Porphyromonas gingivalis enhances the senescence-induced increase of 5-alpha reductase in gingival fibroblasts.

OBJECTIVES: Aging is characterized by chronic inflammatory activity. Senescent cells increase with chronic inflammation and age-related pathologies, including periodontal disease. As a critical regulator of tissue inflammaging, we hypothesized that 5α reductase (5αR) is associated with periodontal disease and bacteria-induced senescence in gingival fibroblasts. MATERIALS AND METHODS: We recruited 36 patients with periodontitis, measured 5αR immunohistochemically before and after periodontal treatment, and compared the expression of 5αR in gingival biopsies from 12 healthy individuals. We then tested the impact of Porphyromonas gingivalis on gingival fibroblasts treated with or without D-galactose-induced cell senescence. We treated primary gingival fibroblasts with D-galactose-supplemented media (0 µM, 50 µM, 100 µM, 1 mM, 10 mM, 50 mM) to induce senescence. The expression of type 1 and type 2 5αR was analyzed with real-time PCR and immunocytochemistry. The levels of IL-6, IL-8, TNF-α, and MCP-1 in fibroblast cultures were evaluated by multiplex immunoassay. RESULTS: In gingival biopsies from patients with periodontal disease, the expression of 5αR was significantly higher than in samples from individuals without periodontal disease (p < 0.001). Periodontal treatment significantly reduced the expression of 5αR in gingival tissues (p < 0.001) to levels comparable in healthy individuals. Gingival fibroblasts exposed to D-galactose-supplemented media had a dose-dependent and significant increase in 5αR expression (p < 0.001). P. gingivalis caused statistically higher type 1 and type 2 5αR expression in gingival fibroblast cells. This effect was exacerbated by the lower doses of D-galactose (p = 0.037). Cells infected with P. gingivalis produced significantly higher levels of IL-6, IL-8, TNF-α, and MCP-1 (p < 0.05) regardless of the D-galactose exposure. CONCLUSION: The results suggested that 5αR plays a role in periodontal disease and mediates the senescence-induced response to P. gingivalis in gingival fibroblasts. CLINICAL RELEVANCE: Periodontal diseases and aging can increase the production of 5-alpha reductase in the gingival tissue.

Association between androgenetic alopecia and periodontitis.

AIM: Androgenic alopecia (AGA) is men's most common form of hair loss. It is affected by changes in the expression and activity of 5αR and the metabolism of testosterone and DHT. There is an association between AGA and systemic inflammatory diseases. We hypothesized that there is an association between AGA and periodontal disease, as inflamed gingiva and periodontal fibroblasts have been shown to express more 5αR. Thus, this study aimed to evaluate the relationship between periodontal disease and AGA and the potential effect of aging on this association. MATERIALS AND METHODS: Out of a cohort of 1088 individuals, 385 white males aged 25-65 with similar socioeconomic levels and without systemic disease were included. Periodontitis was defined using NHANES data. AGA was evaluated using the Norwood-Hamilton scale. The relationship between AGA, periodontal disease severity, and age was assessed. RESULTS: There was a correlation between age and baldness (r = .421, p < .001). There was a significant correlation between AGA and periodontal disease in younger patients aged 25-34 and 35-44. (p < .042 and p < .036, respectively). There was no significant correlation between AGA and periodontal disease in the 45-54 and 55-65 age groups (p > .05). CONCLUSION: There may be a relationship between periodontal disease and AGA in the 25-44 age range, suggesting that this association starts at an early age in adulthood.

The Evaluation of Different Polishing Techniques' Effects on the Post-operative External Staining of Enamel in Primary and Permanent Tooth.

