Efeito do polimento superficial a seco ou úmido sobre o brilho, rugosidade e desgaste de resina composta nanoparticulada antes e após envelhecimento artificial / Effect of dry or wet surface polishing on the gloss, roughness and wear of nanoparticulate composite resin before and after artificial aging

Este trabalho teve como objetivo investigar a rugosidade, o desgaste e o brilho superficial de uma resina composta nanoparticulada (Filtek Z350 XT - 3M ESPE), com diferentes sistemas de polimento a seco e lubrificado antes e após envelhecimento artificial. Foram confeccionados 100 espécimes de resina composta em forma de disco, divididos em: grupo controle (sem polimento) e em três sistemas de polimento (pontas de diamante de etapa única Dimanto - VOCO, discos de lixa Sof-Lex Pop-On - 3M ESPE - e escova de polimento com carbeto de silício nas cerdas Astrobrush - IVOCLAR VIVADENT). Os sistemas polidores foram empregados sem lubrificação, com água e com vaselina. Após a fase de envelhecimento por escovação, foi realizado o repolimento das amostras, exceto no grupo controle. Ao final de cada tempo do estudo (inicial, polimento, envelhecimento e repolimento), os grupos foram submetidos as leituras de rugosidade, desgaste e brilho, verificando assim a efetividade de cada sistema de polimento. Os dados referentes a cada avaliação quantitativa foram submetidos à análise estatística de variância de medidas repetidas. As comparações múltiplas foram realizadas por teste Pos-hoc de Tukey. Diferenças significantes foram determinadas por p < 0,05. Para as análises de brilho e rugosidade póspolimento o Dimanto não foi influenciado pelo uso ou não de lubrificantes. O Sof-Lex Pop-On obteve melhor desempenho sem utilização de lubrificante, enquanto a escova Astrobrush apresentou maiores valores de brilho e menor rugosidade quando lubrificada por água ou vaselina. Em relação ao desgaste superficial, o Dimanto foi melhor, quando associado a vaselina. O Sof-Lex PopOn apresentou menor desgaste, quando utilizado com água. A escova Astrobrush obteve o pior resultado quando lubrificada com vaselina. Portanto, o brilho, a rugosidade e o desgaste superficial dependem do polidor e da combinação com ou sem lubrificação(AU)

The aim of this study was to investigate the roughness, wear and surface gloss of a nanoparticulated resin composite (Filtek Z350 XT - 3M ESPE), with dry and lubricated polishing systems before and after artificial aging. One hundred resin composite specimens were fabricated in cylindrical shape, which was further divided into: control group (no polishing) and three polishing systems (One step diamond tips Dimanto -VOCO, Sof-Lex Pop-On -3M ESPE, and a silicon carbide polishing brush - Astrobrush -IVOCLAR VIVADENT). Polishing systems was used dry, with water or petroleum jelly. After aging by simulated tooth brushing, the samples' repolishing was carried out, except in the control group. After each study period (initial, polishing, aging and repolishing), the groups were subjected to roughness, wear and gloss, thus verifying the effectiveness of each polishing system. The data for each quantitative evaluation was submitted to repeated-measures analysis of variance. Multiple comparisons were performed by Tukey post-hoc test. Significant differences were determined by p <0.05. For post-polishing gloss and roughness analyzes, Dimanto was not influenced by the use or not of lubricants. Sof-Lex Pop-On achieved better performance without using lubricant, while the Astrobrush brush showed higher values of gloss and less roughness when lubricated by water or petroleum jelly. Regarding surface wear, Dimanto was better when associated with petroleum jelly. Sof-Lex Pop-On showed less wear when used with water. The Astrobrush brush obtained the worst result when lubricated with petroleum jelly. The brightness, roughness and surface wear depend on the polisher and the combination with or without lubrication(AU).

Enamel protection after stripping procedures: An in vivo study.

