Enamel surface evaluation after bracket debonding and different resin removal methods.

OBJECTIVE: To assess enamel surface under scanning electron microscopy (SEM) after resin removal and enamel polishing procedures following brackets debonding, as well as compare the time required for these procedures. METHODS: A total of 180 deciduous bovine incisors were used. The enamel surface of each tooth was prepared and brackets were bonded with light cured Transbond XT composite resin. Brackets were removed in a testing machine. The samples were randomized and equally distributed into nine groups according to the resin removal and polishing technique: Group 1, 30-blade tungsten carbide bur in high speed; Group 2, 30-blade tungsten carbide bur in high speed followed by a sequence of 4 Sof-lex polishing discs (3M); Group 3, 30-blade tungsten carbide bur in high speed followed by Enhance tips (Dentsply). All groups were subdivided into (a) unpolished; (b) polished with aluminum oxide paste; and (c) polished with water slurry of fine pumice. Subsequently, the enamel surface was assessed and statistical analysis was carried out. RESULTS: There were statistically significant differences in enamel roughness and removal time among all groups. Groups 3a, 3b and 3c appeared to be the most efficient methods of removing resin with low damages to enamel. Groups 2a, 2b and 2c were the most time consuming procedures, and Group 2a caused more damages to enamel. CONCLUSION: The suggested protocol for resin removal is the 30-blade tungsten carbide bur in high speed followed by Enhance tips and polishing with aluminum oxide paste. This procedure seems to produce less damages and is less time consuming.

Enamel surface evaluation after bracket debonding and different resin removal methods

OBJECTIVE: To assess enamel surface under scanning electron microscopy (SEM) after resin removal and enamel polishing procedures following brackets debonding, as well as compare the time required for these procedures. METHODS: A total of 180 deciduous bovine incisors were used. The enamel surface of each tooth was prepared and brackets were bonded with light cured Transbond XT composite resin. Brackets were removed in a testing machine. The samples were randomized and equally distributed into nine groups according to the resin removal and polishing technique: Group 1, 30-blade tungsten carbide bur in high speed; Group 2, 30-blade tungsten carbide bur in high speed followed by a sequence of 4 Sof-lex polishing discs (3M); Group 3, 30-blade tungsten carbide bur in high speed followed by Enhance tips (Dentsply). All groups were subdivided into (a) unpolished; (b) polished with aluminum oxide paste; and (c) polished with water slurry of fine pumice. Subsequently, the enamel surface was assessed and statistical analysis was carried out. RESULTS: There were statistically significant differences in enamel roughness and removal time among all groups. Groups 3a, 3b and 3c appeared to be the most efficient methods of removing resin with low damages to enamel. Groups 2a, 2b and 2c were the most time consuming procedures, and Group 2a caused more damages to enamel. CONCLUSION: The suggested protocol for resin removal is the 30-blade tungsten carbide bur in high speed followed by Enhance tips and polishing with aluminum oxide paste. This procedure seems to produce less damages and is less time consuming. .

OBJETIVO: avaliar a superfície do esmalte, por meio de microscopia eletrônica de varredura, após descolagem de braquetes e o polimento do esmalte, com diferentes técnicas de remoção de resina, bem como comparar o tempo necessário para a realização do procedimento. MÉTODOS: foram utilizados 180 dentes bovinos decíduos. A superfície do esmalte dos dentes foi preparada e realizada a colagem dos braquetes com resina Transbond XT. Os braquetes foram removidos em máquina de ensaio mecânico. Foram formados, aleatoriamente, nove grupos, de acordo com o tipo de remoção da resina e de polimento, sendo: Grupo 1, broca de tungstênio de 30 lâminas em alta rotação; Grupo 2, broca de tungstênio de 30 lâminas em alta rotação e sequência de quatro discos Soflex (3M); Grupo 3, broca de tungstênio de 30 lâminas em alta rotação e pontas de acabamento Enhance (Dentsply). Todos os grupos foram subdividido em (a) sem polimento, (b) polimento com pasta de óxido de alumínio e (c) polimento com pedra-pomes. As superfícies foram avaliadas e foi realizada análise estatística. RESULTADOS: houve diferença estatística entre os grupos em relação à rugosidade de superfície e ao tempo de remoção. Os grupos 3a, 3b e 3c demonstraram ser os métodos mais eficientes de remoção da resina, promovendo pouco dano à superfície do esmalte. Os grupos 2a, 2b e 2c consumiram maior tempo de procedimento, e o grupo 2a causou maior dano ao esmalte. CONCLUSÃO: sugere-se como protocolo de remoção o uso de broca de tungstênio de 30 lâminas para remoção do maior volume da resina, pontas de acabamento Enhance e polimento com a pasta de óxido de alumínio, por produzirem menor dano. .

