Progression of periodontal disease in the second/third molar region in subjects with asymptomatic third molars.

PURPOSE: To assess the change in periodontal status over time by periodontal probing depth (PD) in the third molar region. SUBJECTS AND METHODS: The data for these analyses are part of a study of subjects enrolled with 4 asymptomatic third molars with adjacent second molars in an institutional review board-approved longitudinal trial. Full mouth periodontal probing was conducted to determine periodontal status at baseline and follow-up. Panoramic radiographs were analyzed for angulation and degree of eruption of third molars. Subjects were categorized as those who exhibited at least a 2 mm change in periodontal PD between baseline and follow-up in the third molar region, the distal of a second molar or around a third molar, and those who did not exhibit a 2 mm or greater change. Subjects with and without changes in PD were compared with Cochran-Mantel-Haenzsel statistics. Level of significance was set at 0.05. RESULTS: Data from 254 subjects with at least 2 annual follow-up visits were available for analysis. Mean age at baseline was 27.5 years. Median follow-up from baseline to the second follow-up visit was 2.2 years (interquartile range 2.0, 2.6). At enrollment, 59% of the subjects had at least 1 PD > or =4 mm in the third molar region, one quarter had a PD > or =5 mm. Twenty-four percent of the subjects had at least 1 tooth that had an increased PD > or =2 mm in the third molar region at follow-up. If subjects had at least 1 PD > or =4 mm at baseline, 38% had at least 1 PD deepen by 2 mm or more at follow-up. Only 3% of those who had all teeth with a PD of less than 4 mm at baseline exhibited a change of > or =2 mm (P < .001). CONCLUSION: Increased periodontal PDs > or =2 mm were often found in the third molar region for asymptomatic subjects with at least 1 PD > or =4 mm at enrollment, clinical measures that indicated increased periodontal pathology, and a deteriorating periodontal condition.     

Reliability of third molar probing measures and the systemic impact of third molar periodontal pathology.

PURPOSE: This study examined the reliability of assessing clinical periodontal measures on third molars, and the association between oral inflammation with periodontal pathology including third molars, and systemic inflammation including negative obstetric outcomes. PATIENTS AND METHODS: Reliability of third molar probing depth (PD) was assessed for 41 patients by trained examiners. The data for the association between oral inflammation with periodontal pathology and systemic outcomes were derived from an IRB-approved study, "Oral Conditions and Pregnancy." Full mouth periodontal exams including third molars were conducted at less than 24 weeks of pregnancy. Periodontal status, moderate/severe periodontal disease (15 or more sites PD > or =4 mm) was considered as a possible predictor of systemic inflammation and pre-term birth. The upper quartile of the extent of PD for third molars alone (PD > or =4 mm) also was considered as a possible exposure variable for the same outcomes. Chi-square and t tests were used to determine statistical significance (0.05). Significant predictor variables were included in multivariate models. Unconditional logistic multivariate models were used to derive odds ratios (OR) and 95% confidence intervals (CI). RESULTS: Reliability of PD within 1 mm was excellent, and similar for third molars and non-third molars. Data from 1,020 obstetric patients were available for analysis. Eighteen percent of the patients delivered preterm, at less than 37 weeks. Having moderate/severe periodontal disease excluding third molars, was significantly associated with preterm birth (P = .008). Results were more significant if third molars were included (P = .0005). With multivariate models moderate/severe periodontal disease at enrollment including third molar PD, was associated with preterm birth (OR, 1.7; 95% CI, 1.1, 2.6). If only the extent of third molar PD was considered, odds also were increased for preterm birth (OR, 2.4; 95% CI, 1.1, 5.2). If only the extent of third molar PD was considered at enrollment, odds were increased for serum markers of systemic inflammation, elevated serum CRP, and oxidative stress, 8-isoPGF(2alpha). CONCLUSIONS: Dental examiners could reliably assess clinical periodontal measures on third molars. Third molars should be included in studies of systemic outcomes associated with oral inflammation. Women of child-bearing age should be made aware of the systemic risks of oral inflammation with third molar periodontal pathology.     

Changes in third molar and nonthird molar periodontal pathology over time.

