International Poster Journal of Dentistry and Oral Medicine, 03/2016

Einleitung: Da die Angiogenese mit dem Prozess der Karzinogenese eng assoziiert ist, war es Ziel der Studie, histologisch quantifizierbare Angiogeneseparameter in Assoziation mit der Entartungstendenz, der Aggressivität und der Prognose oraler Plattenepithelkarzinome (oPEC) zu evaluieren. Materialien und Methoden: Es wurden (1) histologische Präparate von 49 Leukoplakien (Leu), 33 Leu mit leichten Dysplasien (Leu-SIN1), 13 Leu-SIN2 und 36 aus Leu entstandene oPEC auf Mikrogefäßzahlen (MVD), Gefäßdurchmesser und VEGF-Expression analysiert um den Einfluss der Angiogenese auf die Entartungstendenzen zu berechnen. Anschließend wurden (2) bei 50 oPEC die histologisch bestimmte MVD und die CD31-Färbeintensität mit dem Tumorstaging und der Prognose bei einer mittleren Nachbeobachtungszeit von 54 Monaten korreliert. Ergebnisse: (1) Es zeigten sich bei der MVD signifikante Unterschiede zwischen Leu und Leu-SIN2/oPEC (p0,05) sowie zwischen Leu-SIN1 und oPEC (p0,05). Bei oPEC waren die Gefäßdurchmesser signifikant gegenüber Leu erhöht (p0,05). Die VEGF-Expression stieg signifikant graduell von Leu-SIN1 zu oPEC an (p0,05). 2) Signifikant höhere Gefäßzahlen wurden bei T3/T4, N>0 und G3-4-oPEC gesehen (alle p0,05). Höhere MVD-Werte waren signifikant mit früheren Rezidiven und gehäuften Metastasen und einem verminderten Gesamtüberleben verknüpft (alle p0,05). Diskussion: Es konnte exemplarisch an der Leukoplakie als präkanzeröse Läsion der wichtige Stellenwert der Angiongenese bei der graduellen malignen Transformation nachgewiesen werden. Bei Manifestation eines oPEC beeinflusst die Angiogenese sowohl das lokale als auch das metastatische Tumorwachstum mit einer signifikanten Korrelation zu prognostischen Parametern wobei sich die MVD als aussagekräftigster Parameter darstellt. Schlagwörter: Leukoplakie, orales Plattenepithelkarzinom, Angiogenese

Background: Despite the use of fluorides, molars are still susceptible to dental caries, and hence additional preventive programs are essential. School-based pit and fissure sealant programs are one such public health initiative to prevent dental caries in molars. Aims and Objectives: 1. To investigate the effectiveness of school-based pit and fissure sealant programs in the prevention of dental caries in children. 2. To find out whether these programs are implementable in India. Methods: A systematic literature survey was carried out in October 2015 in electronic data bases such as PubMed, PubMed central and Google Scholar, with MeSH terms "PIT AND FISSURE SEALANTS" and key words such as "School based pit and fissure sealant programs". Articles in English published between January 2000 to October 2015 were selected. The outcome measure was the incidence of dental caries among sealed verses unsealed teeth. 31 articles were obtained through searches, of which 25 met the inclusion criteria and were selected for study. Results: The first permanent molars that received sealants had less risk of developing new caries at 1 year of follow-up. The total retention of the pit and fissure sealants (1 year) ranged from 50% to 92 %, and the reduction in caries incidence ranged from 36.2% to 82.4 %. Conclusion: School-based pit and fissure sealant programs result in a significant reduction of dental caries and may be economically viable as the cost benefit ratio is also high. Similar programs could be implemented in India if resources were available. Schlagwörter: pit and fissure sealant, dental caries, prevention

