Periodontal tissue reactions to orthodontic extrusion

Orthodontic tooth extrusion is used at crown lengthening procedures or in conjunction with periodontal therapy aimed at eliminating or reducing angular bone defects. A technique for orthodontic extrusion combined with resection of the supracrestal attachment fibers (fiberotomy) was recently proposed as an adjunct to certain restorative procedures. The aim of the present investigation was to analyze reactions of the periodontal tissues to orthodontic extrusion when combined with fiberotomy. In 5 beagle dogs, the mesial roots of the 2nd, 3rd and 4th hemisected mandibular premolar were used as target roots while the distal roots served as reference units. After a baseline examination, an orthodontic extrusion device (stent) was installed and reactivated at 2-week intervals during an 8-week period of active tooth movement. Immediately following the installation of the stent and once every 2nd week, the target roots were exposed to fiberotomy. After the active period, the teeth were retained in their new position for a period of 8 weeks. Clinical, radiographical and histological measurements were performed. The results from the investigation demonstrated that orthodontic extrusion combined with supracrestal fiberotomy resulted in a coronal displacement of the tooth and was associated with pronounced recession of the gingival margin and extensive loss of connective tissue attachment. The degree of gingival recession and the amount of loss of connective tissue attachment were, however, less extensive than the amount of tooth extrusion. Thus, repeated fiberotomy obviously failed to entirely prevent coronal migration of the attachment apparatus. It was also observed that undesired attachment loss had occurred at the reference roots.     

Smoking, a weak predictor of periodontitis in older adults

BACKGROUND: The impact of smoking habits on periodontal conditions in older subjects is poorly studied. AIMS: To assess if a history of smoking is associated with chronic periodontitis and medical history in older subjects. MATERIAL AND METHODS: The medical and dental history was collected from 1084 subjects 60-75 years of age. Smoking history information was obtained from self-reports. Periodontal variables [clinical probing depth (PD)>/=5.0 mm, clinical attachment levels (CALs) >/=4.0 mm], and radiographic evidence of alveolar bone loss were assessed. RESULTS: 60.5% had never smoked (NS), 32.0% were former smokers (FS) (mean smoke years: 26.1 years, SD+/-13.1), and 7.5% were current smokers (CS) (mean smoke years 38.0 years, (SD+/-12.1). The proportional distribution of CAL >/=4.0 mm differed significantly by smoking status (NS and CS groups) (mean difference: 12.1%, 95% confidence interval (CI): 1.5-22.6, p<0.02). The Mantel-Haenszel common odds ratio between smoking status (CS+FS) and periodontitis (>20% bone loss) was 1.3 (p<0.09, 95% CI: 0.9-2.0) and changed to 1.8 (p<0.02, 95% CI: 1.3-2.7) with 30 years of smoking as cutoff. A weak correlation between number of years of smoking and CAL>/=4.0 mm was demonstrated (r(2) values 0.05 and 0.07) for FS and CS, respectively. Binary logistic forward (Wald) regression analysis demonstrated that the evidence of carotid calcification, current smoking status, gender (male), and the number of remaining teeth were explanatory to alveolar bone loss. CONCLUSIONS: A clinically significant impact on periodontal conditions may require 30 years of smoking or more. Tooth loss, radiographic evidence of carotid calcification, current smoking status, and male gender can predictably be associated with alveolar bone loss in older subjects.     

附着体应用于单侧上颌骨缺损修复的模型设计与制作

目的:探讨附着体应用于单侧上颌骨缺损修复的支架设计及制作方法。方法:在健侧余留牙舌面设计制作连续的舌面导板,MiNiSG附着体位于中切牙的近中,与舌面导板相结合。然后在此基础上设计制作赝复体基托,与腭部及舌面板紧密贴合。对制作完成的支架与基托做固位力测试。结果:获得了所设计的附着体支架及赝复体金属基托的实物模型,平均固位力达47N。结论:附着体应用于单侧上颌骨缺损修复在操作技术上切实可行,可增加整个修复体的固位与稳定。     

