Correlations between the Peptide Hormone Ghrelin and Proinflammatory Cytokines in Experimental Periodontitis Models of Female Rats at Different Stages of the Life Cycle.

OBJECTIVE: The aim of this study was to examine the correlations between the levels of ghrelin and inflammatory and bone metabolism markers in rats with periodontitis. DESIGN: Thirty female Wistar rats (6 trial rats and 4 control rats in each group) were divided into pubertal, adult and postmenopausal groups. Periodontitis was induced by ligatures. On the 21 st day, blood was collected and all rats were then sacrificed. The levels of osteocalcin, osteoprotegerin, alkaline phosphatase, tumour necrosis factor alpha (TNF-α), interleukin 1 beta (IL-1ß), acylated ghrelin, total ghrelin and soluble receptor activator of nuclear factor-kB ligands in the blood samples were measured using enzyme-linked immunosorbent assays. The jaws were decalcified in a Tris-EDTA solution and embedded in paraffin and 4-5 µm sections were cut for IL-ß, TNF -α and ghrelin staining. RESULTS: Significantly higher serum alkaline phosphatase levels were detected in the trial rats in the pubertal group than in the control rats (p = 0.033). In the postmenopausal group, ghrelin levels positively correlated with interleukin 1 beta levels (r = 0.708, p < 0.05). Among all trial rats, the postmenopausal group exhibited significantly higher levels of acylated ghrelin than the other groups (p = 0.001). Significantly higher osteoprotegerin levels were observed in the control rats than in the trial rats in the postmenopausal group (p = 0.012). Inflammation scores were significantly higher in adult trial rats than in controls (p = 0.024); significantly higher TNF-α levels were detected in postmenopausal experimental rats than in the adult experimental group (p = 0.025). CONCLUSIONS: We concluded that total ghrelin levels in serum only correlated with IL-ß levels in postmenopausal rats.

Qualitative and Quantitative Assessment of Alveolar Bone Destruction in Adult Rats Using CBCT.

Cone-beam computed tomography (CBCT) has strong potential to be utilized in various aspects of veterinary dentistry. Using ex vivo rat maxillary bone and teeth, the purpose of this study was to compare gray value, surface area, and volumetric measurements of teeth with and without experimental periodontitis by CBCT. Periodontitis was induced in 36 molar teeth, while 36 teeth with a healthy periodontium served as control. Images of each specimen along with teeth were obtained using CBCT. The following measurements for each tooth with periodontitis (n = 36) were recorded: gray value measurement, width, height, depth, surface area, and volume of the alveolar bone loss. For the control group (n = 36), gray value measurement, surface area, and volume of the alveolar bone were recorded. All measurements were repeated after 3 weeks. As the gold standard, the rat maxillas were decalcified and paraffin-embedded for further immunocytochemical study. One-way analysis of variance (ANOVA) was used. Significance level was set at P < .05. Correlation values for gray value, width, height, depth, surface area, and volume measurements were 0.983, 0.966, 0.962, 0.880, 0.998, and 0.999, respectively, for the first and second measurements. One way ANOVA showed statistically significant differences between teeth with and without alveolar bone destruction conducted for gray value, surface area, and volume measurements (P = .000). Mean gray value, surface area, and volume measurements decreased 56.46%, 81.89%, and 78.56%, respectively, for teeth with alveolar bone destruction in comparison to healthy teeth. Cone-beam computed tomography provided useful qualitative and quantitative information regarding induced periodontitis in the rat maxilla.

Vitamin D receptor gene polymorphisms (Apa1 and Taq1) in temporomandibular joint internal derangement/osteoarthritis in a group of Turkish patients.

