Evaluation of molar teeth and buds in patients submitted to mandible distraction: Long-term results

Background: Despite all benefits offered by mandible distraction, complications and long-term consequences need to be evaluated to define its safety and morbidity. Forty mandible distractions were studied. Panoramic mandible radiographs obtained preoperatively, during distraction, and during the postoperative period were reviewed, with the intention of evaluating development and complications of molar buds and teeth in the distraction area. Methods: The mean patient age was 8.1 years. Twenty-five patients had craniofacial microsomia (one associated with a no. 10 facial cleft), five had temporomandibular joint ankylosis, two had familiar cases of auriculocondylar syndrome, one had a Tessier no. 30 facial cleft, and one had Treacher Collins syndrome. The severity of mandible hypoplasia was Pruzansky grade I in four cases, grade IIA in eight cases, grade 1113 in 16 cases, and grade III in one case. Mean radiographic follow-up was 44.8 months. Results: Molar buds located in the distraction area erupted without any deformity or displacement in 18 sides (45 percent). Fourteen cases presented distalization of a dental bud to a superior position in the mandibular ramus (four migrated back to the original position). Six molar buds presented perforations, four had shape deformities (two caused by dental fracture), and two had dental root injuries followed by root absorption lately. One case developed a dentigerous cyst. Conclusions: Almost half of the patients did not have any molar bud or tooth alterations after mandible distraction, and more than 20 percent presented only bud distalization. Therefore, preventive bud enucleation or tooth extraction should be avoided before mandible distraction.

Robust algorithms for solving stochastic partial differential equations

A robust semi-implicit central partial difference algorithm for the numerical solution of coupled stochastic parabolic partial differential equations (PDEs) is described. This can be used for calculating correlation functions of systems of interacting stochastic fields. Such field equations can arise in the description of Hamiltonian and open systems in the physics of nonlinear processes, and may include multiplicative noise sources. The algorithm can be used for studying the properties of nonlinear quantum or classical field theories. The general approach is outlined and applied to a specific example, namely the quantum statistical fluctuations of ultra-short optical pulses in chi((2)) parametric waveguides. This example uses a non-diagonal coherent state representation, and correctly predicts the sub-shot noise level spectral fluctuations observed in homodyne detection measurements. It is expected that the methods used wilt be applicable for higher-order correlation functions and other physical problems as well. A stochastic differencing technique for reducing sampling errors is also introduced. This involves solving nonlinear stochastic parabolic PDEs in combination with a reference process, which uses the Wigner representation in the example presented here. A computer implementation on MIMD parallel architectures is discussed. (C) 1997 Academic Press.

Social adaptation of children with mild intellectual disability: Effects of partial integration within primary school classes

is study examined the social adaptation of children with mild intellectual disability who were either (a) partially integrated into regular primary school classes, or (b) full-time in separate classes, All of the children were integrated in sport and play activities with the whole school. Consistent with previous research, children with intellectual disability were less socially accepted than were a matched group of control children. Children in partially integrated classes received more play nominations than those in separate classes, brit there was no greater acceptance as a best friend. On teachers' reports, disabled children had higher levels of inappropriate social behaviours, but there was no significant difference in appropriate behaviours. Self-assessments by integrated children were more negative than those by children in separate classes, and their peer-relationship satisfaction was lower. Ratings by disabled children of their satisfaction with peer relationships were associated with ratings of appropriate social skills by themselves and their teachers, and with self-ratings of negative behaviour. The study confirmed that partial integration can have negative consequences for children with an intellectual disability.

Assessment of immediate conservative breast surgery reconstruction: A classification system of defects revisited and an algorithm for selecting the appropriate technique