Objective This study aimed to examine patient complaints on recoloration development after polishing applications in primary and permanent teeth that differed in enamel composition and to determine the ideal polishing method. Methods A total of 30 permanent upper incisors and 30 primary molars were randomly divided into three groups of 10 using three different polishing techniques. Each polishing method (rubber, brush, and air polishing) was applied to the test surface of its own group. Milk and coffee were used in the coloring processes. A spectrophotometer was used for color measurements. Color change (∆E) was calculated between control and test surfaces and between the three measurement points. Results In the primary teeth's test surfaces, the rubber and brush groups were significantly more colored than the air-polishing group, when compared between after polishing and after coloration (p ˂ 0.05). Furthermore, the color difference of the permanent teeth between the initial measurements and after coloration was significantly higher in the rubber group's test surface compared to the air-polished group (p ˂ 0.05). The average ∆E values in both primary and permanent teeth were as follows: rubber > brush > air polishing. Conclusions Compared to rubber or brush polishing, air polishing seems safer to avoid predisposition to postoperative enamel discoloration. Primary teeth are more colored than permanent teeth. The effect of polishing on postoperative coloring should always be considered, and air polishing should be preferred whenever possible.

Effect of low-level laser on guided tissue regeneration performed with equine bone and membrane in the treatment of intrabony defects: a clinical study.

OBJECTIVE: The purpose of the present study was to evaluate the clinical results of guided tissue regeneration (GTR) after the application of equine bone and membrane alone or combined with low-level laser therapy (LLLT) for the treatment of periodontal defects. MATERIALS AND METHODS: This study was an intra-individual longitudinal study of 6 months' duration conducted using a split-mouth and randomized design. In 13 periodontitis patients with bilateral intrabony periodontal defects, while one defect site was treated with GTR plus LLLT (1064 nm, 100 mW, with energy density of 4 J/cm(2)), the contralateral defect site was treated with guided GTR alone. GTR was performed with a combination of equine bone and membrane. LLLT was used both intra- and postoperatively. Clinical probing depth (PPD), clinical attachment level (CAL), clinical gingival recession level (REC), plaque index (PI) score, and sulcus blooding index (SBI) score were recorded at the time of surgery, and at the 3rd and 6th months after operation. RESULTS: The treatment of periodontal intrabony defects with equine bone and membrane in the operation of GTR alone or GTR plus LLLT in combination led to statistically significant PPD reduction, CAL gain, and lower SBI score at the end of the study (p<0.05). In addition, between the two groups, GTR plus LLLT resulted in statistically significant lower REC (p=0.025), lower SBI (p=0.008) score, more reduction of PPD (p=0.009) and CAL gain (p=0.002) compared with GTR alone at 6th month control. CONCLUSIONS: This study showed that GTR is an effective treatment for periodontal regeneration, and that LLLT may improve the effects of GTR in the treatment of periodontal defects.

Clinical effects of Nd:YAG laser applications during nonsurgical periodontal treatment in smoking and nonsmoking patients with chronic periodontitis.

OBJECTIVE: The purpose of this study was to compare the clinical efficacy of nonsurgical periodontal treatment with and without Nd:YAG laser (NDL) applications in smoking and nonsmoking patients with moderate chronic periodontitis (CP). MATERIALS AND METHODS: The study population consisted of 52 patients with generalized moderate CP. The study compared the clinical effects of scaling and root planing (SRP) and SRP plus NDL in periodontal pockets measuring between 4 and 6 mm of smoking and nonsmoking patients with CP. The study patients were divided into four groups: Group 1: test teeth in smoker patients (ST; n=52 teeth); Group 2: placebo teeth in smoker patients (SP; n=52 teeth); Group 3: test teeth in nonsmoker patients (NST; n=52 teeth); and Group 4: placebo teeth in nonsmoker patients (NSP; n=52 teeth). Clinical examinations were performed immediately before SRP (the baseline) as well as 1 month (R1) and 6 months (R2) after treatment. RESULTS: The recovery for pocket depth (PD), gingival index (GI), and gingival crevicular fluid (GCF) volume in the NST group was higher than in both smoker groups (p<0.05). Additionally, the changes for each of these parameters in the NSP group were higher than for the SP group (p<0.05) at R1 and R2. SRP plus NDL application versus SRP application alone did not lead to significant differences in any clinical parameters or in GCF volume between the two groups of patients who smoked (p>0.05), whereas statistically significant differences existed for PD between nonsmoker groups at R1 and R2 (p<0.05). CONCLUSIONS: Our results supported the idea that NDL applications provide additional benefits in the periodontal treatment of smokers.

