Membrane barriers for guided bone regeneration: An overview of available biomaterials

Dental implants revolutionized the treatment options for restoring form, function, and esthetics when one or more teeth are missing. At sites of insufficient bone, guided bone regeneration (GBR) is performed either prior to or in conjunction with implant placement to achieve a three-dimensional prosthetic-driven implant position. To date, GBR is well documented, widely used, and constitutes a predictable and successful approach for lateral and vertical bone augmentation of atrophic ridges. Evidence suggests that the use of barrier membranes maintains the major biological principles of GBR. Since the material used to construct barrier membranes ultimately dictates its characteristics and its ability to maintain the biological principles of GBR, several materials have been used over time. This review, summarizes the evolution of barrier membranes, focusing on the characteristics, advantages, and disadvantages of available occlusive barrier membranes and presents results of updated meta-analyses focusing on the effects of these membranes on the overall outcome.

Radial shortening osteotomy vs partial capitate shortening osteotomy in Kienböck's disease: Medium-term radiological and clinical results

This study aimed to compare medium-term results for partial capitate shortening (PCS) and radial shortening (RS) osteotomies on lunate bone revascularization and disease progression in patients with stage II or IIIA Kienböck's disease. Patients who underwent surgery for Kienböck's disease between March 2010 and July 2020 were retrospectively evaluated. Clinical evaluation included assessment of pain, joint range of motion, strength, DASH, visual analog scale (VAS) for pain, Modified Mayo Wrist Score (MMWS), satisfaction and time to return to work, with comparison as appropriate to the contralateral side. Preoperative and postoperative plain radiographs and magnetic resonance imaging (MRI) were used for radiological evaluation. Lichtman staging and signal changes in the lunate were evaluated using MRI. Group 1 (PCS) included 14 patients and Group 2 (RS) 14. Mean follow-up was 57.8 months (range 24-102) in Group 1 and 49.4 months (range 36-73) in Group 2. Clinical evaluation included pain on VAS, DASH score, MMWS, range of motion, and grip, palmar and key pinch strength. Regarding lunate bone vascularization, increased signal on final follow-up MRI was observed in 10 of the 14 patients in Group 1 and 7 of the 14 patients in Group 2. There was a positive correlation between revascularization and final follow-up MMWS (p = 0.006). The present study thus showed that functional scores were improved by revascularization in Kienböck's disease. Both osteotomies had clinically and radiologically satisfactory results. However, we believe that PCS osteotomy is preferable, as it leads to higher revascularization rates without increasing ulnolunate load.

Are radiological measurements reliable methods in the postoperative follow-up of calcaneal fractures?

Background

Böhler's angle (BA) and the crucial angle of Gissane (CAG) are the most frequently used objective measurements for the follow-up of fixation following calcaneus fracture surgery. However, the measurements of these angles by different people can affect the results and cause conflicting interpretations of different results obtained. This has caused confusion in the literature.

Aims

The aim of this study was to investigate the reliability and disagreement of BA and the CAG, and to interrogate the veracity of angular changes in the postoperative period of calcaneal fractures.

Methods

In the first round, a total of 82 postoperative lateral radiographs were investigated to assess the inter-tester reliability and disagreement. Second round; all radiographs were re-evaluated by two testers 15 days after the first measurement. These values were used to assess the intra and inter-tester reliability, disagreement and false negative/positive angular change. All measurements were performed separately by a radiologist and an orthopedic surgeon.

Results

Inter- and intra-tester reliability was found low to high in BA (ICC: 0.465 to 0.837), and moderate to very high in CAG (ICC: 0.661 to 0.926). The mean inter-tester disagreement of BA was 4.19° and 6.07°. These values were 4.76° and 7.22° for CAG. The mean intra-tester disagreement of BA was 4.09° for the orthopedic surgeon and 3.97° for the radiologist. These values were 4.96° and 4.39° for CAG respectively. The false negative angular difference was found for BA in 51 (62.2%) cases for the orthopedic surgeon and 46 (56.1%) cases for the radiologist. The mean values were -3.87° and -4.21°, respectively. For the CAG, the false positive angular difference was found in 43 (52.4%) cases for both the orthopedic surgeon and the radiologist. The mean values were +5.01° and +4.72°, respectively.