Background: Although various techniques have been used for breast conservation surgery reconstruction, there are few studies describing a logical approach to reconstruction of these defects. The objectives of this study were to establish a classification system for partial breast defects and to develop a reconstructive algorithm. Methods: The authors reviewed a 7-year experience with 209 immediate breast conservation surgery reconstructions. Mean follow-up was 31 months. Type I defects include tissue resection in smaller breasts (bra size A/B), including type IA, which involves minimal defects that do not cause distortion; type III, which involves moderate defects that cause moderate distortion; and type IC, which involves large defects that cause significant deformities. Type II includes tissue resection in medium-sized breasts with or without ptosis (bra size C), and type III includes tissue resection in large breasts with ptosis (bra size D). Results: Eighteen percent of patients presented type I, where a lateral thoracodorsal flap and a latissimus dorsi flap were performed in 68 percent. Forty-five percent presented type II defects, where bilateral mastopexy was performed in 52 percent. Thirty-seven percent of patients presented type III distortion, where bilateral reduction mammaplasty was performed in 67 percent. Thirty-five percent of patients presented complications, and most were minor. Conclusions: An algorithm based on breast size in relation to tumor location and extension of resection can be followed to determine the best approach to reconstruction. The authors` results have demonstrated that the complications were similar to those in other clinical series. Success depends on patient selection, coordinated planning with the oncologic surgeon, and careful intraoperative management.

Bariatric Surgery in Adolescents: Preliminary 1-year Results with a Novel Technique (Santoro III)

Background Bariatric surgery (BS) was recognized as the only treatment for morbid obesity in adolescents. Classic surgical procedures are based on mechanical restriction and/or malabsorption, resulting in a large number of possible complications and demanding lifelong medical attention. A novel BS design, the Santoro III procedure, relies on modifying secretion of the satiogenic hormones GLP-1 and PYY. This approach avoids common BS complications such as prostheses, narrow anastomoses, excluded segments, and malabsorption. This study describes the 1-year follow-up of the first ten adolescents operated on using the Santoro III technique in a pediatric surgical service. Methods Ten adolescents, mean age 16.1 +/- 1.7 years with body mass index (BMI) greater than 40 kg/m(2) (range 44 to 72 kg/m(2)), refractory to at least 2 years of medical weight loss treatment were selected by a multidisciplinary team to undergo BS. This operation consists of a sleeve gastrectomy with enteroomentectomy and partial gastro-ileal derivation. Results After 1 year, mean body weight decreased from 140.3 to 88.6 kg, and BMI decreased from 52.8 +/- 9.5 kg/m(2) to 33.4 +/- 7.7 kg/m(2), with percent of excess BMI lost as 83.9 +/- 17.1%. Glucose, insulin, total cholesterol, LDL-cholesterol, and triglyceride levels decreased significantly, while HDL-cholesterol, hemoglobin, and albumin levels remained unchanged. There were no mortalities or reoperations. The two complications that presented during the trial (intraperitoneal abscess and polyneuritis) resolved with medical treatment without sequelae. All the patients returned to their normal activities and their BMI began to stabilize approximately 2 years following surgery. Conclusions The Santoro III procedure is an attractive option for adolescent BS, with promising 1-year follow-up results. These initial studies should be monitored for long-term outcomes and confirmed on a larger group of patients.

Newly Formed Bone in Mandible Decortication Experimental Model Using rhBMP-2 Evaluated by Densitometric Study

The purpose of this study was to evaluate the newly formed bone, comparing two different carriers for rhBMP-2, using the decortication and nondecorticatication surgical technique in Wistar rat mandibles, evaluated by radiographic densitometry method. It was used fifty six animals according to specific treatment, which were sacrificed after 3 and 6 weeks after this. It was concluded that the decortication surgical technique was able to optimize the osteoinduction properties of the rhBMP-2, independently of the material carrier used and the period of time, according to radiographic densitometry technique.

Loss of samples in the tissue microarray technique: comparison between slides using adhesive tape and silanized slides

The tissue microarray (TMA) technique allows multiple tissue samples in a single block. Commercial adhesive tape is used to avoid the loss of tissue samples during the immunostaining process. Few reports exist in the literature comparing the use of these adhesive tapes to other adhesive techniques. The objective of this study was to compare loss of sections adhered to slides using commercial adhesive tapes versus using silanized only slides. TMA was constructed with varying tissues using a fixed-base device (Beecher Instruments), placing 108 cylinders of 1 mm diameter in duplicate, spaced 1.2 mm apart. Section of 4 mu m were cut from the TMA block and adhered to 30 silanized slides and 30 commercial glass slides using adhesive tape, according to manufacturer`s recommendations. Vimentin immunoexpression was evaluated by immunohistochemistry. Antigenic recovery was realized in citrate buffer using a microwave oven. Cylinder loss in the immunohistochemical process was quantified and expressed as: total (>80%), almost complete (75-79%), or partial (50-74%). The commercial adhesive tape group presented lesser total loss (1.1 versus 6.4%), almost complete loss (2.2 versus 3.5%), and partial loss (2.1 versus 3.8%) than the silanized slide group (ANOVA, P < 0.05). The sum of total and almost complete losses in the silanized slide group was 9.9%, greater than the losses in slides using commercial adhesive tapes (3.3%) and less than reported and considered acceptable in the literature (10-30%). In conclusion, the use of silanized only slides presents very satisfactory results, requires less training, and reduces costs significantly, thus justifying their use in research.

