Evolution of Aesthetic Dentistry

One of the main goals of dental treatment is to mimic teeth and design smiles in a most natural and aesthetic manner, based on the individual and specific needs of the patient. Possibilities to reach that goal have significantly improved over the last decade through new and specific treatment modalities, steadily enhanced and more aesthetic dental materials, and novel techniques and technologies. This article gives an overview of the evolution of aesthetic dentistry over the past 100 y from a historical point of view and highlights advances in the development of dental research and clinical interventions that have contributed the science and art of aesthetic dentistry. Among the most noteworthy advancements over the past decade are the establishment of universal aesthetic rules and guidelines based on the assessment of natural aesthetic parameters, anatomy, and physiognomy; the development of tooth whitening and advanced restorative as well as prosthetic materials and techniques, supported by the pioneering discovery of dental adhesion; the significant progress in orthodontics and periodontal as well as oral and maxillofacial surgery; and, most recently, the implementation of digital technologies in the 3-dimensional planning and realization of truly natural, individual, and aesthetic smiles. In the future, artificial intelligence and machine learning will likely lead to automation of aesthetic evaluation, smile design, and treatment-planning processes.

Barrel maturation, oak alternatives and micro-oxygenation: influence on red wine aging and quality

The impact of micro-oxygenation (MOX) in conjunction with a variety of oak alternatives on phenolic composition and red wine aging was investigated and compared with traditional barrel aging. Although several studies concluded that MOX give similar results to barrel aging, few have compared them directly and none directly compared MOX with and without wood alternatives and barrel aging. Results confirmed that MOX had a positive effect on colour density, even after 5 months of bottle aging. This is supported by an increase in polymeric phenol and pigment content not only with aging but in the MOX compared to barrel matured wine treatments. Descriptive analysis showed that MOX in combination with wood alternatives such as oak chips and staves could mimic short term (six months) barrel aging in new American and French oak barrels in regards to sensory characteristics.

Image texture features as indicators of beef tenderness

Image processing techniques were developed to predict cooked-beef tenderness from fresh-beef image characteristics. Cattle from different finishing treatments were processed in a commercial plant. Two short loin steaks were sampled from each carcass; one used for sensory evaluation and the other for imaging. The samples varied significantly in both US quality grades and sensory tenderness scores. Color, marbling and texture features were extracted from the beef images. Statistical and neural network analyses were performed to relate the image features to sensory tenderness scores. Image texture features were found to be useful indicators of beef tenderness. Partial least squares and neural network models were able to predict beef tenderness from color, marbling and image texture features to R(2)-values up to 0.70.

Pork quality attributes associated with bilateral carcass variation

The objective of this study was to identify bilateral differences in pork carcass quality as influenced by single leg shackling and suspension of electrically stunned pigs. Fifty-six Genepacker x EB market barrows (118 kg) were rendered unconscious and insensible to pain via electrical stimulation. Pigs were then shackled and suspended by the right hind leg before exsanguination and remained suspended until scalding. Initial (45-min) pH values of the LM at the 10th to 11th rib interface were different (P = 0.016); shackled side loins possessed a greater i.m. pH than those loins associated with the free side of the carcass (6.26 vs. 6.10). At 24 h postmortem, loins from the shackled side had lower (P < 0.001) L* values than loins from the free side in both the sirloin (53.08 vs. 57.61) and blade (54.61 vs. 57.09) regions. Additionally, b* values were greater (P < 0.001) for loins from the shackled side than loins from the free side in the center (13.81 vs. 13.01) and blade (14.72 vs. 13.68) regions, and in the blade region, a* values were greater (P < 0.001) in the LM from the shackled side than loins from the free side (7.37 vs. 6.26). Moreover, LM chops of loins from the shackled side that were aged 21 d were rated less (P < 0.05) tough (2.74 vs. 3.95) and more (P < 0.05) juicy (4.24 vs. 3.19) than chops from the free-hanging side. However, these differences were not evident after 41 d aging. From the results of this study, it can be concluded that bilateral differences exist within the LM of a pork carcass and that these differences are likely associated with the single-leg shackling and suspension of electrically stunned pigs.

