Tetracycline Hydrochloride Solution Research Articles

Preparation of Bi2MoO6@Diatomite composite and its visible light driven reduction of Cr(VI) and removal of tetracycline hydrochloride

The use of cheap and porous substrates to support visible light photocatalyst is an effective solution to avoid the agglomeration of catalyst. Herein, the Bi2MoO6@Diatomite composite has been prepared through hydrothermal reaction with Bi(NO3)3 and Na2MoO4 as precursors and diatomite as substrate. XRD, SEM, TEM, XPS, and DRS are applied to characterize these composite photocatalysts. The photocatalytic performance of the obtained composites were studied through the Cr(VI) reduction and tetracycline hydrochloride (TC) degradation under visible light irradiation (λ > 400 nm). The photocatalytic experimental results display that the sample with 6% diatomite mass faction (Bi2MoO6@6%DE) has the highest catalytic performance in all materials. In the Cr(VI) solution, the Bi2MoO6@6%DE can reduce 90.1% of Cr(VI) in 60 min, while Bi2MoO6 can only reduce 71.7% of pollutants in the same time. In the TC solution, the Bi2MoO6@6%DE can reduce 74.7% of TC in 120 min, while Bi2MoO6 can only reduce 30.5% of pollutants in the same time. The photocatalytic mechanism was further investigated through the test of active radical capture. The main active radicals in the reduction of Cr(VI) is photogenerated electrons. The ·HO−, ·O2 − and holes (h+) are active free radicals in the removal process of TC, and photogenerated holes (h+) have the greatest influence. This composite has good photocatalytic activity and recyclability, so it has great application potential in waste water treatment.

Heat treatment of polymeric PBAT/PCL membranes containing activated carbon from Brazil nutshell biomass obtained by electrospinning and applied in drug removal

Abstract This work aimed to perform a heat treatment on biodegradable polymeric membranes produced by the electrospinning technique to be used in the retention of residual drugs from water. For this, a blend with a concentration of 20 % (w/v) was produced, composed of 75 % Poly(butylene adipate-co-terephthalate) (PBAT) and 25 % poly (e-caprolactone) (PCL) (w/w), solvated in chloroform (CL) and N,N-dimethylformamide (DMF) in the proportion of 85/15 % (v/v), respectively. A portion of 10 % (w/w) activated carbon from Brazil nut shell biomass (CA-BCB) was incorporated in the polymeric solution, which was subjected to electrospinning to obtain the polymeric membranes. Thermal treatments were then carried out on the surface of the electrospun membranes. The membranes were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD) and membranes surface wettability by contact angle. The results of the micrograph images (SEM) showed that the incorporation of CA-BCB produced fibers with smaller diameters without changing the chemical structure of the polymers, which was confirmed by the FTIR analysis. With the addition of activated carbon, there was an increase in the thermal stability of the material, which was confirmed by TGA analysis. In the permeability tests carried out with distilled water (1290 kg h−1 m-2) and tetracycline hydrochloride solution (TCH), 1220 kg h−1 m-2 with 200 min of operation. A PBAT/PCL membrane retention capacity, with heat treatment and addition of CA-BCB, of approximately 67 % was verified. This result suggests that the membranes produced by electrospinning, together with a heat treatment, can be used to retain emerging pollutants.

Facile synthesis, microstructure, formation mechanism, in vitro biocompatibility, and drug delivery property of novel dendritic TiO2 nanofibers with ultrahigh surface area.