INTRODUCTION: Interproximal enamel reduction (IPR) is a clinical procedure that has been in use since the advent of non-extraction orthodontic techniques. However, such a procedure affects the surface condition of the enamel and may predispose patients to cavities and hypersensitivity. The use of a remineralizing agent is recommended to prevent these side effects. The objective of our study was to evaluate the evolution of stripped proximal dental surfaces after exposure to the oral environment for 4 months with and without fluoride protection. MATERIALS AND METHODS: Our sample consisted of 14 premolars (PM) from 6 patients of the Dentofacial Orthopaedics Department of the Consultation and Dental Treatment Centre of Rabat (CDTC) who required orthodontic treatment with PM extraction and had given their informed consent. The teeth were divided into 5 groups: group 1: intact enamel; group 2: intact enamel+fluoride varnish+4-month oral exposure; group 3: IPR (manual and mechanized)+extraction; group 4: IPR (manual and mechanized) without varnish+4-month oral exposure; group 5: IPR (manual and mechanized)+fluoride varnish+4-month oral exposure. Proximal surfaces were subjected to qualitative analysis by scanning electron microscopy and quantitative analysis by Dispersive Energy Spectroscopy (DES) to quantify the percentage of mineral elements. RESULTS: Exposure of stripped dental surfaces to the oral environment for 4 months with or without fluoride protection showed the persistence of surface irregularities caused by stripping. We noted an improvement in the percentage of mineral elements for both groups with and without fluoride protection. However, the percentages of calcium (Ca) and phosphorus (P) were close to that of intact enamel in the fluoride varnish group. CONCLUSION: Protecting stripped surfaces with fluoride varnish could help preserve the integrity of the enamel surface by restoring some of the mineral elements lost during stripping.

In vivo enamel stripping: A macroscopic and microscopic analytical study.

INTRODUCTION: Interdental stripping is often used in orthodontics to correct discrepancies of tooth shape or size. However, this procedure involves significant risks for the enamel. The roughness of the enamel surface might depend on the instruments used; it can lead to the accumulation of cariogenic plaque and periodontal problems. The main objective of our study was to evaluate the enamel surface condition after interproximal stripping in the mouth, by comparing different manual and mechanized enamel reduction protocols; on the other hand, the topography of the stripped area was observed to specify its location on the stripped proximal surfaces. MATERIALS AND METHODS: An in vivo study was carried out: interdental stripping was performed in the mouths of patients undergoing orthodontic treatment and on healthy teeth intended for extraction for orthodontic or periodontal reasons. The sample was divided into four groups: in group 1, the distal faces were stripped with conventional single-sided diamond abrasive strips and non-stripped mesial faces (control faces); in group 2: the distal faces were stripped with the manual ContacEZ IRP Kit (single-sided abrasive files of different grain sizes) and non-stripped mesial faces (control faces); in group 3: the faces were stripped with ContacEZ IRP diamond discs attached to a handpiece and the mesial faces were not stripped (control faces); in group 4: the distal faces were stripped with the Intensiv Ortho-Strips mechanized system and the mesial faces were not stripped (control faces). RESULTS: Our study showed that regardless of the type of stripping material used, the enamel surface showed some roughness with the presence of striations and grooves of different widths and depths. Our observations objectivised more regular and less roughened enamel surface conditions when using the Intensiv oscillating files. Manual instruments (abrasive strips and files) have shown rougher and more irregular surface conditions that may constitute a real risk of carious and periodontal disease. The macroscopic evaluation of the topography of the stripped area showed that there is great variability in the situation and extent of the stripped area in relation to several parameters. CONCLUSION: The current mechanized instruments (oscillating files) provide enamel stripping with more comfort for the patient and the practitioner, and seem to produce a more regular and less harmful surface condition for the tooth and periodontium.

The Effect of a Continuous Mechanical Polishing Protocol on Surface Roughness, Biofilm Adhesion, and Color Stability of Acrylic Resin Artificial Teeth.

