Microguided Endodontics: Accuracy of a Miniaturized Technique for Apically Extended Access Cavity Preparation in Anterior Teeth.

INTRODUCTION: The aim of this study was to assess the accuracy of guided endodontics in mandibular anterior teeth by using miniaturized instruments. This technique is designed to treat teeth with pulp canal calcifications and narrow roots by using a printed template that guides a bur to the calcified root canal. METHODS: Sixty sound mandibular anterior teeth were used in 10 mandibular models. Preoperative surface and cone-beam computed tomography scans were matched by using the coDiagnostix software. Virtual planning was performed for the access cavities, and templates were used for guidance. The templates were produced by a three-dimensional printer. Two operators performed the access cavities. A postoperative cone-beam computed tomography scan was superimposed on the virtual plan, and the deviation was measured in 3 dimensions and angles. Descriptive statistical analyses were performed, and 95% confidence intervals were calculated for both operators and each measured aspect. RESULTS: The deviations between the planned- and prepared-access cavities were low, with means ranging from 0.12 to 0.13 mm for different aspects at the base of the bur and 0.12 to 0.34 mm at the tip of the bur. The mean of angle deviation was 1.59°. A considerable overlap of the 95% confidence intervals indicated no significant difference between the operators. The mean treatment time, including planning and preparation, was approximately 10 minutes per tooth. CONCLUSIONS: Microguided endodontics provides an accurate, fast, and operator-independent technique for the preparation of apically extended access cavities in teeth with narrow roots such as mandibular incisors.

Guided Endodontics: a novel treatment approach for teeth with pulp canal calcification and apical pathology.

AIM: To present a new treatment approach for teeth with pulp canal calcification (PCC) which require root canal treatment. CASE: A 15-year-old male patient presented with pain of his upper right central incisor. The tooth showed signs of apical periodontitis. Due to PCC, location of the root canal was judged to be difficult and associated with a high risk of perforation. A cone beam computed tomography (CBCT) and an intra-oral surface scan were performed and matched using software for virtual implant planning. After planning the position of the drill for root canal location, a virtual template was designed, and the data were exported as an STL file and sent to a 3D printer for template fabrication. The template was positioned on the anterior maxillary teeth. A specific drill was used to penetrate through the obliterated part of the root canal and obtain minimally invasive access to the apical part. The root canal was accessible at 9 mm distance from the apex. Further root canal preparation was carried out using an endodontic rotary instrumentation system. After an interappointment dressing for 4 weeks, the root canal was filled with vertically condensed gutta-percha using an epoxy sealer. The access cavity was restored with a composite material. After 15 months, the patient was clinically asymptomatic with no pain on percussion. The radiograph showed no apical pathology. CONCLUSIONS: The presented guided endodontic approach seems to be a safe, clinically feasible method to locate root canals and prevent root perforation in teeth with PCC.

Proof of concept for microarray-based detection of DNA-binding oncogenes in cell extracts.

The function of DNA-binding proteins is controlled not just by their abundance, but mainly at the level of their activity in terms of their interactions with DNA and protein targets. Moreover, the affinity of such transcription factors to their target sequences is often controlled by co-factors and/or modifications that are not easily assessed from biological samples. Here, we describe a scalable method for monitoring protein-DNA interactions on a microarray surface. This approach was designed to determine the DNA-binding activity of proteins in crude cell extracts, complementing conventional expression profiling arrays. Enzymatic labeling of DNA enables direct normalization of the protein binding to the microarray, allowing the estimation of relative binding affinities. Using DNA sequences covering a range of affinities, we show that the new microarray-based method yields binding strength estimates similar to low-throughput gel mobility-shift assays. The microarray is also of high sensitivity, as it allows the detection of a rare DNA-binding protein from breast cancer cells, the human tumor suppressor AP-2. This approach thus mediates precise and robust assessment of the activity of DNA-binding proteins and takes present DNA-binding assays to a high throughput level.

GPSDB: a new database for synonyms expansion of gene and protein names.

UNLABELLED: We present a new database, GPSDB (Gene and Protein Synonyms DataBase) which collects gene/protein names, in a species specific way, from 14 main biological resources. A web-based search interface gives access to the database: given a gene/protein name, it retrieves all synonyms for this entity and queries Medline with a set of user-selected terms. AVAILABILITY: GPSDB is freely available from http://biomint.oefai.at/ CONTACT: johann@oefai.at.

The evolution of the Proteocephalidea (Platyhelminthes, Eucestoda) based on an enlarged molecular phylogeny, with comments on their uterine development.

We present a molecular phylogeny of the Proteocephalidea based on 28S rDNA sequence data that is a follow-up to the paper by Zehnder & Mariaux (1999). Twenty-three new sequences, including three outgroups are added in our new data-set. The Gangesiinae Mola, 1929 and the Acanthotaeniinae Freze, 1963 appear to be the most primitive clades. They are followed by a robust clade comprising the Palaearctic Proteocephalinae Mola, 1929 from freshwater fishes. The structure of the more derived clades, comprising most Neotropical and Nearctic species, is less resolved. At the nomenclatural level, we erect a new genus, Glanitaenia n. g. for G. osculata (Goeze, 1782) n. comb., previously Proteocephalus osculatus, and define an aggregate for the Palaearctic Proteocephalus Weinland, 1858. After a re-examination of all of the studied taxa, we identify two types of uterine development and show the importance of this character for the systematics of the order. Our phylogeny does not support the classical view of a Neotropical origin for the Proteocephalidea but rather favours an Old World origin of the group either in saurians or Palaearctic Siluriformes.