Conclusion

These angles alone should not be considered to be of guidance in the postoperative period. If any angular change is determined on the lateral radiographs, this could arise from a disagreement or false angular change.

Salivary concentrations of macrophage activation-related chemokines are influenced by non-surgical periodontal treatment: a 12-week follow-up study

Background: During periodontal inflammation, bacteria induces chemokine expression and migration of various inflammatory cells. The aim of the study was to learn if periodontal treatment alters salivary concentrations of macrophage activation-related chemokines and if such alterations correlate with abundance of periodontitis-associated bacteria.

Methods: Twenty-five patients with periodontitis completed the study (NCT02913248 at clinicaltrials.gov). Periodontal parameters and stimulated saliva samples were obtained at baseline and 2, 6 and 12 weeks after non-surgical periodontal treatment. Salivary concentrations of monocyte chemoattractant proteins (MCP-1-4), macrophage-derived chemokine (MDC), macrophage migration inhibitory factor (MIF), monokine induced by interferon-gamma (MIG), macrophage inflammatory protein (MIP-1α) and interferon-inducible protein (IP-10) were quantified using the Luminex® xMAP™ technique and abundance of bacteria was quantified using next-generation sequencing.

Results: The treatment improved all periodontal parameters and caused an increase in the concentrations of MCP-2, MDC and MIP-1α at week 12 compared to baseline, week 2 and week 6, respectively. Salivary concentrations of MCP-1-2, MDC, MIG, MIP-1α and IP-10 correlated with the abundance of specific periodontitis-associated bacteria.

Conclusions: Periodontal treatment impacts salivary concentrations of MCP-2, MDC and MIP-1α, which correlate with the abundance of specific periodontitis-associated bacteria. This indicates that these chemokines reflect periodontal status and possess potential in illustrating a response to treatment.

Anatomic variations associated with antrochoanal polyps

Objective

Although more than a century has passed since antrochoanal polyps (ACPs) were first defined, etiopathogenesis still remains unclear. The aim of this study was to investigate the relationship between ACPs and sinonasal cavity variations.

Subjects and Methods

One hundred and forty-four patients with ACP on paranasal sinus computed tomography scans (ACP group) and 160 paranasal sinuses without ACP (control group) were included into the study. The study group was evaluated in respect of the presence of retention cyst in the contralateral maxillary sinus and sinus bone wall sclerosis thickening. Both groups were also compared with respect to the frequency of sinonasal anatomic variations, nasal septal deviation, variations of the uncinate process insertion, concha bullosa, paradoxical middle turbinate, and accessory maxillary sinus ostium. In the ACP group, the cases with septal deviation (SD) were also evaluated whether the deviation convexity was towards the polyp side or the opposite side. In addition, the posterior extension of ACPs were evaluated in three groups as middle meatus, nasopharynx, and oropharynx extension.

Results

The prevalence of retention cyst, sinus wall sclerosis thickening, SD, and accessory maxillary ostium was significantly higher in the ACP group. A negative directional correlation was determined between the SD side and ACP side. When the ACP extensions were examined, middle meatus extension was seen in 32.6%, nasopharynx in 56.3%, and oropharynx in 11.1%.

Conclusion

Accessory ostium may be an accelerating factor in the transformation of retention cyst to ACP. Furthermore, the changes in the nasal passage airflow on the opposite side suggest that SD contributes to this process.

