Bernd Röhrig

In vitro evaluation of various bioabsorbable and nonresorbable barrier membranes for guided tissue regeneration

BackgroundDifferent types of bioabsorbable and nonresorbable membranes have been widely used for guided tissue regeneration (GTR) with its ultimate goal of regenerating lost periodontal structures. The purpose of the present study was to evaluate the biological effects of various bioabsorbable and nonresorbable membranes in cultures of primary human gingival fibroblasts (HGF), periodontal ligament fibroblasts (PDLF) and human osteoblast-like (HOB) cells in vitro.MethodsThree commercially available collagen membranes [TutoDent® (TD), Resodont® (RD) and BioGide® (BG)] as well as three nonresorbable polytetrafluoroethylene (PTFE) membranes [ACE (AC), Cytoplast® (CT) and TefGen-FD® (TG)] were tested. Cells plated on culture dishes (CD) served as positive controls. The effect of the barrier membranes on HGF, PDLF as well as HOB cells was assessed by the Alamar Blue fluorometric proliferation assay after 1, 2.5, 4, 24 and 48 h time periods. The structural and morphological properties of the membranes were evaluated by scanning electron microscopy (SEM).ResultsThe results showed that of the six barriers tested, TD and RD demonstrated the highest rate of HGF proliferation at both earlier (1 h) and later (48 h) time periods (P < 0.001) compared to all other tested barriers and CD. Similarly, TD, RD and BG had significantly higher numbers of cells at all time periods when compared with the positive control in PDLF culture (P ≤ 0.001). In HOB cell culture, the highest rate of cell proliferation was also calculated for TD at all time periods (P < 0.001). SEM observations demonstrated a microporous structure of all collagen membranes, with a compact top surface and a porous bottom surface, whereas the nonresorbable PTFE membranes demonstrated a homogenous structure with a symmetric dense skin layer.ConclusionResults from the present study suggested that GTR membrane materials, per se, may influence cell proliferation in the process of periodontal tissue/bone regeneration. Among the six membranes examined, the bioabsorbable membranes demonstrated to be more suitable to stimulate cellular proliferation compared to nonresorbable PTFE membranes.

Depression and functional impairment independently contribute to decreased quality of life in cancer patients prior to chemotherapy

Background. An inverse association either between depression or impaired functional status and quality of life (QoL) has been reported for cancer patients, but the independent effect of depression or depressive symptoms and of functional impairment on QoL is unclear. Patients and methods. We investigated the prevalence of depression or depressive symptoms with the Beck Depression Inventory (BDI), the functional impairment with the ECOG-Performance-Status (ECOG-PS) and the QoL with the EORTC-QLQ-C30 questionnaire in a sample of 175 hospitalised cancer patients prior to the start of chemotherapy. Results. Sixteen of 175 patients (9.1%) screened positive for major depression, 29 (16.6%) had mild to moderate depressive symptoms. In 11 of 15 scales of the EORTC-QLQ-C30 questionnaire depression or depressive symptoms were significantly associated with worse QoL in univariate analysis and in 12 of 15 scales poor ECOG-PS was significantly associated with worse QoL. In multivariate analysis including ECOG-PS and BDI, the effect of depression and/or depressive symptoms on QoL was persistent in seven scales: global QoL, physical- and role functioning, fatigue, nausea & vomiting, pain, and constipation, that of ECOG-PS in five scales: global QoL, emotional functioning, nausea & vomiting, pain, and appetite loss. Conclusions. Signs of major depression or depressive symptoms and impaired functional status contribute independently to poorer QoL in cancer patients prior to chemotherapy.