Biofilm microbial communities of denture stomatitis

Introduction: Denture stomatitis is a common lesion that affects denture wearers. Its multifactorial etiology seems to depend on a complex and poorly characterized biofilm. The purpose of this study was to assess the composition of the microbial biofilm obtained from complete denture wearers with and without denture stomatitis using culture-independent methods. Methods: Samples were collected from healthy denture wearers and from patients with denture stomatitis. Libraries comprising about 600 cloned 16S ribosomal DNA (rDNA) bacterial sequences and 192 cloned eukaryotic internal transcribed spacer (ITS) region sequences, obtained by polymerase chain reactions, were analyzed. Results: The partial 16S rDNA sequences revealed a total of 82 bacterial species identified in healthy subjects and patients with denture stomatitis. Twenty-seven bacterial species were detected in both biofilms, 29 species were exclusively present in patients with denture stomatitis, and 26 were found only in healthy subjects. Analysis of the ITS region revealed the presence of Candida sp. in both biofilms. Conclusion: The results revealed the extent of the microbial flora, suggesting the existence of distinct biofilms in healthy subjects and in patients with denture stomatitis.

Total gastric transposition is better than partial gastric tube esophagoplasty for esophageal replacement in children

Whenever the surgeon uses the stomach as an esophageal substitute, either one of two techniques is generally performed: total gastric transposition or gastric tube esophagoplasty. No existing reports compare the complications associated with these two surgical procedures. The purpose of this study is to review the authors` experience with total gastric transposition and verify whether this technique is superior to gastric tube esophagoplasty in children by comparing the main complications with those reported in the publications of gastric tubes esophagoplasties in the English language literature published in the last 38 years. A total of 35 children underwent total gastric transposition according to the classical technique. Most of these patients (27, or 77.1%) had long gap esophageal atresia. The most frequently observed complications were compared to those reported in nine studies of gastric tube esophagoplasty comprising 184 patients. Mortality and graft failure rates were also compared. Seven patients (20.0%) presented with leaks, all of which closed spontaneously. Six children were reoperated, three experienced gastric outlet obstruction secondary to axial torsion of the stomach placed in the retrosternal space and the other three experienced delayed gastric emptying that required revision of the piloroplasty. There were two deaths (5.7%) and no graft failure. Strictures were observed in five patients (14.2%) and all of these were resolved with endoscopic dilatations. Six patients had diarrhea that spontaneously resolved. In the late follow-up period, all patients were on full feed and thriving well. The comparisons with gastric tube patients demonstrated that the total gastric transposition group presented with significantly less leaks and strictures (P = 0.0001 and 0.001, respectively). The incidence of death and graft failure was not statistically different. In conclusion, gastric transposition is as a simple technical procedure for esophageal replacement in children with satisfactory results, and is superior to gastric tube esophagoplasty.

Tunicamycin inhibition of N-glycosylation of alpha-glucosidase from Aspergillus niveus: partial influence on biochemical properties

Treatment of Aspergillus niveus with 30 mu g tunicamycin/ml did not interfere with alpha-glucosidase production, secretion, or its catalytic properties. Fully- and under-glycosylated forms of the enzyme had similar molecular masses, similar to 56 kDa. Moreover, the absence of N-glycans did not affect either pH optimum (6.0) or temperature optimum (65A degrees C). The K(m) and V(max) values of under- and fully-glycosylated forms of alpha-glucosidase were similar when assessed for hydrolysis of starch (similar to 0.6 mg/ml, similar to 350 mu mol glucose per min per ml), maltose (similar to 0.54 mu mol, similar to 330 mu mol glucose per min per ml) and p-nitrophenyl-alpha-d-glucopyranoside (similar to 0.54 mu mol, similar to 8.28 mu mol p-nitrophenol per min per ml). However, the under-glycosylated form was sensitive to high temperatures probably because, in addition to stabilizing the protein conformation, glycosylation may also prevent unfolded or partially folded proteins from aggregating. Binding assays clearly showed that the under-glycosylated protein did not bind to concanavalin A but has conserve its jacalin-binding property, suggesting that only O-glycans might be intact on the tunicamycin treated form of the enzyme.

