Estimation of height and width of bone in anterior hard palate as a donor site for autogenous bone graft using IOPA by long cone paralleling technique.

OBJECTIVE: The purpose of this study was to determine the amount of bone available for harvesting from the anterior palate region using IOPA (Intra Oral Peri Apical) radiographs. MATERIALS AND METHODS: A total of 80 patients visiting the outpatient Department of Periodontics were selected. Two groups of male and female consisting 40 patients each were made. They were further subdivided into two groups based on age, 18-30 and 31-60 years of age, each with twenty patients. The patients were subjected to radiographic examination consisting of IOPA radiographs. All IOPA radiographs were taken using long cone paralleling technique. Availability of bone for harvesting, above the apices of teeth was calculated. RESULTS: The bone available in the incisor region was approximately 6.5 to 6.9 mm in height and 7.4 to 8 mm in width, in canine region 6.35 to 6.65 mm in height and 7.6 to 8.1 mm width, and in the premolar region 3.65 to 3.75 mm in height and width. When the bone height and width were compared gender and age wise for CI (central incisors), LI (lateral incisors), canine and premolars, using Student's t- test the results were not statistically significant. CONCLUSION: For the purpose of harvesting autogenous bone, from the region of incisor and canine approximately 6.35 to 6.9 mm height and 7.4 to 8.1 mm width of bone may be harvested maintaining a safe distance from the apices of the teeth and the nasal floor. The premolar region does appear to yield sufficient bone at safe distances from the maxillary sinus and the apices of the premolars.

Correlation of interdental and interradicular bone loss in patients with chronic periodontitis: a clinical and radiographic study.

OBJECTIVE: The aim of this study was to investigate the correlation between interdental and interradicular bone loss and clinical parameters in patients with chronic periodontitis. MATERIALS AND METHODS: One hundred-twenty intraoral periapical radiographs of first molars were obtained from patients with chronic periodontitis and were digitalized to record height and width of the bone defect in the interdental and interradicular region (furcation) and bone defect angle in the interdental region in vertical defects. Pocket depth (PD) and clinical attachment loss (CAL) was recorded at three sites. The data was divided into groups according to the pocket depth at each site. One-way ANOVA was used to compare three different pocket depths with respect to CAL, height and width at a particular site. This was followed by Tukeys HSD post hoc tests to know the significant difference between two groups of pocket depths. Lastly Karl Pearsson's co-efficient method was applied to find out the relationship among CAL, height and width for the particular site. RESULTS: When the pocket depth groups were compared for CAL, height and width of the defect at all three maxillary and mandibular sites, the results were statistically significant. In maxillary molars, a radiographic bone defect height ranging from 3.4-7.1 mm at the mesiobuccal site and 3.6-7.2 mm at the distobuccal site was associated with 1.2-3.5 mm defect height in the interdental region. In mandibular molars, a radiographic bone defect height ranging from 2.9-7.0 mm at the mesiobuccal site and 3.2-6.8 mm at the distobuccal site was associated with 1.2-3.6 mm defect height in the interdental region. The mean bone defect angle was 36.3 ± 16.5 degrees. CONCLUSION: Treatment of interdental bone loss can prevent further bone loss in the interradicular region. Radiographic measurements combined with clinical findings can be useful for periodontal risk assessment.

Evaluation of design parameters of eight dental implant designs: a two-dimensional finite element analysis.

AIM: Implants could be considered predictable tools for replacing missing teeth or teeth that are irrational to treat. Implant macrodesign includes thread, body shape and thread design. Implant threads should be designed to maximize the delivery of optimal favorable stresses. The aim of this finite element model study was to determine stresses and strains in bone by using various dental implant thread designs. MATERIALS AND METHODS: A two-dimensional finite element model of an implant-bone system is developed by using Ansys. An oblique load of 100 N 45° to the vertical axis of implant as well as a vertical load was considered in the analyses. The study evaluated eight types of different thread designs to evaluate stresses and strains around the implants placed in D1 bone quality. RESULTS: Forty-five-degree oblique von Mises stresses and strains were the highest for the filleted and rounded square thread with an angulation of 30° (216.70 MPa and 0.0165, respectively) and the lowest for the trapezoidal thread (144.39 MPa and 0.0015, respectively). CONCLUSIONS: The findings in this study suggest that the filleted and rounded square thread with an angulation of 30° showed highest stresses and strains at the implant-bone interface. The trapezoidal thread transmitted least amount of stresses and strains to the cortical bone than did other models.

Toll-like receptor 2 expression in refractory periapical lesions.