Construction and characterization of a multilayered gingival keratinocyte culture model: the TURK-U model

In construction of epithelial cells as multilayers, the cells are grown submerged to confluence on fibroblast-embedded collagen gels and, then, lifted to air to promote their stratification. We recently demonstrated that gingival epithelial cells form uniform monolayers on semi-permeable nitrocellulose membranes, supported with a semi-solid growth medium, which allows the cells to grow at an air-liquid-solid interface from the beginning of the culturing protocol. In this study, the aim was to further develop our previous model to form a multilayered gingival epithelial culture model. Two different epithelial cell lines (HaCaT from skin and HMK from gingiva) were used in all experiments. Both cell lines were grown first as monolayers for 3 days. After that, keratinocytes were trypsinized, counted and seeded on a sterile semi-permeable nitrocellulose membrane placed on the top of a semi-solid growth medium, forming an air-liquid-solid interface for the cells to grow. At days 1, 4, and 7, epithelial cells were fixed, embedded in paraffin, and sectioned for routine Hematoxylin-Eosin staining and immunohistochemistry for cytokeratin (Ck). At day 1, HMK cells grew as monolayers, while HaCaT cells stratified forming an epithelium with two to three layers. At day 4, a stratified epithelium in the HMK model had four to five layers and its proliferation continued up to day 7. HaCaT cells formed a dense and weakly proliferating epithelium with three to four layers of stratification at day 4 but the proliferation disappeared at day 7. At all days, both models were strongly positive for Ck5, Ck7, and Ck 19, and weakly positive for Ck10. Gingival epithelial cells stratify successfully on semi-permeable nitrocellulose membranes, supported with a semi-solid growth medium. This technique allows researchers to construct uniform gingival epithelial cell multilayers at an air-liquid-solid interface, without using collagen gels, resulting in a more reproducible method.

Bioinformatical and in vitro approaches to essential oil-induced matrix metalloproteinase inhibition

CONTEXT

Essential oils carry diverse antimicrobial and anti-enzymatic properties.

OBJECTIVE

Matrix metalloproteinase (MMP) inhibition characteristics of Salvia fruticosa Miller (Labiatae), Myrtus communis Linnaeus (Myrtaceae), Juniperus communis Linnaeus (Cupressaceae), and Lavandula stoechas Linnaeus (Labiatae) essential oils were evaluated.

MATERIALS AND METHODS

Chemical compositions of the essential oils were analyzed by gas chromatography-mass spectrometry (GC-MS). Bioinformatical database analysis was performed by STRING 9.0 and STITCH 2.0 databases, and ViaComplex software. Antibacterial activity of essential oils against periodontopathogens was tested by the disc diffusion assay and the agar dilution method. Cellular proliferation and cytotoxicity were determined by commercial kits. MMP-2 and MMP-9 activities were measured by zymography.

RESULTS

Bioinformatical database analyses, under a score of 0.4 (medium) and a prior correction of 0.0, gave rise to a model of protein (MMPs and tissue inhibitors of metalloproteinases) vs. chemical (essential oil components) interaction network; where MMPs and essential oil components interconnected through interaction with hydroxyl radicals, molecular oxygen, and hydrogen peroxide. Components from L. stoechas potentially displayed a higher grade of interaction with MMP-2 and -9. Although antibacterial and growth inhibitory effects of essential oils on the tested periodontopathogens were limited, all of them inhibited MMP-2 in vitro at concentrations of 1 and 5 µL/mL. Moreover, same concentrations of M. communis and L. stoechas also inhibited MMP-9. MMP-inhibiting concentrations of essential oils were not cytotoxic against keratinocytes.

DISCUSSION AND CONCLUSION

We propose essential oils of being useful therapeutic agents as MMP inhibitors through a mechanism possibly based on their antioxidant potential.