Treatment of periodontal infections due to anaerobic bacteria with short-term treatment with metronidazole

Abstract In the present report, five selected periodontal patients were treated for 1 week with metronidazole. Two of the patients had their teeth scaled and root-planed the week they received metronidazole. Prior to treatment, B. asaccharolyticus accounted for 41 % of the cultivable isolates and the spirochetes averaged 29 % of the microscopic count in plaque removed from each of four pockets per patient. The presence of these elevated proportions of periodontopathic bacteria combined with the presence of periodontal pockets and attachment loss suggested that the patients were in a state of an active infectious process involving primarily anaerobic bacteria. If this be the case, then antimicrobial therapy directed against these anaerobes with metronidazole was indicated. The 1-week treatment with metronidazole significantly reduced the proportions of these organisms for up to 6 months after treatment. Coincident with these findings was an improvement in the clinical parameters, especially in those sites that initially had greater than 5 mm pocket or attachment loss. These sites showed a 2 mm or more reduction in pocket depth and an almost 2 mm gain in apparent attachment that was evident 6 months after treatment. The results obtained were in only five patients. However, the magnitude of improvement suggests that antimicrobial therapy directed against anaerobic organisms may be a valuable adjunct to periodontal therapy.     

Prevalence of periodontitis and DMFT index in patients with Crohn's disease and ulcerative colitis

Aim: To compare the prevalence of periodontal disease and the decayed, missing and filled teeth (DMFT) index in patients with Crohn's disease (CD) and ulcerative colitis (UC) with those without these diseases. Material and Methods: Ninety‐nine CD (39.0 SD±12.9 years), 80 UC (43.3 SD±13.2) and 74 healthy controls (40.3 SD±12.9) were compared for DMFT index and presence of periodontitis. Probing pocket depth (PPD), clinical attachment loss (CAL), bleeding on probing (BOP), plaque and DMFT index were measured on all subjects. The presence of periodontitis was defined as having CAL 3 mm in at least four sites in different teeth. Results: Significantly more patients with UC (90.0%; p<0.001) and CD (81.8%; p=0.03) had periodontitis than controls (67.6%). Among smokers, UC patients had significantly more periodontitis. CD had a greater mean DMFT score (18.7 versus 13.9; p=0.031) compared with controls and UC had greater median PPD (2.2 versus 1.7 mm; p<0.0001) than controls. Among non‐smokers, CD (2.4 mm; p<0.0001) and UC showed deeper pockets (2.3 mm; p<0.0001) compared with controls (1.5 mm). UC had a greater mean DMFT score (15.3 versus 12.1; p=0.037) compared with controls. Conclusions: CD and UC patients had higher DMFT and prevalence of periodontitis than controls, but smoking was an effect modifier.     

Dental magnetic resonance imaging for periodontal indication – a new approach of imaging residual periodontal bone support

Objective: The standard imaging techniques used in dentistry consist of two-dimensional radiographic techniques like intraoral periapical (PA) radiographs, bitewings or extraoral panoramic X-rays. Three-dimensional methods, such as cone beam computed tomography (CBCT), are not standard procedures. In several fields of dentistry, such as oral surgery or implantology, dental magnetic resonance imaging (DMRI), a technique without radiation exposure, has already been introduced as a new promising diagnostic tool. The aim of this study was to compare the agreement of DMRI and PA radiographs in measuring residual periodontal bone support.

Material and methods: In this study, the residual periodontal bone support of 21 teeth was investigated and compared with DMRI and PA radiographs by two independent raters. Intra-class correlation coefficients (ICCs) were calculated using the software R to identify the intra-rater and inter-rater agreement of the two modalities. Bland–Altman plots were created to directly compare the two methods.

Results: Overall, all calculated ICC values showed an excellent intra-rater and inter-rater agreement (>0.9) for DMRI, as well as PA radiographs. Bland–Altman analysis also showed a strong agreement between both diagnostic methods in this study.

