Evaluation of shear bond strength of two resin-based composites and glass ionomer cement to pure tricalcium silicate-based cement (Biodentine?)

Objectives

Tricalcium silicate is the major constituent phase in mineral trioxide aggregate (MTA). It is thus postulated that pure tricalcium silicate can replace the Portland cement component of MTA. The aim of this study was to evaluate bond strength of methacrylate-based (MB) composites, silorane-based (SB) composites, and glass ionomer cement (GIC) to Biodentine^® and mineral trioxide aggregate (MTA).

Material and Methods

Acrylic blocks (n=90, 2 mm high, 5 mm diameter central hole) were prepared. In 45 of the samples, the holes were fully filled with Biodentine^® and in the other 45 samples, the holes were fully filled with MTA. The Biodentine^® and the MTA samples were randomly divided into 3 subgroups of 15 specimens each: Group-1: MB composite; Group-2: SB composite; and Group-3: GIC. For the shear bond strength (SBS) test, each block was secured in a universal testing machine.

Results

The highest (17.7±6.2 MPa) and the lowest (5.8±3.2 MPa) bond strength values were recorded for the MB composite-Biodentine^® and the GIC-MTA, respectively. Although the MB composite showed significantly higher bond strength to Biodentine (17.7±6.2) than it did to MTA (8.9±5.7) (p<0.001), the SB composite (SB and MTA=7.4±3.3; SB and Biodentine^®=8.0±3,6) and GIC (GIC and MTA=5.8±3.2; GIC and Biodentine=6.7±2.6) showed similar bond strength performance with MTA compared with Biodentine (p=0.73 and p=0.38, respectively).

Conclusions

The new pure tricalcium-based pulp capping, repair, and endodontic material showed higher shear bond scores compared to MTA when used with the MB composite.     

Effect of MTA-based sealer on the healing of periapical lesions

Some manufacturers have recently added specific components to improve the ease of handling and insertion material properties of MTA in order to create MTA-based sealers.

Objective:

The aim of this study was to evaluate the healing of periapical lesions in canine teeth after a single session of endodontic treatment with MTA Fillapex^® compared with Sealapex or Endo-CPM-Sealer^®.

Material and Methods:

Sixty-two root canals were performed on two 1-year-old male dogs. After coronal access and pulp extirpation, the canals were exposed to the oral cavity for 6 months in order to induce periapical lesions. The root canals were prepared, irrigated with a solution of 2.5% sodium hypochlorite and filled with gutta-percha and different sealers, according to the following groups: 1) Sealapex; 2) Endo-CPM-Sealer^®; and 3) MTA Fillapex. Some teeth with periapical lesions were left untreated for use as positive controls. Healthy teeth were used as negative controls. After 6 months, the animals were sacrificed and serial sections from the roots were prepared for histomorphologic analysis and stained with hematoxylin and eosin and the Brown and Brenn technique. The lesions were scored according to pre-established histomorphologic parameters and the scores statistically analyzed using the Kruskal-Wallis test.

Results:

All 3 materials produced similar patterns of healing (p>0.05); in particular, persistent inflammation and absence of complete periapical tissue healing were consistently noted.

Conclusions:

Preparation of the infected root canals followed by filling with the materials studied was insufficient to provide complete healing of the periapical tissues.     

Human tooth germ stem cell response to calcium-silicate based endodontic cements

Objective

The aim of this study was to compare the cytotoxic effects of endodontic cements on human tooth germ stem cells (hTGSCs). MTA Fillapex, a mineral trioxide aggregate (MTA)-based, salicylate resin containing root canal sealer, was compared with iRoot SP, a bioceramic sealer, and AH Plus Jet, an epoxy resin-based root canal sealer.

Material and Methods

To evaluate cytotoxicity, all materials were packed into Teflon rings (4 mmµ3 mm) and co-cultured with hTGSCs with the aid of 24-well Transwell permeable supports, which had a pore size of 0.4 µm. Coverslips were coated with MTA Fillapex, iRoot SP and AH Plus Jet and each coverslip was placed onto the bottom of one well of a six-well plate for scanning electron microscopy (SEM) analysis. Before the cytotoxicity and SEM analysis, all samples were stored at 37ºC and at 95% humidity and 5% CO₂ for 24 hours to set. The cellular viability was analyzed using MTS test (3-(4,5-dimethyl-thiazol-2-yl)-5-(3-carboxy-methoxy-phenyl)-2-(4-sulfo-phenyl)-2H-tetrazolium). The cytotoxic effects and SEM visualization of the tested materials were analyzed at 24-hour, 72-hour, one-week and two-week periods.