In this study, novel dendritic TiO2 nanofibers (D-Ti NFs) with ultrahigh surface area were for the first time synthesized through in situ hydrothermal treatment of the electrospun TiO2 nanofibers (E-Ti NFs) and their microstructure, formation mechanism, in vitro biocompatibility and drug delivery property were investigated. SEM observations showed that D-Ti NFs had dendritic and fibrous morphology with the controllable diameter of 899±26nm to 1955±64nm. TEM observations showed the individual D-Ti NF was assembled by numerous primary nanowires with the diameter of 7±1nm. XRD pattern showed that the D-Ti NFs displayed the characteristic peaks at 24.1°, 28.1°, and 48.3°, all of which were assigned to hydrogen titanium oxide hydrate. BET measurement indicated that D-Ti NFs had the ultrahigh specific surface area of 213.41m2/g. D-Ti NFs showed good in vitro biocompatibility when exposed to Hela cells. After soaked in solution of tetracycline hydrochloride (TH, one of the representative antibiotics, model drug), D-Ti NFs supported the loading of TH with the loading efficiency of 63.73±4.61%. TH-loaded D-Ti NFs supported a sustained release model for TH when immersed in the phosphate buffer saline. After separately incubated with two representative types of bacteria: Escherichia coli and Staphylococcus aureus, TH-loaded D-Ti NFs showed excellent antibacterial property to inhibit the growth of the bacteria, indicating that the released TH was biologically active.

Enhanced degradation of tetracycline hydrochloride using photocatalysis and sulfate radical-based oxidation processes by Co/BiVO4 composites

The Co/BiVO4 composites were prepared by wet impregnation method and used to combine photocatalysis and sulfate radical-based oxidation processes for degradation of tetracycline hydrochloride. The effect factors including the mass percentage of cobalt and peroxymonosulfate (PMS) concentration were investigated in detail. The tetracycline hydrochloride solution with an initial concentration of 40 mg/L could be completely degraded within only 25 min in Co/BiVO4+Vis + PMS system. By cyclic degradation experiment, as-prepared Co/BiVO4 composites had good reusability and stability. Free radicals quenching experiment indicated that SO4− and OH played an important role for degradation of tetracycline hydrochloride. We confirmed the redox cycle of Co2+/Co3+ during the PMS activation process by X-ray photoelectron spectroscopy. Based on the above results, a possible enhanced reaction mechanism was proposed.

In-situ synthesis of mixed phase electrospun TiO2 nanofibers: a novel visible light photocatalyst

TiO2 nanofibers were synthesized by electrospinning method using mixed titanum isopropoxide and polyvinylpyrrolidone precursors in ethanol followed by calcination at high temperature. The obtained TiO2 e-spun nanofibers were characterized by FESEM, TEM, XRD, XPS and BET surface area analytical techniques. XRD result shows that the nanofibers contain both anatase and rutile mixed phases. FESEM and TEM study indicates the development of precise fine tiny nanoparticles with diameter in the range of 10–20 nm, which are oriented along one dimensional direction to form the fibrous structure with diameter in the range of 300–500 nm. The mixed phase TiO2 nanofibers were used as photocatalysts for degradation of Rhodamine-B and Methyl orange under solar light irradiation and also under visible light irradiation. More than 99% degradation was achieved within 90 min of irradiation time for both the dyes. Furthermore, it is observed that the TiO2 photocatalyst is efficiently degrading (98%) the tetracycline hydrochloride solution within 70 min of contact time. The excellent visible light photocatalytic activity may be attributed to the combine factors of hetero-conjunction at anatase–rutile interface and immediate charge transfer due to 1D structure, which inhibit the electron–hole recombination. Rutile-Anatase dual phase TiO2 nanofibers exhibit excellent visible light photocatalytic activity due to the combine factors of hetero-conjunction at anatase-rutile interface and immediate charge transfer due to 1D structure, which inhibits the electron-hole recombination.