Expression of Extracellular Matrix Proteins in Human Dental Pulp Stem Cells Depends on the Donor Tooth Conditions

Introduction: Stem cells are characterized by the ability to renew themselves through mitotic cell division and differentiating into a diverse range of specialized cell types. An important source of adult stem cells is the dental pulp. In dentistry, regenerative strategies are of importance because of hard dental tissue damage especially as result of caries lesions, trauma, or iatrogenic procedures. The regeneration of dental tissues relies on the ability of stem cells to produce extracellular (ECM) proteins encountered in the dental pulp tissue. Thus, the aim of this study was to analyze the expression and distribution of proteins encountered in dental pulp ECM (type I collagen, fibronectin, and tenascin) in stem cells. Methods: Human immature dental pulp stem cells (hIDPSCs) from deciduous (DL-1 and DL-4 cell lines) and permanent (DL-2) teeth were used. The distribution of ECM proteins was observed using the immunofluorescence technique. The gene expression profile was evaluated using reverse transcription polymerase chain reaction (RT-PCR) analysis. Results: Positive reactions for all ECM proteins were observed independently of the hIDPSCs analyzed. Type I collagen appeared less evident in DL-2 than in other hIDPSCs. Fibronectin and tenascin were less clear in DL-4. The RT-PCR reactions showed that type I collagen was lesser expressed in the DL-2 cells, whereas fibronectin and tenascin were similarly expressed in all hIDPSCs. Conclusions: The distribution and expression of ECM proteins differ among the hIDPSCs. These differences seemed to be related to the donor tooth conditions (deciduous or permanent, retained or erupted, and degree of root reabsorption). (J Endod 2010;36:826-831)

The Effect of Fluoride Therapies on the Morphology of Bleached Human Dental Enamel

The aim of this in vitro study was to evaluate qualitatively the surface morphology of enamel bleached with 35% hydrogen peroxide (HP) followed by application of fluoridated agents. Forty intact pre molars were randomly distributed into four groups (n = 10), treated as follows: Group I (control group) remained stored in artificial saliva at 37 degrees C, Group II - 35% HP; Group III - 35% HP + acidulated fluoride (1.23%) and Group IV - 35% HP + neutral fluoride (2%). The experimental groups received three applications of bleaching gel and after the last application all specimens were polished. This procedure was repeated after 7 and 14 days, and during the intervals of applications, the specimens were stored in artificial saliva at 37 degrees C. Scanning electron microscopy (SEM) analysis showed superficial irregularities and porosities to varying degrees in bleached enamel compared to control group. Sample evaluation was made by attributing scores, and data were statistically analyzed using Kruskal-Wallis and Dunn tests (P < 0.05). SEM qualitative investigation demonstrated that 35% hydrogen peroxide affected human dental enamel morphology, producing porosities, depressions, and superficial irregularities at various degrees. These morphological changes were higher after the application of 1.23% acidulated fluoride gel. Microsc. Res. Tech. 74:512-516, 2011. (C) 2010 Wiley-Liss, Inc.

Assessment of the Availability of Bone Volume for Grafting in the Donor Retromolar Region Using Computed Tomography: A Pilot Study

Purpose: The purpose of this study was to evaluate the area and volume of bone available for grafting in a donor retromolar region using computed tomography (CT). Materials and Methods: Ten patients previously scanned by multislice CT were selected for evaluation. Images from partially and completely dentate patients at least 18 years of age were included in the study; those from patients with impacted or erupted third molars or intrabony lesions in the study area were not included. Computer software with appropriate tools was used to handle the images. Two calibrated observers made measurements separately. Safety margins in relation to the lingual cortex, the base of mandible, and the alveolar canal were established in each cross-section of the CTs. Measurements were done by using cross-sectional views, and the results were calculated after three-dimensional reconstruction, providing area and volume data. Results: The mean area of bone available for grafting was 8.12 cm(2) ( range, 0.00 to 13.60 cm(2)) and 8.32 cm(2) ( range, 0.00 to 14.30 cm(2)) for observers 1 and 2, respectively. Mean available bone volume for grafting was 0.79 cm(3) ( range, 0.00 to 1.50 cm(3)) for observer 1 and 0.85 cm(3) ( range, 0.00 to 1.60 cm(3)) for observer 2. Interobserver analysis showed substantial agreement. Conclusion: The retromolar region showed a wide variety of anatomic differences among patients. Three-dimensional multislice CT allows reproducible measurements of the area and volume of the retromolar region. Int J Oral Maxillofac Implants 2010; 25: 374-378