Results

On the 1^st day, only MTA Fillapex caused cytotoxicity compared to negative control (NC) group (p<0.008). No significant difference was observed between the other tested materials at this period (p>0.05). After 14 days of incubation with the test materials, MTA Fillapex exhibited significantly higher cytotoxicity compared with iRoot SP, AH Plus Jet and the NC group (P<0.008). In the SEM analysis, the highest levels of cell attachment were observed for iRoot SP and the control group. After 24 hours, MTA Fillapex reduced the number of cells attached to the surface.

Conclusions

Within the limitations of this study, sealers exerted different cytotoxic effects on hTGSCs. Although all materials have exerted cellular toxicity, iRoot SP and AH Plus Jet may promote better attachment to hTGSCs.     

The comparison of MTA,Geristore® and Amalgam with or without Bioglass as a matrix in sealing the furcal perforations (in vitro study)

Aim

The objective of this in vitro was to assess the sealing ability of MTA, Geristore®, and amalgam with and without Bioglass as a matrix used to repair furcation perforations in mandibular molars by using dye penetration.

Materials and methods

One hundred mandibular molars were randomly divided into six experimental groups. Five teeth with perforation were used as positive control while five teeth without perforation were used as negative control group. Furcal perforations were made in the teeth. Perforations were repaired with amalgam in group 1, amalgam and Bioglass in group 2, MTA in group 3, MTA and Bioglass in group 4, Geristore® in group 5, and Geristore® and Bioglass in group 6. All repairing materials were allowed to set for 72 h. Leakage at the repaired sites was then evaluated using dye penetration and clearing technique under stereomicroscope.

Results

The perforations repaired with MTA and Geristore® leaked significantly less than amalgam (p = 0.000). Bioglass reduced sealing ability of MTA and Geristore® significantly (p = 0.000, p = 0.019), while reduced the sealing ability of amalgam insignificantly (p = 0.78).

Conclusion

MTA and Geristore® have shown acceptable sealing ability in furcal perforation in comparison to amalgam while Bioglass as a matrix beneath them has reduced their sealing ability.     

Microbial contamination and disinfection methods of pacifiers

Objectives

To evaluate the microbial contamination of pacifiers by Mutans Streptococci (MS) and the efficacy of different methods for their disinfection.

Methods

Twenty-eight children were assigned to a 4-stage changeover system with a 1-week interval. In each stage, children received a new pacifier and the parents were instructed to maintain their normal habits for 1 week. After this time, the pacifiers were subjected to the following 4 disinfection methods: spraying with 0.12% chlorhexidine solution, Brushtox^® or sterile tap water, and immersion in boiling tap water for 15 minutes. Microbiological culture for MS and Scanning Electron Microscopy (SEM) were performed. The results were analyzed statistically by Friedman’s non-parametric test (a=0.05).

Results

The 0.12% chlorhexidine spray was statistically similar to the boiling water (p>0.05) and more effective than the Brushtox^® spray and control (p<0.05). The analysis of SEM showed the formation of a cariogenic biofilm in all groups with positive culture.

Conclusions

Pacifiers become contaminated by MS after their use by children and should be disinfected routinely. Spraying with a 0.12% chlorhexidine solution and immersion in boiling water promoted better disinfection of the pacifiers compared with a commercial antiseptic toothbrush cleanser (Brushtox^®).     

Radiopacity evaluation of Portland and MTA-based cements by digital radiographic system

Objective

The aim of the present study was to evaluate the radiopacity of Portland and MTA-based cements using the Digora TM digital radiographic system.

Material and Methods

The performed tests followed specification number 57 from the American National Standard Institute/American Dental Association (2000) for endodontic sealing materials. The materials were placed in 5 acrylic plates, especially designed for this experiment, along with a graduated aluminum stepwedge varying from 1 to 10 mm in thickness. The set was radiographed at a 30 cm focus-object distance and with 0.2 s exposure time. After the radiographs were taken, the optical laser readings of radiographs were performed by Digora TM system. Five radiographic density readings were performed for each studied material and for each step of the aluminum scale.