PURPOSE: Acrylic resin properties are susceptible to change over the duration of use, thereby decreasing prosthesis longevity. To make the material less susceptible to the action of external agents such as stain-causing liquids and cleaning solutions, polishing procedures are recommended. A specific mechanical polishing procedure performed regularly was evaluated regarding the biofilm adhesion, surface roughness (Ra), color stability (ΔE), and mass changes in acrylic resin artificial teeth. MATERIALS AND METHODS: Sixty artificial teeth divided into two groups (n = 30) were immersed in distilled water (WT) and coffee (CF). These groups were then subdivided (n = 10) according to the type of polishing procedure administered: no polishing, biweekly polishing (once every 2 weeks) (pol 1), or monthly polishing (once a month) (pol 2), using aluminum oxide paste and a felt polishing wheel attached to an electric motor at a speed of 3000 rpm. Properties were evaluated at baseline and after 4, 8, 12, and 24 months of simulated immersion. At the end, the adhesion of Candida albicans and Streptococcus mutans multispecies biofilm in all groups was assessed. RESULTS: The CF group showed an increased Ra and weight, and a significantly greater ΔE compared to the WT group. The polishing procedure reduced Ra and minimized the stains caused by coffee, without losing mass, with the biweekly regime more effective than the monthly regime. Also, polishing reduced the adhesion of biofilm in the CF groups, again with the biweekly regime the most effective. CONCLUSIONS: When performed regularly, the mechanical polishing procedure tested reduces the changes in artificial teeth subjected to immersion in coffee, with the biweekly frequency most effective regarding the properties evaluated.

Routine scale and polish for periodontal health in adults.

BACKGROUND: Many dentists or hygienists provide scaling and polishing for patients at regular intervals, even for those at low risk of developing periodontal disease. There is debate over the clinical and cost effectiveness of 'routine scaling and polishing' and the optimal frequency at which it should be provided for healthy adults.A 'routine scale and polish' treatment is defined as scaling or polishing, or both, of the crown and root surfaces of teeth to remove local irritational factors (plaque, calculus, debris and staining), which does not involve periodontal surgery or any form of adjunctive periodontal therapy such as the use of chemotherapeutic agents or root planing. Routine scale and polish treatments are typically provided in general dental practice settings. The technique may also be referred to as prophylaxis, professional mechanical plaque removal or periodontal instrumentation.This review updates a version published in 2013. OBJECTIVES: 1. To determine the beneficial and harmful effects of routine scaling and polishing for periodontal health.2. To determine the beneficial and harmful effects of routine scaling and polishing at different recall intervals for periodontal health.3. To determine the beneficial and harmful effects of routine scaling and polishing for periodontal health when the treatment is provided by dentists compared with dental care professionals (dental therapists or dental hygienists). SEARCH METHODS: Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 10 January 2018), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2017, Issue 12), MEDLINE Ovid (1946 to 10 January 2018), and Embase Ovid (1980 to 10 January 2018). The US National Institutes of Health Trials Registry (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases. SELECTION CRITERIA: Randomised controlled trials of routine scale and polish treatments, with or without oral hygiene instruction, in healthy dentate adults without severe periodontitis. We excluded split-mouth trials. DATA COLLECTION AND ANALYSIS: Two review authors screened the results of the searches against inclusion criteria, extracted data and assessed risk of bias independently and in duplicate. We calculated mean differences (MDs) (or standardised mean differences (SMDs) when different scales were reported) and 95% confidence intervals (CIs) for continuous data. We calculated risk ratios (RR) and 95% CIs for dichotomous data. We used a fixed-effect model for meta-analyses. We contacted study authors when necessary to obtain missing information. We rated the certainty of the evidence using the GRADE approach. MAIN RESULTS: We included two studies with 1711 participants in the analyses. Both studies were conducted in UK general dental practices and involved adults without severe periodontitis who were regular attenders at dental appointments. One study measured outcomes at 24 months and the other at 36 months. Neither study measured adverse effects, changes in attachment level, tooth loss or halitosis.Comparison 1: routine scaling and polishing versus no scheduled scaling and polishingTwo studies compared planned, regular interval (six- and 12-monthly) scale and polish treatments versus no scheduled treatment. We found little or no difference between groups over a two- to three-year period for gingivitis, probing depths, oral health-related quality of life (all high-certainty evidence) and plaque (low-certainty evidence). The SMD for gingivitis when comparing six-monthly scale and polish treatment versus no scheduled treatment was -0.01 (95% CI -0.13 to 0.11; two trials, 1087 participants), and for 12-monthly scale and polish versus no scheduled treatment was -0.04 (95% CI -0.16 to 0.08; two trials, 1091 participants).Regular planned scale and polish treatments produced a small reduction in calculus levels over two to three years when compared with no scheduled scale and polish treatments (high-certainty evidence). The SMD for six-monthly scale and polish versus no scheduled treatment was -0.32 (95% CI -0.44 to -0.20; two trials, 1088 participants) and for 12-monthly scale and polish versus no scheduled treatment was -0.19 (95% CI -0.31 to -0.07; two trials, 1088 participants). The clinical importance of these small reductions is unclear.Participants' self-reported levels of oral cleanliness were higher when receiving six- and 12-monthly scale and polish treatments compared to no scheduled treatment, but the certainty of the evidence is low.Comparison 2: routine scaling and polishing at different recall intervalsTwo studies compared routine six-monthly scale and polish treatments versus 12-monthly treatments. We found little or no difference between groups over two to three years for the outcomes of gingivitis, probing depths, oral health-related quality of life (all high-certainty evidence) and plaque (low-certainty evidence). The SMD for gingivitis was 0.03 (95% CI -0.09 to 0.15; two trials, 1090 participants; I2 = 0%). Six- monthly scale and polish treatments produced a small reduction in calculus levels over a two- to three-year period when compared with 12-monthly treatments (SMD -0.13 (95% CI -0.25 to -0.01; 2 trials, 1086 participants; high-certainty evidence). The clinical importance of this small reduction is unclear.The comparative effects of six- and 12-monthly scale and polish treatments on patients' self-reported levels of oral cleanliness were uncertain (very low-certainty evidence).Comparison 3: routine scaling and polishing provided by dentists compared with dental care professionals (dental therapists or hygienists)No studies evaluated this comparison.The review findings in relation to costs were uncertain (very low-certainty evidence). AUTHORS' CONCLUSIONS: For adults without severe periodontitis who regularly access routine dental care, routine scale and polish treatment makes little or no difference to gingivitis, probing depths and oral health-related quality of life over two to three years follow-up when compared with no scheduled scale and polish treatments (high-certainty evidence). There may also be little or no difference in plaque levels over two years (low-certainty evidence). Routine scaling and polishing reduces calculus levels compared with no routine scaling and polishing, with six-monthly treatments reducing calculus more than 12-monthly treatments over two to three years follow-up (high-certainty evidence), although the clinical importance of these small reductions is uncertain. Available evidence on the costs of the treatments is uncertain. The studies did not assess adverse effects.