Agronomic importance of first development of chickpea (Cicer arietinum L.) under semi-arid conditions: II. Seed imbibition

Due to the slowness growth and weakness of the first developments of chickpea (Cicer arietinum L.), it could not combated with weeds and easily caught up by Ascochyta blight (Ascochyta rabiei (Pass) Labr.) disease. Additionally, due to biotic and abiotic stress factors, esp. at the late sowing, important seed yield losses could be happened. To be able to avoid from them is only possible to accelerate of its first development as possible as. So, one of the best solutions to is to use chemical compounds such as Humic Acid (HA) known soil regulator under the semi-arid conditions. With this aim this research was performed in a Randomized Complete Block Design (RCBD) with four replications under semi-arid field conditions during (2008/2009) and (2009/2010) in Turkiye. Two cultivars (V1 = Gokce and V2 = Ispanyol) and four seed imbibition methods (A0 = 0, A1 = Tap Water, A2 = 1/2 Tap Water + 1/2 Humic acid (HA), A3 = Full HA, as w/w) and seven yield components Plant Height (PH), Number of Branches per Plant (NBP), Number of Pods per Plant (NPP), First Pod Height (NFP), Number of Seeds per Pod (NSP), Seed Weight per Plant (SWP) and 100-Seed weight (HSW) were investigated. The PH and FPH were affected the A0, the NBP, NPP and NSP were affected the A2 and the SWP and HSW were given the varied but not clear responses according to varieties for all the parameters in A1. The A0 and A1 were encouraged the germination and top soil of the plant but, the A2 to A3 were encouraged root system's development. It was concluded that the A2 is a promising method which makes the maximum and positive effect to the first development of the chickpea agronomy under the semi-arid conditions.

Ocular complications with high-dose interferon alpha in chronic active hepatitis

PURPOSE

Interferon alpha, which is used to treat various systemic disorders, has many reversible side-effects involving various organ systems. In this study, chronic active hepatitis patients undergoing interferon alpha therapy were followed with regard to the ocular side-effects.

METHODS

Thirty-six patients with chronic active hepatitis undergoing subcutaneous interferon alpha therapy for 1 year were enrolled. Complete ocular examination and photographic documentation were performed at baseline of the therapy and monthly thereafter. Fisher's exact chi-squared test and Mann-Whitney U-test were employed in the statistical evaluation of the results.

RESULTS

Trichomegaly was noted in 2 (6%) patients. Fifteen patients (42%) were found to have retinopathy with cotton wool spot formation and splinter haemorrhages.

CONCLUSIONS

These findings emphasise the need to monitor these retinal complications, which may result in loss of vision in patients receiving interferon alpha therapy.

The importance of increasing the number of gastric biopsies in the diagnosis of Helicobacter pylori

BACKGROUND/AIMS

The role of Helicobacter pylori in various gastroduodenal diseases is universally accepted. In this study, we aimed to determine the proper number and sites of the gastric biopsies in order to achieve the highest diagnostic yield through the use of a urease test and histopathology. We also compared the histological findings encountered in patients who had Helicobacter pylori (H. pylori) colonization.

METHODOLOGY

Fifty patients referred for upper gastrointestinal endoscopy for dyspeptic complaints were included in the study. Our mapping protocol included 2 biopsies from antrum and 2 biopsies from corpus. We obtained 2 biopsies from each biopsy site for urease test and histopathological assessment. Golden standard positivity for the presence of H. pylori colonization was defined as concomitantly positive urease test and histologically detected bacteria found at the same biopsy site.

RESULTS

Forty-three patients had H. pylori colonization. Colonization rates of H. pylori, sensitivities of urease testing, and histopathology in 4 biopsy sites were not statistically different. Sensitivity of urease testing was 81.4% for 1 biopsy and 100% for 4 cumulative biopsies. Sensitivities of histological assessment were 93% and 100% for 1 and 4 biopsies, respectively.

CONCLUSIONS

Results of this study suggest that 2 biopsies for urease testing and 1 biopsy for histopathology obtained from the antrum or corpus of the stomach were sufficient to obtain the highest statistically significant diagnostic sensitivity.