Results

White ProRoot MTA (155.99±8.04), gray ProRoot MTA (155.96±16.30) and MTA BIO (143.13±16.94) presented higher radiopacity values (p<0.05), while white non-structural Portland (119.76±22.34), gray Portland (109.71±4.90) and white structural Portland (99.59±12.88) presented lower radiopacity values (p<0.05).

Conclusions

It was concluded that MTA-based cements were the only materials presenting radiopacity within the ANSI/ADA specifications.     

MAXIMUM INHIBITORY DILUTION OF MOUTHWASHES CONTAINING CHLORHEXIDINE AND POLYHEXAMETHYLENE BIGUANIDE AGAINST SALIVARY STAPHYLOCOCCUS AUREUS

Objective:

The aim of the present study was to determine the in vitro maximum inhibitory dilution (MID) of two chlorhexidine-based oral mouthwashes (CHX): Noplak®, Periogard®, and one polyhexamethylene biguanide-based mouthwash (PHMB): Sanifill Premium® against 28 field Staphylococcus aureus strains using the agar dilution method.

Materials and Methods:

For each product, decimal dilutions ranging from 1/10 to 1/655,360 were prepared in distilled water and added to Mueller Hinton Agar culture medium. After homogenization, the culture medium was poured onto Petri dishes. Strains were inoculated using a Steers multipoint inoculator and dishes were incubated at 37°C for 24hours. For reading, MID was considered as the maximum dilution of the mouthwash still capable of inhibiting microbial growth.

Results:

Sanifill Premium® inhibited the growth of all strains at 1/40 dilution and of 1 strain at 1/80 dilution. Noplak® inhibited the growth of 23 strains at 1/640 dilution and of all 28 strains at 1/320 dilution. Periogard® showed inhibited growth of 7 strains at 1/640 dilution and of all 28 strains at 1/320 dilution. Data were submitted to Kruskal-Wallis statistical test, showing significant differences between the mouthwashes evaluated (p<0.05). No significant difference was found between Noplak® and Periogard® (p>0.05). Sanifill Premium® was the least effective (p<0.05).

Conclusion:

It was concluded that CHX-based mouthwashes present better antimicrobial activity against S. Aureus than the PHMB-based mouthwash.     

Influence of root canal sealer on the radiographic appearance of filling voids in maxillary single-rooted teeth

Objective

This study compared the influence of three epoxy resin-based sealers with distinct radiopacities on the observers'' ability to detect root canal filling voids during radiographic analysis.

Material and methods

The root canals of 48 extracted maxillary canines were prepared and divided into three groups. Each group was laterally condensed with one sealer (AH Plus^TM, Acroseal^® or a non-radiopaque sealer), and a longitudinal void was simulated in half of the specimens from each group (n=8). Buccolingual radiographs were obtained and randomly interpreted for voids by a radiologist and an endodontist in a blinded fashion. Teeth were cut and inspected under a microscope to confirm the position of void. Differences in sensitivity and specificity between groups and examiners were compared using the Fisher''s Exact and McNemar tests, respectively (α=0.05).

Results

Significantly lower sensitivity levels (p<0.05) were observed in the coronal portion of fillings performed with both radiopaque sealers. Specificity values for Acroseal^® were significantly higher (p<0.05) in the coronal and apical portions of fillings.

Conclusions

The type of root canal sealer can affect the observers'' ability to detect root canal filling voids during radiographic analysis of upper single-rooted teeth.     

QMix? irrigant reduces lipopolysacharide (LPS) levels in an in vitro model

The presence of endotoxin inside the root canal has been associated with periapical inflammation, bone resorption and symptomatic conditions.

Objectives

To determine, in vitro, the effect of QMix^® and other three root canal irrigants in reducing the endotoxin content in root canals.

Material and Methods

Root canals of single-rooted teeth were prepared. Samples were detoxified with Co-60 irradiation and inoculated with E. coli LPS (24 h, at 37°C). After that period, samples were divided into 4 groups, according to the irrigation solution tested: QMix^®, 17% EDTA, 2% chlorhexidine solution (CHX), and 3% sodium hypochlorite (NaOCl). LPS quantification was determined by Limulus Amebocyte Lysate (LAL) assay. The initial counting of endotoxins for all samples, and the determination of LPS levels in non-contaminated teeth and in contaminated teeth exposed only to non-pyrogenic water, were used as controls.