PURPOSE: The purpose of this study was to assess changes in periodontal probing depth (PD) over time for third molar and nonthird molar regions in young adults. PATIENTS AND METHODS: The data were obtained from healthy subjects with 4 asymptomatic third molars, enrolled in an IRB-approved longitudinal trial. Demographic and oral health data were collected at baseline. Full-mouth PD, 6 sites per tooth, was conducted to determine periodontal status at baseline and at longest follow-up. The third molar region was defined as the PD for 6 sites around the third molars and the 2 sites on the distal of the second molars. The nonthird molar region was defined as the remainder of the PD sites in the mouth. The primary outcome measures for this study were the occurrence of a PD greater than or equal to 4 mm and the increase in PD of at least 2 mm in the third molar and nonthird molar regions. Changes from enrollment to longest follow-up were compared by the binomial or McNemar's test. Level of significance was .05. RESULTS: Data from 195 subjects were available, and the median follow-up was 5.9 years (interquartile range [IQ], 4.6 to 6.9 years). Median age at enrollment was 26.2 years (IQ, 22.0 to 34.0 years); 52% were female, 84% were Caucasian, and 10% were African American. The proportion of subjects with at least 1 involved site in nonthird molars increased significantly from baseline to follow-up, 36% to 49% (P < .01), reflecting mostly changes in mandibular nonthird molars, 33% to 48% (P < .01). Of the 122 subjects who presented at baseline with at least 1 PD greater than or equal to 4 mm in the third molar region, the proportion of subjects with at least 1 involved site in nonthird molars increased significantly from baseline to follow-up, 48% to 59% (P = .05), also reflecting mostly changes in mandibular nonthird molars, 44% to 59% (P = .05). CONCLUSION: In this unique longitudinal clinical study of early periodontal disease in young adults, periodontal pathology worsened over time for nonthird molars. This was more likely if PD greater than or equal to 4 mm was detected in the third molar region.     

Third molars and progression of periodontal pathology during pregnancy.

PURPOSE: This study was conducted to evaluate the association between third molar periodontal pathology at enrollment and periodontal disease progression during pregnancy. PATIENTS AND METHODS: The data were derived from patients in an institutional review board-approved prospective study known as the Oral Conditions and Pregnancy (OCAP) study. Demographic, health behavior, and medical history data were obtained from medical records. Full-mouth periodontal examinations of 6 periodontal probing sites for each visible tooth, including third molars, were conducted at less than 26 weeks of pregnancy and within 72 hours postpartum. The primary outcome variable was periodontal progression (4 or more probing sites with at least a 2 mm increase in probing depth (PD), all at least 4 mm deep), between the enrollment and postpartum examinations. The primary predictor variables at enrollment were at least 1 PD >or=4 mm around the third molars, and the upper tertile of the number of third molar probing sites recorded as bleeding on probing (BOP). Bivariate analyses were performed for baseline characteristics. The chi2 test was used to determine statistical significance (P = .05). Significant variables were included in unconditional logistic multivariable models to derive relative risk ratios (RRs) and 95% confidence intervals (CIs). RESULTS: Data from enrollment and term were available for 360 subjects with visible third molars (mean age, 27.3 years; standard deviation, 5.5 years). At the postpartum examination, 122 subjects (34%) demonstrated periodontal progression. These subjects included 74 of the 176 subjects (42%) in whom a third molar PD >or=4 mm was detected at baseline and 48 of the 184 (26%) without third molar PD >or=4 mm (P = .001). Periodontal progression was found in 40 of the 77 subjects (52%) who were in the upper tertile of the number of third molar probing sites exhibiting BOP at enrollment versus 82 of the 203 (29%) in the lower tertiles (P = .0002). In multivariable models, either third molar PD >or=4 mm at enrollment (RR = 1.4; 95% CI = 1.1 to 2.0) or third molar bleeding on probing (RR = 1.7; 95% CI = 1.3 to 2.3) was associated with periodontal disease progression. CONCLUSION: Third molar periodontal pathology appears to be a significant risk indicator for periodontal disease progression during pregnancy.     

Inflammatory mediators and periodontitis in patients with asymptomatic third molars.

