The purpose of this study was to compare the profiles of transversal microradiography and nano-hardness with remarkably remineralized enamel lesions under conditions of non-fluoride. Furthermore, acid resistibility of remineralized enamel was investigated by Raman microspectroscopy. Demineralized bovine enamel was remineralized for 6 and 12 weeks, respectively. Remineralized enamel was immersed in a bufferd demineralizing solution for an acid resistance test. Transversal microradiographs were taken before and after the remineralization. Simultaneously, nano-indentation testing was performed across the lesion into the underlying sound enamel, starting from 10μm in from the anatomical surface at 10μm intervals. Remineralized and sound enamel were measured to determine the change in carbonate and phosphate from the anatomical surface at 10, 30 and 100μm by Raman microspectroscopy. After the 6-week reminelarization, the mineral vol% resulted in a pattern similar to that of a sound enamel profile. Mineral vol% of the 6 and 12 weeks remineralized surface and lesion bodies gave recoveries of up to 90%; however, recovery rates of the nano-hardness value were limited to 40-60%. The acid resistance test after the 6-week remineralization to a depth 70μm showed higher mineral vol% than demineralized sound enamel; however, the lesion around a depth of 75μm was less. Furthermore, after being remineralized for 12 weeks, a high mineral vol% was maintained compared with the demineralization of the sound demineralized enamel in the whole lesion. The Raman spectrum of the remineralized enamel lesion indicated the phosphate peak more intensively compared with sound enamel. These results indicated that recovery of mineral vol% reached the saturation point by remineralization after 6 weeks. However, the nano-hardness of the physical stability did not recover to the same degree as the mineral vol%. Therefore, these differences are thought to originate from the crystal formation and growth directions. The improvement of acid resistibility of the remineralized enamel is thus caused by the substitution of carbonate by phosphate in the crystals.

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Nowadays, halitosis has become a major problem in oral care. If the patients actually have a malodor, it is called genuine halitosis. On the other hand, if a psychological problem is the cause of the halitosis, it will be classified as a pseudo-halitosis or a halitophobia. We report herein on one case of a genuine halitosis patient. The 54-year-old female patient had been worried about her breath odor for about 20 years. Relatively strong malodor was detected and it was caused by periodontitis, tongue coating, deep caries, and unfitted restoration. The treatment was expected to take a long time, and we tried to give a precise explanation on future treatment and made an effort to keep the patient highly motivated. Due to such efforts, the treatment proceeded without trouble, and after completing the dental treatment, including periodontal, endodontic and prosthodontic treatment, almost no oral malodor was detected and the patient was satisfied with our treatment. In this way, proper diagnosis, proper dental treatment, and a good relationship between the patient and doctor are considered essential to the effective treatment of halitosis in patients.

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Cyclosporin A (CsA) is used widely as an immunosuppressive agent. CsA therapy induces several side effects such as nephrotoxicity, hepatoxicity, gingival overgrowth, and osteoporosis. Investigations of CsA-induced osteoporosis have been reported from clinical and basic aspects. Osteoporosis is recently thought to be one of the risk factors of periodontal disease, which is characterized by periodontopathic bacteria infection and alveolar bone loss. In this study, we investigated morphological changes of alveolar bone in CsA-treated rats. Fifteen-day-old rats were fed a powered diet containing or lacking CsA (50-200 mg/kg) for 8-30 days. On days 8, 16, and 30, they were sacrificed. After taking out the mandiblae, histomorphometric analyses were performed to examine morphorogic changes in the alveolar bone. The alveolar bone around the mesial root of the first molar were analysed using micro CT. The distance from the cement-enamel junction (CEJ) to the lingual alveolar bone crest (ABC) and the construction of the alveolar bone proper were measured by micro CT. Decalcified semi thin sections were stained with tartarte-resistant acid phosphatase (TRAP), and then histomorphometrical measurement was performed. The distance from CEJ to ABC was similar between CsA-treated and control rats. Micro CT analysis revealed that the volume and thickness of the alveolar bone in CsA-treated rats were decreased on days 16 and 30 compared with the controls. The ratio of bone surface to bone volume in CsA-treated rats was significantly increased on days 16 and 30. There was no difference in the number of osteoblasts and osteoclasts on the bone surface during experimental periods in both CsA-treated and control rats. The present study suggests that CsA administration may be a risk factor for periodontal disease progression, because CsA induced a decrease in alveolar bone volume and thickness.