Results

QMix^® reduced LPS levels, with a median value of 1.11 endotoxins units (EU)/mL (p<0.001). NaOCl (25.50 EU/mL), chlorhexidine (44.10 EU/mL) and positive control group (26.80 EU/mL) samples had similar results. Higher levels were found with EDTA (176.00 EU/mL) when compared to positive control (p<0.001). There was no significant difference among EDTA, NaOCl and CHX groups. Negative control group (0.005 EU/mL) had statistically significant lower levels of endotoxins when compared to all test groups (p<0.001).

Conclusion

QMix^® decreased LPS levels when compared to the other groups (p<0.001). 3% NaOCl, 2% CHX and 17% EDTA were not able to significantly reduce the root canal endotoxins load.     

Comparison of static friction with self-ligating,modified slot design and conventional brackets

Objective

To compare the static frictional forces generated at the bracket/wire interface of stainless steel brackets with different geometries and angulations, combined with orthodontic wires of different diameters.

Material and Methods

The frictional forces were evaluated with three different types of metal brackets: a passive self-ligating (SmartClip^TM, 3M/Unitek, Monrovia, USA), with a modified slot design (Mini Uni Twin^TM, 3M/Unitek, Monrovia, USA) and conventional (Kirium, Abzil, São José do Rio Preto, Brazil). The samples were mounted in a testing device with three different angulations and tested with 0.014" and 0.018" stainless steel wires (American Orthodontics, Sheboygan, USA). The static frictional force was measured using a universal testing machine (DL 500, EMIC^®, São José dos Pinhais, Brazil) with a crosshead speed of 1 mm/min. Statistical analysis was performed by two-way ANOVA followed by Bonferroni''s post hoc test.

Results

There was a significant difference (p<0.05) in static friction when the three types of brackets were tested with the same wire size. The wire diameter influenced friction only when the brackets had a 10º angulation (p<0.05). The angulation influenced friction (p<0.05) when the brackets were associated with a 0.018" wire.

Conclusion

Brackets with a modified slot design showed intermediate static frictional force values between the conventional and self-ligating brackets tested.     

Efficacy of HPA Lanolin? in treatment of lip alterations related to chemotherapy

The side effects of chemotherapy on the lips may cause esthetic and functional impact and increase the risk of infection. HPA Lanolin^® is an option for supportive therapy because it has anti-inflammatory, antimicrobial and moisturizing properties.

Objective:

To evaluate the efficacy of this product in the prevention of lip alterations in a population of patients undergoing chemotherapy.

Material and Methods:

Patients undergoing chemotherapy (n=57) were examined and distributed into two groups: study (used HPA Lanolin^®) and control (without supportive therapy on the lips). We evaluated the patients two weeks after chemotherapy, registering oral alterations, symptoms of pain, discomfort, limitation of mouth opening and dehydration, classified according to a visual analogue scale.

Results:

Patients who used HPA Lanolin^® had lower dehydration and experienced improvement of lip dryness (p<0.001). The main symptoms were dehydration, discomfort, limitation of mouth opening, pain. The main clinical signs were dry lips, mucositis, cheilitis, hematoma, swelling and cracking. We found no difference concerning the variables of pain, discomfort, and limitation of mouth opening between the study and control group.

Conclusions:

We suggest that HPA Lanolin^® is effective in reducing the symptoms of dehydration and the signs of lip dryness resulting from toxicity of chemotherapy, proving to be an interesting alternative supportive therapy for cancer patients.     

The susceptibility of Streptococcus mutans to antibacterial photodynamic therapy: a comparison of two different photosensitizers and light sources

Streptococcus mutans is the main etiological agent for dental caries. Recently, photodynamic therapy (PDT) has been introduced as a new modality in bacterial decontamination.

Objective

This in vitro study was carried out to evaluate the susceptibility of Streptococcus mutans to antibacterial PDT using two different photosensitizers and light sources.

Material and Methods

Standard suspensions of S. mutans were exposed to laser light at 662 nm and Radachlorin^® or LED 630 nm in combination with Toluidine blue O (TBO). Radiation-only groups, photosensitizer alone, and groups with no treatment were used as controls. Bacterial suspension from each treatment was subcultured onto the surface of Mueller-Hinton agar plates and bacterial growth was assessed. The results were analyzed by analysis of variance and Tukey test (p<0.05).