Effect of 1,064-nm Nd:YAG laser therapy on GCF IL-1ß and MMP-8 levels in patients with chronic periodontitis.

The aim of this study was to evaluate the long-term effects of a combined periodontal treatment of scaling and root planing (SRP) and Nd:YAG laser (NDL) in chronic periodontitis (CP) patients. This was accomplished by determining the periodontal indices and the interleukin-1beta (IL-1ß) and matrix metalloproteinase-8 (MMP-8) levels of the gingival crevicular fluid (GCF). This study was performed according to a random split-mouth-design, controlled clinical trial for sulcular debridement on 40 teeth from 20 patients with generalized moderate chronic periodontitis. The periodontal healing outcomes were compared after periodontal treatment with either SRP + NDL at 1 W (test side) or SRP (control side). Plaque index (PI), gingival index (GI), probing pocket depth (PPD), and clinical attachment level (CAL) were recorded, and samples of gingival crevicular fluid (GCF) were taken at baseline and post-therapy (3 and 9 months after treatment). The GCF samples were analyzed for IL-1ß and MMP-8. There was postoperative improvement of all clinical parameters in both groups, but test side GI, PPD, and CAL recovery was higher than that of the control side (p < 0.05). Although levels of IL-1ß and MMP-8 in GCF after treatment were lower in the test side than the control side, there was not a statistically significant difference (p > 0.05). In the long term, we found that SRP + NDL treatment of periodontal pockets was more effective than SRP alone in reducing PPD, CAL, GI, and GCF values.

Evaluation of pain levels after Nd: YAG laser and scalpel incisions: an experimental study in rats.

BACKGROUND: Postoperative pain is a recognized sequel of periodontal surgery. The pain experience has been shown to peak in the first 24 hours following the procedure, and to decrease rapidly in subsequent days. The aim of the present study was to evaluate the pain levels following scalpel- and laser-incision of rat hind paws. METHODS: The study was carried out on 10 albino Wistar male rats. Rats were randomly assigned to two groups: Group I (n = 5, laser surgery), or Group II (n = 5, conventional surgery with scalpel). For measuring mechanical hyperalgesia, the nociceptive threshold of the hind paw after mechanical stimulation was quantified using a Basile algesimeter. The measurements were done before the surgery and on the postoperative 1(st), 2(nd), 3(rd), and 7(th) days. RESULTS: While the pain levels of the groups were similar before the surgical procedures, the laser-applied rats had significantly fewer nociceptive thresholds of the hind paw after mechanical stimulation compared with the scalpel-incised rats on the postoperative 1(st), 2(nd), 3(rd), and 7(th) days. Functional complications were not observed in the laser groups at three days after the surgery. CONCLUSION: The results suggested that, for soft tissue surgery, Nd: YAG lasers have often led to shorter operative times, less pain, and fewer postoperative adverse events.

Genetic variation of myeloperoxidase gene contributes to aggressive periodontitis: a preliminary association study in Turkish population.

Myeloperoxidase (MPO) is a lysosomal enzyme found in the azurophilic granules of polymorphonuclear leukocytes. It is involved in the defense against periodontal bacteria, and is also able to mediate inflammatory tissue destruction in aggressive and chronic periodontitis. The aim of this study was to explore the association between MPO-463G/A gene polymorphism and aggressive periodontitis (AgP) and chronic periodontitis (CP). The study included 147 subjects. Probing depth (PD), clinical attachment loss (CAL), plaque index (PI), and gingival index (GI) were recorded as the clinical parameters. Genomic DNA was obtained from the peripheral blood of 32 subjects with AgP, 25 with CP, and 90 reference controls. We genotyped the MPO-463G/A polymorphism using the PCR-RFLP method. All data were analyzed using SPSS version 13.0 for windows. There were no significant differences between the CP patients and controls regarding MPO-463A/G gene polymorphism either in terms of allele frequency or genotype frequency of MPO-463A/G. However, either in terms of allele frequency or genotype frequency of MPO-463A/G, there were significant differences between the AgP patients and the controls. In conclusion, our data suggest that MPO-463G/A may be associated with increased risk of aggressive periodontitis in Turkish patients.

