Peter Eickholz

Digital Radiography of Interproximal Caries: Effect of Different Filters

The aim of this study was to compare the effect of different image processing modes (filters) on reproducibility and validity of the assessment of interproximal carious lesions on digitized radiographic images. Standardized radiographs of 34 extracted teeth exhibiting interproximal caries were obtained. All radiographs were digitized and using the FRIACOM–software the central depth (CD) of each carious lesion was measured on the unchanged radiographic image and after use of five different filters with 7fold and 18fold magnification. All measurements were repeated after 1 week to estimate reproducibility. Histometric CD assessments provided a gold standard for comparison with the radiographic measurements (validity). Neither reproducibility nor validity of CD measurements were improved by one of the filters. Measurements of dentinal lesions showed a statistically higher variability than those of enamel lesions (p<0.001). 18fold magnification provided more valid CD measurements than 7fold magnification (p<0.001). In this study digital manipulations of radiographic images failed to result in statistically significantly improved reproducibility or validity of CD measurements.

Serotypes of Aggregatibacter actinomycetemcomitans in Patients With Different Ethnic Backgrounds

BACKGROUND The identification of Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans) serotypes may add some important information to the understanding of the pathogenetic background of severe periodontal infections. This study compared serotypes of A. actinomycetemcomitans in two groups of periodontal patients with different ethnic backgrounds. METHODS A total of 194 patients (96 Germans and 98 Koreans) with aggressive or severe chronic periodontitis participated in the study. Microbiologic analysis of pooled samples from subgingival plaque was performed by using a real-time polymerase chain reaction (PCR) test for A. actinomycetemcomitans. In patients who tested positive for A. actinomycetemcomitans, serotypes (a through f) were determined by nucleic acid-based methods. RESULTS The prevalence of patients who tested positive for A. actinomycetemcomitans with the real-time PCR was comparable in both groups (Germans: 27.0%; Koreans: 22.2%). In German patients, the serotypes detected most frequently were b (33.3%), c (25.0%), and a (20.8%), whereas in Korean patients, the serotype distribution was different, with serotypes c (61.9%) and d (19.0%) accounting for >80% of the complete serotype spectrum. CONCLUSION Even if the percentage of patients who tested positive for A. actinomycetemcomitans was identical in patients with generalized aggressive and severe chronic periodontitis and different ethnic backgrounds, the distribution of A. actinomycetemcomitans serotypes may exhibit marked differences.

Guided tissue regeneration with bioabsorbable barriers. II. Long-term results in infrabony defects.

BACKGROUND The aim of this 5-year randomized controlled clinical trial was to evaluate the long-term results after guided tissue regeneration (GTR) therapy of infrabony defects using two bioabsorbable barriers. METHODS Fifteen pairs of contralateral infrabony defects in 15 patients with moderate to severe periodontitis were treated. Each patient received one polydioxanon (test: T) and one polylactide acetyltributyl citrate (control: C) barrier by random assignment. At baseline, 12, and 60 +/- 3 months after surgery clinical parameters and standardized radiographs were obtained. Vertical bone levels (PBL-V) were measured during surgery and 60 +/- 3 months later by transgingival bone sounding. RESULTS Thirteen patients were available for the 60-month examinations. Twelve and 60 +/- 3 months after GTR, statistically significant (P< or =0.001) vertical attachment (CAL-V) gain was found in both groups (T12: 3.5 +/- 1.5 mm; T60: 2.2 +/- 1.8 mm; C12: 4.0 +/- 0.9 mm; C60: 2.4 +/- 1.0 mm). However, from 12 to 60 months after therapy both groups experienced significant CAL-V loss (P<0.05): two defects in the test group and three in the control group had CAL-V loss >2 mm compared to the 12-month reexamination. Twelve and 60 +/- 3 months after surgery, statistically significant (P<0.05) radiographic bony fill was found in both groups (T12: 1.2 +/- 1.3 mm; T60: 1.5 +/- 2.2 mm; C12: 0.9 +/- 1.4 mm; C60: 1.0 +/- 1.6 mm). Further, 60 months after surgery significant (P<0.05) PBL-V gain was found in both groups (test: 1.8 +/- 2.3 mm; control: 2.2 +/- 1.8 mm). The study failed to show statistically significant differences between test and control regarding CAL-V and PBL-V gain 60 months after surgery. CONCLUSION CAL-V gain achieved after GTR therapy in infrabony defects using both bioabsorbable barriers was stable after 5 years in 21 of 26 defects (81%).

Elevated gene expression of MMP-1, MMP-10, and TIMP-1 reveal changes of molecules involved in turn-over of extracellular matrix in cyclosporine-induced gingival overgrowth.

