Microtensile bond strength of root canal dentin treated with adhesive and fiber-reinforced post systems.

Nowadays, demand for esthetic restorations has risen considerably; thus, nonmetal esthetic posts made of either high-strength ceramics or reinforced resins, such as fiber-reinforced resin posts, have become more and more popular. Important characteristics of fiber-reinforced posts involve a modulus of elasticity similar to dentin and their ability to be cemented by an adhesive technique. A total of 36 maxillary incisors were divided into four groups. In this study, four adhesively luted fiber-reinforced (glass fiber, quartz glass fiber, zirconia glass fiber and woven polyethylene fiber ribbon) post systems were used. Post spaces were prepared by employing drills according to the protocol established for each group, and each post was adhesively luted with one of three adhesive systems. Three segments per root apical to the cementoenamel junction (CEJ) were obtained by sectioning the root under distilled water with a carbon spare saw. The samples (total of 108 sections) were 2.0±0.1 mm in thickness and they were stored individually in black film canisters with sterile distilled water. In order to determine the bond strength, the bonding area of each specimen was measured, and specimens were attached to a device to test microtensile strength at a speed of 1 mm/min. The analyses revealed no statistically significant differences between the adhesive systems and fiber-reinforced posts. (P> 0.05). However, the coronal portion of the root dentin had the highest bond strength. Adhesive systems used along with fiber-reinforced resin posts demonstrated reliable bonding.

Microtensile bond strength of root canal dentin treated with adhesive and fiber-reinforced post systems

Abstract Nowadays, demand for esthetic restorations has risen considerably; thus, nonmetal esthetic posts made of either high-strength ceramics or reinforced resins, such as fiber-reinforced resin posts, have become more and more popular. Important characteristics of fiber-reinforced posts involve a modulus of elasticity similar to dentin and their ability to be cemented by an adhesive technique. A total of 36 maxillary incisors were divided into four groups. In this study, four adhesively luted fiber-reinforced (glass fiber, quartz glass fiber, zirconia glass fiber and woven polyethylene fiber ribbon) post systems were used. Post spaces were prepared by employing drills according to the protocol established for each group, and each post was adhesively luted with one of three adhesive systems. Three segments per root apical to the cementoenamel junction (CEJ) were obtained by sectioning the root under distilled water with a carbon spare saw. The samples (total of 108 sections) were 2.0±0.1 mm in thickness and they were stored individually in black film canisters with sterile distilled water. In order to determine the bond strength, the bonding area of each specimen was measured, and specimens were attached to a device to test microtensile strength at a speed of 1 mm/min. The analyses revealed no statistically significant differences between the adhesive systems and fiber-reinforced posts. (P> 0.05). However, the coronal portion of the root dentin had the highest bond strength. Adhesive systems used along with fiber-reinforced resin posts demonstrated reliable bonding.

Comparison of Forsus FRD EZ and Andresen activator in the treatment of class II, division 1 malocclusions.

OBJECTIVES: Purpose of this study is to evaluate the effects of Forsus Fatigue-Resistant Device (FRD) EZ and Andresen activator in terms of skeletal, dental, and soft tissue changes in actively growing patients presenting with class II, division 1 malocclusion. MATERIALS AND METHODS: Study sample included 60 subjects. Inclusion criteria were as follows: class II division 1 malocclusion, retrognathic mandible, normal or low-angle growth pattern, and peak growth period. The first study group consisted of 20 patients who were treated with Forsus appliance, and the second group of 20 patients received treatment with Andresen activator. Control group received no treatment. RESULTS: Our results revealed that both appliances enhanced mandibular growth, helped increase the length of the mandible, and had a restraining growth effect on the maxilla. Anterior face height increased in both of treatment groups, whereas posterior face height had a significant increase in the activator group only. More mandibular incisors protrusion and intrusion were seen with the Forsus appliance. Moreover, occlusal plane and palatal plane rotated significantly in clockwise direction as a result of dentoalveolar changes only in the Forsus group. CONCLUSIONS: As well as the Forsus appliances corrected class II discrepancies mostly through dentoalveolar changes as compared to the activator group, both appliances proved effective in the treatment of growing individuals having class II malocclusions with mandibular retrognathia. CLINICAL RELEVANCE: By this investigation, two treatment methods, which are currently used in clinical practice, will be evaluated, and the results will be useful for clinicians.

Orthognathic surgical planning on three-dimensional stereolithographic biomodel.

