3Ms) and compare the effects of a 3-cornered laterally rotated flap (LRF) with primary closure (flap 1) and an envelope flap with secondary closure (flap 2) on the short-term periodontal status of the adjacent second molars (2Ms). We also assessed the postoperative complications after removal of the partially impacted 3M. MATERIALS AND METHODS: A split mouth, randomized clinical study was designed. The study sample included patients with bilateral partially impacted 3Ms. The primary predictor variable was the type of flap design (flaps 1 and 2). The primary outcome variable was periodontal status (gingival recession [GR], probing depth [PD], plaque index [PI], and gingival index) of the 2Ms measured preoperatively and 90 days postoperatively. The secondary outcome variables were postoperative complications, including pain, facial swelling, alveolitis, and local wound infection. The other variables included gender, position of the 3Ms, and surgical difficulty. We performed descriptive, comparative, correlation, and multivariate analyses. RESULTS: The sample included 28 patients aged 18 to 28 years. The GR, PD, and PI values with the flap 2 design were greater than those with the flap 1 design (P < .05). Facial swelling with the flap 1 design was significantly greater than with the flap 2 design on the second postoperative day (P < .05). The pain levels with the flap 1 design were significantly greater than those with the flap 2 design on the first and second postoperative days (P < .05). According to the multivariate regression analyses, flap design was closely related to the periodontal status of the 2Ms and postoperative discomfort. CONCLUSION: The results of the present clinical study have shown that the flap design in partially impacted 3M surgery considerably influences the early periodontal health of the 2Ms and postoperative discomfort. However, although the 3-cornered LRF design might cause more pain and swelling, it could be the method of choice for partially impacted 3M surgery because of the early periodontal healing.

The effect of light-emitting diode photobiomodulation on implant stability and biochemical markers in peri-implant crevicular fluid.

OBJECTIVE: The purpose of this study was to determine the effect of light-emitting diode photomodulation (LED PBM) on implant osseointegration by measuring implant stability changes by resonance frequency analysis (RFA) and measuring interleukin-1ß (IL-1ß), transforming growth factor-ß (TGF-ß), prostaglandin-E2 (PGE2), and nitric oxide (NO) levels in peri-implant crevicular fluid (PICF). BACKGROUND DATA: Light therapy modulates various biological events and allows improved wound healing in ischemic and wounded tissues. METHODS: Fifteen patients (8 control, 7 LED) participated in the study. In the LED group, LED device at a wavelength of 626 nm in the near-infrared (NIR) region (treatment array area: 4.80 cm2; average intensity: 38.5 mW/cm2; total power: 185 mW; total energy: 222 J; average density: 46.2 J/cm2) was applied for 20 min over the surgical area during 3 weeks, three times in a week, starting from the operation day. Implant stability quotient (ISQ) values were recorded at the time of operation, and 2, 4, 8, and 12 weeks postoperatively. PICF samples were collected in postoperative weeks 4 and 12 and IL-1ß, TGF-ß, PGE2, and NO levels were evaluated. Clinical indices were recorded around implants in postoperative weeks 4 and 12. RESULTS: In the control group, significant reduction of ISQ values from week 2 to week 12 were demonstrated. In the LED group, baseline ISQ values were maintained during the study and no significant changes were observed. Changes in biochemical parameters were found to be similar between groups over time. However, in the LED group, a negative correlation was found between PGE2 and ISQ values. CONCLUSIONS: LED application to surgical area has a positive effect on the osseointegration process, and implant stability can be maintained.

Receptor activator of NF-kappaB ligand (RANKL) and CD 31 expressions in chronic periodontitis patients before and after surgery.