Health‐related quality of life in elderly cancer patients, elderly non‐cancer patients and an elderly general population

Health-related quality of life (QoL) is a major topic within the care for cancer patients (CP). Compared with the general population (GP), QoL of CP is worse in most dimensions; however, only few data comparing QoL of CP with that of other patients have been provided so far. We determined QoL with the European Organization for Research and Treatment of Cancer QLQ-C30 questionnaire in hospitalized patients aged 60 years and older: 195 CP and 130 patients treated for other medical disorders (MP). In addition, data were compared with an age- and gender-stratified German GP. Explorative statistical analyses were performed. The CP aged >or=70 years compared with those aged 60-69 years had decreased QoL in two scales, physical and cognitive functioning, MP in four scales, physical and role functioning, fatigue and dyspnoea respectively. Compared with the GP, both CP and MP had worse QoL in almost all scales. The CP and MP differed in two of 15 scales only, with CP having lower scores in emotional functioning and more loss of appetite. In conclusion, reduced QoL in elderly CP compared with GP cannot solely be attributed to the diagnosis of cancer, but also to a medical disorder requiring inpatient hospital care.

Induction of tolerogenic lung CD4+ T cells by local treatment with a pSTAT-3 and pSTAT-5 inhibitor ameliorated experimental allergic asthma

Signal transducer and activator of transcription (STAT)-3 inhibitors play an important role in regulating immune responses. Galiellalactone (GL) is a fungal secondary metabolite known to interfere with the binding of phosphorylated signal transducer and activator of transcription (pSTAT)-3 as well of pSTAT-6 dimers to their target DNA in vitro. Intra nasal delivery of 50 μg GL into the lung of naive Balb/c mice induced FoxP3 expression locally and IL-10 production and IL-12p40 in RNA expression in the airways in vivo. In a murine model of allergic asthma, GL significantly suppressed the cardinal features of asthma, such as airway hyperresponsiveness, eosinophilia and mucus production, after sensitization and subsequent challenge with ovalbumin (OVA). These changes resulted in induction of IL-12p70 and IL-10 production by lung CD11c(+) dendritic cells (DCs) accompanied by an increase of IL-3 receptor α chain and indoleamine-2,3-dioxygenase expression in these cells. Furthermore, GL inhibited IL-4 production in T-bet-deficient CD4(+) T cells and down-regulated the suppressor of cytokine signaling-3 (SOCS-3), also in the absence of STAT-3 in T cells, in the lung in a murine model of asthma. In addition, we found reduced amounts of pSTAT-5 in the lung of GL-treated mice that correlated with decreased release of IL-2 by lung OVA-specific CD4(+) T cells after treatment with GL in vitro also in the absence of T-bet. Thus, GL treatment in vivo and in vitro emerges as a novel therapeutic approach for allergic asthma by modulating lung DC phenotype and function resulting in a protective response via CD4(+)FoxP3(+) regulatory T cells locally.

Radiographic investigation of frequency and location of root canal curvatures in human mandibular anterior incisors in vitro.

The aim of the present in vitro study was to evaluate the degree and location of root canal curvatures of mandibular anterior incisors. A total of 396 extracted human permanent anterior incisors (248 central and 148 lateral) were included in this investigation. Exclusion criteria were teeth with extensive carious lesions, restorations, and root canal treatment. The specimens were fixed in a special device and digitally x-rayed (Heliodent MD; Sirona, Benzheim, Germany; Merlin 2.1, Olympus/PerkinElmer, Waltham, MA) with the parallel technique. The distances from the cementoenamel junction (CEJ) to the first curvatures as well as the according angles were recorded. The results were analyzed descriptively, and p values were calculated with the Wilcoxon test. The mean distance between the CEJ and the first curvature of the central anterior incisors was 13.8 mm (standard deviation +/- 2.6) and that of the lateral anterior incisors was 12.3 (standard deviation +/- 2.5), respectively. A total of 82 (33.1%) central and a total of 118 (79.7%) lateral anterior incisors exhibited curvatures. No statistically significant differences between left and right anterior incisors could be observed regarding the canal curvature locations (p < 0.001) and the angle values (p < 0.04). The results showed a high percentage of mandibular anterior incisors with a mean curvature located 13 mm apically from the CEJ. The findings of this study may enhance the predictability of endodontic treatment and minimize errors during post insertion.