Tooth color change due to different etching and debonding procedures.

OBJECTIVES:: To compare the effects of different etching techniques, 12-, 24-bladed tungsten carbide burs, and polishing discs on tooth color changes during orthodontic treatment. MATERIALS AND METHODS:: 59 individuals (mean age: 15.20 ± 1.59 years) were divided into four groups: 37% phosphoric acid and adhesive primer was used in Groups I and II whereas self-etch primer was used in Groups III and IV for enamel preparation. After orthodontic treatment, residual adhesives were cleaned with 12-bladed tungsten carbide burs in Groups I and III, while 24-bladed tungsten carbide burs were used in Groups II and IV. All teeth were polished with medium and fine Sof-Lex XT discs (3M ESPE, St Paul, Minnesota). Color measurements were taken from upper incisors and canines at pretreatment (T0), after cleaning with tungsten carbide burs (T1) and polishing with discs (T2). Wilcoxon test was used for evaluation of L*, a*, b* changes and Kruskal-Wallis for intergroup comparison of color changes. RESULTS:: L*, a*, b* values, except a* at Groups I, II, IV, and b* at Group III, changed significantly ( P < .05). Groups III and IV showed significantly different color alterations from T0 to T1 ( P < .05). After polishing, tooth color alterations were not significantly different among the groups. CONCLUSIONS:: In self-etch bonding groups, a 12-bladed tungsten carbide bur caused less color change than the 24-bladed tungsten carbide bur. Orthodontic treatment resulted with visible and clinically unacceptable tooth color alterations regardless of the enamel preparation and clean-up techniques. Polishing reduced the effect of tungsten carbide burs, but did not affect the total influence of orthodontic treatment on the tooth color.

Monolithic Ceramics: Effect of Finishing Techniques on Surface Properties, Bacterial Adhesion and Cell Viability.