Synthesis and Drug Delivery Property of the Magnetic Fe3O4@Silica Nanotubes

In this study, Fe3O4@silica nanotubes (Fe3O4@SiNTs) were synthesized through a co-axial electrospinning of a shell-liquid consisting of tetraethoxysilane, polyvinyl pyrrolidone, ethanol and hydrogen chloride and Fe3O4 nanoparticles (NPs) and a core-liquid of paraffin. Their microstructure and drug delivery property were evaluated. SEM observations showed that Fe3O4@SiNTs had the tubular hollow structure. The presence of magnetic component caused a magnetic separability of Fe3O4@SiNTs. After soaked in the solution of tetracycline hydrochloride (TH, one of the representative antibiotics), Fe3O4@SiNTs supported the adsorption of TH with the loading efficiency of 64±5% to produce TH-loaded Fe3O4@SiNTs. TH-loaded Fe3O4@SiNTs presented a sustained release behavior for TH after soaked in the phosphate buffer saline. After incubation with Escherichia coli (E. coli, one of the most widely used bacteria), TH-loaded Fe3O4@SiNTs exhibited strong anti-bacterial property to inhibit the growth of E. coli, indicating that the released TH was biologically active.

Clinical and radiographic outcomes of a surgical reconstructive approach in the treatment of peri-implantitis lesions: A 5-year prospective case series.

The aim of this study was to evaluate the 5-year clinical and radiographic outcomes following reconstructive therapy of peri-implantitis lesions using mineralized dehydrated bone allograft and resorbable membrane in the nonsubmerged mode of wound healing. Thirty-four patients with at least one implant diagnosed with peri-implantitis were treated by mechanical debridement; chemical decontamination using hydrogen peroxide (3%), chlorhexidine (0.2%), and a tetracycline hydrochloride solution; and bone defect filling with mineralized dehydrated bone allograft and resorbable membrane. Clinical and radiographic assessments were obtained during 5-year follow-up. The primary outcome was the absence of additional marginal peri-implant bone loss ≥1.0mm after surgery, and the composite outcome included the additional marginal peri-implant bone loss, absence of probing depth (PD) ≥5mm, and absence of bleeding on probing (BoP)/suppuration. According to the primary and composite outcomes, the success rate of 34 implants included in the study was 100% and 91% (N=31), at 1year after surgery, and decreased progressively to 77% (N=26) and to 59% (N=20) at 5-year follow-up, respectively. Five years following treatment, only the BoP reduction was statistically significant compared to baseline (p<0.001), and no difference was found in PD (p=0.318) and in marginal peri-implant bone level (p=0.064). At 1-year follow-up, the surgical reconstructive therapy showed clinical improvement and radiographic defect filling. However, the results appeared to be unpredictable over time, due to a progressive decrease in the bone filling of the peri-implant defects and an increase in the mean PD.

Supramolecular self-assembled carbon nitride for the degradation of tetracycline hydrochloride

Graphitic carbon nitride microspheres photocatalyst (CN-MCA) was prepared through supramolecular self-assembly with post-heating treatment, which starts from the combination of the raw materials melamine and cyanuric acid. The as-prepared samples were characterized in detail by X-ray diffraction, Fourier transform infrared spectroscopy, new high-resolution field-emission scanning electron microscopy, specific surface areas analysis, UV–Vis diffused reflectance spectrum, photoluminescence spectrum, and thermal analysis. The structural characterization results reveal that the as-prepared CN-MCA has the same chemical structure as CN-M, but appears as microspheres with nanoporous surfaces. Compared to the CN-M, CN-MCA microspheres exhibit higher specific surface areas, stronger optical absorption and lower PL intensity, which allow more active sites, more effective visible-light harvesting and more efficient migration rate of photogenerated charge. Consequently, we observed that CN-MCA microspheres exhibit higher photocatalytic activity in the photodegradation of tetracycline hydrochloride under visible light irradiation. Moreover, the degradation efficiency of tetracycline hydrochloric acid under 2 h of visible light irradiation was 80.54% when the dosage of CN-MCA was 1.0 g/L; the initial concentration of the tetracycline hydrochloride solution was 10 mg/L; and the initial pH was 7.

Improvement of dermal delivery of tetracycline using vesicular nanostructures.