Results

PDT with TBO and Radachlorin^® significantly reduced S. mutans viability, whereas no difference was observed between two groups of PDT. In the groups treated just with the photosensitizer or irradiated alone, no significant reduction of S. mutans colonies was observed.

Conclusion

S. mutans colonies were susceptible to either 662 nm laser or LED light in the presence of Radachlorin^® and TBO respectively with no priority.     

A Comparative Study of Shaping Ability of four Rotary Systems

Purpose

This study compared the cutting area, instrumentation time, root canal anatomy preservation and non-instrumented areas obtained by F360^®, Mtwo^®, RaCe^® and Hyflex^® files with ISO size 35.

Material and Methods

120 teeth with a single straight root and root canal were divided into 4 groups. Working length was calculated by using X-rays. The teeth were sectioned with a handpiece and a diamond disc, and the sections were observed with Nikon SMZ-2T stereoscopic microscope and an Intralux 4000-1 light source. The groups were adjusted with a preoperative analysis with AutoCAD. The teeth were reconstructed by a #10 K-File and epoxy glue. Each group was instrumented with one of the four file systems. The instrumentation time was calculated with a 1/100 second chronometer. The area of the thirds and root canal anatomy preservation were analyzed with AutoCAD 2013 and the non-instrumented areas with AutoCAD 2013 and SMZ-2T stereoscopic microscope. The statistical analysis was made with Levene’s Test, ANOVA, Bonferroni Test and Pearson´s Chi-square.

Results

Equal variances were shown by Levene’s Test (P > 0.05). ANOVA (P > 0.05) showed the absence of significant differences. There were significant differences in the instrumentation time (P < 0.05). For root canal anatomy preservation and non-instrumented areas, there were no significant differences between all systems (P > 0.05).

Conclusions

The 4 different rotary systems produced similar cutting area, root canal anatomy preservation and non-instrumented areas. Regarding instrumentation time, F360^® was the fastest system statistically.Key words: Cutting ability, cross-sections, instrumentation time, rotary instruments     

Long-term cytotoxic effects of contemporary root canal sealers

Objectives:

The aim of the present study was to investigate the effects of root canal sealers on the cytotoxicity of 3T3 fibroblasts during a period of 5 weeks.

Material and Methods:

Fibroblasts (3T3, 1x10⁵ cells per well) were incubated with elutes of fresh specimens from eight root canal sealers (AH Plus, Epiphany, Endomethasone N, EndoReZ, MTA Fillapex, Pulp Canal Sealer EWT, RoekoSeal and Sealapex) and with elutes of the same specimens for 5 succeeding weeks after immersing in simulated body fluid. The cytotoxicity of all root canal sealers was determined using the MTT assay. Data were analyzed using ANOVA and Tukey''s test.

Results:

RoekoSeal was the only sealer that did not show any cytotoxic effects (p<0.05). All the other tested sealers exhibited severe toxicity initially (week 0). MTA Fillapex remained moderately cytotoxic after the end of experimental period. Toxicity of the other tested sealers decreased gradually over time. The evaluated root canal sealers presented varying degrees of cytotoxicity, mainly in fresh mode.

Conclusions:

RoekoSeal had no cytotoxic effect both freshly mixed and in the other tested time points. MTA Fillapex was associated with significantly less cell viability when compared to the other tested root canal sealers.     

Effect of abutment angulation in the retention and durability of three overdenture attachment systems: An in vitro study

PURPOSE

This in vitro study investigated and compared the durability and retention of three types of attachments.

MATERIALS AND METHODS

Three commercially available attachments were investigated: Clix®, Dalbo-Plus® and Locator®. In total, 72 samples of these attachments were placed in the acrylic resin forms and subjected to mechanical testing (5400 cycles of insertion and removal) over the respective ball or Locator abutments immersed in artificial saliva at pH 7 and 37℃. The abutments were placed at angulations of 0°, 10° and 20°. The retention force was recorded at the beginning and after 540, 1080, 2160, 3240, 4320 and 5400 insertion-removal cycles.

RESULTS

The results revealed that there were significant differences in the average values of the insertion/removal force due to angulation (F _(2.48) = 343619, P<.05) and the type of attachment (F _(7.48) = 23.220, P<.05).