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Adhesive technologies have recently become very popular in dental therapy for aesthetic, scientific, engineering, and other purposes. Along with this development, many clinical studies of the oral cavity using methodologies in vitro have revealed the importance of controlling humidity, since increased humidity reduces adhesive strength. However, the oral distribution of humidity has not been studied in detail and understanding of the effects of preventing moisture is limited. The present study focuses on intraoral temperature and humidity from the viewpoint of the oral environment to determine their distribution and the effects of air-blow and suction, which are essential for future mainstream clinical applications of adhesive substances. The present study targeted ten adults (five males and five females) of an average age of 31±4 years who had a healthy stomatognathic function. The Meikai University Ethics Committee approved the study protocol under Approval Number A0607. Sensors measured the temperature and humidity (THP-B4T, Shinyei Technology) and were coupled to a transmitter (THT-B121, Shinyei Technology). Data were collected in a recorder (midi Logger GL200, Graphtec) and examined using a PC with analytical software (midi Logger Software, Graphtec). Two experiments were conducted as part of this study as follows. Experiment 1: Intraoral temperature and humidity distribution. Humidity sensors were placed on the labial (buccal) and palatal side of the maxillary anterior teeth and molars to measure temperature and humidity after a period of stabilization. Experiment 2: Temperature and humidity changes induced in the oral cavity by blowing and sucking air. A sensor was placed on the buccal side of the maxillary first molar to measure the effects of blowing and sucking air for 5 to 10 seconds on temperature and humidity. Moisture was simultaneously prevented using a rubberdam, and temperature and humidity changes in the dam were also measured. Oral humidity increased towards the posterior regions, and temperature also increased. Relative humidity differed from absolute humidity. Although temperature and humidity decreased with the blowing and sucking the air, the effects were temporary, as they immediately increased once blowing and sucking of air was stopped. The temperature hardly changed after preventing moisture using the rubberdam, but humidity was significantly decreased and the effects were continuous and stable. Humidity levels differed regionally, and relative and absolute humidity values also differed. Our results thus indicated that the distribution of intraoral temperature and humidity differs throughout the oral cavity. Only the rubberdam could continuously prevent moisture, and temperature was largely affected by blowing and sucking air. Thus, absolute, rather than relative humidity was found to be a suitable index of humidity.

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We investigated the potential for detecting and evaluating red-fluorescent infected dentin using the quantitative light-induced fluorescence (QLF). The QLF examination of the digital image of red-fluorescent infected dentin was used to calculate the detected area, the average red-fluorescence intensity (ΔR average), and the maximum red-fluorescence intensity (ΔR Max) in three healthy volunteers who had dental caries. Red-fluorescence was observed at the same place where dental caries was diagnosed by X-ray examination. The ΔR Max values of each subject increased with the progression of dental caries excavation, and the ΔR Max value showed the maximum value when the infected dentin was exposed. Then, ΔR Max value decreased with the progression of the removal of the infected dentin. We concluded that the QLF method could be useful in the detection of hidden caries and evaluation of the progression of caries excavation.

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Temporary restorative materials for endodontic treatments should maintain a harmetic seal in the complex environment of the oral cavity. The purpose of this study was to compare the sealing ability of three calcium sulfate-based hydraulic temporary restorative materials (Cavit®, 3M ESPE; Caviton®, GC; and HY-Seal®, Shofu), a zinc oxide eugenol cement (Neodyne®, Neo Dental), a polymer-containing zinc oxide eugenol-based temporary restorative material (Eugemer®, Nihon Shika Yakuhin), and a zinc oxide non-eugenol cement (Canseal®, Showa Yakuhin Kako). The effect of intracanal medicaments on the sealing ability was also studied. Access cavities were prepared in extracted intact human molars (n=180), dressed with either a calcium hydroxide preparation (Calcipex II®, Nihon Shika Yakuhin) or FC (Formocresol "Murakami®", Agusa) and then restored with one of the six endodontic temporary restorative materials. The specimens were stored in distilled water for six days and then subjected to dye penetration tests under one of the three conditions (n=5, each):(A) immersion in 0.2% fuchsin solution; (B) thermal cycling followed by the dye immersion; and (C) thermal cycling followed by mechanical load cycling in the dye solution. Specimens were then sectioned buccolingually and the degree of dye penetration along the cavity wallmaterial interface was assessed using a stereomicroscope. Grading of the microleakage pattern was from 0 to 3, with 3 providing the worst seal. Data were statistically analyzed using Kruskal-Wallis ANOVA and multiple comparisons using the Dunn test (p<0.05). Under conditions (A) and (B), Neodyne® showed significantly higher degree of dye penetration compared with Canseal®, HY-Seal®, and Eugemer®. Under condition (C), however, Neodyne® and Canseal® showed significantly higher degree of dye penetration compared with HY-Seal®. No differences were detected between calcium hydroxide- and formocresol-dressed specimens. Within the limitation of the study, it can be concluded that HY-Seal® exhibited the best seal amongst the six materials tested.