Background: Despite a significant decrease in smoking prevalence over the past ten years, cigarette smoking still represents the leading cause of preventable morbidity and mortality. Thus, countries around the world have increasingly adopted pictorial health warning labels (HWLs) for tobacco packages to warn consumers about the risks and make an informed decision. Objectives: 1. To assess perceptions and the impact of health warning labels regarding tobacco habits. 2. To look at the evidence for controlling and preventing tobacco habits. Search methodology: A systematic literature survey was carried out in electronic data bases like PubMed, Google scholar, etc, using "health warning labels and tobacco" and "pictorial warning and tobacco" as keywords looking for biomedical research from the past 5 years. Data collection and analysis: Three authors independently assessed all studies for inclusion criteria and for study quality (SS, MBC, AK). Results were not pooled due to the heterogeneity of the included studies. Main results: 293 articles were extracted, of which 13 articles met the inclusion criteria and were selected for the review. Outcome variables reported were credibility, relevance, warning salience, health risks of smoking and change in behaviour i.e. smoking status, motivational impact, association of HWLs with educational level, comparison between effectiveness of positive versus negative labels, misinterpretation of HWLs and country by time interaction effects for all label effectiveness. Author's conclusion: From the limited number of heterogeneous studie, there is weak evidence that pictorial health warning labels (HWLs) are effective in changing smoking behaviour. Schlagwörter: health warning labels, pictorial warning, tobacco

Background and objectives: Orthodontics in Nepal do not have a long history. The first specialised orthodontic service by a Nepalese orthodontist was started in1990. Gradually, the number of orthodontists has increased, and the range of services provided by them has also expanded. The aim of this study was to find out the state of orthodontics in Nepal. Materials and Methods: The prevalence of malocclusion was assessed from past studies. Information regarding Nepalese orthodontists was obtained from the Nepal Medical Council, the Orthodontic and Dentofacial Orthopedic Association of Nepal and through personal contacts. Information of Nepalese living standard was obtained from the World Bank report. Results: Malocclusion is one of the most common dental problems, with high prevalence ranging from 73% to 90.4% at various places in Nepal. More than 50% of those with malocclusion have an extreme or severe need of orthodontic treatment. With only a few orthodontists (74), mostly centered in the capital and major cities, even people with severe and extreme treatment needs are deprived of orthodontic treatment. The minimum cost for orthodontic treatment even in a government hospital is approximately one third of the per capita income of the Nepalese people ($220 minimum cost vs $698.30 per capita income a/c to the World Bank 2014) Conclusion: Although orthodontic services are urgently required, people are unable to afford them due to low socioeconomic status. Also, most of the orthodontists are concentrated in the major cities, with difficult access for people residing in rural areas. Schlagwörter: Orthodontics, malocclusion, per capita income

This retrospective study describes the craniofacial architecture of post-pubertal patients with cleft lip and palate by using DELAIRE whole skull analysis along with the analysis by SEGNER AND HASUND. 177 cephalometric X-ray films from a group of patients (114 male, 63 female) of the former Wolfgang Rosenthal Clinic Thallwitz, Germany, were analyzed. Typical changes in the viscerocranium (mandibular and maxillary retrognathia in a vertical basal open relationship) were accompanied by small yet statistically significant changes to the neurocranium. The study revealed midface deficits in the sagittal plane and a reduced height of the midface in favour of the lower face. Furthermore, a reduced craniofacial base line and cranial height and a reduced angle between the cranial base and craniofacial base line were evident. The angle between the cranial base and the basilar slope was enlarged, suggesting an abnormal posture of the cervical spine in CLP patients. Cleft lip and palate along with late-closure corrective surgery may cause complex effects on the entire craniofacial architecture, including, but not limited to, the facial region. Whole skull analyses - such as the DELAIRE analysis - are beneficial in assessing abnormal dimensions extending beyond the face and oral cavity to the entire viscerocranium and neurocranium in general, as might commonly occur in cleft lip and palate patients. Schlagwörter: Cleft, delaire analysis, segner hasund analysis, whole skull analysis, craniofacial architecture, thallwitz