CONCLUSION

Greater angulation of the abutments was found to influence the retention capacity of the attachments, and the fatigue test simulating 5 years of denture insertion and removal did not produce wear in the metal abutments.     

The sealing ability of MTA apical plugs exposed to a phosphate-buffered saline

Objective

The aim of this study was to evaluate the influence of exposure of the mineral trioxide aggregate (MTA) - with and without calcium chloride (CaCl₂) - to phosphate-buffered saline (PBS) on the apical microleakage using a glucose leakage system.

Material and Methods

Sixty root segments were randomly divided into 4 experimental groups (n=15). After resecting the apical segments and enlarging the canals with Gates-Glidden drills, the apical cavities were filled with MTA with or without CaCl₂ and the root canals were dressed with a moistened cotton pellet or PBS, as follows: 1) MTA/cotton pellet; 2) MTA/PBS; 3) MTA+10%CaCl₂/cotton pellet; 4) MTA+10%CaCl₂/PBS. All root segments were introduced in floral foams moistened with PBS. After 2 months, all root segments were prepared to evaluate the glucose leakage along the apical plugs. The amount of glucose leakage was measured following an enzymatic reaction and quantified by a spectrophotometer. Four roots were used as controls. The data were analyzed using Kruskal-Wallis and Mann-Whitney tests (p<0.05).

Results

There were no differences between groups 1 and 2 (p>0.05), and 3 and 4 (p>0.05). The addition of CaCl₂ to the MTA significantly decreased its sealing ability (p<0.05).

Conclusion

The interaction with PBS did not improve the MTA sealing ability. The addition of CaCl₂ to the MTA negatively influenced the apical seal.     

Physicochemical properties of endodontic sealers of different bases

Objective

To assess the setting time (ST), flow (FL), radiopacity (RD), solubility (SB) and dimensional change following setting (DC) of different sealers (AH Plus^®, Polifil, Apexit Plus^®, Sealapex^®, Endométhasone^® and Endofill^® according to American National Standards Institute/American Dental Association (ANSI/ADA) Specification 57.

Material and methods

Five samples of each material were used for each test. For ST, cast rings were filled with sealers and tested with a Gilmore needle. For FL, the sealer was placed on a glass plate. After 180 s, another plate with 20 g and a load of 100 g were applied on the material, and the diameters of the discs formed were measured. In RD, circular molds were filled with the sealers, radiographed and analyzed using Digora software. For SB, circular molds were filled with the sealers, a nylon thread was placed inside the material and another glass plate was positioned on the set, pressed and stored at 37ºC. Samples were weighed, placed in water, dried and reweighed. The water used for SB was analyzed by atomic absorption spectrometry. For DC, circular molds were filled with the sealers, covered by glass plates and stored at 37ºC. Samples were measured and stored in water for 30 days. After this period, they were dryed and measured again.

Results

Regarding ST, AH Plus^®, Apexit^® and Endofil^® sealers are in accordance with ANSI/ADA standards. Endométhasone''s manufacturer did not mention the ST; Polifil is an experimental sealer and Sealapex^® did not set. Considering RD, SB and DC, all sealers were in accordance with ANSI/ADA. The spectrometric analysis showed that a significant amount of K⁺ and Zn2⁺ ions was released from Apexit Plus^® and Endofill^®, respectively.

Conclusion

Except for DC, all other physicochemical properties of the tested sealers conformed to ANSI/ADA requirements.     

A Prospective,Randomized, Double-Blind,Placebo-Controlled Clinical Trial Comparing the Efficacy of Anti-edema Drugs for Edema Control in Orthognathic Surgery Using Digitizer 3-D to Measure Facial Swelling

Introduction

Orthognathic surgery involves making several osteotomies. Any osteotomies leads to varying degrees of post-operative swelling. The aim of this study was to evaluate the effectiveness of anti-edema drugs for the control of edema, using Digitizer 3D™ for measuring soft-tissue thickness, in patients who underwent bimaxillaryorthognathic surgery.

