Orthodontic Treatment Need of Austrian Schoolchildren in the Mixed Dentition Stage

Malocclusal traits can impair dental health and aesthetical appearance. The index of orthodontic treatment need (IOTN) identifies the patients who benefit the most from orthodontic treatment. The aim of this study was to assess the malocclusion frequencies and the orthodontic treatment need among Austrian children in the mixed dentition stage, since there is no pre-existing data from Austria. In the present study, 157 children aged between 8 and 10 years were examined. Following an anamnesis questionnaire, which included a question about the parents' perceived treatment need, the children were examined clinically and dental impressions were taken. The sagittal molar relationship, overjet, overbite and the presence of cross- or scissor bite were registered. The treatment need was assessed using the dental health component (DHC) of the index of orthodontic treatment need (IOTN). 64.3% (95% CI [56.8, 71.8]) of the children showed Angle class I molar relation, 33.1% (95% CI [25.8, 40.5]) class II and 2.5% (95% CI [0.1, 5.0]) Angle class III relation. Crossbite was found in 36.3% (95% CI [28.8, 43.8]) of the participants. A treatment need for medical reasons (IOTN 4 or 5) was found in 30.6% (95% CI [23.4, 37.8]). There was no statistically significant relationship between objective treatment need and the parents' perception. The malocclusion frequencies and the treatment need assessed in the present study appeared to be comparable to those assessed in other countries. The data supports the opinion that orthodontic screening is important and necessary at this stage of dental development, also due to the discordance between objective and perceived treatment need

In Vitro Analysis of the Fracture Resistance of CAD/CAM Denture Base Resins

Computer-aided design and computer-aided manufacturing (CAD/CAM) denture base manufacturers claim to produce their resin pucks under high heat and pressure. Therefore, CAD/CAM dentures are assumed to have enhanced mechanical properties and, as a result, are often produced with lower denture base thicknesses than conventional, manually fabricated dentures. The aim of this study was to investigate if commercially available CAD/CAM denture base resins have more favourable mechanical properties than conventionally processed denture base resins. For this purpose, a series of three-point bending tests conforming to ISO specifications were performed on a total of 80 standardised, rectangular CAD/CAM denture base resin specimens from five different manufacturers (AvaDent, Baltic Denture System, Vita VIONIC, Whole You Nexteeth, and Wieland Digital Dentures). A heat-polymerising resin and an autopolymerising resin served as the control groups. The breaking load, fracture toughness, and the elastic modulus were assessed. Additionally, the fracture surface roughness and texture were investigated. Only one CAD/CAM resin showed a significantly increased breaking load. Two CAD/CAM resins had a significantly higher fracture toughness than the control groups, and all CAD/CAM resins had higher elastic moduli than the controls. Our results indicate that CAD/CAM denture base resins do not generally have better mechanical properties than manually processed resins. Therefore, the lower minimum denture base thicknesses should be regarded with some caution

Clinical Outcome Following Surgical Repair of Small Versus Large Orbital Floor Fractures Using Polyglactin 910/Polydioxanone (Ethisorb®)

The aim of this retrospective study was to evaluate the clinical outcome of surgical management of small versus large, isolated orbital floor fractures (OFFs) using polyglactin 910/polydioxanone (Ethisorb®). Covering a four-year period (2010–2013), all records concerning midfacial fractures with involvement of the orbit were screened. Isolated fractures of the orbital floor as well as combined injuries of the orbital floor and medial wall that had been treated surgically using polyglactin 910/polydioxanone (Ethisorb®) were included. Patients underwent a preoperative, a postoperative, and a late ophthalmologic assessment. The clinical outcomes of surgically managed small OFFs up to 2 cm2 were statistically analyzed and compared to clinical results in larger defects. The final sample included 61 patients (25 women, 36 men). Fractures up to 2 cm2 were found in 33 patients (54.1%), whereas 28 patients (45.9%) suffered from OFFs larger than 2 cm2. The clinical outcomes did not significantly differ between both sample categories, and statistical analysis showed a power of 0.91 to detect a potentially existing difference. On final examination, 52 patients were free of any clinical symptoms, whereas minor issues were found in seven subjects, and two patients suffered from severe impairment. In conclusion, polyglactin 910/polydioxanone (Ethisorb®) seems to be a suitable material for surgical repair of both small and large OFFs