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Lactoferrin (LF) is an iron-binding protein that is present in milk, and has a number of biological functions, including antimicrobial effects. In the present study, we evaluated the clinical, bacteriological, and biochemical changes that occur as a result of oral administration of bovine lactoferrin (bLF)-containing tablets, which were supplied by Morinaga Milk Industry, in periodontitis patients. After informed consent was obtained, 18 patients with mild chronic periodontitis were randomly selected for oral administration of tablets containing bLF (test group, 8 patients), or placebo tablets (control group, 10 patients). Oral administration of the two tablets was done three times a day for 3 months in a double-blind condition. The following measurements were recorded before and 1 week, 1 month and 3 months after the start of administration : 1) clinical periodontal conditions; 2) number of total bacteria, Porphyromonas gingivalis, and Prevotella intermedia in the subgingival plaque and saliva, as assessed by a quantitative polymerase chain reaction; 3) levels of human LF (hLF) and bLF in the gingival crevicular fluid (GCF) and saliva, as determined by a sandwich enzyme-linked immunsorbent assay; and 4) levels of endotoxin in GCF and saliva, as determined by a Limulus test. Differences in clinical, bacteriological, and biochemical changes between the two groups were assessed by the Mann-Whitney U test. No adverse effects were observed throughout the study period. In the test group, a significant reduction was seen in changes in the number of total bacteria (after 1 month), P. gingivalis (after 1 and 3 months), and P. intermedia (after 1 week) in the subgingival plaque, as compared to the control group. We also found a significant difference in GCF and saliva levels of bLF, but not in clinical measurements, saliva levels of bacteria, nor GCF and saliva levels of hLF and endotoxin between the two groups. Furthermore, a trend toward a reduction in GCF levels of hLF was observed in test group. This is the first report showing the antibacterial effects of orally administered bLF on subgingival flora in periodontitis patients, which might be partly supported by the relatively sufficient GCF levels of bLF. These results suggest that the antibacterial and food-component properties of oral bLF may contribute to the promotion of periodontal health.

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The purpose of this study was to investigate the effect of various reflective indexes on color changes of light-cured resin composites. Five experimental light-cured resin composites with the same shade, but had different reflectance indexes were used. Resin disks 8 mm in diameter by 1.0 mm in thicknesses were prepared. The colorimetric values of the specimens were measured immediately after curing against black and white backgrounds by a fast spectro-photometer (CMS-35FS/C, Murakami Shikisai). The appearance was characterized by means of the L* and C* value uniform CIE L*a*b* color system, and the total color difference (ΔE*ab value), translucency parameter (TP value), and opacity parameter (OP value) were calculated. The data was subjected to Duncan's test (α=0.05). The results were as follows. 1. L*value, C*value, ΔE*ab value, TP value, OP value, and the rate of spectral reflectance were affected by the refractive index of the experimental resins. 2. The L*value increased as the refractive index of the experimental resins increased. The C*value showed a different manner in background color that went down on a white plate and went up on a black plate. 3. ΔE*ab value tended to increase with an increase in the refractive index. This tendency was pronounced when the specimens were set on a black background. 4. When the differences in the refractive index between the matrix resin and filler decreased, the TP value was significantly higher than other experimental resins, and the TP value tended to decrease with an increase in the refractive index. 5. When the differences in the refractive index between the matrix resin and filler increased, the OP value was significantly higher, and the OP value tended to increase with an increase in the refractive index. 6. The spectrum reflectance tended to increase with an increase in the refractive index of the experimental resins. Spectrum reflectance tended to differ in shape with different background color, and high spectral reflectances in the higher wavelength region on the white plate, while the opposite results were obtained on the black plate.