Einleitung: Für die transversale Erweiterung des Oberkiefers können dental, skelettal oder kombiniert dental-skelettal verankerte Apparaturen zum Einsatz kommen. Der Vorteil von knochenverankerten Apparaturen ist die Kraftübertragung direkt am Knochen, was zu einer Reduktion der bei der zahngetragenen Apparaturen auftretenden Nebenwirkungen, wie Zahnkippungen, Wurzelresorptionen und Dehiszenzen der bukkalen Knochenlamelle, führt. Konfektionierte knochenverankerte Distraktoren sind meist submukös am Knochen fixiert. Dabei ist jedoch das Vorgehen invasiver sowie erfahrungsgemäß auch der Patientenkomfort reduziert und die Durchführung der Aktivierung erschwert. Material und Methode: Ein neu entwickelter patientenspezifischer Distraktor wurde durch Kombination einer Standard-Hyraxschraube aus Titan und winkelstabilen Osteosyntheseplatten entwickelt. Nach individueller Positionierung und Fixierung der Standard-Titan-Lockingplatten und der Titan-Hyraxschraube am Patientenmodell werden diese Komponenten laserverschweißt. Die intraoperative Fixierung der Apparatur erfolgt transmukosal mit Standard-Locking-Minischrauben. Ergebnisse: Unsere klinischen Erfahrungen bei 5 Patienten zeigten durchweg einen erfolgreichen Therapieverlauf. Die Aktivierung durch die Patienten konnte verlässlich und in gleicher gewohnter Weise erfolgen wie bei herausnehmbaren Apparaturen oder dental verankerten Gaumennahterweiterungsapparaturen. Auch die Entfernung der patientenspezifischen Distraktoren war im Vergleich zu submukös fixierten Apparaturen deutlich non-invasiver und einfacher, da lediglich die Verankerungsschrauben lediglich gelöst werden müssen. Schlussfolgerung: Die beschriebene neuartige Methode kombiniert die Vorteile der Hyrax-Apparatur bezüglich Patientenkomfort und Behandlerbedienung mit den therapeutischen Vorteilen eines skelettal verankerten Distraktors. Die einfachere Fixierung, Handhabung und Entfernung dieser Apparatur spricht für einen Einsatz im Routinenbetrieb. Schlagwörter: Gaumennahterweiterung, Distraktionsosteogenese

Ziel: Integration von biostatistischen Inhalten in den Kurs der kieferorthopädischen Behandlung I (9. Semester) durch praktische Übungen durch die Studierenden. Material und Methode: Zum Inhalt des Kurses gehört die Vermessung und Auswertung der eigenen Gebissmodelle durch die Studierenden. Die Modelle wurden dreidimensional (ZirkonZahn AR600) gescannt und die Kursteilnehmer hatten die Möglichkeit unter Anleitung eines Tutors die virtuellen Modelle am Computer zu vermessen (Onyx Ceph® 3, ImageInstruments GmbH, Chemnitz). Folgend wurden in einer Vorlesung (60 min) ausgewählte Grundlagen der Statistik vermittelt. Im Anschluss wurde interaktiv mit den Kursteilnehmern eine Auswertung der von Ihnen selbst gewonnen Daten (R Project for Statistical Computing 3.1.0) in Bezugnahme auf die Inhalte der Vorlesung durchgeführt. Von den 37 Teilnehmern wurde ein Fragebogen mit 10 Fragen bezüglich der Vorkenntnisse, persönlichen Einstellung und Wichtigkeit von Kenntnissen in der Biostatistik für eine Promotion und für die spätere klinische Tätigkeit vor und nach der Veranstaltung ausgefüllt (5 Punkte Skala, "stimme nicht zu" bis "stimme voll zu"). Insgesamt konnten 68 Fragebögen ausgewertet werden. Der Vergleich vor/nach der Veranstaltung erfolgte mit einem Kruskal-Wallis-Rangsummentest. Ergebnisse: Die Vorkenntnisse werden von den Studierenden sehr heterogen eingeschätzt, einige geben ausreichende Grundkenntnisse (61%) an, 25% hingegen geben an keinerlei Kenntnisse von Statistik zu haben. Demgegenüber sind 91% der Studierenden überzeugt, dass für eine Promotion Statistik sehr wichtig sei. Eine stärkere Einbindung der Statistik in das Zahnmedizinstudium wurde eher ablehnend beurteilt, die Zustimmung erhöhte sich aber nach der Veranstaltung. Im Vergleich Vorher/Nachher zeigten sich bis auf eine Frage keine signifikanten Unterschiede: eine Vertiefung der statistischen Kenntnisse wurde nach dem Kurs von signifikant (p=0,04) weniger (!) Studierenden gewünscht als vorher. Schlussfolgerung: Die Vorkenntnisse der Studierenden sind sehr uneinheitlich. Ein ein-Tages-Kurs zur Medizinischen Statistik kann nur fragmentarisch Wissen vermitteln, aber die Bedeutung für die spätere zahnärztliche Tätigkeit verdeutlichen. Der Wunsch nach Vertiefung der Inhalte besteht allerdings kaum und konnte auch durch das Seminar nicht gesteigert werden. Schlagwörter: biostatischen Grundlagen, Kieferorthopädie, Studenten, Ein-Tages-Kurs