Therapy with gentamicin-PMMA beads, gentamicin-collagen sponge, and cefazolin for experimental osteomyelitis due to Staphylococcus aureus in rats

INTRODUCTION

In spite of new surgical techniques and recently developed antibiotics, there is no satisfactory solution for the treatment of chronic posttraumatic osteomyelitis. The introduction of local antibiotic treatment with gentamicin-PMMA beads according to Klemm has provided new stimuli for the treatment of chronic osteomyelitis. With the development of collagen as an absorbable carrier substance, the disadvantages of the rigid carrier system became evident. Due to the varying surgical techniques and different forms of adjuvant therapy, it is difficult to assess therapeutic methods and compare different studies. Therefore, it seemed appropriate to study the effect of local treatment with different antibiotic carriers in the setting of an animal study.

MATERIALS AND METHODS

The proven rat model for Staphylococcus aureus-induced osteomyelitis was used to compare the results of monotherapy with cefazolin, gentamicin-PMMA beads, or gentamicin-containing collagen sponge with the combination of local and systemic antibiotic treatment.

RESULTS

Single-agent therapy with parenterally administered cefazolin reduced the CFU from 3.7 x 10(6) to 2.9 x 10(4) g(-1) of tibial bone. The effect on osteomyelitis was more pronounced with the local application of antibiotics. The best results were achieved with the gentamicin-containing collagen sponge which reduced the bacterial colony count to 1.4 x 10(2) CFU/g compared with 9.8 x 10(2) CFU/g achieved with gentamicin-PMMA beads. The effect was most marked using a 4-week combination therapy with local application of the gentamicin-containing collagen sponge and systemic administration of cefazolin. In 9 of 11 animals, no bacteria could be detected in the bone.

CONCLUSION

Each of the treatment modalities resulted in a significant therapeutic effect. Due to its ability to quickly release large amounts of gentamicin, the flexible gentamicin-containing collagen sponge proved to be superior to the rigid PMMA system. Although the gentamicin-containing collagen sponge provided high antibiotic concentration at the site of implantation, an additive effect was attained when combined with systemic antibiotic treatment.

Effect of milk fat, cocoa butter, and whey protein fat replacers on the sensory properties of lowfat and nonfat chocolate ice cream

Lowfat and nonfat chocolate ice creams were made with 2.5% of milk fat, cocoa butter, or one of two whey protein-based fat replacers, Dairy Lo or Simplesse. Polydextrose was added as required so that all formulations contained the same amount of total solids. Ice cream was stored at a control temperature of-30 degrees C. Hardness, viscosity, and melting rate were measured by physical methods. Trained panelists conducted descriptive sensory analyses of the samples at 0, 6, and 12 wk. Attribute ratings were analyzed by analysis o variance with least significant difference mean separation and orthogonal contrasting. Data were also analyzed by multivariate analysis of variance with canonical variate analysis. Consumer acceptance (n = 50) did not differ among the fresh ice creams (wk 0). Ice cream containing milk fat had less intense cocoa flavor and was more resistant to textural changes over time compared with the other ice creams. Simplesse was more similar to milk fat than was Dairy Lo in its effect on brown color, cocoa flavor, cocoa character, and textural stability but was less similar in terms of thickness and mouthcoating.

Di- and oligosaccharide substrate specificities and subsite binding energies of pig intestinal glucoamylase-maltase