In humans, pathogenesis in cyclosporine A (CsA)-induced gingival overgrowth (GO) includes the accumulation of extracellular matrix (ECM) constituents, viz., collagen type-1 and type-3 and proteoglycans, in subgingival connective tissue. However, whether this increase is associated with alterations of molecules pivotal for the turn-over of collagens and proteoglycans remains unclear. The present study explores the status of matrix metalloproteinase MMP-1 and MMP-10, which are important for fibrillar collagen and proteoglycan turn-over, and their tissue inhibitor TIMP-1, on their gene expression and protein levels in frozen sections derived from GO and matched normal tissue. In situ hybridization (ISH) revealed elevated levels of MMP-1 gene expression in the connective tissue of GO compared with normal tissue. This elevation also applied to MMP-10 and TIMP-1, the latter exhibiting the strongest gene transcription in the deep connective tissue. These differences detected by ISH were corroborated by quantitative reverse transcription/polymerase chain reaction; relative gene expression analysis indicated a 1.9-fold increase for MMP-1, a 2.3-fold increase for MMP-10, and a 4.8-fold increase for TIMP-1. Detection of the protein by indirect immunofluorescence showed that normal gingival tissue was devoid of all three proteins, although they were detectable in GO tissue, with emphasis on TIMP-1. Analysis of our data indicates elevated levels of MMP-1 and-10, and particularly TIMP-1. With respect to TIMP-1, this elevation may in turn lead to alterations in ECM turn-over by abrogating MMP-1 and MMP-10, thereby contributing to ECM accumulation associated with GO.

Digital enhancement of radiographs for assessment of interproximal dental caries

OBJECTIVES Evaluation of a particular digital caries image-enhancing mode (filter) for its effect on the validity of measurements of caries lesion depth. METHODS Standardized radiographs of 44 extracted teeth exhibiting interproximal caries lesions were obtained. Six radiographs were obtained of each tooth and digitized. Four radiographs were made using D-speed film with and without soft tissue scattering equivalent (STSE) at normal exposure time (0.32 s) and underexposed (0.16 s). Two were made using E-speed film with STSE normally (0.16 s) and underexposed (0.08 s). On each of the 264 radiographs, 4 independent examiners measured the central depth (CD) of 1 carious lesion per tooth both on the unchanged radiographic image and after use of the filter. Histometric CD assessments provided a gold standard for comparison with the radiographic measurements (validity). Repeated measures ANOVA was calculated for validity in relation to examiner, lesion type, filter, film type, exposure time and STSE. RESULTS The lesion type was identified to statistically significantly influence the validity of CD measurements. Examiner in combination with defect type (P<0.001), filter (P = 0.017), exposure (P = 0.027) and film type (P = 0.044) had an additional albeit small effect. CONCLUSIONS The lesion type significantly influenced the validity of CD measurements: enamel lesions were less underestimated than dentin lesions.

Comprehensive Treatment of Periodontitis in Patients With von Willebrand Disease

BACKGROUND Hemophilia A and B and von Willebrand disease (VWD) belong to the most frequent congenital coagulation disorders and are a significant problem in patients who require periodontal therapy or tooth extraction. These patients need specialist management because even minor invasive procedures can precipitate a prolonged bleeding episode. However, although dental care presents major challenges in these patients, only a few studies are available. METHODS In this case series, the comprehensive periodontal treatment of four patients with hemorrhagic disorders (VWD type I and mild hemophilia B) is described. There was a close collaboration between the periodontist and the hematologist: all patients were scheduled for premedication with desmopressin and other pharmaceuticals at the hematologists office. After one session of scaling and root planing was performed in all patients, local agents such as tranexamic acid were used. In the course of periodontal therapy, access-flap surgery was performed in one of the four patients. RESULTS Before treatment, the rates of probing depths (PDs) of 4 to 6 mm (20% to 57%) or ≥ 7 mm (2% to 20%) were high. Three months after treatment, the rates of PDs of 4 to 6 mm (5% to 42%) or ≥ 7 mm (0% to 2%) decreased significantly in all patients. Attachment gains were also observed. A secondary hemorrhage did not occur in any of the patients, and wound healing proceeded without any complications. CONCLUSION Effective periodontal treatment can be provided to patients with hemorrhagic disorders with the combined efforts of the periodontist and hematologist.

Evaluation of two siblings with Papillon-Lefèvre syndrome 5 years after treatment of periodontitis in primary and mixed dentition.

BACKGROUND This case report describes the clinical and microbiologic long-term outcome 5 years after periodontal therapy of two siblings diagnosed with Papillon-Lefèvre syndrome (PLS) and tinea capitis. METHODS In 2005, two brothers diagnosed with PLS and tinea capitis began periodontal treatment. Both of them showed premature mobility of the primary dentition, markedly increased probing depths, and subgingival Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans; Aa). Initial therapy consisted of scaling and root planing based on the concept of full-mouth disinfection, extraction of periodontally hopeless deciduous teeth, and systemic antibiotics. Reevaluation of clinical parameters revealed a dramatic improvement. After that, the patients were enrolled in a stringent maintenance program. Microbiologic monitoring was performed 1 and 5 years after treatment. RESULTS Five years after initial treatment, the periodontal situation was stable in both patients. Residual deciduous teeth, with the exception of one tooth, could be retained and no further teeth were lost. Further disease progression on the previously involved teeth was controlled, and development of periodontitis on erupting teeth was prevented for a period of 5 years. CONCLUSIONS Even periodontally affected deciduous teeth can be treated successfully in patients with PLS. Suppression of Aa and a stringent maintenance program are of high importance.

