Measurements of the gingival papillae architecture using cone-beam computed tomography in young Chinese adults

Background The aim of this study was to measure the morphology of interdental papillae (IP) in maxillary anterior teeth using cone-beam computed tomography (CBCT). Methods Twenty-seven periodontally healthy subjects with 135 IP were evaluated by means of periodontal examination and a CBCT scan with an elastomeric matrix containing radiopaque material in position. According to the status of tooth contact and presence of IP, subjects were categorized into three groups: open contact point, complete papillae, and deficient papillae group. The papillae height (PH), facial-lingual thickness (FLT), and interdental distance (IDD) were measured. Data was analyzed with the significance level at α = 0.05. Results The mean PH values were 4.17 ± 0.51 mm, 3.99 ± 0.61 mm, and 3.99 ± 0.62 mm, for the open contact group, complete papilla, and deficient papilla group, respectively. The PH values of the recorded sites among central incisors, lateral incisors, and canine were 4.13 ± 0.56 mm, 3.87 ± 0. 63 mm, and 4.07 ± 0.58 mm, respectively. No statistically significant differences of the PH values were determined between the above three tested groups as well as between the different sites (p > 0.05). The IDD values obtained from the complete papilla group were significantly lower than the other tested groups (p < 0.05). Conclusion The contact point condition of upper anterior sextants may not influence the presence and dimension of the IP in periodontally healthy subjects.

Receiving, or ‘Adopting’, Donated Embryos to Have Children: Parents Narrate and Draw Kinship Boundaries

Existing research suggests that embryo donation (ED) may be seen as similar to adoption by those who donate or receive embryos, or it may not. Our qualitative study explored whether having a child via embryo donation initiated kinship connections between embryo donor and recipient families as interpreted by recipient parents. Interviews were conducted with five parents from four families whose child(ren) had been born via embryo donation. All four families had an open-contact relationship set up with the couples who donated their embryos through an agency in the USA. Narrative thematic analysis of interview data and visual family map drawings were used to explore kinship conceptualizations. We conclude that the dilemma experienced by parents who have a child via embryo donation is to decide how to reconcile their child’s different genetic heritage, when gestation and upbringing both clearly boundary family membership solely within the recipient family. While some families were still struggling with this dilemma, one solution embarked upon by some parents when drawing their family map was to expand family membership, not only on the basis of genetics, but also via an appreciation of shared family and community values too.

Atraumatic Restoration of Vertical Food Impaction with an Open Contact Using Flowable Composite Resin Aided by Cerclage Wire under Tension

To date, treating vertical food impaction with open contact effectively, especially with an atraumatic therapy, remains a challenge. In this study, we developed a simple, atraumatic, and economic therapeutic measure to treat vertical food impaction. The scientific rationale of our therapeutic technique is to restore an intact and firm proximal contact with proper location and form relationships to prevent forceful interproximal wedging of food, which in turn protects interdental papilla. We performed the procedure using flowable composite resin or composite resin cement with the aid of a cerclage wire under tension to rebuild the contact area. The reported method is especially useful for some challenging clinical cases, such as food impaction after crown and inlay on onlay restoration, and some conventional treatment methods, such as contouring the marginal ridge and developmental grooves, are ineffective.

Transient Thermal Analysis as a Test Method for the Reliability Investigation of High Power LEDs during Temperature Cycle Tests

Light emitting diodes (LEDs) are today standard and mature light sources. They have several key advantages, like small size, low energy consumption and long lifetime. However, high reliability of the LED system is required to achieve long lifetime of the light source. Thermo-mechanical stress due to temperature cycle causes failure of electronic systems. The electronic component itself or the interconnect device, e.g. printed circuit board (PCB) might fail. In many cases, the weakest link is found to be the solder interconnect between package and the board. Cracking of the interconnect causes an open contact and the system fails. In this paper we compare the existing methods to investigate LED interconnect failures during temperature cycle tests like the simple “light-on-test”, electric resistance measurement and the shear test. We describe and introduce the transient thermal analysis as a measurement method. We present the first reliability data analysis with transient thermal analysis of ceramic high power LED packages on Al-IMS during air to air thermal shock test (−40°C to +125°C) and correlate it with cross sections. We demonstrate the sensitivity of the thermal analysis to detect solder joint failures of the assembly. We compare the results with electric resistance measurements and light on tests and show that the resolution is significantly higher compared to the methods applied today. The sensitivity of the method enables us to detect the crack in a solder joint much earlier than the final failure of the joint, i.e. the open contact.