Does extracorporeal membrane oxygenation benefit neonates with congenital diaphragmatic hernia? Application of a predictive equation

The overall survival of neonates with congenital diaphragmatic hernia (CDH) remains poor despite the advent of extracorporeal membrane oxygenation (ECMO). Attempts at accurately predicting survival have been largely unsuccessful. The purpose of this study was twofold: (1) to identify independent predictors of survival from a cohort of CDH neonates treated at the authors' institution when ECMO was not available and combine them to form a predictive equation, and (2) to apply the equation prospectively in a cohort of CDH neonates, treated at the same institution when ECMO was available, to determine whether ECMO improves outcome. From the clinical data of 62 CDH neonates treated at the authors' center by the same team of university neonatologists and pediatric surgeons between 1983 and 1993 (before ECMO availability), 15 preoperative and seven operative variables were selected as potential independent predictors. When subjected to multivariate, stepwise logistic regression analysis, four variables were identified as statistically significant (P < .05), independent predictors of survival: (1) ventilatory index (VI), (2) best preoperative PaCO2, (3) birth weight (BW), and (4) Apgar score at 5 minutes. When combined via logistic regression analysis, the following predictive equation was formulated: P (probability of survival to discharge) = [1 + e(x)]-1 where x = 4.9 - 0.68 (Apgar) - 0.0032 (BW) + 0.0063 (VI) + 0.063 (PaCO2). Applying a standard cut-off rate of survival at less than 20%, the equation yielded a sensitivity of 94% and a specificity of 82% in identifying the correct outcome of patients treated with conventional ventilatory management. The overall survival rate was 66%. Since the availability of ECMO at the center, 32 CDH neonates were treated using the same conventional ventilatory treatment and surgical repair by the same university staff. The overall survival rate was 69%. The predictive equation was applied prospectively to all neonates to determine predicted outcome, but was not used to decide the treatment method. Eighteen neonates received conventional therapy alone; 16 of 18 survived (89%). Fifteen of the 16 patients who survived had their outcomes predicted correctly (94%). Fourteen neonates did not respond to conventional therapy and required ECMO; 6 of 14 survived (43%). Six of the eight patients predicted to survive, lived (75%). All six patients predicted to die, died despite the addition of ECMO therapy (100%). The mean hospital cost, per ECMO patient who died, was $277,264.75 +/- $59,500.71 (SE). An odds ratio analysis, using the four independent predictors to standardize for degree of illness, was performed to assess the risk associated with adding ECMO therapy. The result was 1.25 (P = 0.75). Although the cohort was not large enough to eliminate significant beta error, the data strongly suggested no advantage of ECMO. At this center, absolute survival rates for neonates with CDH have not been significantly altered since ECMO has become available (66% v 69%). The authors conclude that the predictive equation remains an accurate measurement of survival at their center even when ECMO is used as a salvage therapy. The method of creating a predictive equation may be applied at any institution to determine the potential outcome of CDH neonates and assess the effect of ECMO, or other salvage therapies, on survival rates.

Importance of diarrhea as a presenting symptom of appendicitis in very young children

BACKGROUND

Appendicitis is an uncommon diagnosis in very young children. It is frequently complicated by delays in diagnosis, perforation, and lengthy hospital stays.

OBJECTIVES

To review our recent experience with appendicitis among children younger than 3 years old, and to identify the independent predictors of a prolonged hospital stay.

METHODS

A retrospective case series review was performed on all children under age 3 who had an appendectomy for appendicitis between January 1983 and February 1994. Multiple regression analysis was used to identify the independent predictors of a prolonged hospital stay.

RESULTS

Sixty-three children were identified. Mean age was 2.2 years (range 11 to 35 months). The mean delay from onset of symptoms to presentation was 4.3 days. Fifty-seven percent were initially misdiagnosed. Diarrhea was reported in 33%. Perforation and/or gangrene were found in 84%. Perforation and/or gangrene at laparotomy and a history of diarrhea at presentation were independent predictors of a prolonged hospital stay.

CONCLUSIONS

Appendicitis in children under 3 years old is characterized by delays in diagnosis and perforation. A history of diarrhea is an important factor that confuses the diagnosis, prolongs the observation period, and delays appropriate therapy.