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It has been so far clarified that caries is an endogenous disease due to carious pathogens represented by Streptococcus mutans (S. mutatis) and so on. With the growing recognition of the benefits to public health in recent years, natural foods are now highlighted with special reference to their effects on the human health in addition to their pharmacological actions. Japanese persimmons (Diospyros Kaki Thunb.) have been used as an herbal medicine in Japan with several biological activities, including antioxidant, anti-inflammatory and antimicrobial actions. In the present study, therefore, we focused on the components extracted from Kaki Calyx, a dried persimmon's calyx, which has been used as an anti-hiccup agent. The purpose of this study was to examine the antimicrobial actions of ursolic acid and oleanolic acid, both of which were extracted from Kaki Calyx, in an in vitro experiment in order to find a more efficient tool for the prevention of caries. The following conclusions were obtained. 1. The minimum inhibitory concentration against S. mutans was revealed to be 60μg/ml for ursolic acid and 120μg/ml for oleanolic acid. 2. The minimum inhibitory concentration against A. viscosus was revealed to be 30μg/ml for ursolic acid and 60μg/ml for oleanolic acid. 3. The antibacterial activities of ursolic and oleanolic acids were both found to have a bactericidal action against resting cells of S. mutans and A. viscosus. 4. Both ursolic and oleanolic acids markedly inhibited water insoluble glucan synthesis from sucrose by the crude glucosyltransferase of S. mutans PS-14(c). In conclusion, it was suggested that ursolic acid as well as oleanolic acid, both being a component extracted from Kaki Calyx, have antibacterial activity against cariogenic bacteria with an expected anti-carious effect.

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In recent years, an opaque resin, in which the colored cavity floor or lateral walls is successfully shielded and the translucent property of the overlaid resin composite is preserved as far as possible, has become available on the market, allowing more improved esthetic restoration. It is desirable for these opaque resins to have a hardness similar to that of resin composite with a color-shielding effect and translucent property as mentioned above. By focusing on the background color-shielding effect of zirconium (used as a filler) filled resin composite, its adaptability as an opaque resin was examined in order to obtain some basic information for predicting the background color shielding effect of the laminated resin composite. The color determination was performed by using a colorimeter of the contact type/three-stimuli directly reading-type, and the TP value of the sample used was calculated from the L*a*b* value obtained by using black and white boards as background color. In addition, the utility of the opaque resin was examined by referring to the TP values according to the varied amount of zirconium filler used as well as the varied thickness of the sample taken in order to estimate the TP value when a sample of commercially available resin composite was overlaid. Based on the TP values thus estimated, a possible method for predicting TP values when a sample of this opaque resin was filled with a sample of resin composite was further investigated. In consequence, the following conclusions could be drawn from the experimental results mentioned above. 1. It was confirmed that the zirconium filler used in this experiment possesses a background color shielding effect with confirmed adaptability as opaque resin filler. 2. Although the resin composite itself has a background color shielding effect, it was also suggested that the background color may be influenced by the 3.0 mm thickness of the sample used. Furthermore, the TP values seemed to have changed in response to the pigments used. 3. In case of resin composite samples B2 and A4 under the present experimental conditions, TP values of ≦ 2.0 were attained successfully by setting the size of the 6% zirconium-filled opaque resin sample at 1.0 mm thickness and by overlaying the resin composite sample at 2.0 mm thickness. 4. From the TP values of the opaque resin sample and resin composite as well as the difference in the background color, a calculation formula which makes it possible to predict the TP values of the laminated sample was successfully presented.

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In everyday clinical settings, apical periodontitis often causes persistent pain even after local inflammation has been resolved. This symptom is considered to be caused by sensory nerve fibers in the periodontal ligament, which is a sensory receptor on the root surface, and sympathetic nerve endings originating from the superior cervical ganglia. The present study investigated the involvement of sensory and sympathetic nerves surrounding the periapical tissue in apical periodontitis. Rat models of apical periodontitis were created and perfusion-fixed, followed by removal of the mandible and preparation of frozen sections. Frozen sections underwent hematoxylin-eosin (HE) staining. An immunohistochemical staining method was used to detect calcitonin gene-related peptide (CGRP) in sensory nerves and tyrosine hydroxylase (TH), the catecholamine synthesis rate-limiting enzyme, in sympathetic nerves. Semi-quantitative image analysis was conducted for nerve fibers showing a positive immunoreaction for CGRP and TH. HE staining of the periapical tissue with pulpal infection revealed an enlarged periodontal space and increase in inflammatory cells, suggesting apical periodontitis. The inflamed periodontal ligament showed an increase in the immunoreaction for CGRP and TH, and a significant increase in the stain intensity for CGRP and TH (p<0.05), compared to the normal periodontal ligament. These results suggested that CGRP immunoreactive sensory nerves in the periodontal ligament and TH immuroreactive sympathetic nerves are involved in the persistent pain and inflammation associated with apical periodontitis.