AIM: To investigate the expression of TLR2 in refractory periapical lesions. METHODOLOGY: Refractory periapical lesion biopsies were histopathologically and clinically categorized into asymptomatic periapical granuloma (n=10), symptomatic periapical granuloma (n=10) or periapical cyst (n=10) and prepared for immunohistochemical staining using antibodies to TLR2, CD3 and CD19 or staining with methyl green pyronin. Sections were viewed under light microscopy and the presence or absence of the target cells was correlated with the histopathological and clinical data. Additionally, TLR2 expression was quantified by counting TLR(+) cells. RESULTS: Various mononuclear inflammatory cells in the bacteria-induced periapical lesions were reactive to TLR2 antibody, with many showing morphological similarities to lymphocytes and plasma cells. Lymphocytes were the most numerous cells in the inflammatory infiltrate. In refractory periapical granuloma, CD3(+) T cells were more numerous, whereas in periapical cysts, CD19(+) B cells were more numerous. There was a statistically significant (P<0.05) higher expression of TLR2 in symptomatic periapical granuloma than asymptomatic periapical granuloma or periapical cyst. CONCLUSION: The presence of TLR-expressing cells in periapical granulomas and cysts provides further evidence that periapical cysts are likely to be sustained by the immune system via reaction to bacterial antigens.

Antigen recognition and presentation in periapical tissues: a role for TLR expressing cells?

Bacteria are the prime cause of periapical diseases and root canal microbiology is a well-researched area of endodontics. Antigen-presenting cells (APCs) are present in periapical lesions of endodontic origin and play a substantial role in recognizing, processing and presenting pathogenic antigens to the adaptive immune system such as an effective and long-lasting immune response is generated against the specific pathogens. Toll-like receptors (TLRs) are germ-line encoded pathogen recognition receptors (PRR) expressed by various APCs which induce their maturation, lead to gene transcription in the nucleus and the production of several pro- and anti-inflammatory cytokines. Thirteen TLRs have been discovered, 10 of which have been identified in humans so far. Preliminary studies of dental pulp tissue have demonstrated various cell types expressing different TLRs in response to commonly encountered microorganisms. However, there is little information available regarding the expression and function of the various TLRs in human periapical lesions. This review discusses the interactions of various APCs in periapical lesions and the possible roles of different TLRs and APCs in pulp/periapical pathogen recognition and presentation to the adaptive immune system in the initiation and sustaining of periapical diseases.

Acutely sodded expanded polytetrafluoroethylene grafts produce only prostacyclin: a qualitative difference from saphenous veins.

Select subsets of patients require prosthetic graft material for revascularization. Although arterial prosthetic grafts of large caliber perform acceptably, grafts of <6 mm exhibit a high attrition rate. Microvessel endothelial sodding, a method resulting in the lining of prosthetic grafts with autologous endothelium, improves graft patency; however, aggressive antiplatelet therapy is still required, because terminating an antiplatelet regimen accelerates graft attrition. The present investigation was designed to address the acute production of vasoactive substances in microvessel endothelial cell sodded expanded polytetrafluoroethylene (ePTFE) grafts in an attempt to delineate a possible mechanism behind the continued requirement for antiplatelet therapy. Equal lengths of acutely sodded ePTFE grafts (canine falciform ligament source) and saphenous veins (SV) (canine source) were evaluated by superfusion bioassay. Basal secretion from ePTFE grafts relaxed the biodetector ring 1 +/- 3%, whereas SV relaxed the ring 10 +/- 3% (p < 0.05, ePTFE vs. SV). Relaxation with acetylcholine stimulation was 49 +/- 7% in grafts and 50 +/- 10% in veins (p = NS). Calcium ionophore stimulation produced relaxation of 37 +/- 9% from ePTFE grafts and 100 +/- 23% from SV (p < 0.05). Indomethacin added to perfusate reduced relaxations from sodded ePTFE grafts to 20.2 +/- 9.2% with acetylcholine stimulation and 12.5 +/- 4.3% with calcium ionophore (p < 0.05 vs. control); addition of N(G)-monomethyl-L-arginine (L-NMMA) had no effect on the release of vasoactive substances from ePTFE grafts. In contrast, relaxations of effluent from SV stimulated by acetylcholine and calcium ionophore were significantly attenuated with indomethacin and L-NMMA (p < 0.05 vs. control). Scanning electron microscopy demonstrated confluent endothelium in SV and a nonconfluent endothelial cell layer in grafts. Acutely sodded ePTFE grafts produce vasoactive substances that quantitatively and qualitatively differ from those produced by canine SV. The ePTFE grafts produce mainly prostanoids, whereas SV produce both nitric oxide and prostanoids. The endothelial cell isolation procedure and absence of immediate graft luminal confluence may contribute to the observed differences.