The aim of this report was to present the orthognathic surgical planning of a patient with maxillary retrusion, mandibular prognathism, and midline shift on a three-dimensional stereolithographic biomodel. A patient who complained about facial deformity and difficulty in chewing was referred to our department. After a short-term presurgical orthodontic treatment, Le Fort I osteotomy and bilateral sagittal split ramus osteotomy were performed. Triangular axial gaps occurred anteriorly and posteriorly between the proximal and distal segments of the osteotomized mandible. These gaps were filled with bone grafts in accordance with templates that were constructed on a three-dimensional stereolithographic biomodel. Rotational movement of the distal mandibular segment around the y axis caused axial triangular gapping between the proximal and distal mandibular segments. In the presented case, orthognathic surgical planning was performed on the three-dimensional solid models, and templates were reconstructed according to these gaps. These templates were used to determine the size of the bone grafts during the surgical approach. The patient was diagnosed with lateral cephalometric and posteroanterior cephalometric analysis in postretention for 2 years, and it was determined that long-term results were perfect and skeletal relapse did not occur after 2.5 years of surgery. Movement at the site of the osteotomy is usually the main cause of relapse after orthognathic surgery. In the presented case, a three-dimensional stereolithographic biomodel was used to plan the orthognathic surgery and to reconstruct the templates to determine the size and shape of the bone grafts. Using bone grafts established close contact between proximal and distal osteotomized bone segments, enhanced bone healing, and diminished relapse risk.

Shear bond strength of bonding to enamel with different laser irradiation distances.

The aim of this study was to investigate the shear bond strength of bonding to enamel following laser etching with the Er:YAG or Er,Cr:YSGG laser using different irradiation distances. Of 99 extracted human premolar teeth, 90 were divided equally into nine groups. In the control group (group A) the teeth were etched with 38% phosphoric acid. In the laser groups (groups B-I) the enamel surface of the teeth was laser-irradiated, groups B-E with the Er:YAG laser and groups F-I with the Er,Cr:YSGG laser at distances of 1, 2, 4 and 6 mm, respectively. The shear bond strengths were tested using a universal testing machine. The shear bond strengths associated with the Er:YAG laser at 4 and 6 mm and the Er,Cr:YSGG laser at 2, 4 and 6 mm were significantly less than the strengths obtained with the other irradiation distances (p<0.001). The Er:YAG laser at 1 mm and the Er,Cr:YSGG laser at 1 mm etched enamel in the same manner (p>0.05). This finding was confirmed by scanning electron microscopy examination. Irradiation distance did influence the strength of adhesion to enamel. The mean shear bond strengths and enamel surface etching obtained with the Er:YAG laser at 1 and 2 mm and the Er,Cr:YSGG laser at 1 mm were comparable to that obtained with acid etching.

Influence of different power outputs of erbium, chromium:yttrium-scandium-gallium-garnet laser and acid etching on shear bond strengths of a dual-cure resin cement to enamel.

The purpose of the study was to determine if the irradiation of enamel with laser of different output powers might be viable alternatives to acid etching for the bonding of resin luting agents. Seventy-seven maxillary central incisors, extracted for periodontal reasons, were used. The enamel was etched with an erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser operated at one of six power outputs (0.5 W, 0.75 W, 1 W, 1.5 W, 1.75 W and 2 W) or with 38% phosphoric acid. Seventy teeth were used for the bond strength experiments, and the remaining seven (one specimen for each group) were used for scanning electron microscopy (SEM) to determine the topography and morphology of the treated enamel surface. The acid-etched group yielded the highest mean of shear bond strength (13.5 ± 2.8 MPa). The means of the shear bond strength for the teeth irradiated at 0.5 W, 0.75 W, 1 W, 1.5 W , 1.75 W and 2 W laser were 3.28 ± 2.4 MPa, 5.44 ± 3.4 MPa, 8.8 ± 4.5 MPa, 10.2 ± 4.0 MPa, 11.4 ± 4.8 MPa and 11.9 ± 4.3 MPa, respectively. Laser irradiation at 1.5 W, 1.75 W and 2 W produced a type III acid-etched pattern similar to that produced by acid etching. No significant enamel surface etching was obtained by 0.5 W or 0.75 W laser irradiation. Irradiation at 0.5 W and 0.75 W produced a type V acid-etched pattern. We concluded that the mean shear bond strength and enamel surface etching obtained with Er,Cr:YSGG laser (operated at 1.5 W and 1.75 W for 15 s) is comparable to that obtained with acid etching.