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Glycyrrhetinic acid, the extract of Glycyrrhiza globra (licorice), is known to have various pharmacological effects such as anti-inflammatory and anti-allergic activities. However, there is no report that investigates the inhibitory effects of glycyrrhetinic acid on inflammatory bone resorption. In the present study, we examined the effects of glycyrrhetinic acid on inflammation of gingival connective tissue and alveolar bone resorption induced by lipopolysaccharide (LPS) injections into BALB/c mice gingiva. Repeated injections of 5μg of Escherichia coli (E. coli) LPS caused inflammatory cell infiltration and osteoclastic bone resorption. Administration of 1% glycyrrhetinic acid significantly reduced the LPS-induced osteoclast formation. Additionally, we also examined changes in the number of interleukin (IL)-1β- and receptor activator of NF-κB ligand (RANKL)-positive cells in gingival connective tissue. Glycyrrhetinic acid significantly decreased the number of IL-1β- and RANKL-positive cells induced by LPS. These results suggest that glycyrrhetinic acid inhibits LPS-induced bone resorption and that the suppression of IL-1β and RANKL production may be involved in the inhibitory effects.

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Vital teeth bleaching is a method of achieving esthetically whiter teeth, and has been recognized as a relatively low-cost, conservative and noninvasive treatment. However, a certain percentage of patients will experience tooth sensitivity during the bleaching procedure. This study examined the effect of the combined use of a desensitizer and bleaching agents. Thirty-nine extracted human teeth were used. The MS Coat™ (Sun Medical, "MS-C") was used as a desensitizer. Shofu Hi-Lite™ (Shofu, "HL") and Nite White Excel™ (Discuss Dental, USA, "NWE") were used as bleaching agents. Twenty-two teeth were cut in half and used to examine the effect on changes in the enamel surface color by the combined use of bleaching agents and desensitizer. Tooth color was measured with a colorimeter Shade Eye NCC (Shofu). Penetrating effect into the tooth was also examined. Twelve teeth were cut in half and the sectioned surface glued to slide glass. Each sectioned surface was photographed and digitized; color changes were determined by Adobe Photoshop CS image analyzing software, calculating the color difference ΔE* value from CIE L*a*b* values. Bleaching groups were (1) MS-C plus HL bleaching, (2) HL bleaching, (3) MS-C plus NWE bleaching, and (4) NWE bleaching. SEM observations were done on the remaining five teeth before and after procedures. The clinical effect of the desensitizer was examined. Eight volunteer patients were involved in the sprit test, i. e. maxillary right anterior teeth were controls, while the left anterior teeth were MS-C coated and bleached by NWE. The results were as follows. No difference in the effect between bleaching with HL alone and bleaching with HL plus MS-C was found. When NWE was used with MS-C, the bleaching effect was reduced to approximately three quarters compared to without MS-C. The bleach agent penetrates into the tooth structure to develop the bleaching effect. SEM photographs revealed HL bleach peeled off the MS-C, whereas NWE damaged the MS-C film less. This confirmed that the HL bleach effect did not change in combination with MS-C. The effect of NWE bleach was not completely reduced in combined use. In the clinic, clear bleaching effect and reduced tooth sensitivity were observed, supporting the conclusion that a combined use of NWE and MS-C is effective in suppressing tooth sensitivity. In many cases, shortening the treatment time or skipping treatments were effective. However, this study suggests that the combined use of a desensitizer with bleach agents might be effective in suppressing intense tooth sensitivity.