PURPOSE: Our goal was to report the detection and levels of gingival crevicular fluid (GCF) inflammatory mediators, sampled at the mesial of 4 first molars and distal of 4 second molars, in 316 patients with asymptomatic third molars. PATIENTS AND METHODS: Levels of GCF inflammatory mediators, interleukin (IL)-1 beta and prostaglandin (PG)E(2), were determined and log transformed for each patient. Z scores were calculated using the mean and standard deviation of the log values for the entire sample of 316 patients. The log mediator levels and Z scores of patients who had probing depths (PDs) less than 5 mm (n = 238) were compared with patients with at least 1 PD equal to or greater than 5 mm (n = 78) on the distal of second molars or around third molars. A periodontal Composite GCF Inflammation Score was calculated for each patient by summing the Z scores obtained for IL-1 beta and PGE(2) for that patient. RESULTS: The levels of GCF IL-1 beta and PGE(2) were higher if a patient had a PD equal to or greater than 5 mm in the third molar region. The Composite GCF Inflammation Score indicated "elevated inflammation" if a PD equal to or greater than 5 mm was found in the third molar region as well. CONCLUSIONS: These data suggest that asymptomatic patients with PD equal to or greater than 5 mm in the third molar region with associated periodontal attachment loss have increased levels of biochemical mediators of inflammation compared with patients with PD less than 5 mm. These findings are consistent with the concept that early periodontitis in young adults that initiates in the third molar region is associated with increases in key inflammatory mediators.     

第三磨牙近中阻生对邻近第二磨牙龈沟液中MMP8和TIMP1的影响

目的:探讨第三磨牙近中阻生对邻近磨牙龈沟液中MMP8和TIMP1的影响。方法:选择64例口腔科就诊的战士,分为4组,A组下颌第二磨牙伴第三磨牙近中阻生,第三磨牙无冠周炎病史,龈瓣颜色正常;B组下颌第二磨牙伴第三磨牙近中阻生,6个月内第三磨牙有冠周炎病史,龈瓣颜色正常;C组下颌第二磨牙伴第三磨牙近中阻生,有冠周炎;D组无下颌第三磨牙,第二磨牙作为对照。收集下颌第二磨牙龈沟液,检测MMP8和TIMP1水平,同时测定第二磨牙龈沟出血指数、探诊深度和菌斑指数等指标。结果:MMP8和TIMP1各组间均有统计学差异(C组>B组>A组>D组)。MMP8/TIMP1 B组和A组之间无明显差别,其余各组间差异有统计学意义。临床指标中,C组的菌斑指数明显高于D组,A、B、C组的探诊深度大于D组。结论:第三磨牙近中阻生在无炎症状态时可引起第二磨牙龈沟液MMP8、TIMP1、MMP8/TIMP1和探诊深度等牙周炎潜在致病因素的变化,出现冠周炎症时变化更加显著。     

Change in third molar angulation and position in young adults and follow-up periodontal pathology.

PURPOSE: This study was designed to assess changes in third molar position and angulation in young adults and the resulting third molar periodontal probing (PD) status. PATIENTS AND METHODS: Data derived from patients with 4 asymptomatic third molars with adjacent second molars enrolled in an institutional review board approved longitudinal trial. Inclusion criteria for the trial dictated that patients be healthy and 14 to 45 years of age. Panoramic radiographs were analyzed for third molar angulation as compared with the long axis of the second molar (mesial/horizontal > or =25 degrees ) and eruption to the occlusal plane. Full mouth PD including third molars was conducted at follow-up. At follow-up, PD > or =4 mm distal of second molars or around third molars was considered important clinically. RESULTS: Data from 237 patients were available. Median age was 25.9 years (interquartile range [IQ], 22.1 years, 32.8 years). With a median follow-up of 2.2 years (IQ, 2.0 years, 3.7 years), 44% of impacted maxillary third and 26% of impacted mandibular third molars changed angulation or position. One third of vertical/distal impacted third molars in both jaws and 11% mesial/horizontal mandibular third molars erupted to the occlusal plane during follow-up from baseline. If mandibular third molar angulation as compared with the long axis of the second molar was mesial/horizontal > or =35 degrees , only 3% erupted to the occlusal plane. At follow-up, 11% of the 125 impacted maxillary third and 29% of the 133 impacted mandibular third molars had PD > or =4 mm. Similarly, 11% of the 307 maxillary third molars at the occlusal plane had PD > or =4 mm, but 51% of the 312 erupted mandibular third molars were affected. CONCLUSION: A change in third molar position or angulation was common. Erupted mandibular third molars were more likely to have PD > or =4 mm.     