The objective of this investigation was to study the potential use of nanoliposomes and nanotransfersomes in dermal delivery of tetracycline hydrochloride (TC) for acne treatment. Vesicular nanostructures were prepared by thin film hydration method and evaluated for their size, zeta potential, morphology, and entrapment efficiency. Minimal inhibitory concentration values of TC-loaded vesicles were evaluated and compared with TC aqueous solution against Staphylococcus epidermis. In vitro drug release and ex vivo drug permeation through the excised rat skin were performed to assess drug delivery efficiency. Particle size, zeta potential, and entrapment efficiency of prepared nanoliposomes and nanotransfersomes were found to be 75 and 78 nm, 17 and 7 mV, and 45 and 55%, respectively. Antimicrobial analysis indicated that there was no difference between vesicular formulations and aqueous solution of TC. In vitro drug release study indicated that nanoliposomes could release TC 2.6 folds more than nanotransfersomes, and skin permeation study showed that the permeability of TC-loaded nanotransfersomes was 1.6 times higher than nanoliposomes which was also confirmed by fluorescence microscope imaging. These findings concluded that nanoliposomal and especially nanotransfersomal formulations could be proposed as the potential approach for better therapeutic performance of TC against acne.

Synthesis and drug delivery property of silica nanotubes prepared using gelatin nanofibers as novel sacrificed template

Silica nanotubes were prepared using the gelatin nanofibers as novel sacrificed template via a sol-gel route with a subsequent calcination process. FT-IR spectrum showed that the siloxane bonds (Si-O-Si) were involved in the silica nanotubes. SEM observations showed that the silica nanotubes had an average diameter of 742±82nm with a hollow cavity of 513±68nm. The formation of the tubular hollow structure was attributed to the removal of gelatin template. After soaked in the solution of tetracycline hydrochloride (TH, one of the representative antibiotics) as model drug, the silica nanotubes favored the adsorption of TH with the loading efficiency of 38%. A sustained release behavior of TH was observed as the TH-loaded silica nanotubes were soaked in the phosphate buffer saline. The released TH was biologically active to strongly inhibit the growth of bacterial E. coli.

Rapid analysis of tetracycline hydrochloride solution by attenuated total reflection terahertz time-domain spectroscopy.

Despite numerous methods for the detection of antibiotic residues, they are usually destructive and require tedious pre-treatment. Terahertz time-domain spectroscopy (THz-TDS) is an emerging technology that has advantages for analyzing chemical and biological compounds since THz waves are very sensitive to the molecular vibrational modes. Here we incorporated attenuated total reflection technique into the THz-TDS and demonstrated that this technology (ATR THz-TDS) allowed to determine the complex refractive indices of tetracycline hydrochloride (TCH) solutions with high accuracy and could be used to predict their concentrations. Our results from the simple linear regression models indicated that the complex refractive index exhibited a monotonic decrease with an increase in the TCH concentration. This study will provide new knowledge about the concentration determination of a liquid sample that couldn't be elucidated with the conventional THz-TDS technologies.

A comparative analysis of root surface biomodification with ethylene diamine tetra acetic acid and tetracycline hydrochloride: An in vitro scanning electron microscopic study

BackgroundThe outcome of periodontal regenerative therapy depends upon the of the biocompatibility root surfaces to the regenerating periodontal tissues. This in vitro scanning electron microscopic (SEM) study was designed to evaluate and compare the demineralizing efficacy of ethylene diamine tetra acetic acid (EDTA), with that of tetracycline hydrochloride applied on to the mechanically treated root surfaces of periodontally involved tooth. MethodsForty specimens were prepared from teeth extracted due to advanced periodontal disease and divided into two groups. The study group was treated with an EDTA solution (pH 7.4) and the control group was treated with a tetracycline hydrochloride solution (pH 1.8). The photomicrographs obtained were assessed for presence of smear layer, number of exposed dentinal tubules, area occupied by tubule orifices along with intertubular surface appearance. The results thus obtained were analyzed statistically. ResultsBoth EDTA and tetracycline were effective in removing the smear layer and the exposure of the number of dentinal tubules. The diameters of the tubules and thereby the surface area occupied by the tubule orifices in the EDTA treated group were significantly greater than the tetracycline HCL treated group (p<0.05). ConclusionThe EDTA produced better effects than tetracycline by providing more demineralized area and collagen exposure at a neutral pH.