INTRODUCTION: This study evaluated the morphology, biofilm formation, and viability of human gingival fibroblasts in contact with two monolithic ceramics after two different finishing techniques: polishing or glazing. For this, 92 blocks (4.5 × 4.5 × 1.5 mm) of each ceramic were made using high translucency zirconia partially stabilized by yttrium (YZHT) and lithium silicate reinforced by zirconium (ZLS). METHODS AND MATERIALS: Blocks were sintered and then divided into glazing (g) or polishing (p) surface finish. Surface roughness (Ra and RSm) was evaluated through a contact rugosimeter and profilometry. Specimens were contaminated for heterotypic biofilm formation with Streptococcus mutans, Streptococcus sanguinis and Candida albicans for 16 hours. Biofilm was quantified by counting the colony forming units (CFU/mL) and analyzed by scanning electron microscopy (SEM). Fibroblast viability was evaluated by MTT assay. Surface free energy (SFE) was also determined. Roughness data were evaluated using nonparametric tests, while SFE, MTT and CFU results were evaluated by analysis of variance and Tukey test, and MTT data were also submitted to t-test (all, α=0.05). RESULTS: Results showed that polished samples presented a lower high profile mean ( p<0.001); however, YZHTg presented less space between defects ( p=0.0002). SFE showed that YZHT presented higher SFE than ZLS. Profilometry evidenced more homogeneity on polished surfaces. The interaction of finishing technique and microorganisms influenced the CFU ( p=0.00). MTT assay demonstrated initial severe cytotoxic behavior for polished surfaces. SEM images showed homogeneous surfaces, except for glazed YZHT. CONCLUSION: Glazed surfaces have a greater roughness and tend to accumulate more biofilm. Polished surfaces have higher SFE; however, they are temporarily cytotoxic.

An in-situ pilot study to investigate the native clinical resistance of enamel to erosion.

OBJECTIVES: To investigate the differences in susceptibility of the surface of native and polished enamel to dietary erosion using an in-situ model. METHODS: Thirty healthy volunteers (n = 10 per group) wore mandibular appliances containing 2 native and 2 polished enamel samples for 30 min after which, the samples were exposed to either an ex-vivo or in-vivo immersion in orange juice for 5, 10 or 15 min and the cycle repeated twice with an hour's interval between them. Samples were scanned with a non-contacting laser profilometer and surface roughness was extracted from the data, together with step height and microhardness change on the polished enamel samples. RESULTS: All volunteers completed the study. For native enamel there were no statistical difference between baseline roughness values versus post erosion. Polished enamel significantly increased mean (SD) Sa roughness from baseline for each group resulting in roughness change of 0.04 (0.03), 0.06 (0.04), 0.04 (0.03), 0.06 (0.03), 0.08 (0.05) and 0.09 (0.05) µm respectively. With statistical differences between roughness change 45 min in-vivo versus 45 min ex-vivo (p < 0.05). Microhardness significantly decreased for each polished group, with statistical differences in hardness change between 30 min in-vivo versus 30 min ex-vivo (p < 0.05), 45 min in-vivo versus 30 min ex-vivo (p < 0.01), 45 min in-vivo versus 45 min ex-vivo (p < 0.01). CONCLUSIONS: The native resistance to erosion provided clinically is a combination of the ultrastructure of outer enamel, protection from the salivary pellicle and the overall effects of the oral environment. CLINICALTRIALS. GOV IDENTIFIER: NCT03178968. CLINICAL SIGNIFICANCE: This study demonstrates that outer enamel is innately more resistant to erosion which is clinically relevant as once there has been structural breakdown at this level the effects of erosive wear will be accelerated.

Comparison of two different techniques used for the maintenance of peri-implant soft tissue health: a pilot randomized clinical trial.

OBJECTIVES: The aim of this pilot study was to compare the effectiveness of two different methods of debridement on maintaining and improving peri-implant soft tissue health over a period of 12 months. MATERIALS AND METHODS: Twenty adult patients (25 implants) were enrolled in a randomized, single-blinded, parallel group clinical trial. All implants included showed no signs of pathologic bone loss. Patients were scheduled to be reviewed every 3 months over a 12 months period. Nine patients (15 implants) were randomly allocated to a test group and treated with a low abrasive air polishing powder (Air-Flow® Perio, EMS) (AFP) and another nine (10 implants) to a control group and treated with titanium curettes (TC). Peri-implant crevicular fluid samples were analyzed to quantitatively measure the concentration of six interleukins (IL-6, IL-8, IL-1ß, TNF, IL-10 and IL-12). A multilevel analysis was used to test the comparison between the two treatments. The same analysis was used to study the relationship between clinical parameters and cytokines while controlling for confounding factors. RESULTS: There was no significant difference in bleeding on probing (BOP) between the two treatment methods (p = .35). Both debridement techniques resulted in a similar reduction of BOP (40.04% and 39.93%). IL-6 was the only cytokine of the six investigated that demonstrated a correlation with a clinical parameter (BOP) (p = .05). CONCLUSIONS: Both treatment methods were proven to be effective in reducing peri-implant inflammation and preventing further disease progression. Some cytokines may act as markers for peri-implant disease as the present study showed a significant relationship between IL-6 and BOP.