Comparison of the effects of fixed and removable functional appliances on the skeletal and dentoalveolar structures.

OBJECTIVE: To compare and analyse the effects of activator and Forsus FRD EZ appliances in the treatment of skeletal Class II division I malocclusion. METHODS: Lateral cephalograms and hand-wrist radiographs were collected from 24 Class II division I growing patients (14 females, 10 males). The patients were randomly divided into two equal groups and either treated with an activator appliance (Mean age 12.67 +/- 1.24 years) or with a Forsus FRD EZ appliance (Mean age 12.31 +/- 1.09 years). Pretreatment and posttreatment cephalometric radiographs were obtained, traced, superimposed and data analysed using paired t-tests and the Wilcoxon signed rank test. RESULTS: The results demonstrated that the Forsus FRD EZ effectively corrected the Class II malocclusion, but the changes were mainly dentoalveolar. The Forsus FRD EZ appliance induced a clockwise rotation of the occlusal plane without significant alteration in the vertical facial dimension. Skeletally, maxillary growth was restricted and pogonion moved forward which improved the profile. CONCLUSION: The Forsus FRD EZ appliance may be an effective dentoalveolar treatment method to manage a skeletal imbalance and improve the profile in growing patients.

Surface roughness of the restored enamel after orthodontic treatment.

INTRODUCTION: After fixed appliance treatment, one concern is to restore the enamel surface as closely to its original state as possible. A variety of cleanup processes are available, but all are time-consuming and carry some risk of enamel damage. The purpose of this study was to examine tooth surfaces restored with different cleanup protocols. METHODS: Ninety-nine premolars extracted for orthodontic purposes were used. The 2 materials tested were Sof-Lex disks (3 M ESPE AG, Seefeld, Germany) and fiberglass burs (Stain Buster, Carbotech, Ganges, France). These were used alone and in combination with high- and low-speed handpieces, with which they were also compared. Eight groups were ultimately tested. All groups were compared with intact enamel, which served as the control group. From each group, 10 samples were examined with profilometry and 1 with scanning electron microscopy. Adhesive remnant index scores were recorded to ensure equal distributions for the groups. The time required for the cleanup processes and profilometry test results were also recorded. RESULTS: The fastest procedure was performed with high-speed handpieces, followed by low-speed handpieces. Sof-Lex disks and fiberglass burs required more time than carbide burs but did not result in significantly longer times for the cleanup procedure when combined with tungsten carbide-driven low- or high-speed handpieces or when used alone with low-speed handpieces. Although Sof-Lex disks were the most successful for restoring the enamel, it was not necessary to restore the enamel to its original surface condition. Generally, all enamel surface-roughness parameters were increased when compared with the values of intact enamel. The average roughness and maximum roughness depth measurements with Sof-Lex disks were statistically similar to measurements of intact enamel. CONCLUSIONS: No cleanup procedure used in this study restored the enamel to its original roughness. The most successful was Sof-Lex disks, which restored the enamel closer to its original roughness.

In vitro evaluation of microleakage under orthodontic brackets using two different laser etching, self etching and acid etching methods.

This study evaluated the microleakage of brackets bonded by four different enamel etching techniques. Forty freshly extracted human premolars were divided randomly into four equal groups and received the following treatment: group 1, acid etching; group 2, self-etching primer (SEP); group 3, erbium:yttrium-aluminum-garnet (Er:YAG) laser etching; and group 4, erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser etching. After photopolymerization, the teeth were kept in distilled water for 1 month and then subjected to 500 thermal cycles. Then, the specimens were sealed with nail varnish, stained with 0.5% basic fuchsin for 24 h, sectioned, and examined under a stereomicroscope. In addition, they were scored for marginal microleakage at the adhesive-enamel and bracket-adhesive interfaces from the incisal and gingival margins. Statistical analyses consisted of the Kruskal-Wallis test and the Mann-Whitney U test with Bonferroni correction. Microleakage occurred between the adhesive-enamel and bracket-adhesive interfaces in all groups. For the adhesive-enamel surface, a significant difference was observed between group 1 and groups 2 (P = 0.011), 3 (P = 0.002), and 4 (P = 0.000) on the gingival side. Overall, significant differences were observed between group 1 and groups 3 (P = 0.003) and 4 (P = 0.000). In dental bonding procedures, acid etching was found to result in the least microleakage. Since etching with a laser decreases the risk of caries and is time-saving, it may serve as an alternative to acid etching.