The substrate specificity of pig intestinal glucoamylase-maltase was investigated. The alpha-1, beta-2-glycosidic bond of the disaccharide sucrose was not hydrolyzed. Various substrates with alpha-1,4-glycosidic bonds (maltose, maltooligosaccharides) were hydrolyzed with high maximal reaction velocities. Reduction lowered the rate of hydrolysis drastically: k'0 decreases from 75 s-1 for maltose to 3 s-1 for maltitol while the K(m) value increases from 4.2 to 50 mM. Leucrose with alpha-1,5-glycosidic bond was hydrolyzed with a k'0 value of 8 s-1 and a K(m) value of 74 mM. Disaccharides with alpha-1,6-glycosidic bonds were hydrolyzed with extremely low rates: for isomaltose and isomaltulose k'0 values of 5 and 3 s-1, respectively, and K(m) values of 90 and 42 mM, respectively, were observed. Again reduction lowers the k'0 values: The corresponding disaccharide alcohols alpha-D-glucopyranosyl-1,6-sorbitol and alpha-D-glucopyranosyl-1,6-mannitol, like isomaltooligosaccharides, were not hydrolyzed. Regarding the conformation of sucrose, leucrose, and maltose previously determined by molecular dynamics simulations, a reasonable explanation for the different rates of hydrolysis could be postulated. Based on the enzyme kinetic parameters for the series of maltooligosaccharides, subsite affinities (A1) according to the subsite theory were calculated as 7.5 (A1), 17 (A2), 3.4 (A3), and 1.3 kJ/mol (A4) for subsites 1, 2, 3, and 4, respectively. The intrinsic rate constant k'int was estimated at 76 s-1.

Sensory and physical properties of ice creams containing milk fat or fat replacers

The purpose of this research was to determine the relative effects of milk fat, nonfat milk solids, or each of three whey protein type fat replacers on the flavor and texture attributes of vanillin-flavored ice cream. Descriptive sensory analyses disclosed that ice creams containing 4.8% of any of the fat replacers in place of milk fat had no demonstrable effect on vanillin flavor but increased the intensities of whey flavor, syrup flavor, and cooked milk flavor. Compared with each substitute, milk fat significantly reduced the syrup, whey, and cooked milk flavors and increased the fresh milk and cream flavors of the ice cream. Results emphasized the importance of fat as a flavor modifier and the importance of certain fat replacers as aids in improving texture.

Effect of milk fat content on flavor perception of vanilla ice cream

The effects of milk fat concentration on flavor perception of vanilla ice cream (with 0.5 to 10% fat) were studied by sensory analyses. The percentage of free vanillin in the ice cream was determined by HPLC. The HPLC data showed that the amount of free vanillin decreased when fat content increased. Perceptions of vanilla flavor and sweetness were evaluated by a trained panel using time-intensity methodology. No significant difference was found in sweetness perception. Among 11 time-intensity parameters for vanilla flavor perception, the panel found a significant difference only in the time required to reach maximum vanilla intensity. However, free-choice profiling and a consumer preference panel showed, respectively, that, as fat content was increased, sensory quality improved, and overall preference increased.

Acarbose and 1-deoxynojirimycin inhibit maltose and maltooligosaccharide hydrolysis of human small intestinal glucoamylase-maltase in two different substrate-induced modes

The inhibition of the glucoamylase-maltase-catalyzed maltose and maltooligosaccharide hydrolysis by acarbose and 1-deoxynojirimycin has been demonstrated. Acarbose and 1-deoxynojirimycin act as potent competitive inhibitors with Ki = 0.8 microM for the hydrolysis of maltose and with Ki values of 0.4 and 0.3 microM, respectively, for the hydrolysis of maltooligosaccharides. In a previous work (Günther et al., Arch. Biochem. Biophys. 327, 295-302, 1996) using maltitol and maltobionate as inhibitors we were able to discriminate two different binding modes for glucoamylase-maltase: a maltose and an oligosaccharide binding mode. Here we found that structurally quite different substances, namely, the pseudotetrasaccharide acarbose and the monomeric glucose analog 1-deoxynojirimycin, act as competitive inhibitors for maltose and maltooligosaccharide hydrolysis. The Ki values for all used maltooligosaccharides are nearly equal, but for maltose hydrolysis the Ki values are significantly higher by a magnitude factor of two. The differences concerning Ki values can be explained by means of the two-binding-mode model.