The combination of diffractive and refractive multifocal intraocular lenses to provide full visual function after cataract surgery

Purpose. To investigate if implantation of a far dominant refractive multifocal intraocular lens (IOL) in one eye and a near dominant diffractive multifocal IOL in the fellow eye improves range of vision following cataract surgery. Methods. This was a prospective, nonrandomized, case-control study involving 20 patients (40 eyes) scheduled for cataract surgery. Inclusion criteria were bilateral cataracts, minimum age 50 years, availability for follow-up visits, and informed consent. All patients received a far dominant refractive multifocal IOL (ReZoom, Abbott Medical Optics) in their dominant eye and a near dominant diffractive multifocal IOL (Tecnis ZM900, AMO) in their nondominant eye. Preoperative and postoperative measurements (3 months) included refraction, uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), reading acuity, and reading speed. Results. All patients completed the study. We present results of the 3-month postoperative visit. The patient group comprised 14 females and 6 males, with mean age 72 years (SD 6.1 years). Postoperatively, the mean sphere was 0.05 ± 0.31 D and the cylinder −0.31 ± 0.37 D. At the 3-month visit, mean binocular distance UCVA was 0.080 logMAR (SD 0.070) and BCVA was 0.030 logMAR (SD 0.066). The mean binocular near visual acuity was 0.140 logMAR (SD 0.068), mean binocular best-corrected, near visual acuity 0.060 logMAR (SD 0.060). Conclusions. The combination of a far dominant refractive multifocal IOL (with better distance performance) with a near dominant diffractive multifocal IOL (with better near vision) proved to be very suitable to help meet cataract patients’ visual needs.

The effectiveness of a novel optical probe in subgingival calculus detection

OBJECTIVES The aim of the present study was to evaluate the effectiveness of a novel optical calculus detection system under in vivo conditions. METHODS One hundred and seventy-six tooth surfaces from 44 adult teeth that were indicated for extraction were selected for the present study. The patients were randomly assigned to one of the two experimental groups. In group A (n = 96), clinical presence or absence of subgingival calculus deposits was determined using the light-emitting diode-based optical probe (OP). In group B (n = 80), the subgingival deposits were first recorded with the OP followed by root surface debridement until no subgingival deposits could be detected by the device. Teeth were then extracted and examined under a stereomicroscope by two trained dentists (DENT 1, DENT 2) and a dental student. Results were compared with the measurements of the OP and direct visual control. RESULTS In group A, post-extraction results revealed 89% and 90% agreement with the positive and negative OPs detection. In group B, 17% of the surfaces demonstrated even after subgingival debridement and control with the detecting device still calcified deposits in the microscopic evaluation. The highest inter-examiner agreements were observed between DENT 1 and DENT 2. CONCLUSION It was shown that the optical detection system identifies subgingival calculus with a high efficacy and therefore, may be a support for the operator to determine the endpoint of root surface instrumentation.

The determination of the initial straight length in root canals of mandibular premolars -an in vitro study

The aim of the present roentgenographic in vitro study was to determine the initial straight length from the cemento-enamel junction (CEJ) to the appearance of a root canal curvature in human mandibular premolars. A total number of 282 mandibular premolars were examined. Exclusion criteria comprised root caries, extensive restorations and endodontically treated teeth. The teeth were fixed and digitally radiographed by means of a specially developed fixation device with standardized and reproducible distances with the parallel technique (Heliodent MD; Merlin 2.1). The distances from the CEJ to the first curvature (> 5°) (distance I), from the first curvature to a second curvature (distance II), and from the first or second curvature to the radiological apex (distance III) were recorded. The lengths of the initial straight distance and the appearance of a curvature were statistically analyzed and related to each other. In first mandibular premolars, the mean value for distance I was 10.9 mm, for distance II 3.7 mm and for distance III 3.04 mm. The mean values for the second mandibular premolars were 1.1 mm in distance I, 4.3 mm in distance II and 3.1 mm in distance III. No statistically significant differences between left and right mandibular premolars could be observed regarding the canal curvature location and the angle values. The results of this investigation show that curvatures are increasingly observed 9 to 12 mm from the original path in mandibular premolars.