Purpose: The aim of this split-mouth study was to evaluate the behaviour of soft and hard tissue around implants with two different surface treatments. Materials and methods: 10 patients (5 men, 5 women) were treated with fixed partial dentures supported by implants. Each patient received at least 2 implants (1 control, 1 test) into an edentulous quadrant. The control implants (Osseotite, OSS) had a dual acid-etched (DAE) surface in the apical portion and a machined coronal part; test implants (Full Osseotite, FOSS) had a completely DAE surface. Machined healing abutments were placed on control implants and DAE abutments on test ones. After 3 months from surgery, a mini-invasive sample of soft tissue was collected from the first 7 patients recruited for the study (4 women and 3 men). The samples were analysed by microRNA (miRNA) microarray. Standardised periapical radiographs were taken to investigate interproximal bone levels at baseline (immediately after implant insertion), 2 months, 6 months, and 1 year post-implant placement. Plaque index (PI), bleeding on probing (BOP) and periodontal depth (PD) were recorded at 3 and 6 weeks, and at 2, 3, 6 and 12 months post-implant placement. Differences in bone resorption over time were evaluated with the Friedman test followed by post-hoc Wilcoxon signed ranks tests. Differences in bone resorption, PI, BOP and PD between the two types of implant over time were assessed by the repeated measures ANOVA test for ranked data. A p ≤0.05 was considered statistically significant. Statistical analyses were carried out with SPSS v.20. Microarray data were processed by GeneSpring® software and their overall variability was examined by box-plot analysis, scatter-plot analysis, hierarchical cluster analysis (HC) and principal component analysis (PCA). Individual miRNAs modulated by the experimental treatments were identified by volcano-plot (thresholds 2-fold and P0.05), support vector machine and k-nearest neighbour analyses. The results of miRNA microarray were compared with measured clinical parameters. Results: Control implants showed greater bone resorption compared to test ones; however, the difference was not statistically significant. Greater plaque accumulation was found for test surfaces, but the difference was not statistically significant. No statistically significant differences in BOP and PD were found. miRNA microarray analysis led to the following findings: - Implant sites with low plaque accumulation and absence of BOP had a gene expression profile similar to those with plaque deposits and an absence of BOP; sites with both high PI and high BOP had a completely different profile. - Implant sites with BOP present presented similar gene expression profiles independently from the type of implant surface. - Implant sites with high PI and normal bone resorption had a different expression profile from the other experimental conditions. - Implant sites with normal bone resorption despite high BOP differed from the other experimental conditions. This gene expression profile resembled that of FOSS implants. - Implant surface affected bone resorption: groups having similar bone resorption characteristics (normal vs. increased) clustered differently according to the implant type. Conclusions: DAE surfaces showed more plaque accumulation than machined ones; however, this did not affect the health of soft peri-implant tissue. In fact, BOP values did not differ between test and control implants. Furthermore, DAE surfaces induced lower bone resorption compared with machined ones. miRNA analysis suggested that soft tissue inflammation is more related to a specific host characteristic (gene expression profile) rather than to the presence of plaque or to a given implant surface. Some specific miRNA profile might be able to protect implant sites from bleeding and bone resorption irrespective of plaque accumulation. Possible future applications of the present findings include the use of the identified biomarkers for diagnosis and as drugs or coatings for implant surfaces in order to improve the health of peri-implant tissues. Schlagwörter: dental implants, peri-implant tissue, microRNA, titanium surfaces