Microbial complexes detected in the second/third molar region in patients with asymptomatic third molars.

PURPOSE: Our goal was to report the detection and levels of pathogenic bacteria in subgingival plaque samples taken from the distal of all second molars in 295 patients with asymptomatic third molars. PATIENTS AND METHODS: Data assessing oral health were collected from each of these healthy patients (ASA Classes I and II). Probing depth (PD), at 6 sites per tooth, including third molars, was obtained to determine periodontal status. Subgingival plaque samples were taken from the distal of all second molars before periodontal probing. The presence and levels of 11 bacterial species were determined using whole chromosomal DNA probes and checkerboard DNA-DNA hybridization. Detected bacterial species were grouped into clusters of periodontal pathogens designated as "red" or "orange" complex microorganisms as described by Socransky et al (J Clin Periodontal 25:134, 1998) who found an association of these specific microorganisms with periodontitis. RESULTS: As a group these relatively young patients were periodontally healthy. "Orange and red" complex microorganisms were detected at levels equal to or greater than 10(5) more often if patients had a PD equal to or greater than 5 mm with periodontal attachment loss at the distal of second molars or around third molars at their entry examination. In patients with no PD equal to or greater than 5 mm in the third molar region, "orange and red" complex microorganisms were detected at levels equal to or greater than 10(5) more frequently than would be anticipated in patients with little clinical evidence of periodontal disease. CONCLUSIONS: The clinical findings of increased periodontal PDs and periodontal attachment loss coupled with colonization of periodontal pathogens support the concept that clinical and microbial changes associated with the initiation of periodontitis may present first in the third molar region in young adults.     

Third molar periodontal pathology and caries in senior adults.

PURPOSE: This study was designed to assess the prevalence at enrollment and incidence over 36 months of periodontal pathology and caries affecting third molars in a community-based study of people over the age of 65 years in North Carolina. SUBJECTS AND METHODS: A sub-sample of 818 subjects with dental examinations taken from the Piedmont 65+ Study was available for analysis. All visible teeth were examined. Periodontal probing (PD) measures were taken at 2 sites, mesiobuccal and buccal/facial. Clinical data on caries experience were collected by visual-tactile examination. At enrollment, 342 subjects had at least 1 visible third molar that could be examined. PD measures were available for 276 of these same subjects. The significance of comparisons between third molars and nonthird molars were determined by chi(2) tests and the statistical significance was set at .05. RESULTS: Most of the 342 subjects with at least 1 visible third molar were female (57%) or African American (63%). Mean age was 73 years (SD 5.5 years). Of the 197 subjects with caries experience, third molars were affected in 49% of subjects, less than the 87% in nonthird molars. Third molar caries experience was associated with caries experience on nonthird molar teeth (P < .01). Clinical attachment level (CAL) greater than 3 mm was detected at enrollment in third molars in 68% of subjects, and in nonthird molars in 96%. With one exception, CAL greater than 3 mm in third molars was associated with CAL greater than 3 mm elsewhere in the mouth. Few subjects (17%) had clinical evidence of both caries and periodontal pathology affecting third molars. In this older population of individuals with third molars, 21% were free of periodontal pathology or caries experience. CONCLUSIONS: Data on the prevalence of third molar periodontal pathology and third molar caries experience in an elderly population should be useful to both clinicians and their younger patients when considering the merits of retaining or removing third molars with no evidence of pathology.     

Periodontal pathology associated with asymptomatic third molars.