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Objective: To develop a predictive equation to screen vertical root fractures (VRFs) by numerically evaluating the shapes of lesion areas on cone-beam X-ray CT (3DX multi Image Micro CT® : 3DX, Morita) of endodontically treated maxillary incisors and premolars. Methods: Thirty preoperative 3DX sagital images of incisors and premolars with lesion areas including root apices were selected and examined for this study. Out of 30 teeth, 15 had a fractured root (VRF group), and 15 had a nonfractured root (non-VRF group). A periapical lesion area of each tooth was traced out by five examiners on a personal computer, and two indices, "Complexity" and "Radial SD", were measured. For each index, the difference between the VRF and non-VRF groups and the inter-examiner differences were analyzed with a two-way ANOVA at 5% significance level. Multiple logistic regression analysis was used to develop a predictive equation, and the probability of VRF for all samples was calculated. A receiver operating characteristic (ROC) curve was constructed to select the optimal cut point. Each sample was predicted as 'VRF' or 'non-VRF' with this cut point. Results: For both "Complexity" and "Radial SD", the VRF group showed significantly greater values than the non-VRF group (p<0.05). With a cut point derived from the ROC curve, sensitivity, specificity, and overall accuracy of this logistic model for VRF were 0.89, 0.87, and 0.88, respectively. Conclusions: VRF teeth have more complicated lesion areas compared to non-VRF teeth on 3DX. By evaluating the shapes of lesion areas, a logistic regression equation to screen VRF was calculated, and results suggest that this equation could contribute to the diagnosis of VRF.

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The objective of the present study was to examine the color of cavities before and after caries removal. In recent years, the demand for esthetic repair has increased, and composite resin restoration is being performed more often. As semitransparent materials are used in composite resin restorations, the color of discolored dentin affects the outcomes achieved. In clinical settings, as discolored dentin is not completely removed in some cases to protect the dentin, the color of the composite resin that is selected using a shade guide does not match the color of the surrounding dentin. In this manner, the color of carious dentin plays an important role in the color compatibility of composite resin. We measured the color of cavities in 9 men and 10 women ranging from 28 to 83 years of age who visited Meikai University Hospital. Color was measured for a total of 46 teeth: 25 maxillary and 21 mandibular anterior teeth and first premolars with caries at one-third the dental cervix. In order to identify the correct color of cavities before and after caries removal, Casmatch (a color chart, Kyowa Tokei Kogyo) was placed near each tooth. Photographs were taken using a digital camera, and measurements were made using a computer. Whether caries were successfully removed or not was determined based on general techniques such as staining using a caries detector or dentin hardness assessment by palpitation. The results showed that the L* value of all teeth was significantly higher after caries removal. Color difference between before and after caries removal was determined and the standards defined by Gross et al. were applied. The color difference of all teeth was ≧2.0, revealing a visually discernible difference. The other results showed that the L* value of all teeth was lower than natural dentin. These results suggest that the restoration materials having a property to cover a background color should be used in combination when repairing esthetically.

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The purpose of this study was to investigate the effect of thermal cycling on the surface texture of resin composite. The polishing system used consisted of a Super-Snap (Shofu) to prepare the surface of polymerized resin blocks of six different light-cured resin composites: Beautifil II (Shofu), Gradia Direct (GC), Clearfil Majesty (Kuraray Medical), Filtek Supreme XT (3M ESPE), Palfique Estelite Σ (Tokuyama Dental), and Estelite Σ Quick (Tokuyama Dental). Silicon carbide paper (#400) was selected to obtain the surface roughness of the specimens countered with a super-fine diamond point. Polishing was done with Super-Snap green for 15 seconds followed Super-Snap red for 15 seconds at 10,000 rpm, respectively, under a loading force of 0.5N. The surface roughness and surface gloss of the polished specimens were determined by a surface recorder (SE-30H, Kosaka Lab.) and a gloss meter (GM-26D, Murakami Color Research Lab.). Changes in color were measured using a spectro photometer (Spectro-Photo Meter CMS-35FS/C, Murakami Color Research Lab.) and evaluated by the CIE 1976 L*a*b*. Evaluations were performed immediately after the polishing and after 10,000 thermal cycles. Specimens were examined immediately after polishing and after 1,000, 3,000 and 10,000 thermal cycles, respectively, with scanning electron microscopy. The results were as follows. 1. No changes in the surface roughness of the resin composite regardless of the number of thermal cycles applied were observed. 2. No changes in the surface gloss of Gradia Direct, Palfique Estelite Σ and Estelite Σ Quick after 10,000 thermal cycles were observed. 3. Color changes in the resin composites after thermal cycling were observed. 4. Palfique Estelite Σ and Estelite Σ Quick produced smoother surfaces than other resin composites after 10,000 thermal cycles.

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