Introduction: Through food and drink, various acids reach the oral cavity. In biofilms, lactic acid is produced, and gastric acid secretion leads to an extremely strong lowering of the pH. These changes in pH can influence corrosion processes in the oral cavity. The aim of this study was to simulate such pH conditions and to compare the electrochemical corrosion behaviour of 2 experimental CoCr alloys with same pitting resistance equivalent (PRE) value in 0.9% saline solution (pH 6.3) which was additionally adjusted with 2 different acids (0.02 M HCl and lactic acid) to the pH-values of 5, 4, 3 and 2. Material & Methods: The experimental dental alloys Co-28Cr-5Mo-1.5Si-Mn and Co-28Cr-10W-1.5Si-Mn with PRE=44.5 were used. From each alloy, 6 specimens were prepared. 0.9% saline solution was used as a reference electrolyte. With the use of a pH-meter (691, Metrohm), the pH-values of the saline solution were adjusted to pH 2, 3, 4 and5 either with 0.02 M HCl or lactic acid. With each alloy and electrolyte, electrochemical corrosion measurements according to ISO 10271 were performed, which consist of an open-circuit-potential measurement over 2 h followed by anodic polarisation (-150 mV~Ecorr to 1 V, speed 1 mV/sec). From each measurement, the parameters Ecorr after 2 h, Ez, Ep, ip, i(300 mV), i(300mV+Ez), icorr, Rp, E(-6) and E(-5) were determined. Results: Generally, the corrosion behaviour was different for both alloys and the acids used. With the exception of the calculated parameter Rp, higher corrosion resistance could be determined with decreasing pH in a clear ranking for Co-28Cr-5Mo-1.5Si-Mn with 0.02 M HCl; however, in lactic acid only to pH 3. For Co-28Cr-10W-1.5Si-Mn, decreasing corrosion could be measured in both acids only to pH 3; a clear ranking was found only for the calculated potential parameters. The most prominent differences could be seen at pH 2 adjusted with lactic acid: The icorr value was 71 ± 25 in lactic acid and 24 ± 5 nA/cm² in 0.02M HCl for Co-28Cr-5Mo-1.5Si-Mn, and respectively 2556 ± 1698 and 55 ± 28 nA/cm² for Co-28Cr-10W-1.5Si-Mn. Conclusion: The Mo-containing alloy showed good acidic corrosion resistance for all pH values used which were adjusted with 0.02 M HCl. This alloy is superior at a low pH-value adjusted with lactic acid compared to Co-28Cr-10W-1.5Si-Mn. Acknowledgement: Special thanks to Dentaurum (Ispringen, Germany) for casting the specimens. Schlagwörter: electrochemical corrosion measurements, experimental nonprecious alloys, pitting resistance equivalent (PRE), organic and anorganic acids

Background: One of the problems encountered with the immediate implant placement is insufficient soft tissue that could achieve a tension-free primary closure. In this case report, a simple approach was recently performed to provide sufficient primary closure at the time of immediate implant placement. Patient and intervention: A 38-year-old non-smoking medically fit female patient presented to the Prosthodontics Department, Faculty of Dentistry - Cairo University with a history of endodontic treatment in the maxillary left lateral incisor and repeated post fracture. The condition resulted in insufficient tooth structure to support a post core restoration. Hence, it was decided to replace the tooth with an endosseous implant. Oral examination revealed that the remaining supra-gingival portion of the broken lateral incisor could hinder adequate primary closure at the time of immediate implant placement. Therefore, it was decided to reduce the root to 2mm below gingiva and leave it for 3 weeks to allow for growth of soft tissue in the exposed area, thereby providing adequate soft tissue for primary closure after implant placement. Conclusion: This approach provides a tension-free primary closure of the socket after immediate implant placement. This protects the healing site from the oral environment. Schlagwörter: Immediate implant placement, soft tissue coverage, case report