PURPOSE: We report the prevalence of periodontal probing depth (PD) as a clinical measure of the extent of periodontitis associated with asymptomatic third molars at the initial examination in a cohort of patients enrolled in an institutional review board-approved longitudinal clinical trial. PATIENTS AND METHODS: Three hundred twenty-nine healthy patients were enrolled during a 30-month period. Full mouth periodontal probing that included third molars was conducted to determine periodontal status. Panoramic radiographs were taken to assess the degree of eruption of the third molars and the angulation of third molars compared with the adjacent second molar. Vertical bitewing radiographs were analyzed to detect alveolar bone levels relative to the cementoenamel junction on the distal of second molars. RESULTS: Twenty-five percent (82 of 329) of all enrolled patients, and 34% (14 of 41) of black patients, had at least one PD equal to or greater than 5 mm on the distal of a second molar or around a third molar. PD equal to or greater than 5 mm was associated with periodontal attachment loss of at least 1 mm in every patient; PD equal to or greater than 5 mm was associated with attachment loss equal to or greater than 2 mm in 80 of 82 patients. A higher proportion of patients 25 years old or older had a PD equal to or greater than 5 mm on the distal of second molars or around third molars compared with patients younger than 25 years (33% vs 17%, P =.002). The distals of second molars and third molars in the mandible were affected more often than in the maxilla (25% vs 5%, P =.0001). CONCLUSIONS: Our data indicating that 25% of patients with retained asymptomatic third molars have considerable periodontal pathology in the third molar region were unexpected. National epidemiologic surveys indicate a much lower rate of periodontitis in the population younger than 35 years.     

The effect of low-level laser therapy as an adjunct to non-surgical periodontal treatment

Background: The aim of this study is to evaluate the effect of low‐level laser therapy (LLLT) as an adjunct to non‐surgical periodontal therapy of smoking and non‐smoking patients with moderate to advanced chronic periodontitis. Methods: All 36 systemically healthy patients who were included in the study initially received non‐surgical periodontal therapy. The LLLT group (n = 18) received GaAlAs diode laser therapy as an adjunct to non‐surgical periodontal therapy. A diode laser with a wavelength of 808 nm was used for the LLLT. Energy density of 4 J/cm² was applied to the gingival surface after periodontal treatment on the first, second, and seventh days. Each of the LLLT and control groups was divided into two groups as smoking and non‐smoking patients to investigate the effect of smoking on treatment. Gingival crevicular fluid samples were collected from all patients and clinical parameters were recorded on baseline, the first, third, and sixth months after treatment. Matrix metalloproteinase‐1, tissue inhibitor matrix metalloproteinase‐1, transforming growth factor‐β1, and basic‐fibroblast growth factor levels in the collected gingival crevicular fluid were measured. Results: The primary outcome variable in this study was change in gingival bleeding and inflammation. At all time points, the LLLT group showed significantly more improvement in sulcus bleeding index (SBI), clinical attachment level, and probing depth (PD) levels compared to the control group (P <0.001). There were clinically significant improvements in the laser‐applied smokers' PD and SBI levels compared to smokers to whom a laser was not applied, between the baseline and all time points (P <0.001) (SBI score: control group 1.12, LLLT group 1.49; PD: control group 1.21 mm, LLLT group 1.46 mm, between baseline and 6 months). Transforming growth factor‐β1 levels and the ratio of matrix metalloproteinase‐1 to tissue inhibitor matrix metalloproteinase‐1 decreased significantly in both groups at 1, 3, and 6 months after periodontal therapy (P <0.001). Basic‐fibroblast growth factor levels significantly decreased in both groups in the first month after the treatment, then increased in the third and sixth months (P <0.005). No marker level change showed significant differences between the groups (P <0.05). Conclusion: LLLT as an adjunctive therapy to non‐surgical periodontal treatment improves periodontal healing.     

The oral and systemic impact of third molar periodontal pathology.