Association between TNF-alpha, TGF-beta1, IL-10, IL-6 and IFN-gamma gene polymorphisms and generalized aggressive periodontitis.

OBJECTIVE: The aim of this study was to investigate links among cytokine genetic variants and generalized aggressive periodontitis (GAgP). METHODS: Thirty-five patients with generalized aggressive periodontitis and 85 healthy controls without periodontitis were included in the study. Probing depth (PD), clinical attachment loss (CAL), plaque index (PI), and gingival index (GI) were recorded as clinical parameters. Polymorphisms of IL-6, IL-10, IFN-gamma, TGF-ss1 and TNF-alpha gene were analysed using the polymerase chain reaction sequence-specific primer method (PCR-SSP). RESULTS: No significant differences were observed for IL-6, IL-10, IFN-gamma, and TGF-ss1 cytokine polymorphisms, from the genotype distribution and allele frequency, between GAgP and healthy control groups. In contrast, significant differences were observed in the TNF-alpha gene polymorphism between GAgP and healthy control groups (P = 0.002). CONCLUSION: Our data suggest that TNF-alpha (-308) may be associated with the development of generalized aggressive periodontitis. These results should be replicated in a larger and more diverse population of patients diagnosed with generalized aggressive periodontitis to determine of these findings are generalizable.

Comparative evaluation of Nd:YAG laser and fluoride varnish for the treatment of dentinal hypersensitivity.

INTRODUCTION: Various methods and materials are used in the treatment of dentin hypersensitivity. The aim of this randomized prospective controlled clinical trial was to evaluate and compare the desensitizing effects of the neodymium-doped yttrium aluminium garnet (Nd:YAG) laser and fluoride varnish by considering the degree of pre- and posttreatment pain, discomfort, and functional complications. METHODS: Twenty patients with clinically diagnosed cervical dentin hypersensitive teeth were included and randomly allocated to either the application of fluoride varnish (group fluoride) or Nd:YAG laser (100 mJ, 20 Hz; group Nd:YAG). The assessment of pain and discomfort was performed by a visual analog scale after an air blast at baseline, immediately after treatment, and at patient visits on weeks 1, 2, 3, and 4. RESULTS: Laser treatment resulted in significant improvements of discomfort immediately after treatment and after 1 week. At the 2-, 3-, and 4-week examination, the discomfort in group fluoride decreased up to nearly 75% to 85% of baseline scores, whereas the effect of the laser stayed nearly unchanged. The visual analog scale scores for pain at 4 weeks examination were significantly lower in the fluoride group compared with those in the laser group (p < 0.05). CONCLUSIONS: Nd:YAG laser is a suitable tool for the immediately successful reduction of dentinal hypersensitivity and has better patient satisfaction and shorter treatment time.

Effects of different blood groups on the reproduction of periodontal pocket bacteria.

BACKGROUND: Many studies have been conducted proving the relation between different blood groups and certain diseases. It was claimed in these studies that H pylori showed different distribution according to different blood groups. In dentistry, the relation between blood groups and dental diseases was investigated in a limited number of studies and it was concluded that there might be a relation between them. The aim of the present study was to determine whether the bacteria isolated from the periodontal pockets of individuals with periodontal diseases indicated differences in CFU amounts to form colonies in different ABO blood groups. METHODS: Bacterial samples obtained from the individuals with periodontal diseases from the worst affect sites were inoculated into culture media formed by blood taken from 32 individuals who were systemically and periodontally healthy and who had different blood groups. The colony numbers of these bacteria were observed. RESULTS: Although periodontal pocket bacteria formed colonies in different numbers in different ABO blood groups (p < 0.05), no statistically significant difference was determined in the reproduction of these bacteria in different Rh blood groups and different sexes (p > 0.05). CONCLUSION: Different ABO blood groups may show differences in significant rates in the colonisation numbers of the bacteria that are the main cause of periodontal diseases.