In-vivo evaluation of the surface roughness and morphology of enamel after bracket removal and polishing by different techniques.

INTRODUCTION: The aim of this study was to evaluate the surface roughness and morphology of enamel with a surface roughness tester and scanning electron microscopy after the removal of metal brackets and polishing. METHODS: Ten orthodontic patients were selected for the study. At the conclusion of orthodontic treatment, their metal brackets were removed. For each patient, teeth on one side of the mouth were randomly chosen for finishing and polishing with aluminum oxide discs (n = 10). Teeth on the other side were finished with multilaminated carbide burs (n = 10). Dental replicas (before and after tooth polishing) were obtained with epoxy resin. Three surface roughness measurements were made in different directions with an angle of 120° among them, and a mean for each dental replica was calculated. The roughness data were statistically evaluated by repeated-measurements analysis of variance. Three specimens from each group were also used for scanning electron microscopy analysis. RESULTS: After resin removal, the average roughness in the carbide bur group (0.31 µm) was significantly greater than that in the aluminum oxide disc group (0.25 µm). CONCLUSIONS: The aluminum oxide disc polishing system resulted in less enamel roughness than did the multilaminated carbide bur system.

In vitro and in vivo evaluation of the effectiveness of three dentin desensitizing treatment regimens.

PURPOSE: To evaluate the in vitro and in vivo effects of three treatment regimens on dentin permeability and reduction of dentin hypersensitivity (DH). METHODS: The desensitization treatments were: Gluma Desensitizer PowerGel (GLU), MS Coat One (MSC), and dentin burnishing with fiber-resin burs (STB). A split-chamber device was used to determine the permeability of dentin slices cut from human molars in vitro. Fluid flow through dentin was recorded with a photochemical method after EDTA cleaning, albumin soaking and desensitization treatment (n = 10). 61 study participants with three severely hypersensitive teeth each were enrolled. Sensitivity was determined with an air stimulus before, immediately after treatment, and after 1, 3 and 6 months, using a verbal rating scale. RESULTS: From the 61 study participants enrolled, 52 completed the trial. Permeability at baseline and after albumin soaking was not significantly different. All treatments produced reduced fluid flow through dentin (P > 0.05). All treatments reduced DH significantly (no or moderate sensitivity). Statistical results revealed significant differences among the treatments (P = 0.03). Mann-Whitney comparisons showed GLU, STB < MSC.

Microtensile bond strength of self-etch adhesives in different surface conditionings.

AIM: Self-etch bonding systems have been introduced recently and have the advantage of reduced operating time. Because of patient management and isolation difficulties in children, the present study aimed to evaluate microtensile bond strength of two self-etch bonding systems (AdheSE and Xeno® III) on cleaned only, ground and sandblasted enamel. MATERIALS AND METHODS: Thirty intact primary molars were selected and randomly divided into two groups according to the type of bonding used (Xeno® III and AdheSE). The teeth were divided into three subgroups according to enamel surface conditioning method: prophylaxis with pumice, grinding with coarse finishing and polishing disc, and sandblasting with aluminum oxide particles. Tetric Ceram composite then was applied. Samples were sectioned coronally and axially. The interface area of dental sticks was measured and specimens were subjected to a tensile force of 0.5 mm/min until failure. RESULTS: Microtensile bond strength of Xeno® III-sandblasting, AdheSE-sandblasting, AdheSE-grinding, and AdheSE- cleaned only were 25.5±7.7, 21.2±2.3, 12.9±2.2, and 9.1±1.1, respectively. During sectioning, all specimens of Xeno® III-cleaned only and Xeno® III-grinding groups were fractured. CONCLUSIONS: Two step AdheSE yields higher mTBS in comparison to one step Xeno ® III. In regard to surface conditioning, sandblasting increases the mTBS relative to grinding with finishing and polishing disc, and the cleaned-only enamel has the lowest mTBS.