Noncompliance therapy: Veltri appliance.

AIM: To achieve intraoral molar distalization without any extraoral appliance or patient cooperation. METHODS: The intraoral distalization technique was performed on a female 12 years 8 months of age with cooperation deficiency, and the positive results are presented. The patient initially accepted the headgear planned at the beginning of treatment, but she did not wear it long enough. We therefore abandoned the use of extraoral appliances and employed intraoral distalization instead. We preferred to use a Nance button Veltri appliance we could create in our clinic. Once the patient had accepted our new treatment plan, we completed the distalization process in about 2 months. After a 2-month retention period, we completed treatment with a fixed Roth edgewise appliance and maximum anchorage in the maxilla for approximately 18 months. RESULTS: Following treatment, a Class II Division I dental relationship became a Class I relationship in both the canine and molar regions, and a functional occlusal relationship and esthetic facial appearance were obtained. CONCLUSION: This appliance can be used when patient cooperation is compromised.

Comparison of a recently developed nanofiller self-etching primer adhesive with other self-etching primers and conventional acid etching.

The purpose of this ex vivo study was to compare the bond strengths and modes of failure of brackets bonded with three self-etching products [Adper Prompt L-Pop (3M Espe), Futurabond NR (Voco) and Transbond Plus (3M Unitek)] and a conventional 38 per cent phosphoric acid-etching system Etch-Rite (Pulpdent Corp.) at two different time points. Ninety-six defect-free premolars were randomly allocated to eight groups (n = 12). The etching procedure was carried out according to the manufacturers' instructions. The shear bond strengths (SBSs) were measured after storage in distilled water for 12 and 24 hours. The brackets were debonded using a universal testing machine with a cross-head speed of 0.5 mm/minute. Multiple comparisons of the SBSs for the different etching types were performed using analysis of variance. The chi-square test was used to evaluate differences in adhesive remnant index (CARI) scores among the groups. The differences between SBSs analysed at 12 and 24 hours were not significantly different. Although a significant difference (P < 0.01) was observed with conventional and self-etching primer (SEP) adhesive systems, SEP revealed bond strengths higher than clinically accepted limits (6-8 MPa). SEP systems can achieve successful orthodontic bond strengths. The rate of development of the bond strength must be determined to ensure sufficient maturation of orthodontic adhesives before functional loading.

Dental Aesthetic Index scores and perception of personal dental appearance among Turkish university students.

The aim of this study was to investigate the relationship between Turkish university students' awareness of malocclusion, their satisfaction with their personal dental appearance, and the severity of their occlusal irregularities. The sample consisted of 841 randomly selected university students, 522 (62.1 per cent) males and 319 (37.9 per cent) females, aged 17-26 years (mean age, 21.91+/-1.92 years). A pre-tested questionnaire was used to assess the subjects' awareness of malocclusion and satisfaction with their personal dental appearance; the actual severity of malocclusion was determined using the Dental Aesthetic Index (DAI). Statistical analysis was carried out using chi-square for gender differences and Spearman rank-order correlation coefficients for awareness of malocclusion, satisfaction with personal dental appearance, and DAI scores. Analysis of variance and univariate analysis, with age and gender as the independent variables, were further used to analyse the data. Weak but statistically significant, negative, correlations were found between awareness of malocclusion and satisfaction at the following DAI scores: or= 36 (r= -0.477, P<0.001), and a statistically insignificant, negative correlation at a score of 31-35 (r= -0.102, P>0.05). A statistically significant association was found between DAI and awareness of malocclusion (r= -0.305) and satisfaction with dental appearance (r=0.234). There were no significant associations between the department in which the individuals studied and the investigated variables (P>0.05). DAI scores were significantly higher for females. Generally, no statistically significant gender differences were found in relation to DAI scores, awareness, or satisfaction (P>0.05). The findings of this study showed that age had a significant effect on satisfaction and gender on DAI score variation. Females had a greater need for normative treatment except in the 20- to 22-year-olds, and satisfaction decreased with age.

Laser etching of enamel for orthodontic bonding.