PURPOSE: Analyze in pregnant subjects the relationship between third molar periodontal pathology, and subjects' overall periodontal status. Assess also, the associations between postpartum periodontal status by jaw and a systemic impact, preterm birth, or elevated serum C-reactive protein (CRP). PATIENTS AND METHODS: Data were from an IRB-approved study, Oral Conditions and Pregnancy. In this clinical study, full-mouth periodontal examinations including third molars were conducted at greater than 24 weeks of pregnancy and again within 72 hours of delivery. For our analyses, mean periodontal probing depth (PD) by visible tooth and by jaw were calculated at enrollment and postpartum. Subjects were categorized by 3 broad levels of periodontal health, considered the primary outcome variable. The primary predictor variable for levels of periodontal health was the presence or absence of visible third molars. Mean periodontal probing depth in the mandible or maxilla at term was considered an indicator of a possible risk of systemic exposure, increasing the odds of preterm birth, less than 37 weeks gestation, or elevated serum CRP levels. Chi-square and t tests were used to determine statistical significance, .05. Significant predictor variables were included in multivariable models. Unconditional logistic multivariate models were used to derive odds ratios (OR) and 95% confidence intervals (CI). RESULTS: Data from examinations at enrollment and postpartum were available for 1,020 and 891 subjects, respectively. Visible third molars were detected in 405 subjects at enrollment and in 360 subjects at term. No subjects had third molars removed during the study. At enrollment and postpartum, subjects with visible third molars were significantly more likely to have moderate/severe periodontal disease, 23.5% versus 8.5%, and 18.3 versus 9.4%, respectively. Mean PD was significantly greater for maxillary and mandibular molars than for more anterior teeth, P < .01. In both jaws, mean PD tended to be progressively greater from first to third molars. No differences were found in mean PD by jaw. In subjects with visible third molars, adjusting for the severity of mandibular periodontal disease, the level of maxillary periodontal disease was significantly associated with preterm birth, P < .01, OR 2.6 (95% CI 1.1-6.8), or the upper quartile of serum CRP at term, at least 23.0 mg/L postpartum, P = .05, OR 2.5 (95% CI 1.2-5.1). CONCLUSIONS: Subjects' detected levels of periodontal disease were greater at enrollment and postpartum if visible third molars were detected.     

Third molars associated with periodontal pathology in older Americans.

PURPOSE: The study goal was to assess the association between the presence of visible third molars and periodontal pathology in a community-dwelling sample of middle-aged and older adults. MATERIALS AND METHODS: Data were obtained between 1996 and 1999 on 6,793 persons aged 52 to 74 from the Dental ARIC Study, a substudy of the Atherosclerosis Risk in Communities Study. The main independent variable was presence or absence of third molars assessed visually, and the dependent variable was assessment of periodontal disease as measured by pocket depth of 5 mm or greater (PD5+). Periodontal measures included pocket depth, gingival recession, and attachment level on 6 sites per tooth on all remaining teeth. Second molars were compared for periodontal pathology based on the presence or absence of a visible third molar in the same quadrant. Associations were determined using odds ratios and 95% confidence intervals. Weighted multivariable models were fit using logistic regression, and variances were adjusted to account for the clustering of quadrants within persons with the use of SUDAAN (Research Triangle Institute, Research Triangle Park, NC). RESULTS: A visible third molar was associated with 1.5 times the odds of PD5+ on the adjacent second molar, while controlling for other factors associated with the presence of third molars and periodontal disease. Other factors positively associated with PD5+ in the model were male gender, older age, smoking, and irregular and episodic dental visits. CONCLUSIONS: The finding of more severe periodontal conditions associated with visible third molars in these middle-aged and older adults indicates that third molars may continue to have a negative impact on periodontal health well into later life. The relationship between third molars and periodontal disease pathogenesis deserves further study using longitudinal data.     

Risk indicators for third molar caries and periodontal disease in senior adults.

PURPOSE: This study was designed to identify risk indicators for the prevalence at enrollment and incidence over 36 months of periodontal pathology and coronal caries experience affecting third molars in a community-based study of people over 65 years of age. SUBJECTS AND METHODS: Data from a subsample of 810 dentate subjects from the Piedmont 65+ Study were available for analyses. All visible teeth were examined. Periodontal probing measures were taken at 2 sites, mesiobuccal and buccal/facial. Clinical data on caries experience were collected by visual-tactile examination. At enrollment, 340 subjects had at least 1 visible third molar; all were examined for caries experience. Periodontal probing measures were available for 277 of these same subjects. The significance of the possible risk indicators for periodontal pathology and caries affecting third molars was determined by chi(2) tests. Statistical significance was set at .05. Logistic multivariable models were used to derive odds ratios and 95% confidence intervals. RESULTS: African-American subjects were more likely to have visible third molars (P < .01). Caucasian subjects were more likely to have third molar coronal caries experience (P < .01), as were subjects with greater than a high school education and those with a dental visit within 3 years (both P < .01). However, African American subjects were more likely to have periodontal pathology, CALs >/= 3 mm on third molars (P < .01), as were those who used tobacco (P < .01). None of the other risk indicators we studied were associated with progression of periodontal pathology or coronal caries experience on visible third molars. CONCLUSION: In this population study of senior adults, Caucasians and African Americans appear to have different levels of risk for caries experience and periodontal pathology affecting retained third molars.     