AIM OF THE STUDY: The present study investigated the hypothesis that upregulation of receptor activator of NF-kappaB ligand (RANKL) expression may be associated with upregulation of endothelial cell activitiy, which is common for periods of periodontal bone loss in chronic periodontitis. MATERIAL AND METHODS: RANKL expression of activated cells in soft tissue biopsies with CD 31 activity and the presence of RANKL and osteoprotegerin (OPG) in gingival crevicular fluid (GCF) were assessed in chronic periodontitis patients. Biopsies from 17 patients and 10 healthy subjects were immunohistochemically analyzed. Clinical measurements [plaque index (PI), the gingival index (GI), probing pocket depth (PPD), clinical attachment level (CAL) and gingival bleeding index (GBI)] and GCF samples were obtained before and after periodontal therapy. RESULTS: CD31 staining did not support the assumption that endothelium-like cells were predominantly associated with RANKL expression. CONCLUSIONS: RANKL-positive cells were widely distributed in periodontitis patients giving only partial support to the hypothesis that RANKL expression is restricted to T- and B-cell activation.

Periodontal nitric oxide pathway alteration due to precompetition anxiety in handball players.

BACKGROUND: Psychologic and physical stress is known to be related with periodontal disorders. The objective of this study is to investigate salivary and gingival crevicular fluid (GCF) nitric oxide (NO) metabolism and its association with the periodontal reaction to precompetition anxiety in competitive athletes. METHODS: A total of 18 elite male handball players participated in this study. The anxiety level of participants was determined by using a competitive state anxiety inventory-2 (CSAI-2). Periodontal clinical measurements, saliva, and GCF samples were obtained before the application of the CSAI-2 during the half-season break and just before the league championship match. NO-level, arginase, and NO synthase (NOS) activities were analyzed in saliva samples; NO and basic fibroblast growth factor (FGF-b) levels were analyzed in GCF samples. RESULTS: The CSAI-2 was significantly different between the two evaluation time points. GCF NO and FGF-b levels increased before the championship match, whereas saliva levels did not change. The plaque index and gingival index (GI) increased at the evaluation just before the championship match. The difference in the GI was statistically significant. CONCLUSION: The competitive stress of athletes may lead to a gingival/periodontal disturbance accompanied by an altered NO metabolism in saliva and GCF.

Arginine-nitric oxide-polyamine metabolism in periodontal disease.

BACKGROUND: Arginine is converted to nitric oxide (NO) via NO synthase and to ornithine via arginase. Ornithine decarboxylase (ODC) catalyzes the conversion of ornithine to polyamines. Arginase can inhibit NO production, and NO can inhibit ODC activity as part of an early inflammatory response. This study examines the arginine-NO-polyamine pathway alteration in saliva and gingival biopsy samples of patients with gingivitis or periodontitis and healthy controls and evaluates the response to periodontal treatment. METHODS: This study includes nine gingivitis patients, 15 chronic periodontitis patients, and 11 healthy age-matched controls. Periodontal clinical measurements, gingival biopsies, and saliva samples were obtained before treatment (BT) and 1 month after periodontal treatment (AT). Arginase and ODC activities and NO levels were determined spectrophotometrically. RESULTS: The BT salivary and gingival NO levels were found to be highest in the gingivitis group, followed by the healthy and the periodontitis groups, respectively. Salivary NO levels significantly increased in the periodontitis group and decreased in the gingivitis group AT (P <0.05). Gingival NO levels decreased significantly in the periodontitis and the gingivitis groups AT (P <0.05). Arginase levels were detected highest in the gingivitis group and lowest in the periodontitis group, both in saliva and gingiva. Only gingival arginase levels significantly increased AT (P <0.05). ODC activity was highest in saliva, and lowest in the gingiva of the periodontitis patients BT. It was found to be significantly higher in the periodontitis group AT (P <0.05). CONCLUSIONS: In this study, regarding arginine-NO-polyamine metabolism, gingival tissue seems to be more informative about periodontal pathogenesis than saliva. At early phase of periodontal inflammation, NO arginase and ODC levels were measured as higher than at an established lesion of periodontitis.

Impact of chlorhexidine mouth rinse use on postextraction infection via nitric oxide pathway.