INTRODUCTION: The purposes of this study were to assess the shear bond strength, the surface characteristics, and the adhesive remnant index scores of teeth prepared for bonding with erbium, chromium doped: yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser etching, and to compare laser etching with phosphoric-acid etching and a self-etching primer. METHODS: Sixty-four premolars, extracted for orthodontic purposes, were randomly divided into 4 groups, and a different method was used to prepare the tooth enamel in each group for bonding: irradiation for 15 seconds with a 0.75-W Er,Cr:YSGG laser; irradiation for 15 seconds with a 1.5-W Er,Cr:YSGG laser; etching with 37% phosphoric acid; application of a self-etching primer. After surface preparation, standard edgewise stainless steel premolar brackets were bonded; 1 tooth in each group was not bonded and was examined under a scanning electron microscopic. The brackets were debonded 24 hours later; shear bond strengths were measured, and adhesive remnant index scores were recorded. RESULTS: Irradiation with the 0.75-W laser produced lower shear bond strengths than the other methods. No statistically significant differences were found between 1.5-W laser irradiation, phosphoric-acid etching, and self-etching primer. Adhesive remnant scores were compared with the chi-square test, and statistically significant differences were found between all groups; when the 0.75-W laser irradiation group was excluded, no statistically significant differences were observed. CONCLUSIONS: Irradiation with a 1.50-W laser produced sufficient etching for orthodontic bonding, but irradiation with the 0.75-W laser did not.

Nonsurgical orthodontic treatment of an adolescent girl with Class III malocclusion and asymmetric maxillary narrowing.

Class III malocclusion is a difficult anomaly to understand. Because not all Class III patients are candidates for surgical correction, patient assessment and selection are especially important in diagnosis and treatment planning. In this article, we report the orthopedic treatment of a teenage girl with a severe skeletal Class III malocclusion. Her ANB angle was -4.5 degrees, and she had a 2-mm anterior crossbite, a 1-mm overbite, and a posterior asymmetric crossbite (greater on the left side). The patient refused surgery. We used a rapid palatal expansion appliance to expand the maxilla, standard edgewise brackets to align the teeth, and reverse headgear to bring the maxilla forward. We performed symmetric expansion, but, because of the asymmetric crossbite in the maxilla, we designed a modified apparatus that permitted greater relapse on 1 side. In this way, the posterior crossbite was ideally corrected by the end of treatment, and ideal overjet and overbite relationships, functional occlusion, and an esthetic facial appearance were all achieved.

Comparison of sandblasting, laser irradiation, and conventional acid etching for orthodontic bonding of molar tubes.

The purpose of the study was to determine if sandblasted and laser-irradiated enamel may be viable alternatives to acid etching for molar tube bonding. Seventy-seven molar teeth extracted for periodontal reasons were used. Seventy teeth underwent shear bond strength (SBS) testing and the remaining seven were examined under scanning electron microscopy (SEM). Adhesive remnant index (ARI) scores were also considered. An erbium, chromium-doped:yttrium-scandium-gallium-garnet (Er, Cr: YSGG) laser was used for enamel etching. Sandblasted and laser-irradiated enamel surfaces with different power outputs (0.5, 0.75, 1, 1.5, and 2 W) were compared with conventional phosphoric acid etching. Descriptive statistics, including mean, standard deviation, and minimum and maximum values, were calculated for each group. Multiple comparisons of the SBS of different etching types were performed by analysis of variance testing. The chi-square test was used to evaluate differences in ARI scores between groups. Acid-etched, 1-, 1.5-, and 2-W laser irradiation groups demonstrated a clinically acceptable mean SBS (7.65 +/- 1.38, 6.69 +/- 1.27, 7.13 +/- 1.67, 7.17 +/- 1.69 MPa, respectively). Irradiation with an output of 0.5 and 0.75 W and sandblasting of the enamel showed a lower SBS than the other groups (2.94 +/- 1.98, 4.16 +/- 2.87, 2.01 +/- 0.64 MPa, respectively). SEM evaluation of 1, 1.5, and 2 W laser irradiation revealed similar etching patterns to acid etching. Sandblasting and 0.5, and 0.75 W laser etching were not able to etch enamel in preferential patterns. Laser irradiation at 1.5 and 2 W was able to etch enamel. More adhesive was left on the enamel surface with low-power laser irradiation. Sandblasting and low-power laser irradiation (0.5, 0.75, and 1 W) are not capable of etching enamel suitable for orthodontic molar tube bonding, but 1.5- and 2-W laser irradiation may be an alternative to conventional acid etching.

One of the rarest syndromes in dentistry: gardner syndrome.

Gardner syndrome is a rare, autosomal dominant syndrome. It will follow a positive course with diagnosis and treatment by medical and dental specialists. Orthodontists or general dental physicians can easily diagnose the syndrome through radiological images taken in addition to dental and skeletal findings. The aim of this study was therefore to report two cases of this syndrome and to evaluate it from an orthodontic perspective in order to attract the attention of orthodontists to this rare anomaly.