Kinetics and active fraction determination of a protease enzyme immobilized on functionalized membranes: mathematical modeling and experimental results.

A detailed study on the performance of a membrane bioreactor is presented, considering diffusion reaction models with product adsorption and structure-function correlations. The enzyme papain was utilized for experimental investigation both in the homogeneous state and on a modified polysulfone (MPS) membrane. Variation of enzyme loading on the membrane and enzyme concentration in the solution state depicted decreasing activity with increasing loading. The performance of the bioreactor was simulated using a diffusion reaction model within a recirculation loop. Electron paramagnetic resonance (EPR) spectroscopy was utilized to study the conformational changes of the active site of papain immobilized on the MPS membrane. Two models were applied to correlate the structure and function of the biocatalyst, based on loading (kinetics) and EPR (structure). The active fractions, lambda, determined from the two models were 0.29 and in the range 0.25-0.3, respectively. The intrinsic kinetics (Vmax) for the immobilized enzyme as determined by the correlations were in the range 101-121 micromol/(g.min), compared to 111 micromol/(g.min) for the homogeneous enzyme. This proves that the immobilized enzyme kinetics do approach homogeneous kinetics for papain on the MPS membrane, when corrected for adsorption and conformational changes.

Evaluation of pluronic F127-based sustained-release ocular delivery systems for pilocarpine using the albino rabbit eye model.

The overall objective of this study was to develop Pluronic F127 (PF127)-containing formulations of pilocarpine hydrochloride (PHCL) which can be used for sustained-release ocular delivery of PHCL. The PF127 formulations of PHCL containing methylcellulose (MC) or hydroxypropyl methylcellulose (HPMC) as an additive had previously exhibited the slowest dissolution rates and released the drug the slowest in vitro. This study was performed to assess the in vivo performance of these two formulations using miosis in the albino rabbit eye produced by PHCL as a measure of ocular bioavailability. The PF127MC formulation (20 microL) had a significantly greater intensity of miosis compared to the same volume of an isotonic solution of PHCL. The duration and the intensity of the miotic response increased significantly as the instilled volume of the PF127MC gel formulation increased. The miotic response, expressed as % bioactivity by assigning a value of 100% to the 20 microL PF127MC treatment, was increased as the volume instilled was reduced from 60 to 20 microL. However, no difference in bioactivity between the 60 and 100 microL volumes was observed. In addition, the 100 microL volumes of both the PF127MC and PF127HPMC gel formulations exhibited bioactivity equivalent to 20 microL of an isotonic PHCL solution. Thus, for a given instilled concentration, the larger the volume instilled the greater the amount of drug present in tear fluid and thus the higher the concentration delivered to the iris sphincter muscle and hence the greater the miotic response. However, the fraction of the dose reaching the iris sphincter muscle was greater for the smaller instilled volume. On the basis of these findings and previous in vitro results, the PF127 formulations of PHCL having MC or HPMC as an additive showed considerable potential as sustained-release ocular delivery systems for PHCL. This conclusion was based upon their ability to provide a substantial prolongation of drug action and an improvement in the ocular bioavailability of pilocarpine compared to conventional eye drops and previously utilized PF127 formulations of PHCL. It appears that ocular bioavailability can be increased more readily by altering both the rheological characteristics of the delivery system and by using a smaller dose volume.

In vitro evaluation of pluronic F127-based controlled-release ocular delivery systems for pilocarpine.

The overall objective of this study was to develop pluronic F127 (PF127)-containing formulations of pilocarpine hydrochloride (PHCL) suitable for controlled-release ocular delivery of PHCL. Various aqueous formulations were evaluated containing 1% w/v PHCL and 25% w/v PF127 alone or with one of the following additives present: poly(ethylene glycol) 4600 (PEG), poly(vinylpyrrolidone) 10,000 (PVP), poly(vinyl alcohol) 10,000 (PVA), methylcellulose 15 cP (MC), and hydroxypropyl methylcellulose 80-120 cP (HPMC). The in vitro dissolution of the PF127 formulations and the pilocarpine release profiles from them were obtained simultaneously at 34 degrees C and room temperature using a membraneless in vitro model. It was observed that the PEG- and PVP-containing PF127 formulations of PHCL dissolved the quickest and released the drug at a significantly faster rate than the control PF127 formulation, which had no additive present. The PF127 formulations of PHCL containing MC or HPMC exhibited the slowest dissolution rates and released the drug the slowest. The same rank order was observed at each temperature for the dissolution and PHCL release profiles of each formulation. On the basis of the in vitro results, the PF127 formulations of PHCL containing MC or HPMC as an additive showed potential for use as controlled-release ocular delivery systems for PHCL.