The effects of periodontal therapy on intracrevicular prostaglandin E2 concentrations and clinical parameters in pregnancy

BACKGROUND: The increase in circulating levels of progesterone during pregnancy stimulates production of prostaglandins, especially prostaglandin E2, possibly resulting in pregnancy gingivitis. The purpose of this study is to evaluate the influence of prostaglandin E2 concentrations on gingival tissues in pregnancy and to assess its relationship to clinical parameters. METHODS: This study evaluates the effects of periodontal treatment on clinical indices including plaque index, gingival index, probing depth, and gingival crevicular fluid prostaglandin E2 levels of 22 pregnant women in their first, second, and third trimesters. Initial periodontal therapy consisting of scaling, root planing, and oral hygiene instruction was performed at the beginning of the first trimester and repeated each trimester. Prostaglandin E2 concentrations in gingival crevicular fluid were determined using a commercially available enzyme immunoassay kit. The statistical tests used were paired sample test and correlation analysis. RESULTS: The results of the study show that periodontal therapy has resulted in an improvement in clinical parameters (P<0.05). There is also a statistically significant decrease in levels of prostaglandin E2 at the second and third trimesters following periodontal therapy (P <0.001). The correlation between prostaglandin E2 concentrations and clinical parameters is found to be non-significant (P >0.05). CONCLUSIONS: Our data indicate that levels of prostaglandin E2 in gingival crevicular fluid may be used as a marker of gingival inflammation in order to determine the effects of periodontal therapy in pregnancy. Periodontal therapy that is performed throughout the entire pregnancy period may help prevent the threat of pregnancy gingivitis.     

Residual periodontal defects distal to the mandibular second molar 6-36 months after impacted third molar extraction

AIM: This retrospective study investigated the periodontal conditions distal to mandibular second molars 6-36 months after routine surgical extraction of adjacent impacted third molars. METHOD: Subjects were randomly selected by systematic sampling from computer records of 3211 surgical mandibular third molar extractions in the Hong Kong dental teaching hospital. Records and pre-extraction radiographs of the selected cases were retrieved. Selected subjects (n = 283) were invited for an interview followed by a clinical examination. Community Periodontal Index (CPI) protocol was used for the assessment of the general periodontal status (excluding the mandibular second molar of interest, i.e. the subject tooth) followed by a detailed periodontal examination of the subject tooth. RESULTS: In all, 158 subjects, aged 29 +/- 7 years, were examined with only 6% (nine subjects) having a highest CPI score of 4 (excluding the subject tooth), but local periodontal defects were prevalent at the distal surface of subject mandibular second molars: mean probing pocket depth (PPD) was 5.4 +/- 1.9 mm with 67% (106 subjects) exhibiting PPD >or= 5 mm and 23% (36 subjects) exhibiting PPD >or= 7 mm; mean recession was 0.8 +/- 1.0 mm; bleeding on probing 96% and suppuration on probing 5%. Multiple linear regression analysis was used to analyse the effects of 12 independent variables on the PPD at the distal surface of the involved mandibular second molar. Three possible risk indicators (P < 0.001, R2 = 0.27) associated with localised increased PPD at the distal surface of the mandibular second molars were identified: 1) third molar 'mesio-angular' impaction; 2) pre-extraction crestal radiolucency and 3) inadequate post-extraction local plaque control. CONCLUSION: The results suggest that periodontal breakdown initiated and established on the distal surface of a mandibular second molar in the vicinity of a 'mesio-angular' impacted third molar evidenced by pre-extraction crestal radiolucency in association with inadequate plaque control after extraction can predispose to a persistent localised periodontal problem.     