In vivo assessment of zinc deficiency on craniofacial growth in a rat model.

OBJECTIVES: The aim of this study was to investigate the effects of low levels of zinc intake on the rat mandible and maxilla during growth and to compare these results with those of zinc-containing rats. METHODS: The study was carried out on 14 Sprague-Dawley rats. The rats were randomly divided into two groups. Group I rats were fed with a Zn-deficient diet, and Group II rats with a Zn-containing diet. At the end of the fourth week on the experimental diet, all the rats were killed and blood samples were taken. Serum Zn levels were measured by atomic absorption spectrophotometry. Then, the skulls and mandibles were freed from soft tissues and measurements were made on the dry skulls, the mandibles, and teeth in both of the two groups. RESULTS: The zinc-deficient group showed a significantly lower value in dry skull, mandible, and teeth measurements when compared with those of the Group II. CONCLUSIONS: Changes in zinc intake might exert an effect on the growth of craniofacial structures. A low-zinc diet during adolescence might slow bone and teeth growth and enhance the risk of oral, periodontal, and orthodontic problems in later years.

The changes in the T-lymphocyte subsets in a population of Turkish children with puberty gingivitis.

OBJECTIVE: The aim of the study was to investigate the number of CD4 and CD8 T lymphocytes, analyse subjects with gingivitis and those without, and determine the role of T lymphocytes in the pathobiology of puberty gingivitis. MATERIAL AND METHODS: Fifty individuals with and without puberty gingivitis were recruited for this study. The CD4(+) and CD8(+) T-lymphocyte counts were determined using flow cytometry on the biopsy samples, and the CD4(+)/CD8(+) ratio was calculated. At the same time, periodontal index scores were recorded to assess the periodontal status. Acquired data were analysed statistically using a paired t-test to compare laboratory values obtained before and after the treatment in individuals with puberty gingivitis and disease-free individuals. In addition, Pearson's correlation analysis was performed to investigate the relation between laboratory values and clinical measurements. RESULTS: The CD4(+)/CD8 ratio in gingival tissues obtained from test group was significantly higher (P < 0.05) than that found in the gingival tissue obtained from control group. We found that the CD4(+) and CD8(+) lymphocyte counts continued to increase significantly (P < 0.001) and the CD4(+)/CD8(+) ratio continued to drop significantly (P < 0.05) after treatment in test group. CONCLUSIONS: T lymphocytes could play a significant role in the pathobiology of puberty gingivitis.

An evaluation of different treatments for recurrent aphthous stomatitis and patient perceptions: Nd:YAG laser versus medication.

OBJECTIVE: The aim of this randomized controlled clinical trial was to determine the anxiety levels of patients with recurrent aphthous stomatitis (RAS) prior to therapy with the Nd:YAG laser or medication, and to compare the effects of these different treatment methods on the degree of post-treatment pain, discomfort, and functional complications (eating and speech) experienced. MATERIALS AND METHODS: Twenty patients with RAS-related oral problems were included in the study. Levels of pre- and post-treatment pain and functional complications were assessed at patient visits on days 1, 4, and 7. RESULTS: The results indicated that patients treated with the Nd:YAG laser had less post-treatment pain and fewer functional complications, and reported immediate relief of pain and faster healing (p +/- 0.05). However, only after 5 d was there a significant reduction in the pain levels of the patients treated with medication. CONCLUSION: Our results suggest that the Nd:YAG laser has better patient acceptance, shorter treatment time, and lower rates of pain and post-treatment adverse events among patients with RAS.

Effect of Nd: YAG laser irradiation on the treatment of oral malodour associated with chronic periodontitis.