Maltitol and maltobionate act differently on maltose- and maltooligosaccharide hydrolysis by human small intestinal glucoamylase-maltase indicating two different enzyme binding modes

The hydrolysis of maltose and maltotriose at the same catalytic site of glucoamylase-maltase has been demonstrated. Maltitol acts as a competitive inhibitor, Ki = 69 (+/-10) mM, of the maltose hydrolysis and as a noncompetitive inhibitor of the hydrolysis of maltotriose, Ki = Kii = 29 (+/-4) mM, and maltotetraose, Ki = Kii = 30 (+/-3) mM. Maltobionate was not hydrolyzed by the enzyme and did not influence the maltose hydrolysis. In contrast, in hydrolysis of maltooligosaccharides it acts as an uncompetitive inhibitor. For the hydrolysis of maltotriose, Kii = 25(+/-8) mM, and maltotetraose, Kii = 30(+/-4) mM was found. According to a characteristic of this rare inhibition pattern a simultaneous decrease of the apparent Km and the apparent Vmax of maltooligosaccharide hydrolysis with increasing maltobionate concentrations was observed. We were able to discriminate two different binding modes for glucoamylase-maltase. Maltitol binds to the free enzyme (maltose binding mode) as well as to the maltooligosaccharide-enzyme complex, whereas maltobionate binds only to the oligosaccharide-enzyme complex (oligosaccharide binding mode). This could be shown by the different inhibition behaviors of maltitol and maltobionate depending on the substrate: maltose or maltooligosaccharides.

Human small intestinal sucrase-isomaltase: different binding patterns for malto- and isomaltooligosaccharides

The hydrolysis of maltose and isomaltose and of sucrose and isomaltose at two different catalytic sites of sucrase-isomaltase has been demonstrated. Maltose and sucrose are competing for the same catalytic center. This competing can be described by alternative substrate kinetics. Steady-state kinetic parameters Km and k0 (maximal reaction velocity per mol enzyme) for linear alpha-1,4 and alpha-1,6 glucosyloligosaccharides has been determined. Using these parameters subsite affinities for the catalytic sites of sucrase and isomaltase were computed. The different numbers of subsites for sucrase (2 subsites) and isomaltase (4 subsites) indicate, that the binding patterns for maltooligosaccharides and isomaltooligosaccharides are different. That means that for sucrase unproductive enzyme-maltooligosaccharide complexes are definitely less probable than the productive one. As in human small intestinal glucoamylase-maltase in the isomaltase moiety four subsites can be evaluated with affinity values (Ai): A1 = 2.6 (+/- 0.91), A2 = 13.8 (+/- 0.70), A3 = 1.1 (+/- 0.13) and A4 = 1.5 (+/- 0.13) kJ/mol using isomaltooligosaccharides. The two subsites of sucrase are evaluated to be A1 = 4.9 (+/- 0.70) and A2 = 16.7 (+/- 0.51) kJ/mol using maltooligosaccharides. The four subsite model for isomaltase and glucoamylase-maltase is an indication that these two enzymes are mechanistically homologous in binding linear glucosyl-oligosaccharides.

Calculation of subsite affinities of human small intestinal glucoamylase-maltase

Several years ago, Hiromi et al. (1973) Biochim. Biophys. Acta 302, 362-375 proposed a theory for the action patterns of glucoamylases, based on data from steady-state kinetics. The Michaelis-Menten constants (Km) and the turnover number for maltooligosaccharides were used to evaluate the subsite affinities. We have now used this method for evaluating the subsite affinities for glucoamylases(EC 3.2.1.3)-maltase (EC 3.2.1.20) from human intestinal mucosa. For calculation of the subsite affinities, A1 and A2, and the intrinsic rate constant kint, we use a modified algorithm and a computer program for nonlinear least square fitting. Considerable substrate inhibition was shown by maltotriose, minor inhibition by maltotetraose, and no inhibition by maltose and the other maltooligosaccharides. This indicates a more complex kinetic behaviour of the enzyme with respect to maltotriose. Evaluation of the subsites reveals that A2 is the main binding site (18.1 kJ/mol), whereas the other affinities, with the exception of A1, are lower than 2.5 kJ/mol.