Panax Notoginsenosides Attenuates Pleural Inflammation in Rabbit Model

to investigate the effect of intrapleural PNS on rabbit pleural inflammation reaction, and determine the levels of transforming growth factor β1 (TGF-β1) and Vascular Endothelial Growth Factor (VEGF). Forty New Zealand white rabbits were divided into four groups. The rabbit pleural inflammation reaction model was established by injection of tetracycline hydrochloride solution into pleural cavity. Then PNS, urokinase (UK) and PBS were injected into the pleural cavity as experiment groups. While tetracycline hydrochloride solution was replaced by phosphate buffer solution (PBS) as control group. The pleural effusion was collected at 24 h, 48 h, 72 h and 96 h in all groups, and then biochemical indicators, TGF-β1 and VEGF were detected. On day 14, all animals were killed and pleural tissues were collected to perform hematoxylin eosin (HE) and Masson trichrome staining. The results indicated that levels of TGF-β1 and VEGF were significantly lower in PNS group than that in UK group and PBS group (P<0.05); and the levels of VEGF were maximum at 48 h in three experimental groups. The thickness of pleural was thinner in PNS group, and the number of inflammatory cells and fibroblasts was also decreased in PNS group. In conclusion, PNS could reduce production of TGF-β1 and VEGF, reduce number of inflammatory cells and fibroblast, and inhibit collagen production, which had better effects compared with UK. Our findings provide a new treatment strategy for inflammation reaction.

Inhibition of bacterial growth around gutta percha cones by different antimicrobial solutions using antibiotic sensitivity test (An in vitro study)

Background: Decontamination of gutta percha cones was important factor for success of root canal treatment. The aim of the present in vitro study was to identify and to compare the antimicrobial effect of following disinfection solutions: 0.2% chlorhexidine gluconate, Iodine, tetracycline hydrochloride solution, EDTA & formocresol mixed with zinc oxide eugenol, on E faecalis, E coli and Candida albicans using sensitivity test Materials and Methods: Three types of microorganisms were isolated from infected root canals (E faecalis, E coli and Candida albicans) and cultured on Mueller Hinton agar petri-dishes. Disinfection of gutta percha cones done by immersion in six disinfection solutions (six groups), the groups are: distill water (used as control group), 0.2% chlorhexidine gluconate, Iodine, tetracycline hydrochloride solution, EDTA & formocresol mixed with Zinc oxide eugenol. The immersion times were 5 min. and the incubation was aerobically at 37 °C for 24 hr. for bacterial species and at 28°C for 48 hr. for candida albicans. After incubation, zones of inhibition (no growth of bacteria) were examined around the gutta percha cones & diameters of the zones were measured with a boley gauge. The means of inhibition zones for each group were measures and statistically analyzed among groups using ANOVA and LSD tests at 0.05 significance level. Results: There is highly significant differences (P=0.000) among all the tested groups. 0.2% Chlorhexidine gluconate showed the maximum antibacterial efficacy (broader zones of inhibition) against E faecalis. Compound of formocresol + Zinc oxide eugenol showed the maximum antibacterial efficacy against Candida albicans, and E coli. The minimum antibacterial efficacy against Candida albicans occurred with tetracycline group, while against E faecalis and E coli occurred with EDTA group Conclusion: All the tested materials had antibacterial efficacy against Candida albicans, E faecalis and E coli; but chlorhexidine gluconate and compound of formocresol & Zinc oxide eugenol, are more effective agents for a rapid disinfection of gutta-percha cones in five minutes.