OBJECTIVE AND DESIGN: Nitric oxide (NO) has been linked to inflammatory reactions, tissue destruction, host defense, and wound healing in oral diseases. It is known that arginase enzyme controls the synthesis of NO through arginine depletion. This study evaluated the arginase-NO pathway alteration in response to tissue injury after dental extraction surgery and the effect of postoperative use of 0.2% chlorhexidine gluconate rinse (CHX). MATERIALS AND METHODS: This study included 28 individuals who had impacted mandibular third molars. They were randomly divided into two groups. Group A was comprised of 13 individuals who used postoperative CHX (0.2%) rinse, while group B included 15 individuals who did not use postoperative CHX rinse. For each patient, periodontal inflammatory status was evaluated. Salivary and gingival tissue samples were obtained before and 1 h and 1 week after the surgery to determine the NO level and arginase activity using spectrophotometric methods. RESULTS: NO level of tissue samples displayed an insignificant decrease in both groups postoperatively. However, arginase activity of tissue samples was significantly higher in group B compared to group A 1 week after surgery (p

The evaluation of cystatin C, IL-1beta, and TNF-alpha levels in total saliva and gingival crevicular fluid from 11- to 16-year-old children.

BACKGROUND: The aim of this study was to evaluate the levels of cystatin C, interleukin-1beta (IL-1beta), and tumor necrosis factor-alpha (TNF-alpha) in the total saliva and gingival crevicular fluid (GCF) of periodontally healthy children (PHC) and children with gingivitis (CG) who were between 11 and 16 years old. METHODS: The study was carried out with 10 PHC and 25 CG. Unstimulated total saliva and GCF samples were obtained. Clinical parameters, including probing depth (PD), clinical attachment loss (CAL), plaque index (PI), gingival index (GI), and gingival bleeding index (GBI), were assessed. GCF samples were collected from four maxillary upper incisors. After sampling, biochemical analyses were performed using latex particle-enhanced turbidimetric immunoassay for cystatin C and enzyme-linked immunosorbent assay for IL-1beta and TNF-alpha. The multivariate analysis of variance test was used for statistical evaluation. RESULTS: In total saliva, cystatin C and TNF-alpha levels were higher in PHC, and IL-1beta levels were higher in CG, but the differences were not statistically significant. In GCF, cystatin C levels were higher in PHC (P >0.05), whereas TNF-alpha and IL-1beta levels were higher in CG (P >0.05). In the CG group, there were positive correlations between the GCF cystatin C level and the PI of the sampled site (r = 0.488; P <0.05); also, GCF IL-1beta (r = 0.603; P <0.05) and TNF-alpha (r = 0.456; P <0.05) levels were positively correlated with PD and CAL. For the whole mouth and the sampled sites, PI, GI, GBI, PD, and CAL values were higher in CG (P <0.05), but no significant differences were detected between GCF volumes of the two groups. CONCLUSIONS: To the best of our knowledge, this study represents the first evaluation of cystatin C in the gingival disease mechanism in children. Our results showed that total saliva and GCF cystatin C levels were higher in PHC (P >0.05), but there was no correlation between cystatin C levels and IL-1beta or TNF-alpha levels in total saliva or GCF.

Cone-beam computed tomography in assessment of periodontal ligament space: in vitro study on artificial tooth model.

The aim of this in vitro study was to compare cone-beam computed tomography (CBCT) to conventional radiography (RG) in the assessment of the periodontal ligament space. A phantom with a variable "artificial" periodontal ligament space (0, 100, 200, 300, and 400 microm) was used as a model. The examinations were performed simultaneously with RG and NewTom 9000 digital volume tomograph. Assorted after increasing widths, 15 RGs and 15 CBCT images were presented for judgment to 20 dentists (DD), 20 dental assistants, and 20 dental students. Several weeks later, the same images were randomly mixed and presented to the same 20 DD again. The trial shows that RG gaps wider than 200 microm could be correctly identified by all participants with an accuracy of nearly 100%. A significant difference was observed between the modalities (p<0.05 and p<0.001) where conventional RGs performed better than CBCT for assessment of periodontal ligament space. Interobserver variation in relation to each technique was evaluated and no significant difference was found (p>0.05). In subjective evaluations of image quality with CBCT, the results were basically inferior for images of artificial periodontal ligament space, regardless of the experience of the observers.