[Results of surgical management of unstable pertrochanteric femoral fractures with the dynamic hip screw and T-plate]

The dynamic hip screw (DHS) is a widely used method of osteosynthesis. Nevertheless, supplying instable pertrochanteric fractures is problematic because the gliding screw may cause a considerable dislocation of fragments in lateral direction. Is there any alternative method disposable, bearing stability of DHS- osteosynthesis can be improved by adding a lateral T-plate. We reached full bearing stability in four cases.

Improving survival of culture bacteria in frozen desserts by microentrapment

Lactobacillus bulgaricus cells were entrapped in beads of calcium alginate and evaluated for their ability to survive freezing processes. Cells survived freezing (without agitation) in ice milk mix much better than in distilled water, and more entrapped cells survived than did cells that were not entrapped. Glycerol and mannitol were cryoprotective, but glucose was not, when each was added (6%) separately to the beads. Entrapment protected the lactobacilli in batch frozen and continuously frozen ice milk mixes. The percentage of survival for entrapped and unentrapped cells in continuously frozen ice milk approximated 90 and 40%, respectively. Lactobacilli survived better in beads with mean diameters > 30 microns than in those averaging 15 microns. Addition of entrapped lactobacilli had no measurable effect on the sensory characteristics of the ice milk.

[Cemented bipolar prosthesis in multimorbidity patients with coxarthrosis. Short- and intermediate-term results]

The treatment of coxarthrosis with the cemented Duopleet prosthesis represents an efficient alternative to total hip prosthesis in elderly and polymorbid patients. The early results show a tolerable rate of complications. The patients can be mobilized early. The mortality seems to be low. Medium-term results are satisfactory. The rate of protrusions is lower than in patients with common femoral head prosthesis. Paraarticular ossifications are seen frequently. In numerous patients we found pain with projection to the operated hip.

[Gambee single modified all-layer suture]

Our modified all-layer suture technique allows surgery of colon and rectum with a low rate of anastomotic leaks (2%). In experimental animal research on pigs we compared the modified all-layer suture with the Gambee and the stapling technique. The circulation was examined by radioactive marked microspheres, by microangiograms and by special injection preparations.

[Computer-assisted drug therapy of incomplete ileus]

Auscultation of bowel sounds has a decisive position in management of intestinal paralysis, although personal bound interpretation and documentation may give rise to problems. Our computerized electronic analysis system of bowel sounds permits easy objectivation of auscultation findings. This noninvasive method is optional a repeatable. We investigated 15 patients suffering from intestinal paralysis using this method. Good correlations between clinical findings and the results of our analysis allow reliable estimations of therapeutic measurements. Dosage of drugs influencing peristalsis is facilitated.

The serum activities of AP, gamma-GT, GLDH, GPT and CHE after complete biliary obstruction and choledochocaval fistula in the rat

The activities in serum of alkaline phosphatase, gamma-glutamyltransferase, glutamate dehydrogenase, glutamic pyruvic transaminase and cholinesterase were compared after complete biliary obstruction (CBO) and choledochocaval fistula (CCF) in the rat. CCF was used as a model of complete biliary retention without bile stasis and without increased pressure in the biliary tract. The increases in AP, GLDH and gamma-GT within 24-h post-op. show no difference between the two experimental groups. The conclusion is that the retention of biliary constituents alone is responsible for the increase in the levels of serum activity and that other conditions like bile stasis and increased pressure in the biliary tract do not play an important role in the pathogenesis of these alterations. The rise of GPT activity in CCF is of a lesser degree than in CBO.

Effect of fasting and transportation on various physiological parameters and meat quality of slaughter hogs

Forty-nine slaughter hogs were transported and fasted or fasted with no transport for 0 (no transport), 24, 48 and 72 h. Blood samples were taken before treatments were imposed and again prior to slaughter. Soft tissues of the ham were chemically analyzed and loin samples were evaluated by a sensory panel. Fasting and transportation decreased plasma triiodothyronine and hematocrit and increased plasma osmolality. Preslaughter treatment did not affect juiciness or desirability of cooked chops or percentage of fat in the ham soft tissues. These data suggest that although fasting and transporting of slaughter hogs may disrupt homeostasis of pigs, such physiological changes do not negatively affect meat quality.