Conclusions: In conclusion, there was a strong agreement between DMRI and PA. Thus, DMRI proved to be a comparable method to PA radiographs for evaluating the proportion of residual periodontal bone support.     

根管充填质量对根管治疗术远期疗效的影响

目的：从X线影像角度分析根管充填质量对根管治疗远期疗效的影响。方法：选择已行根管治疗2a或2a以上的牙，运用平行投照法对根管治疗牙进行摄片；询问、查阅病史，了解患者年龄、性别、牙病病因及治疗时间；检查目前该牙根尖周状况；用SPSS13．0软件进行χ^2检验。结果：共调查病例215例，根管治疗牙376颗．成功率为54．79％。若以根管计算，共有513个根管，成功率为61．4％。根管充填质量（根充位置和密合度）对根管治疗疗效有显著的影响（P〈0．01），根充距离X线片根尖0．5．2mm时最理想；根充密合者成功率高，尤其是根尖部。性别、年龄和根管充填时间对根管治疗疗效无影响。结论：根管充填质量对根管治疗远期疗效有显著影响。     

The influence of periodontal status and serum biomarkers on salivary leptin levels in systemic lupus erythematosus patients

ObjectiveThis study aimed to investigate the influence of periodontal status, clinical data, and serum markers on salivary leptin levels in patients with systemic lupus erythematosus (SLE).MethodsA case–control study was conducted with 38 patients with SLE and 29 healthy controls. Periodontal data included periodontal probing depth (PPD), clinical attachment level (CAL), and gingival bleeding on probing (BOP). Stimulated saliva samples were collected to analyze salivary leptin levels. Clinical and serum data were collected from the SLE group. Statistical analysis included the t-test, Mann–Whitney test, Spearman correlation coefficient, and a structural equation model.ResultsThe SLE group had a lower salivary leptin level than the control group (P = 0.002). The model revealed that SLE had an inverse and independent effect on salivary leptin (standardized estimate =  ? 0.289, P = 0.023). Moreover, salivary leptin level negatively correlated with the serum levels of triglyceride, creatinine, and leukocytes, positively correlated with the serum total cholesterol, but was not significantly correlated with the periodontal status.ConclusionThese findings suggest that patients with SLE have a lower salivary leptin level. In addition, the level of salivary leptin does not appear to be related to periodontal status in patients with SLE.     

The mucosal attachment to titanium implants with different surface characteristics: an experimental study in dogs

BACKGROUND: Findings from in vitro studies have indicated that the orientation and proliferation of cells on titanium surfaces may be influenced by the topography of the surface on which they are grown. It may be argued, therefore, that differences may occur in the mucosal attachment to titanium implants with different surface roughness. AIM: The present experiment was performed to study the composition of the soft tissue barrier that formed to implants prepared with well-defined smooth or rough surfaces. MATERIAL AND METHODS: Five beagle dogs were used. Four implants made of c.p. titanium were placed in the right edentulous mandibular premolar region. After 3 months, two different types of abutments were connected: one experimental (OA) with a dual, thermal acid-etched surface ('Osseotite'), and one regular (RA) abutment with a 'turned' surface. At the end of a 6-month period during which proper plaque control had been maintained, biopsies including the implant and the surrounding soft and hard tissues were obtained, decalcified and processed for light and electron microscopy. A confocal He-Ne laser profilometer was used to study the surface topography of the abutments. RESULTS: The attachment between the peri-implant mucosa and titanium abutments with either a turned (RA; 'smooth') or acid-etched (OA; 'rough') surface was similar from both a quantitative and a qualitative aspect. The attachment comprised a barrier epithelium and a zone of connective tissue attachment of similar dimension at RA and OA. It was further observed that the 'inner' zone of the connective tissue attachment at both types of abutment was composed of about 30-33% fibroblasts and 63-66% collagen. CONCLUSION: It was demonstrated that the soft tissue attachment that formed to implants made of c.p. titanium was not influenced by the roughness of the titanium surface.