AIM: To investigate, using a randomised-controlled, single clinical trial whether treating periodontitis with non-surgical periodontal treatment procedures and laser applications can decrease the effect of oral malodour and compare the effectiveness of the different therapies. METHODS: Sixty patients suffering from chronic periodontitis and complaining of oral malodour were included in the study. The parameters measured included organoleptic scoring, volatile sulphur compound (VSC) levels, gingival index, plaque index, probing depth and clinical attachment levels before and after the different treatment procedures (oral hygiene instructions, scaling-root planing-SRP and subgingival Nd: YAG laser irradiation). RESULTS: There were significant relationships between oral malodour and the specific periodontal parameters. For all patients, there were statistically significant (p < 0.05) decreases in the clinical index scores and VSC values after all treatments. Although the VSC values decreased in all groups after treatment, laser treatment alone did not cause as large decreases as that achieved by SRP and SRP + laser irradiation. CONCLUSION: The results confirmed that in the population studied, oral malodour levels were significantly reduced after treating chronic periodontitis. The data indicated a possible adjunctive role for Nd: YAG lasers in periodontal therapy and treatment of oral malodour.

The influence of type-1 diabetes mellitus on dentition and oral health in children and adolescents.

PURPOSE: The present study is to investigate the effects of type 1 diabetes mellitus on dentition and oral health for children and adolescents. MATERIALS AND METHODS: The investigation was carried out on 100 subjects. The first group consisted of 50 subjects with type 1 diabetes mellitus (21 females, 29 males), age 9+/-0.14 years; In the second group, there were 50 healthy subjects who did not suffer from any systemic disease (25 females, 25 males), age 9+/-0.11 years. The subjects were evaluated and divided into two groups of 5-9 years old, and 10-14 years old. The dentition of all participants was examined. Besides, the DFS/dfs index, oral hygiene conditions were evaluated, as well as the plaque index (PI), gingival index (GI) and calculus index (CI). The data obtained from each group were compared statistically. RESULTS: When compared to the non-diabetic group, we observed that dental development was accelerated until the age of 10 in the diabetic group, and there was a delay after the age of 10. The edentulous interval was longer in the group with type 1 diabetes mellitus. This was accompanied by a high ratio of gingival inflammation. Gingival inflammation was 69.7% in the group of 5-9 year-old, and 83.7% in the group of 10-14 year-old with type 1 diabetes mellitus. Though there was a greater loss of teeth in the group with type 1 diabetes mellitus, there were more caries in the control group. The PI, GI and CI values showed an increase with aging in favor of the group with type 1 diabetes mellitus. There was statistically significant difference in PI, GI and CI between the control and type 1 diabetes mellitus groups for 10-14 year-old patients (p<0.001). CONCLUSION: The findings we obtained showed that type 1 diabetes mellitus plays an important part in the dentition and oral health of children and adolescents.

The relationship between teething and handedness.

The aim of this study was to evaluate the role of tooth eruption sequences as an indicator of handedness. The investigation was carried out on 92 healthy children. The questionnaire form was filled out for each child. The form consisted of two parts. In the first part there were questions to determine the demographic features of the children. The second part consisted of the questions to clarify the eruption time and sequence of first primary teeth. Hand preference was evaluated by placing colored pencils directly in front of the child, who was asked to write an "X" on a piece of paper with each pencil. According to left-, right-, and indetermined handedness, all children regardless of sex were divided into three groups. The data were analyzed for statistical evaluation using tests for the difference between two population propositions. The mean eruption time of the first tooth in children was 7.5 +/- 1.7 months. The eruption time was found similar in both groups. No statistically significant difference was determined between the teeth eruption time and handedness (p >.05). The first tooth erupted was generally the lower central incisor. There was no difference tooth eruption and sex, gestation week (p >.05). No statistically significant difference was found between the teeth eruption time and sequence of the primary teeth (p >.05). There was statistically significant difference between sequence of the tooth eruption and handedness (p <.001). Consequently, the tooth eruption sequences may play an important role as an indicator in handedness.

The Effect of ABO Blood Types on Periodontal Status.