Repair of complete acromioclavicular dislocation (Tossy stage III) using Balser's hook plate combined with ligament sutures

A total of 57 consecutive cases of complete acromioclavicular dislocations are reported. They were treated by open reduction and Balser's hook plate fixation supplemented by ligament suture.

Tumor markers carcinoembryonic antigen, tissue polypeptide antigen, and carbohydrate antigen 19/9 in liver diseases

The tumor markers carcinoembryonic antigen (CEA), tissue polypeptide antigen (TPA), and carbohydrate antigen 19/9 (CA19/9) have been compared with regard to their sensitivity to liver diseases. All three markers have been found to be sensitive to liver diseases, but to a different degree: TPA rises the most; CEA the least. The sensitivities of TPA and CA19/9 are higher in a group of liver diseases than, for comparison, in a group of colorectal carcinomas.

Neopterin. A tumor marker in colorectal carcinoma?

Neopterin is compared with other tumor markers in colorectal carcinoma. Its sensitivity is clearly lower than that of CEA, TPA and CA 19/9 and is even lower than the sensitivity of the erythrocyte sedimentation rate. The ability of neopterin to discriminate between different tumor stages is also lower than that of the other markers. The discriminant analysis shows that measurement of neopterin in the serum of patients with colorectal carcinoma gives no essential additional information.

Necrosis of the ascending colon in chronic hemodialysis patients. Report of three cases

Three cases of ischemic necrosis of the right colon in chronic dialysis-dependent patients are reported. Low flow states, mucosal lesions, and changes in blood viscosity are discussed as etiologic factors.

Comparison of the tumor markers CEA, TPA, and CA 19-9 in colorectal carcinoma

In 103 patients with colorectal carcinoma carcinogenic antigen, 19-9 (CEA), tissue polypeptide (TPA) and carbohydrate antigen (CA 19-9) were measured in serum. The values determined in these patients and in a control group have been converted into specificity-sensitivity diagrams. Comparison of diagrams of the three markers showed that CEA has the greatest sensitivity in colorectal carcinoma. Different ways to enhance the sensitivity by combination of the markers have been tried. By combination, however, the sensitivity of the single markers is not essentially enhanced.

[Hyperbaric oxygenation in burns]

Standardised third degree burn injuries were produced in guinea pigs and a standardized pseudomonas aeruginosa infection model was used. Therapy with oxygen under high pressure (OHP) was initiated for not experimentally infected burn wounds and for wounds contaminated with a constant number of bacteria from a certain pseudomonas aeruginosa strain. The healing process was documented by wound area determination, histological examination, and bacteriological evaluation. Not treated uninfected wounds showed better results than the ones that were treated with OHP. Infected burn wounds also healed better when they were not treated than the wounds in which OHP therapy was initiated with some delay. The immediate and consistent application of OHP therapy led to a significantly improved healing of burn wounds infected with pseudomonas aeruginosa.

Nontraumatic perforations of the small intestine

Nontraumatic perforation of the small intestine is very rarely found as a cause of acute abdominal disease. A series of 15 adult patients admitted to our hospital from 1973 to 1983 is reviewed. Underlying conditions were primary neoplasia (three patients), adhesions (three patients), intraluminal foreign bodies (two patients), metastases (two patients) and diverticulum (one patient). In four patients, the pathogenesis remained unclear (idiopathic perforations). As surgical therapy, resection and anastomosis is preferred in order to make a thorough histologic examination of the perforated bowel possible. A possible role of local drug toxicity in the pathogenesis of perforations has been discussed herein. No anastomotic leakage was observed. Four patients died (27 percent).

[Treatment of acromioclavicular dislocations with the Balser hook plate and ligament suture]

The method of operation is described, making the ligament suture safe with the hook-plate. A postoperative immobilisation is renounced by this supplying. The results of the follow-up examinations (n = 20) show no disadvantage to other operative methods. As the subjective complaints and the rate of arthrosis appear to be lower than with usual procedures of stabilisation, the supplying with the hook-plate according to Balser (additional to the ligament suture) seems to guarantee a particularly safe retention under biomechanical favourable conditions.