Comparison of the efficacy of ethylenediaminetetraacetic acid and tetracycline hydrochloride as root conditioning agents: An in vitro study

Objective: Root surfaces of periodontitis-affected teeth are hypermineralized and contaminated with cytotoxic and other biologically active substances. Various root conditioning agents have been recommended as an adjunct to mechanical root surface debridement to expose dentin collagen and cementum bound proteins. The aim of the present in vitro study was to compare the efficacy of ethylenediaminetetraacetic acid (EDTA) and tetracycline hydrochloride (HCl) as root conditioning agents on planed root surfaces. Materials and Methods: A total of 20 human maxillary anterior teeth indicated for extraction due to chronic periodontitis were collected and root planed. The teeth were sectioned and specimens were divided into two groups - Group I and II. Group I dentin specimens were treated with EDTA and Group II specimens were treated with tetracycline HCl solution at a concentration of 10% by active burnishing technique for 3 min. The root surface samples were then examined by scanning electron microscope. Results: The results of this study showed that EDTA and tetracycline HCl were equally effective in removing the smear layer. It was observed that the total and patent dentinal tubules were more in number in teeth treated with tetracycline when compared to EDTA group. However, EDTA was found to be much more effective as root conditioning agent because it enlarged the diameter of dentinal tubules more than that of tetracycline HCl. Conclusion: The results of in vitro study showed that both the agents are good root conditioning agents if applied in addition to periodontal therapy. However, further studies are required to establish the in vivo importance of EDTA and tetracycline HCL as root conditioners.

Detection of chemical marks for stocking purposes in sturgeon species

Summary The objective of this study was to test if pectoral fin rays, a widely used structure in ageing studies for live sturgeons, are reliable to assess mass-marking success in endangered sturgeon species, particularly European sturgeon Acipenser sturio. Marking success and thus the proper identification of fish stocked at a young age are critical to evaluate the effectiveness of conservation strategies. In this study, a total of 60 1-month old Siberian sturgeons Acipenser baerii was marked. Thirty specimens were marked by immersion in tetracycline hydrochloride solution at a concentration of either 300 ppm or 600 ppm. 30 additional specimens were immersed in alizarin red S solution at a concentration of either 100 ppm or 200 ppm. Four weeks after marking, the sturgeons were sacrificed and marking success was compared between pectoral fin rays and two other structures: otoliths and dorsal scutes. Marking success in pectoral fin rays was variable depending on the marking protocol, being as low as 7% for one of the marking treatments. In comparison, marking success in dorsal scutes exceeded 90% regardless of the treatment. Similar high success was also seen for otoliths marked with alizarin red S. Moreover, for all treatments, more than 20% of the marked pectoral fin rays marked showed discontinuous marks, which cannot be considered of acceptable quality for reliable mark detection. In comparison, only completely continuous marks were observed in dorsal scutes and otoliths. Auto-fluorescence and ontogenic formation in pectoral fin rays are hypothesized to cause mark detection deficiencies in this hard structure. Thus, pectoral fin rays should not be used to identify hatchery-reared sturgeons exposed to fluorescent markers at a young stage.

Effect of various techniques of tetracycline hydrochloride demineralization on root dentin surface: A scanning electron microscopic study

Aim : To evaluate the in-vitro effect of various techniques of Tetracycline Hydrochloride application on root dentin surface at different magnifications of scanning electron microscopic (SEM). Materials and Methods : Twenty human teeth were collected and stored in distilled water after soft tissue removal using hand instruments. The apical third of each root was removed remaining mid-third region was sectioned longitudinally through the root canal following removal of its cementum with a tapered fissure bur. The dentin blocks were divided into 4 groups having 5 samples in each group. A tetracycline hydrochloride solution was prepared by adding the contents of one 500 mg capsule to 5 ml of distilled water. The application time of the tetracycline hydrochloride was 5 minutes. After the treatment of the root surfaces, the samples were fixed in 2.5% glutaraldehyde prepared in phosphate buffer (pH 7.3) for 24 hours at 4°C and prepared for SEM. Mean and standard deviation were estimated from the samples for each study group. Mean values were compared by either ONE-WAY ANOVA with Tukey - HSD procedure. Results : All technique of tetracycline application shows removal of smear layer and exposure of dentinal tubule orifices. Burnishing technique showed significant difference than immersion technique and saturation technique. Conclusion : In view of these present findings, tetracycline hydrochloride as a root conditioner may be evaluated in vivo studies. It is reasonable to expect lesser tissue destruction and better regeneration of periodontal tissues if it is used as a root conditioner during periodontal regeneration procedures.