Early dental plaque formation on toothbrushed titanium implant surfaces

Purpose: To evaluate the qualitative and quantitative differences on dental plaque formation on two different roughness titanium implant surfaces, i.e. machined and titanium plasma sprayed, as well as the amount of plaque removal by regular toothbrushing after 72-hour plaque accumulation. Methods: Eight systemically healthy subjects were recruited from the patient pool of a private dental practice. All patients underwent oral hygiene instruction and full mouth prophylaxis. Subsequently, maxillary casts from all patients were obtained and removable 0.7 mm-thick acetate stents without occlusal contact points were fabricated to support four titanium specimens of 4x2x2 mm divided into two groups (machined and plasma sprayed). Subjects were instructed to wear the stents for 72 hours, full time, removing them only during regular oral hygiene. Subsequently, the appliances were immediately repositioned and then the test side was brushed for 20 seconds. At the end of the 72-hour period, the stents were removed and prepared for microbiological analysis. Results: Both machined and plasma sprayed brushed surfaces presented statistically significant fewer bacteria than non-brushed surfaces. Similarly, regarding surface roughness, machined surfaces presented a total number of bacteria significantly smaller than those presented by plasma sprayed surfaces (P< 0.05). Statistically, the non-brushed machined turned surfaces presented a greater amount of Streptoccocus sp. when compared to the brushed machined surfaces. It was concluded that rough surfaces accumulated more dental plaque than polished surfaces. Both brushed surfaces presented less plaque accumulation, however, implant brushing was more effective on machined surfaces. (Am J Dent 2008;21:318-322).

Characterization of dimethacrylate polymeric networks: A study of the crosslinked structure formed by monomers used in dental composites

The resin phase of dental composites is mainly composed of combinations of dimethacrylate comonomers, with final polymeric network structure defined by monomer type/reactivity and degree of conversion. This fundamental study evaluates how increasing concentrations of the flexible triethylene glycol dimethacrylate (TEGDMA) influences void formation in bisphenol A diglycidyl dimethacrylate (BisGMA) co-polymerizations and correlates this aspect of network structure with reaction kinetic parameters and macroscopic volumetric shrinkage. Photopolymerization kinetics was followed in real-time by a near-infrared (NIR) spectroscopic technique, viscosity was assessed with a viscometer, volumetric shrinkage was followed with a linometer, free volume formation was determined by positron annihilation lifetime spectroscopy (PALS) and the sol-gel composition was determined by extraction with dichloromethane followed by (1)H NMR analysis. Results show that, as expected, volumetric shrinkage increases with TEGDMA concentration and monomer conversion. Extraction/(1)H NMR studies show increasing participation of the more flexible TEGDMA towards the limiting stages of conversion/crosslinking development. As the conversion progresses, either based on longer irradiation times or greater TEGDMA concentrations, the network becomes more dense, which is evidenced by the decrease in free volume and weight loss after extraction in these situations. For the same composition (BisGMA/TEGDMA 60-40 mol%) light-cured for increasing periods of time (from 10 to 600 s), free volume decreased and volumetric shrinkage increased, in a linear relationship with conversion. However, the correlation between free volume and macroscopic volumetric shrinkage was shown to be rather complex for variable compositions exposed for the same time (600 s). The addition of TEGDMA decreases free-volume up to 40 mol% (due to increased conversion), but above that concentration, in spite of the increase in conversion/crosslinking, free volume pore size increases due to the high concentration of the more flexible monomer. In those cases, the increase in volumetric shrinkage was due to higher functional group concentration, in spite of the greater free volume. Therefore, through the application of the PALS model, this study elucidates the network formation in dimethacrylates commonly used in dental materials. (C) 2010 Elsevier Ltd. All rights reserved.