Genetic variations might play a role in susceptibility to temporomandibular joint internal derangement (TMJ-ID) and osteoarthritis of the joint (TMJOA). Vitamin D receptor (VDR) polymorphisms have been shown to be associated with disc degeneration-linked pathologies, particularly osteoarthritis (OA). The aim of this study was to evaluate whether VDR polymorphisms present susceptibility to TMJ-ID/TMJOA. The study included 49 unrelated TMJ-ID patients with OA (31.7 ± 7.9) that were grouped and evaluated as having anterior disk displacement with reduction (ADDwR, n = 24) (31.58 ± 8.25) and without reduction (ADDwoR, n = 25) (31.8 ± 7.53) and 70 healthy controls (28.22 ± 5.9). DNA was extracted from blood samples using the standard proteinase K/phenol-chloroform method. Apa1 and Taq1 polymorphisms were investigated using a polymerase chain reaction-based restriction fragment length polymorphism assay. When TMJ-ID patients, ADDwR cases and ADDwoR cases versus healthy controls were compared, Apa1 Aa genotype compared to AA genotype had odds ratios of 1.65, 1.79 and 1.64 respectively (p > 0.05). In TMJ-ID women versus healthy women Aa genotype had 2.06 fold (p = 0.15) odds compared to AA genotype. Taq1 results showed that in TMJ-ID patients and ADDwoR cases the Tt genotype had odds ratios of 0.63 and 0.44 fold (p > 0.05) respectively. In TMJ-ID women the Tt and tt genotypes had odds ratios of 0.53 and 0.73 (p > 0.05). Combined VDR genotypes revealed that AATT had a 3.3 fold (p = 1.21) odds ratio while AATt had a 2.0 fold odds ratio (p = 0.29) (OR 0.59, 95% CI 0.23-1.49, p = 0.26) compared to AaTt. Although our results do not confirm susceptibility of VDR polymorphisms to TMJ-ID/TMJOA ,this relation needs to be further evaluated in a large cohort study.

Association of Matrilin-3 Gene Polymorphism with Temporomandibular Joint Internal Derangement.

AIMS: Temporomandibular joint internal derangement (TMJ ID) is a multifactorial complex disease characterised by articular disc degeneration. Matrilin-3 is a cartilage and bone-specific adaptor protein, and amino-acid substitutions in the protein are associated with skeletal diseases and joint disorders. We aimed to detect the variants of Matrilin-3 gene (MATN3) in a TMJ ID case-control group and to investigate the risk association of the detected variants with TMJ ID. MATERIALS AND METHODS: A case control study was conducted consisting of 57 unrelated TMJ ID patients (32.7 ± 8.2) and 96 unrelated healthy controls (26.63 ± 3.05) without TMJ ID to look for associations with variants of the MATN3 gene. DNA from individual subjects was extracted and each of the eight exons was amplified by polymerase chain reaction using and analyzed by single-strand conformational polymorphism (SSCP) analysis. SSCP variants were subjected to DNA sequence analysis, which yielded band pattern variations in exon 2 of the gene. We further analyzed exon 2 by DNA sequencing to determine the sequence of these variants. RESULTS: We identified SSCP band patterns variants in exon 2 of the MATN3 gene which upon sequencing revealed a single C to T transition mutation (rs28598872) c.447 C>T (g.11608 C>T). This polymorphism is predicted to result in a synonymous mutation (pAla149 = ). The TT and CT genotypes were more prevalent than the CC genotype in TMJ ID patients compared to the control group with a risk factor of 2.12 (confidence intervals [CI] :0.88-5.08) and 2.0 (CI:0.726-5.508). In addition, TMJ ID patients were divided into two groups as anterior disc displacement with reduction (ADDWR) and anterior disc displacement without reduction (ADDWOR) and compared with the controls. The TT and CT genotypes were more prevalent than the CC genotype in ADDWR patients compared to the control group with a risk factor of 3.85 (CI:0.927-16.048) and 3.75 (1.02-13.786), respectively. We found that, among ADDWR patients, the T allele is a risk factor both in homozygous and heterozygous carriers (p < 0.052, p < 0.036). CONCLUSION: The results of the study indicate a potential role for the MATN3 rs28598872 polymorphism in the pathogenesis of TMJ ID.

Effect of voxel size on accuracy of cone beam computed tomography-aided assessment of periodontal furcation involvement.