Laboratory evaluation of extrinsic stain removal by a specially engineered sonic powered toothbrush with unique sensing and control technologies.

OBJECTIVE: The purpose of this laboratory study was to evaluate extrinsic stain removal from teeth by a specially engineered sonic powered toothbrush with unique sensing and control technologies, using the Triple Clean and the Sensitive refill brush heads, in comparison to a manual flat-trim toothbrush. METHODS: Twelve (12) artificially stained bovine teeth were tested with each product. The percentage of stain removed by each product was calculated by taking the ratio of the amount of stain removed by brushing for 800 strokes to the total amount of stain removed by subsequent application of a dental prophylaxis. The stain was quantified by measuring the light reflected by the stained teeth with a spectrophotometer. Data were reported as L*, lightness of the stain, and as W*, a whiteness index comprising the lightness, hue, and chroma of reflected light. Statistical analyses were performed separately for the AL* and AW* scores. Comparisons of the toothbrushes with respect to baseline-adjusted deltaL* and deltaW* scores were performed using an analysis of covariance (ANCOVA). Post-ANCOVA pair-wise comparisons of the study toothbrushes were performed using Tukey's test for multiple comparisons. All statistical tests of hypotheses were two-sided, and employed a minimum level of significance of 0.05. RESULTS: The percentage of stain removed by the sonic powered toothbrush, using either the Triple Clean brush head or the Sensitive brush head under laboratory test conditions, is superior (p < 0.05) to the percentage of stain removed by the manual flat-trim toothbrush when analyzed for both the deltaL* and deltaW* scores. The mean percentage of stain removed was 62.10 for the power toothbrush with the Triple Clean brush head, 49.01 for the power toothbrush with the Sensitive brush head, and 30.56 for the manual flat-trim toothbrush when calculated using deltaL* scores. The mean percentage of stain removed was 59.89 for the power toothbrush with the Triple Clean brush head, 46.83 for the power toothbrush with the Sensitive brush head, and 29.25 for the manual flat-trim toothbrush when calculated using deltaW* scores. CONCLUSIONS: This new specially engineered sonic powered toothbrush with unique sensing and control technologies effectively removes extrinsic stains from the surface of teeth under laboratory test conditions with both the Triple Clean and the Sensitive brush heads. The effectiveness of stain removal with either brush head is significantly greater than the effectiveness of stain removal of a manual flat-trim toothbrush under these conditions.

Does professional preventive care benefit from additional subgingival irrigation?

The effect of an oral irrigator (Water Pik, Intersante) with a subgingival tip (Pik Pocket Subgingival Tip, Intersante) in the reduction of gingivitis was investigated in a single-blind three-group study involving 45 volunteers (age 46.2+/-10.2). All volunteers (inclusion criteria: gingivitis or a superficial periodontitis) were examined and underwent professional tooth cleaning at the first appointment. They were then randomly distributed in three groups: one group used the irrigator with the subgingival tip once daily with just tap water, in addition to their regular oral hygiene; another group also used an herbal-based mouth rinse (Parodontax, GlaxoSmithkline) in the water of the irrigator; a third group did not use an irrigator or any irrigant and therefore served as control. All groups received professional oral care education at each appointment. The investigation period was 3 months. At baseline and after 4, 8, and 12 weeks, the plaque index (PI, scores 0-5), gingival index (GI, scores 0-3), bleeding index (BI scores 0-5), and sulcus fluid flow rate (SFFR, Periotron 6000) at the Ramfjord teeth were scored. At baseline and after 3 months, the probing depth (millimeters) was measured at six surfaces of all teeth. A significant reduction in BI, PI, GI, probing depth, and SFFR was observed within 3 months. With all volunteers, however, there was no statistically significant difference ( p>/=0.05, Wilcoxon-test, SAS 6.04) between the three groups at any time. The additional use of the Water Pik irrigator with the Pik Pocket subgingival irrigation device with or without an herbal mouth rinse showed no clinical benefit over professional education in oral hygiene alone.

The effect of different debonding techniques on the enamel surface: an in vitro qualitative study.