Materials and Methods

In this double-blinded, randomized, control trial, 24 patients (study group: 12 patients, control group: 12 patients) in whom bimaxillary orthognathic surgery was indicated, were included in this study. All swelling measurements were expressed as total 3-D area of the landmarks (cm²) in T0 pre-operative, T1 first day after surgery, T2 fourth day after surgery, T3 4 months after surgery. For each patient we compared, by adding left and right area, the increase of swelling between T1–T0, T2–T0 and T1–T3.

Results

The differences T0–T1 are highly significant (p < 0.01) between group 1 or study group (treated with Venoplant^®) and group 2 (control group); the differences T0–T2 are significant (p < 0.05) between group 1 (treated with Venoplant^®) and group 2 (control group). The differences T1–T3 are significant (p < 0.05) between group 1 (treated with Venoplant^®) and group 2 (control group).

Discussion

The present study suggests that Venoplant^® significantly decreases postoperative edema in orthognathic surgery, thus precluding long-term corticosteroid use.     

Spectrophotometric analysis of crown discoloration induced by MTA- and ZnOE-based sealers

Crown discoloration can be induced by root canal sealer remnants following root canal treatment.

Objective:

The aim of this study was to evaluate chromatic alterations in human tooth crowns induced by a Mineral Trioxide Aggregate-based sealer (MTA Fillapex^® and a commonly used ZnOE-based sealer (Roth-811). The tested null hypothesis was that the application of the materials did not induce clinically perceptible crown discoloration (Ho: CIE color difference ΔE<3.7).

Material and Methods:

Forty five fully developed, intact, mandibular third molars were sectioned 1 mm below the cemento-enamel junction. The pulp chambers were chemomechanically debrided via the cervical access. The specimens were randomly assigned into three groups Group 1: MTA Fillapex, Group 2: Roth 811, Group 3: Negative control (unfilled) and immersed in individually marked vials containing distilled water up to the cervix (37±1º C). The spectral reflectance lines were recorded by utilizing a UV-VIS spectrophotometer equipped with integration sphere in the visual spectrum at baseline, 1 week, 1 and 3 months after material placement. Data were transformed into values of the CIE L*a*b* color system and the corresponding ΔE values were calculated. Statistical analysis was performed using two-way mixed ANOVA models, at p=0.05 level of significance.

Results:

A statistically significant increase in a* and b* chromatic parameters of the MTA Fillapex Group was measured. However, ΔE values did not exceed the human eye perceptibility threshold (set at ΔE<3.7) during the experimental period (ΔEt3=2.88). In Roth-811 Group, a statistically significant decrease in L* and a statistically significant increase in a* and b* chromatic parameters was measured, during all observation periods. Resultant ΔE values exceeded the human eye perceptibility threshold after 1 week (ΔEt1=5.65).

Conclusions:

Application of MTA Fillapex in tooth crowns resulted in minimal color alterations, while Roth 811 induced severe discoloration, in vitro. It could be suggested that, in terms of aesthetics, the use of MTA Fillapex appears to be favorable.     

Caries risk assessment in schoolchildren - a form based on Cariogram? software

Identifying caries risk factors is an important measure which contributes to best understanding of the cariogenic profile of the patient. The Cariogram^® software provides this analysis, and protocols simplifying the method were suggested.

Objectives

The aim of this study was to determine whether a newly developed Caries Risk Assessment (CRA) form based on the Cariogram^® software could classify schoolchildren according to their caries risk and to evaluate relationships between caries risk and the variables in the form.

Material and Methods

150 schoolchildren aged 5 to 7 years old were included in this survey. Caries prevalence was obtained according to International Caries Detection and Assessment System (ICDAS) II. Information for filling in the form based on Cariogram^® was collected clinically and from questionnaires sent to parents. Linear regression and a forward stepwise multiple regression model were applied to correlate the variables included in the form with the caries risk.

Results

Caries prevalence, in primary dentition, including enamel and dentine carious lesions was 98.6%, and 77.3% when only dentine lesions were considered. Eighty-six percent of the children were classified as at moderate caries risk. The forward stepwise multiple regression model result was significant (R2=0.904; p<0.00001), showing that the most significant factors influencing caries risk were caries experience, oral hygiene, frequency of food consumption, sugar consumption and fluoride sources.

Conclusion

The use of the form based on the Cariogram^® software enabled classification of the schoolchildren at low, moderate and high caries risk. Caries experience, oral hygiene, frequency of food consumption, sugar consumption and fluoride sources are the variables that were shown to be highly correlated with caries risk.