OBJECTIVE: To assess the accuracy of cone beam computed tomography (CBCT) images obtained at different voxel sizes in detecting ligature-induced furcation involvement. STUDY DESIGN: Furcation lesions were prepared in 36 molar teeth in rats, and 24 intact teeth served as controls. CBCT Kodak 9000 images at three different voxel sizes were acquired: 0.076 mm, 0.100 mm, and 0.200 mm. Four observers assessed 3 sets of images using a 5-point evaluation scale. κ-Coefficients were calculated for intra- and interobserver agreement. Receiver operating characteristic analysis measured the true positive rate (TPR), true negative rate (TNR), and area under the curve (AUC). Accuracy values were compared by using Mood's Median Chi-Square (α<0.05). RESULTS: Intra- and interobserver agreement ranged from 0.600 to 0.999 and from 0.366 to 0.573, respectively. Highest median AUC and true positive rate (TPR) values were obtained for voxel size of 0.076 mm. The highest median TNR values were obtained for the voxel size 0.1 mm. There were no significant differences (P≥.05) among the median AUC, TPR, or TNR values for the 3 different CBCT voxel sizes. CONCLUSIONS: Given the limitations of this study, all voxel sizes performed similarly in the detection of furcation involvement.

Subgingival Epstein-Barr and cytomegalovirus occurrence in pregnancy gingivitis.

BACKGROUND: Although recent studies focused on the role of human herpesviruses in various types of periodontal disease, there was a lack of information in these reports regarding the role of pregnancy gingivitis. The aim of this study is to determine the correlation between pregnancy and the subgingival virus presence and their relationship with clinical parameters. METHODS: Seventy pregnant and 40 non-pregnant women were examined for gingival and plaque indices, bleeding on probing (BOP), and clinical probing depths (PDs) from the whole dentition. Subgingival plaque samples were obtained from sites showing signs of gingivitis and healthy sites. The polymerase chain reaction methodology was used to detect cytomegalovirus (CMV) and Epstein-Barr virus (EBV) from plaque samples. RESULTS: Our results show that gingivitis lesions in 27 (38.6%) and 10 (14.3%) pregnant patients were positive for EBV and CMV, respectively. In the non-pregnant group, EBV and CMV were detected in six (15%) and eight (20%) lesions, respectively. A statistically significant difference (P <0.01) was found between the subgingival occurrence of EBV in the two groups. In gingivitis sites, clinical PDs were affected by gestation (P <0.001) and the occurrence of EBV (P <0.001). In healthy sites, clinical PDs were affected by gestation (P <0.05), and BOP was affected by the occurrence of CMV and EBV (P <0.001). CONCLUSION: Our data indicate that pregnancy increased the risk of the presence of subgingival EBV in pregnant women by 3.647 times more than in non-pregnant women.

Periodontal treatment needs and prevalence of localized aggressive periodontitis in a young Turkish population.

BACKGROUND: The purpose of this study was to investigate the prevalence of localized aggressive periodontitis (LAgP) among students aged 13 to 19 years at public schools in Ankara. METHODS: A total of 3,056 students (1,563 females and 1,493 males) participated in the study. All students were examined at their schools and their mouths coded according to the recommendations of the Community Periodontal Index of Treatment Needs (CPITN) using a mirror, a World Health Organization 621 ball-tip probe, and daylight for illumination. Among the students examined, 170 had two or more sextants or teeth with code 3 or one sextant with code 4 and were scheduled for radiographs and a full clinical examination. The additional criteria for the diagnosis of LAgP were good general health, radiographically determined bone loss around the first molars bilaterally, and the bone loss must be unproportionally extensive with respect to the low levels of plaque and calculus, contrary to what is usually observed in chronic periodontitis. RESULTS: Among the 3,056 students screened, 170 were scheduled for further examination, and 18 (10 females and eight males) were diagnosed with LAgP. Of 18,336 sextants examined, 6,575 required scaling, and 63 required scaling and further complex treatment. CONCLUSION: The prevalence of LAgP was 0.6%, with a female/male ratio of 1.25:1.