Fibrin glue application in conjunction with tetracycline hydrochloride root conditioning and semilunar coronally repositioned flap in the treatment of gingival recession

The purpose of this case report is to present the results of Fibrin Adhesive System (FAS) application, a topical biological tissue adhesive in the treatment of maxillary buccal recessions. A 40-year-old male patient presented with a pair of class I buccal recession defects on maxillary cuspids. Clinical parameters were recorded at baseline, 1 month, and 3 months. Semilunar coronally repositioned flap (Tarnow's technique), root debridement, root conditioning with tetracycline hydrochloride solution and one of the defect was treated with FAS application. Significant recession, height reduction, and attachment gain were observed with the FAS application defect site. About 50% of root coverage was noted in the FAS-treated defect and almost no root coverage in the defect site with no FAS application. Semilunar coronally repositioned flap with FAS application is an effective procedure for root coverage in anterior teeth. The addition of FAS improves the amount of root coverage, especially in relatively shallow defects.

Symptomatic hepatic cyst in a child: treatment with single-shot injection of tetracycline hydrochloride

The prevalence of hepatic cysts is 0.1% to 0.5% based on autopsy studies, and 2.5% based on US examinations. Percutaneous therapies are a new alternative to surgery. They include simple percutaneous aspiration, catheter drainage alone, and catheter drainage with sclerotherapy. We present an 11-year-old boy admitted to hospital because of abdominal pain. A diagnosis of simple hepatic cyst was made, which was treated with aspiration and tetracycline hydrochloride solution (5%) injection into the cystic cavity. Complete regression was seen on US and MRI examination at 3 months, with total collapse and deflation of the cyst. The cyst regressed totally, leaving a hyperechoic linear scar on US examination at 1 year. On the basis of the clinical and imaging results obtained, percutaneous sclerotherapy of hepatic cysts can be recommended as the treatment of choice and as a valid alternative to laparoscopy in children.

Healing of Dehiscence Defects Following Root Surface Demineralization With Tetracycline: A Histologic Study in Monkeys

The purpose of this study was to histologically evaluate the healing of experimental dehiscence defects after surface demineralization with tetracycline hydrochloride. Six adult male monkeys (Cebus apella) were used in this study. Dehiscence defects were surgically created on the buccal aspect of the mandibular lateral incisors in all animals. The root surfaces were debrided and planed. In a split-mouth design, a 10% tetracycline hydrochloride solution was applied to one tooth for 4 minutes (T group), followed by irrigation with saline. The contralateral tooth served as a control (C group). The flaps were repositioned and sutured. The animals were sacrificed at 6 months postoperatively and histological sections were processed. Computer-assisted histomorphometric analysis was used to evaluate the formation of new cementum, new bone, new connective tissue attachment, and length of the epithelium (junctional and sulcular). Bone regeneration was similar in both groups (1.5 +/- 0.3 mm for the T group and 1.5 +/- 0.6 mm for the C group). The C group showed more new cementum than the T group (2.3 +/- 0.3 mm versus 2.2 +/- 0.3 mm) as well as a longer epithelium (1.0 +/- 0.3 mm versus 0.9 +/- 0.2 mm). The T group presented more new connective tissue attachment (3.1 +/- 0.2 mm) than the C group (2.9 +/- 0.6 mm). However, no statistically significant differences were detected between the two groups. The amount of new attachment was similar in both groups. Root conditioning with 10% tetracycline solution did not produce any additional new attachment in comparison to the controls.