OBJECTIVES: The purpose of the present study was to determine whether there was a relationship between periodontal diseases and ABO blood groups. METHODS: This epidemiological study was carried out on 1351 subjects who were randomly selected from individuals referred to the Faculty of Dentistry clinics for periodontal treatment or for other reasons regarding dental health. The study based on periodontal condition, blood group, and medical history. The subjects were divided into three groups as those with gingivitis, periodontitis, and the healthy ones. The effects of blood subgroups on periodontal health, gingivitis and periodontitis were investigated separately. RESULTS: A relatively higher percentage of A group patients was found in gingivitis group and relatively higher percentage of O group patients was found in periodontitis group. A significant relationship was also determined between Rh factor and gingivitis. CONCLUSIONS: ABO blood subgroups and Rh factor may constitute a risk factor on the development of periodontal disease. However, long-term studies are needed to make a more comprehensive assessment of the effects of ABO group on periodontal diseases.

New evidence of premature oxidative DNA damage: mitochondrial DNA deletion in gingival tissue of patients with periodontitis.

BACKGROUND: Overproduction of reactive oxygen species (ROS) causes increased oxidative stress in gingival tissue. It has been generally accepted that increased oxidative stress might contribute to additional damage of lipids, proteins, and DNA molecules. The mitochondrial DNA (mtDNA) mutation is a superb biomarker of oxidative damage. The aim of the present study was to investigate the mtDNA deletions in the gingival tissue of patients with periodontitis and to explain the correlations between mtDNA deletion in gingival tissue and clinical parameters of periodontitis and age. METHODS: Gingival tissue and blood samples were collected from 30 patients with chronic periodontitis (CP group) and 30 healthy control subjects (H group). To determine the clinical condition of each subject, the plaque index, gingival index, clinical attachment level, and probing depth were measured. Using the polymerase chain reaction (PCR) method, we examined the 7.4- and 5-kbp mtDNA deletions in tissue and blood samples. Three different pairs of PCR primers were used in this study. RESULTS: In this study, we did not detect any deletions in blood DNA samples in either the CP or H group. Also, the 7.4-kbp mtDNA deletion was not detected in gingival tissues of subjects. However, the 5-kbp mtDNA deletion was detected in 24 of the 30 subjects (80%) in the CP group and was not detected in the H group (0%). Significant correlations were found between the occurrence of the 5-kbp mtDNA deletion and all clinical parameters (P <0.01). A similar correlation was found between the occurrence of the 5-kbp mtDNA deletion and age (P <0.05). CONCLUSIONS: The overproduction of ROS by activated polymorphonuclear leukocytes in chronic inflammation may lead to premature oxidative damage of the mtDNA. In this study, the occurrence of the 5-kbp mtDNA deletion in 24 periodontitis subjects may be evidence of premature oxidative DNA damage.

The changes in T lymphocyte subsets following periodontal treatment in patients with chronic periodontitis.

OBJECTIVE: The aim of this study was to determine whether there was any change in T-lymphocyte subsets in patients with chronic periodontitis after applying different periodontal treatment methods. PATIENTS AND METHODS: Twenty-four patients with chronic periodontitis were included in the study. In every phase of the treatment (pretreatment, initial treatment, curettage and flap operations) the biopsy samples were taken from the gingival tissues at sites of chronic periodontitis. Then CD4(+) and CD8(+) lymphocyte and CD4(+)/CD8(+) ratio values were determined using flow cytometry in the biopsy samples. At the same time, gingival pocket depth, Löe-Silness gingival index, and Silness-Löe plaque index scores were recorded to assess the periodontal status in patients. To determine the correlation between the clinical measurements and the laboratory results obtained before the treatment, after initial treatment, after curettage and after flap operations, we conducted an analysis using a paired t-test. RESULTS: Flow cytometry findings in the patients with chronic periodontitis showed that CD4(+) and CD8(+) lymphocyte values before treatment were under the normal value and the CD4(+)/CD8(+) ratio was within the normal distribution interval. The CD4(+)/CD8(+) ratio decreased postcurettage and postflap operation. This decrease was statistically significant (p < 0.001). The CD4(+) and CD8(+) lymphocyte values were increased postcurettage and postflap operation. This increase was also statistically significant (p < 0.001). CONCLUSIONS: These findings suggest that local immune response was poor in the patients with chronic periodontitis. CD4(+) and CD8(+) T-lymphocytes could play a significant role in chronic periodontitis pathobiology.