Is there a difference in surgical accuracy following bimaxillary surgery between cleft and non-cleft patients?

OBJECTIVES: To assess the surgical accuracy of 3D virtually planned orthognathic surgery among patients with and without cleft. MATERIALS AND METHODS: This retrospective cohort study included cleft and non-cleft patients with class III malocclusion who underwent bimaxillary surgery. CBCT scans were acquired before and immediately after surgery. 3D virtual surgical planning (VSP) was performed using CBCT and digitalized dentition data. All orthognathic surgeries were performed by the same surgeons using interocclusal splints. The primary outcome variable was surgical accuracy, defined as the difference between the planned and surgically achieved maxillary movements, quantified in six degrees of freedom. Analysis of covariance was used to test for intergroup differences in surgical accuracy after correcting for differences in the magnitude of planned surgical maxillary movements. RESULTS: Twenty-eight cleft and 33 non-cleft patients were enrolled, with mean ages of 18.5 and 25.4 years, respectively (P=0.01). No significant gender difference was present between the groups (P=0.10). After adjustment for small differences in surgical movements, no significant differences in surgical accuracy were observed between cleft and non-cleft patients. CONCLUSION: The present study demonstrates that high surgical accuracy in maxillary movements can be achieved in both cleft and non-cleft patients using VSP and interocclusal splints. CLINICAL RELEVANCE: Orthognathic cases with cleft can be performed with 3D VSP to obtain a satisfactory surgical accuracy.

Solution scattering studies of the hierarchical assembly of porphyrin trimers based on benzene triscarboxamide.

The self-assembly of achiral and chiral porphyrin trimers based on benzene triscarboxamide in solution is studied with the help of NMR, FT-IR, UV-vis, and CD spectroscopy. These studies revealed that in apolar solvents the porphyrin trimers self-assembled in columnar stacks via a combination of hydrogen bonding and π-π stacking interactions. While the critical aggregation constant is about 0.2 mM in chloroform, aggregation already occurs at micromolar concentrations in n-hexane. Small angle neutron scattering (SANS) studies in chloroform, toluene, and n-hexane confirmed aggregation of the trimers into columnar stacks. In chloroform and n-hexane, but not in toluene, the trimers gelated the solvent. In chloroform the stacks of the achiral trimer were found to contain on average about 70 molecules, while in toluene the stacks were much smaller and contained on average 7-9 molecules. In n-hexane the SANS studies revealed that the chiral trimer formed a gel with an average mesh size of the transient network of chains of approximately 90 nm, with chains being built up from effective cylindrical aggregates with an average length of 20 nm.

AFLP markers as a tool to reconstruct complex relationships: A case study in Rosa (Rosaceae).

The genus Rosa has a complex evolutionary history caused by several factors, often in conjunction: extensive hybridization, recent radiation, incomplete lineage sorting, and multiple events of polyploidy. We examined the applicability of AFLP markers for reconstructing (species) relationships in Rosa, using UPGMA clustering, Wagner parsimony, and Bayesian inference. All trees were well resolved, but many of the deeper branches were weakly supported. The cluster analysis showed that the rose cultivars can be separated into a European and an Oriental cluster, each being related to different wild species. The phylogenetic analyses showed that (1) two of the four subgenera (Hulthemia and Platyrhodon) do not deserve subgeneric status; (2) section Carolinae should be merged with sect. Cinnamomeae; (3) subsection Rubigineae is a monophyletic group within sect. Caninae, making sect. Caninae paraphyletic; and (4) there is little support for the distinction of the five other subsections within sect. Caninae. Comparison of the trees with morphological classifications and with previous molecular studies showed that all methods yielded reliable trees. Bayesian inference proved to be a useful alternative to parsimony analysis of AFLP data. Because of their genome-wide sampling, AFLPs are the markers of choice to reconstruct (species) relationships in evolutionary complex groups.

The establishment of 'essential derivation' among rose varieties, using AFLP.

In the International Union for the Protection of New Varieties of Plants Act of 1991, mutation is mentioned as one of the mechanisms to obtain an 'essentially derived' variety (EDV). For the implementation of the EDV concept in the case of mutation, it is important that the level of genetic relatedness between an initial variety and derived mutant varieties can clearly be distinguished from the level of relatedness between arbitrary pairs of varieties without a derivation relation. Conditions to be fulfilled for such a distinction include enough genetic differentiation in the germplasm pool of interest, sufficiently low levels of genomic sampling error and technical laboratory error and high reproducibility within and between laboratories. In rose, mutants or 'sports' are frequently observed during multiplication, making it a suitable crop for studying the possibilities for introduction of the EDV concept in ornamentals. We studied genetic similarities among 83 rose varieties, including 13 mutant groups. Twelve AFLP primer combinations generated 284 polymorphic markers and 114 monomorphic (fixed) bands. Pair-wise Jaccard similarities between original varieties and derived mutants were close to 1.0 (>0.96), whereas all similarities between original varieties were below 0.80, with 75% of the non-mutant similarities even being below 0.50. Values less than 1.0 for similarity among original varieties and their mutants were to a major extent due to scoring errors. Error rates in automated scoring proved to be lower than those in manually scored and transferred data. Experimental errors, even between laboratories, turned out to be very small. On the basis of a consistent and large difference between similarities, relations between an original variety and its mutants can easily be identified and distinguished from relations between original varieties. These results open the way for implementing the essential derivation concept in rose.

Structural and physical properties of the ferromagnetic tris-dithiooxalato compounds, A[M(II)Cr(III)(C(2)S(2)O(2))(3)], with A(+) = N(n-C(n)()H(2)(n)(+1))(4)(+) (n = 3-5) and P(C(6)H(5))(4)(+) and M(II) = Mn, Fe, Co, and Ni.

The structural and magnetic properties of the tris-dithiooxalato salts, A[M(II)Cr(C(2)S(2)O(2))(3)], have been investigated with A(+) = PPh(4)(+), N(n-C(n)()H(2)(n)()(+1))(4)(+), with n = 3-5, where M(II) is Mn, Fe, Co, and Ni. With the exception of A[MnCr(C(2)S(2)O(2))(3)], all the salts are ferromagnets with Curie temperatures, T(c), between 5 and 16 K. In contrast to the corresponding oxalates which are ferromagnetic, the A[MnCr(C(2)S(2)O(2))(3)] compounds are paramagnetic above 2 K. Powder neutron diffraction studies of d(20)-PPh(4)[FeCr(C(2)S(2)O(2))(3)] indicate that no structural phase transitions occur between 2.4 and 285 K and that the coefficient of linear expansion is four times larger for the c-axis than for the a-axis. The crystal structure refined from powder neutron diffraction data confirms the honeycomb layer arrangement observed in the related bimetallic tris-oxalate salts. The Mössbauer spectra reveal that the iron(II) in PPh(4)[FeCr(C(2)S(2)O(2))(3)] is coordinated mainly to six oxygen atoms of the dithiooxalato ligand but with a minor component of sulfur coordination that increases with aging of the sample; the iron(II) is high-spin in both cases. Powder neutron diffraction profiles of d(20)-PPh(4)[FeCr(C(2)S(2)O(2))(3)] below T(c) show magnetic intensity with a q = 0 propagation vector, confirming the presence of ferromagnetic order.