The purpose of this in vitro study was to evaluate the enamel surface structure subjected to various techniques of debonding orthodontic attachments and to develop a technique for residual adhesive removal that restores the enamel surface as closely as possible to its pretreatment condition without introducing iatrogenic damage. Enamel surface structure was examined with a scanning electron microscope before bonding of twin metal brackets to 60 previously extracted premolars with two heavily filled composite resins. Two groups, each consisting of 30 teeth, were equally subdivided into 10 subgroups. The first three subgroups were used to compare the efficacy of three bracket removing instruments. Since there were no differences in the debonding properties between the two resins, the two groups were combined. In this way, each subgroup (n = 6) could be used for a more meaningful comparison. On the basis of the results of this comparison, the bracket removing instrument that produced the most consistent separation at the bracket-adhesive interface was used in the remainder of the study. After appliance removal, the teeth were again examined microscopically and photographed, and seven different procedures for residual resin removal were compared. After resin removal, the final polished enamel surface was followed by microscopic evaluation. Results of this study show the bracket removing plier produced the most consistent separation at the bracket-adhesive interface, leaving the enamel surface intact. Carbide burs at high speed and air coolant proved to be efficient in residual resin removal, but when used alone, failed to produce a satisfactory enamel surface. After the removal of residual resin, graded medium, fine, and superfine Sof-Lex finishing disks (Unitek Corp., Monrovia, Calif.) produced surfaces that could be readily restored satisfactorily after receiving a final polish with a rubber cup and Zircate paste.

In vitro analysis of the effects of two air-abrasive prophylaxis systems and inlet air pressure on the surface of titanium abutment cylinders.

PURPOSE: The purpose of this study was to investigate the effects of two air-abrasive prophylaxis systems and the effect of inlet air pressure on the surface of Brånemark titanium abutment cylinders. MATERIALS AND METHODS: Single abutment cylinders were treated with either the Prophy-Jet system (sodium bicarbonate abrasive) (Dentsply International, York, PA) or the Microprophy system (aluminum oxide abrasive) (Danville Engineering Co, Danville, CA) for 60 seconds at an inlet air pressure of 60 psi or 90 psi. The effects on the surface of each abutment cylinder were visually inspected by scanning electron microscopy. RESULTS: A comparison of abutment cylinder surfaces after treatment showed that the Prophy-Jet system removed machining marks to a greater degree than the Microprophy system. Sodium bicarbonate particles from the Prophy-Jet system were significantly larger than the aluminum oxide particles used with the Microprophy system, potentially accounting for the difference in abrasivity. In addition, inlet air pressure of 60 psi caused removal of machining marks to a greater degree than an inlet air pressure of 90 psi. The principle of phase separation may account for the lower inlet air pressure causing more removal of machining marks than the higher inlet air pressure. CONCLUSIONS: Under the experimental conditions tested, neither of the two systems tested seemed to cause significant abrasion of the surface of titanium abutment cylinders.

Effectiveness of antimicrobial mouthrinses on aerosols produced by an air polisher.

PURPOSE: The purpose of this examiner-blind investigation was to study the effect of two antimicrobial mouthrinses on the quantity and potential respiratory-penetrating ability of microorganisms generated by an air-abrasive polisher. METHODS: Forty-five adult subjects were randomly assigned to one of three groups and asked to rinse for 30 seconds with 15 ml of either a 0.12% chlorhexidine rinse, an essential oil mouthrinse, or water prior to air polishing. Prior to treatment, microbes in ambient air were collected for five minutes using an Andersen air sampler. This device simulates the human respiratory system and collects airborne microbes by means of blood agar plates stacked in a cascade impact system. Bacteria found at stages two, four, and six--representing the pharynx, bronchi, and alveoli-were collected and counted in this study. During three minutes of air-abrasive instrumentation and two minutes immediately following, airborne microbes were again collected. Agar plates removed from the sampler were incubated for 24 hours at 37 degrees C. Colony-forming units per cubic foot of air (CFUs/ft(3)) were enumerated using a Lab Line colony counter. Data were analyzed using a two-factor repeated measure ANOVA and Dunn's multiple mean comparison techniques. RESULTS: Results showed no significant effect of prerinsing among treatment groups. An increase in CFUs/ft(3) was found at each sequential stage of the air sampler, resulting in a statistically significant within-group effect (p< or =.05). Additionally, a significant interaction was found between prerinse treatment and respiratory stage (p< or =.05) . CONCLUSION: While the air-abrasive polisher produced significant amounts of deeply penetrating bacterial aerosol, differences in CFUs/ft(3) generated following the antimicrobial prerinsing tested are of little clinical significance.