Seropositivity, adenoid hypertrophy, and secretory otitis media in adults--a recognized clinical entity.

Otolaryngologic manifestations of AIDS have been described in the past. In this study, I had examined 14 adults with nasal obstruction and mouth breathing. Nine patients also reported deafness--unilateral in three of them and bilateral in six. All of them revealed a mass in the nasopharynx, either on the posterior rhinoscopy or the x-ray neck-lateral view. To exclude nasopharyngeal malignancy, all of the patients underwent examination of the nasopharynx while under general anaesthesia and biopsy. The histopathologic diagnosis in every patient was nonspecific, reactive lymphoid hyperplasia, which has been described in the background of HIV infections. Four were already confirmed HIV-positive and 10 were found positive on the HIV antibody test. A strong association was established between seropositivity, adenoid hypertrophy, and secretory otitis media in adults.

Down syndrome: a review of the literature.

This review of the literature on Down syndrome focuses on various systemic anomalies and oral anomalies, its clinical manifestations, and recommendations for persons with Down syndrome. From the time Down syndrome was diagnosed by phenotype to the present when karyotyping distinguishes chromosomal subgroups, increasingly sophisticated tests and treatments have influenced the lives of Down syndrome patients. Medical advances, special educational programs, and increasing social acceptance of disabled people in the community have resulted in current trends of normalization and deinstitutionalization of these patients. Once a dentist is familiar with a patient's medical history and takes needed precautions, these patients can be treated routinely in a dental office.

Pluronic F127-based ocular delivery system containing biodegradable polyisobutylcyanoacrylate nanocapsules of pilocarpine.

The objectives of our study were to prepare a biodegradable polyisobutylcyanoacrylate (PIBCA) colloidal particulate system of pilocarpine, to incorporate it into a Pluronic F127(PF127)-based gel delivery system, and to evaluate its ability to prolong the release of pilocarpine. Polyisobutylcyanoacrylate nanocapsules (PIBCA-NC) of pilocarpine were prepared by interfacial polymerization. Physicochemical characterization of the colloidal dispersion of PIBCA-NC of pilocarpine was performed by measuring drug loading, particle size analysis, and scanning electron microscopy. Results indicated that approximately 13.5% of pilocarpine was loaded onto the PIBCA-NC, the nanocapsules ranged from 370 to 460 nm, the distribution was narrow, and there was no significant effect of stirring speed on particle size. The PIBCA-NC dispersion of 1% pilocarpine alone (I) and after incorporation into the Pluronic F127 gel delivery system (II) were compared against 1% pilocarpine incorporated into a PF127 gel containing 5% methylcellulose (PF127MC) alone (III) by measuring the miotic response in the albino rabbit eye. Statistical analysis indicated a rank-order for both the duration and intensity of miosis of II > III >> I, with all differences being significant (p < 0.05). Thus, it appears that II increases the contact time of pilocarpine with the absorbing tissue in the eye, thereby improving ocular bioavailability. The PIBCA-NC of pilocarpine dispersed in the PF127MC gel delivery system has considerable potential for achieving a prolonged delivery for such drugs as pilocarpine and other more hydrophobic drugs.

Orthodontic considerations in individuals with Down syndrome: a case report.

The skeletal and soft tissue features, aberrations in dental development, and periodontal and caries characteristics of Down syndrome related to orthodontic treatment are discussed. A case report describing the successful orthodontic treatment of a 13-year-old boy with Down syndrome and a severe malocclusion is presented.

Extraction of p-coumaric acid and ferulic acid using surfactant-based aqueous two-phase system.

Ferulic acid (FA) and p-coumaric acid (pCA) are high-value products that can be obtained by alkaline hydrolysis of lignocellulose. Present work explores the potential of surfactant-based cloud-point extraction (CPE) for FA and pCA extraction from corn cob hydrolysate. More than 90 % (w/w) extraction of both FA and pCA was achieved from model system with L92. The partition coefficient of FA and pCA in L92 aqueous phase system was 35 and 55, respectively. A significant enrichment (8-10-fold) of both FA and pCA was achieved in surfactant-rich phase. Furthermore, the downstream process volume was reduced by 10 to 13 times. Optimized conditions (5 % v/v L92 and pH 3.0) resulted into 85 and 89 % extraction of FA and p-CA, respectively, from alkaline corn cob hydrolysate. Biocompatibility tests were carried out for L92 for ethanol fermentation and found to be biocompatible. Thus, the new surfactant-based CPE system not only concentrated FA and pCA but also reduced the process volume significantly. Further, aqueous phase containing sugars can be used for ethanol fermentation.