Clinical evaluation of nanocrystalline hydroxyapatite paste in the treatment of human periodontal bony defects--a randomized controlled clinical trial: 6-month results

BACKGROUND: The aim of this study was to compare the clinical outcome of intrabony periodontal defects following treatment with a novel nanocrystalline hydroxyapatite (NHA) paste to open flap debridement. METHODS: Twenty-eight subjects, each displaying one intrabony defect with probing depth (PD) > or =6 mm and radiographic evidence of an intraosseous component > or =3 mm participated in the present study. Subjects were allocated randomly to treatment with NHA paste (test group) or open flap debridement (control group). At baseline and at 6 months after surgery, the following clinical parameters were recorded by a masked examiner: plaque index, gingival index, PD, clinical attachment level (CAL), and gingival recession. RESULTS: A significant improvement in PD and CAL was observed at 6 months after surgery compared to baseline in both treatment groups (P <0.001). At 6 months following therapy, the test group showed a reduction in mean PD from 7.4 +/- 1.3 mm to 3.4 +/- 1.2 mm and a change in mean CAL from 8.0 +/- 1.3 mm to 4.4 +/- 1.7 mm, whereas in the control group the mean PD decreased from 7.4 +/- 0.8 mm to 4.9 +/- 0.9 mm, and mean CAL decreased from 8.1 +/- 1.2 mm to 6.4 +/- 1.3 mm. The intergroup comparison demonstrated significantly more PD reductions (P = 0.012) and CAL gains (P = 0.005) in the test group compared to the control group. CONCLUSION: Treatment of intrabony periodontal defects with NHA paste significantly improved clinical outcomes compared to open flap debridement.     

Ⅱ°根分叉病变患者引导组织再生治疗术前术后龈沟液中糖氨多糖水平的变化

目的　观察Ⅱ°根分叉病变患者引导组织再生治疗术 (guidedtissueregeneration ,GTR)前后龈沟液(gingivalcrevicularfluid ,GCF)中糖氨多糖 (glycosaminoglycans ,GAG)水平变化的同时 ,探讨GCF中GAG能否作为判断GTR术后组织成熟的指标。方法　对 6例Ⅱ°根分叉病变的患牙采用GTR治疗 ,并于手术前 ,手术后 1、2、3、4、5、6周收集GCF。用 0 .1%阿尔辛兰 (Alcianblue)染色 ,分光光度法测定GCF中总的硫酸化GAG及硫酸软骨素 (chondroitinsulfate ,CS)的水平。结果　GTR术后 1～ 2周 ,GCF中CS明显降低 (P <0 .0 5 ) ,然后逐渐升高 ,第 6周恢复到基线水平。而GCF中总的硫酸化GAG则在术后 1周明显升高 (P <0 .0 5 ) ,然后下降 ,到第 6周升高并超过基线水平。结论　GCF中总的硫酸化GAG ,尤其是CS可用作监测牙周伤口愈合和组织再生的一个潜在指标 ,但是否可以用作GTR术后组织成熟的指标 ,还需加大样本并结合病理进行进一步的纵向观察     

Alterations in crevicular fluid flow during healing following gingival surgery

The relationship between gingival crevicular fluid flow and healing after gingival surgery, as assessed by biopsy, cytologic and microbial smears, was evaluated. Eighty-five periodontal pockets from the maxillary anterior and premolar teeth were studied in nine patients. Gingival fluid flow measurements, cytologic and microbial smears were taken weekly from each periodontal pocket for five weeks. The gingivectomy was performed at the first week and the tissue biopsied. Additional biopsies were also taken of selected areas on the fifth week. The results were analyzed to ascertain any correlation between gingival crevicular fluid flow and gingival inflammation during healing. The following conclusions can be drawn:

• 1 Quantity of gingival crevicular fluid, sulcular cytologic and microbial smears can be of value in assessing gingival status.
• 2 A direct relationship exists between the rate of crevicular fluid flow and healing following gingival surgery.
• 3 A healthy crevicular epithelium lining the gingival sulcus appears to function as a barrier, thereby retaining the gingival tissue fluid.