Enamel Matrix Derivative in Propylene Glycol Alginate for Treatment of Infrabony Defects With or Without Systemic Doxycycline: 12- and 24-Month Results

BACKGROUND This aim of this study is to compare regenerative therapy of infrabony defects with and without administration of post-surgical systemic doxycycline (DOXY) 12 and 24 months after therapy. METHODS In each of 57 patients, one infrabony defect (depth ≥ 4 mm) was treated regeneratively using enamel matrix derivative at two centers (Frankfurt am Main and Heidelberg). By random assignment, patients received either 200 mg DOXY per day or placebo (PLAC) for 7 days after surgery. Twelve and 24 months after surgery, clinical parameters (probing depths [PDs] and vertical clinical attachment level [CAL-V]) and standardized radiographs were obtained. Missing data were managed according to the last observation carried forward. RESULTS Data of 57 patients (DOXY: 28; PLAC: 29) were analyzed (26 males and 31 females; mean age: 52 ± 10.2 years; 13 smokers). In both groups, significant (P <0.01) PD reduction (DOXY: 3.7 ± 2.2 mm; PLAC: 3.4 ± 1.7 mm), CAL-V gain (DOXY: 2.7 ± 1.9 mm; PLAC: 3.0 ± 1.9 mm), and bone fill (DOXY: 1.6 ± 2.7 mm; PLAC: 1.8 ± 3.0 mm) were observed 24 months after surgery. However, the differences between both groups failed to be statistically significant (PD: P = 0.574; CAL-V: P = 0.696; bone fill: P = 0.318). CONCLUSIONS Systemic DOXY, 200 mg/day for 7 days, after regenerative therapy of infrabony defects did not result in better PD reduction, CAL-V gain, or radiographic bone fill compared with PLAC 12 and 24 months after surgery, which may be attributable to low power and, thus, random chance.

Reproducibility of a commercially available subgingival plaque sampling strategy and analysis strategy with oligonucleotide probes.

Abstract Objectives: The aim was to evaluate the intra-test agreement of pooled samples from the deepest periodontal pocket of each quadrant with a commercially available test kit based on hybridization of 16S rRNA. Material and methods: Plaque samples of 50 patients with generalized severe chronic periodontitis before therapy were pooled in two separate vials in order to detect and compare counts of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola. Cohen’s κ and interclass correlation coefficients were calculated to judge intra-test agreement. Results: Cohen’s κ for detection and counts of Tannerella forsythia and Treponema denticola showed a perfect agreement. Porphyromonas ginigivalis was identified in both tests with a substantial agreement, whereas detection of Aggregatibacter actinomycetemcomitans varied in eight patients resulting in a good agreement. Possible confounding factors could not be identified statistically. Conclusion: Test results of the commercial 16S rRNA test are perfectly reproducible regarding detection of red complex pathogens. Intra-test agreement concerning detection of Aggregatibacter actinomycetemcomitans was less favorable. Clinical relevance: Detection of certain periodontal pathogens may alter the treatment and lead to prescription of antibiotics parallel to mechanical debridement. It is quite important not to use antibiotics excessively. Thus, the basis for decision-making in favor of antibiotics should be solid.

Is gingival bleeding a symptom of type 2 and 3 von Willebrand disease

Background Von Willebrand disease (VWD) is the most common inherent bleeding disorder. Gingival bleeding is a frequently reported symptom of VWD. However, gingival bleeding is also a leading symptom of plaque-induced gingivitis and untreated periodontal disease. In type 1 VWD gingival bleeding was not increased compared to controls. Thus, this study evaluated whether type 2 and 3 VWD determines an increased susceptibility to gingival bleeding in response to the oral biofilm. Methods Twenty-four cases and 24 controls matched for age, sex, periodontal diagnosis, number of teeth and smoking were examined hematologically (VWF antigen, VWF activity, factor VIII activity) and periodontally (Gingival Bleeding Index [GBI]), bleeding on probing [BOP], Plaque Control Record [PCR], periodontal inflamed surface area [PISA], vertical probing attachment level). Results BOP (VWD: 14.5±10.1%; controls: 12.3±5.3%; p = 0.542) and GBI (VWD: 10.5±9.9%; controls: 8.8±4.8%; p = 0.852) were similar for VWD and controls. Multiple regressions identified female sex, HbA1c, PCR and PISA to be associated with BOP. HbA1c and PCR were associated with GBI. Number of remaining teeth was negatively correlated with BOP and GBI. Conclusion Type 2 and 3 VWD are not associated with a more pronounced inflammatory response to the oral biofilm in terms of BOP and GBI.