The effect of oral irrigation with a magnetic water treatment device on plaque and calculus.

Calculus formation on tooth surfaces is analogous to the formation of lime and scale deposits in plumbing. Magnetic water devices have been shown to significantly reduce scale deposits in industry; therefore an oral irrigator with a magnetic water device may have a similar effect on calculus. To test this hypothesis, a double-blind clinical study was established using 64 irrigators, 30 of which had their magnetic devices removed. 54 patients with heavy supragingival calculus were given irrigators at random after prophylaxis. Instructions were given to irrigate twice a day, particularly the lower 6 anterior teeth. The patients were also told not to floss these 6 teeth which were to be the study teeth. They were examined after 3 months and measurements were taken of the accretions adhering to the study teeth. No attempt was made to determine whether the adhering material was hard or soft so it must be assumed that at least some of the measured material was also plaque. The measurements of the group using an irrigator with a magnetic device showed a 44% greater reduction in calculus volume (p < 0.0005) and a 42% greater reduction in area (p < 0.0001) over the group using an unmagnetized irrigator. There appears to be a statistically significant difference in supragingival accretion volumes between conventional irrigation and using an irrigator with a magnetic water treatment device.

Self-adjusting abrasiveness: a new technology for prophylaxis pastes.

An ideal prophylaxis paste should have both cleaning and polishing properties. Key elements would be abrasive particles that become less aggressive under load. The abrasive perlite, a volcanic glass with a sheetlike geometry, is claimed to have these unique properties. This study evaluated the average particle size, size distribution, and morphology of perlite in raw form, in an unused prophylaxis paste, and a used prophylaxis paste. The surface roughness induced on enamel and dentinal specimens was quantitated after paste application in either a rubber cup or a nylon brush. Flour of pumice, a standard prophylaxis paste, a polishing paste, and water were tested similarly. The luster induced by the tested pastes and controls was assessed. Perlite blunted and disintegrated under load. The perlite-containing prophylaxis paste acted as a fine or superfine prophylaxis paste, although it was ranked as medium, based on the mean particle size of its abrasive in the fresh, unused form. Perlite might provide the properties required for the abrasive material of an ideal prophylaxis paste.

The effects of two air-powder abrasive prophylaxis systems on the surface of machined titanium: a pilot study.

This in vitro pilot project compared the effect of two air-abrasive prophylaxis systems on the surface of machined titanium. Single Brånemark titanium abutment cylinders were exposed to the Prophy-Jet and Microprophy systems for 90 seconds each. Both of the test cylinders were compared with an untreated control cylinder by scanning electron microscopy. Machining marks were completely removed by the Prophy-Jet and only partially removed by the Microprophy. Both of the resultant surfaces appeared to be smoother and thus may be more resistant to plaque formation. A rationale for the removal of machining marks is presented, although the reason for the difference in removal by the two systems is unclear. The prophylaxis cleaning powders were also examined by scanning electron microscopy and exhibited similar particle dimensions and morphology. A noncrystalline deposit was observed on the surface of the abutment cylinder exposed to the Microprophy. Energy dispersive spectroscopy analysis revealed that the deposit consisted almost entirely of sodium. Further investigation of the deposit is needed.

An electron microscopic evaluation of the enamel surface subsequent to various debonding procedures.

In this study, enamel surface roughness was investigated following the use of various combinations of bonding agents, burrs and polishing procedures. Orthodontic brackets were bonded to 135 premolar teeth extracted from adolescents. Subsequent to debonding and finishing, the enamel surface was gold coated and examined in the scanning electron microscope. Each 200x photomicrograph was graded according to surface roughness and assigned to one of four selected standard grades. The use of different composites and different burs showed no significant effect on the finish of the enamel surface using Chi-square tests. Only two finishing procedures had a significant effect on surface roughness. The use of a Soflex disc followed by pumice slurry resulted in the roughest enamel surface and the use of pumice alone produced the smoothest enamel surface.