The Evaluation of Cystatin C, IL-1ß, and TNF-α Levels in Total Saliva and Gingival Crevicular Fluid From 11- to 16-Year-Old Children.

BACKGROUND: The aim of this study was to evaluate the levels of cystatin C, interleukin-1ß (IL-1ß), and tumor necrosis factor-alpha (TNF-α) in the total saliva and gingival crevicular fluid (GCF) of periodontally healthy children (PHC) and children with gingivitis (CG) who were between 11 and 16 years old. METHODS: The study was carried out with 10 PHC and 25 CG. Unstimulated total saliva and GCF samples were obtained. Clinical parameters, including probing depth (PD), clinical attachment loss (CAL), plaque index (PI), gingival index (GI), and gingival bleeding index (GBI), were assessed. GCF samples were collected from four maxillary upper incisors. After sampling, biochemical analyses were performed using latex particle-enhanced turbidimetric immunoassay for cystatin C and enzyme-linked immunosorbent assay for IL-1ß and TNF-α. The multivariate analysis of variance test was used for statistical evaluation. RESULTS: In total saliva, cystatin C and TNF-α levels were higher in PHC, and IL-1ß levels were higher in CG, but the differences were not statistically significant. In GCF, cystatin C levels were higher in PHC (P >0.05), whereas TNF-α and IL-1ß levels were higher in CG (P >0.05). In the CG group, there were positive correlations between the GCF cystatin C level and the PI of the sampled site (r = 0.488; P <0.05); also, GCF IL-1ß (r = 0.603; P <0.05) and TNF-α (r = 0.456; P <0.05) levels were positively correlated with PD and CAL. For the whole mouth and the sampled sites, PI, GI, GBI, PD, and CAL values were higher in CG (P <0.05), but no significant differences were detected between GCF volumes of the two groups. CONCLUSIONS: To the best of our knowledge, this study represents the first evaluation of cystatin C in the gingival disease mechanism in children. Our results showed that total saliva and GCF cystatin C levels were higher in PHC (P >0.05), but there was no correlation between cystatin C levels and IL-1ß or TNF-α levels in total saliva or GCF.

Comparison of different methods to detect Helicobacter pylori in the dental plaque of dyspeptic patients.

The aim of this study was to compare different methods of detection of Helicobacter pylori (H. pylori) in the dental plaque of dyspeptic patients. After recording the clinical indices, culture and polymerase chain reaction (PCR) methods were performed on plaque samples, while rapid urease test in addition to these tests was carried on gastric samples from 67 dyspeptic patients who attended for an upper gastrointestinal endoscopy. Forty-seven of 67 patients were H. pylori-positive in gastric biopsy material whereas the microbial dental plaque from 19 patients demonstrated H. pylori positivity detected by PCR. Among the patients, 25.4% harbored H. pylori both in the stomach and in microbial dental plaque. No significant correlations were found among the presence of H. pylori in the stomach, in plaque, and clinical variables (P > 0.05). Although oral hygiene was observed optimal and the mean of pocket depth was not found to be higher, the prevalence of H. pylori was observed to be higher in dental plaque. According to our results, PCR technique gave the highest detection rate both in gastric biopsy and in dental plaque compared to the other methods used.

A multifaceted molecule, nitric oxide in oral and periodontal diseases.

Nitric oxide (NO) is a molecule with multiple effects on different tissues. NO takes important roles in vasodilatation, bacterial challenge and cytokine stimulation, regulation of mineralized tissue function, neurotransmission, and platelet aggregation, etc. However, under pathological conditions, NO has damaging effects. NO is synthesized by NO synthases (NOS) and inducible isoform of NOS (iNOS) is closely related to the pathophysiological characteristics of inflammatory diseases such as periodontal diseases. The expression of iNOS has been investigated in salivary gland-related diseases, temporomandibular joint disorders and oral cancer as well. The beneficial and damaging effects of NO in diseases related with periodontal, dental and maxillofacial area are discussed in this review. The biological pathways involved with NO and NO inhibitors may be good drug targets to have a role in the future management of patients with diseases in orofacial region.