A clinicopathologic analysis of 88 lung resections of suspected metastatic carcinomas with proven primaries.

BACKGROUND: The lung is the most common site for metastatic carcinomas. Very few studies have comprehensively analyzed all pulmonary resections for metastatic carcinomas. AIMS AND OBJECTIVES: To analyze all lung resections for suspected metastatic carcinomas accrued over 10 years to evaluate: (i). The most frequent primary site,(ii). The interval between primary tumor diagnosis and lung metastases, and (iii). The proportion of inadvertently resected benign lesions, clinicoradiologically mistaken for metastatic deposits. MATERIALS AND METHODS: Between 2002 and 2011, 88 pulmonary metastasectomies were done for suspected metastatic carcinomas, which form the basis of this study. RESULTS: In 81 of 88 cases (92%) the diagnosis of metastatic carcinoma was histologically confirmed, whereas 7 cases (8%) were non-neoplastic. The mean interval between primary tumor and metastases was 2.5 years. The primary sites were colorectum (30; 37%), kidney and breast (14; 17.3% each), cervix (9; 10%), salivary gland carcinoma (3), thyroid carcinoma (2), squamous carcinoma (2, one each of mandible and larynx), papillary urothelial carcinoma (2), hepatocellular carcinoma (1), endometrioid adenocarcinoma (1), carcinosarcoma of endometrium (1), adrenocortical carcinoma (1), and neuroendocrine carcinoma (1). The 7 non-neoplastic lesions (8%) histologically revealed tuberculosis (4), bronchopneumonia (2), and aspergillosis (1). CONCLUSIONS: Almost three fourths (71.6%) of the metastatic pulmonary resections comprised primaries from colorectum, breast and kidney. The interval between primary tumor and metastases ranged from zero months to 10 years (mean 2.5 years). Tuberculosis was the most common histologic diagnosis among the 8% of the non-neoplastic lesions, which were mistaken for metastatic carcinoma on clinical evaluation.

Histologic evaluation of absorbable and non-absorbable barrier coated mesh secured to the peritoneum with fibrin sealant in a New Zealand white rabbit model.

PURPOSE: The purpose of this study is to evaluate the histologic response to fibrin sealant (FS) as an alternative fixation method for laparoscopic ventral hernia repair. METHODS: One non-absorbable barrier mesh (Composix™) and three absorbable barrier meshes (Sepramesh™, Proceed™, and Parietex™ Composite) were used for the study, with uncoated macroporous polypropylene mesh (ProLite Ultra™) as the control. Three methods of fixation were used: #0-polypropylene suture + FS (ARTISS™, Baxter Healthcare Corp.), FS alone (ARTISS™), or tacks alone (n = 10 for each group). Two pieces of mesh (of dimensions 4 × 4-cm) were secured intraperitoneally in 75 New Zealand white rabbits. After 8 weeks, hematoxylin and eosin (H&E)-stained specimens were evaluated for host tissue response. Statistical significance (P < 0.05) was determined using a one-way analysis of variance (ANOVA) with Fisher's least significant difference (LSD) post hoc test. RESULTS: Composix™ with FS only showed significantly greater cellular infiltration than with suture + FS (P = 0.0007), Proceed™ with FS only had significantly greater neovascularization than with suture + FS (P = 0.0172), and ProLite Ultra™ with suture + FS had significantly greater neovascularization than with tacks only (P = 0.046). Differences due to mesh type showed that Composix™ exhibited less extensive cellular infiltration (P ≤ 0.0032), extracellular matrix (ECM) deposition, and neovascularization, and demonstrated less inflammatory cells and more fibroblasts compared to the other meshes (P < 0.05). CONCLUSIONS: FS did not have a significant histologic effect compared to tacks when utilized for the fixation of mesh to the peritoneum of New Zealand White rabbits. However, the mesh type did have a significant histologic effect. The permanent barrier mesh (Composix™) was associated with less histologic incorporation than absorbable barrier and macroporous meshes, as evidenced by lower levels of cellular infiltration, ECM deposition, and neovascularization, independent of the fixation method used.