Comparision of dental arch widths in different types of malocclusions.

AIMS: To compare dental arch and alveolar widths of patients with Class III and Class II division 1 malocclusions and those with Class I ideal occlusion. METHODS: Ninety patients were classified in 3 groups of 30 (15 male and 15 female) according to molar relationship. No subjects had received orthodontic treatment, and in all patients, the primary teeth had completely exfoliated. Dental casts of the 90 subjects were made and photographed with a digital camera on a tripod. Dental cast measurements were taken with a dial caliper to the nearest 0.01 mm. All measurements of all subjects were carried out again 2 weeks later to evaluate the measurement error. RESULTS: Analyses of 1-way analysis of variance demonstrated that (1) there were statistical differences in most of the measurements between the Class I and Class III groups (P>.05) and (2) the Class II division 1 group had differences from other groups (P<.05). This result suggests that transverse discrepancy in Class II division 1 and Class III patients may originate from the maxillary posterior teeth. CONCLUSION: Maxillary intermolar widths are significantly greatest in Class III, Class I, and Class II division 1 groups, respectively.

Cervical vertebral and dental maturity in Turkish subjects.

INTRODUCTION: The aim of this study was to investigate the relationships between the stages of calcification of teeth and the cervical vertebral maturity stages in Turkish subjects. METHODS: A retrospective cross-sectional study was designed. The final study population consisted of 590 Turkish subjects. Statistical analysis of the data was performed with computer software. Spearman rank order correlation coefficients were used to assess the relationship between cervical vertebral and dental maturation. For a better understanding of the relationship between cervical vertebral maturation indexes and dental age, percentage distributions of the studied teeth were also calculated. RESULTS: Strict correlations were found between dental and cervical vertebral maturation of Turkish subjects. For males, the sequence from lowest to the highest was third molar, central incisor, canine, first premolar, second premolar, first molar, and second molar. For females, the sequence from lowest to the highest was third molar, canine, second premolar, first premolar, central incisor, first molar, and second molar. CONCLUSIONS: Dental maturation stages can be used as a reliable indicator of facial growth.

Etching enamel for orthodontics with an erbium, chromium:yttrium-scandium-gallium-garnet laser system.

OBJECTIVE: To test the shear bond strength, surface characteristics, and fracture mode of brackets that are bonded to enamel etched with an erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser operated at different power outputs: 0.5 W, 1 W, and 2 W. MATERIALS AND METHODS: Human premolars that had been extracted for orthodontic purposes were used. Enamel was etched with an Er,Cr:YSGG laser system operated at one of three power outputs or with orthophosphoric acid. RESULTS: The shear bond strength associated with the 0.5-W laser irradiation was significantly less than the strengths obtained with the other irradiations. Both the 1-W and 2-W laser irradiations were capable of etching enamel in the same manner. This finding was confirmed by scanning electron microscopy examination. The evaluation of adhesive-remnant-index scores demonstrated no statistically significant difference in bond failure site among the groups, except for the 0.5-W laser-etched group. Generally, more adhesive was left on the enamel surface with laser irradiation than with acid etching. CONCLUSION: The mean shear bond strength and enamel surface etching obtained with an Er,Cr: YSGG laser (operated at 1 W or 2 W for 15 seconds) is comparable to that obtained with acid etching.

Interleukine-1beta and tumor necrosis factor-alpha levels in the human gingival sulcus during orthodontic treatment.

OBJECTIVE: To test whether interleukine 1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) levels differ from each other in different treatment levels. MATERIALS AND METHODS: Eighteen patients, nine female and nine male (aged 16-19 years; mean 17.4 +/- 1.8 years), participated in this study. Each subject underwent a session on professional oral hygiene and received oral hygiene instructions. Two months later, a fixed orthodontic appliance was placed. The patients were seen at baseline, at days 7 and 21 and at the 3rd and 6th month as the leveling of the teeth occurred. Records of the baseline scores for the distalization forces were taken at the 6th month. Days 7 and 21 after 6 months of treatment were also recorded. RESULTS: There were increases in the volume of gingival crevicular fluid (GCF) and in the concentrations of IL-1beta and TNF-alpha. CONCLUSIONS: Leveling and distalization of the teeth evoke increases in both the IL-1 and TNF-alpha levels that can be detected in GCF.