Effects of various debonding and adhesive clearance methods on enamel surface: an in vitro study.

BACKGROUND: The purpose of this study was to evaluate orthodontic debonding methods by comparing the surface roughness and enamel morphology of teeth after applying two different debonding methods and three different polishing techniques. METHODS: Forty eight human maxillary premolars, extracted for orthodontic reasons, were randomly divided into three groups. Brackets were bonded to teeth with RMGIC (Fuji Ortho LC, GC, Tokyo, Japan) (two groups, n = 18 each) after acid etching (30s), light cured for 40 s, exposed to thermocycling, then underwent 2 different bracket debonding methods: debonding pliers (Shinye, Hangzhou, China) or enamel chisel (Jinzhong, Shanghai, China); the third group (n = 12) comprised of untreated controls, with normal enamel surface roughness. In each debonded group, three cleanup techniques (n = 6 each) were tested, including (I) diamond bur (TC11EF, MANI, Tochigi, Japan) and One-Gloss (Midi, Shofu, Kyoto, Japan), (II) a Super-Snap disk (Shofu, Kyoto, Japan), and (III) One-Gloss polisher. The debonding methods were compared using the modified adhesive remnant index (ARI, 1-5). Cleanup efficiencies were assessed by recording operating times. Enamel surfaces were qualitatively and quantitatively evaluated with scanning electron microscopy (SEM) and surface roughness tester, respectively. Two surface roughness variables were evaluated: Ra (average roughness) and Rz (10-point height of irregularities). RESULTS: The ARI scores of debonded teeth were similar with debonding pliers and enamel chisel (Chi-square = 2.19, P > 0.05). There were significant differences between mean operating time in each group (F = 52.615, P < 0.01). The diamond bur + One-Gloss took the shortest operating time (37.92 ± 3.82 s), followed by the Super-Snap disk (56.67 ± 7.52 s), and the One-Gloss polisher (63.50 ± 6.99 s). SEM appearance provided by the One-Gloss polisher was the closest to the intact enamel surface, and surface roughness (Ra: 0.082 ± 0.046 µm; Rz: 0.499 ± 0.200 µm) was closest to the original enamel (Ra: 0.073 ± 0.048 µm; Rz: 0.438 ± 0.213 µm); the next best was the Super-Snap disk (Ra: 0.141 ± 0.073 µm; Rz: 1.156 ± 0.755 µm); then, the diamond bur + One-Gloss (Ra: 0.443 ± 0.172 µm; Rz: 2.202 ± 0.791 µm). CONCLUSIONS: Debonding pliers were safer than enamel chisels for removing brackets. Cleanup with One-Gloss polisher provided enamel surfaces closest to the intact enamel, but took more time, and Super-Snap disks provided acceptable enamel surfaces and efficiencies. The diamond bur was not suitable for removing adhesive remnant.

Consensus Conference Findings on Supragingival and Subgingival Air Polishing.

A consensus conference was convened to evaluate and address issues of safety and efficacy when using glycine powder in an air-powder jet device for supra- and subgingival applications during dental prophylaxis and periodontal maintenance. The conference reported the following conclusions: 1) Supra- and subgingival air polishing using glycine powder is safe and effective for removal of biofilms from natural tooth structure and restorative materials; 2) there is no evidence of soft-tissue abrasion when using glycine powder in an air-polishing device; 3) in periodontal probing depths of 1 mm to 4 mm, glycine-powder air polishing, using a standard air-polishing nozzle, is more effective at removing subgingival biofilm than manual or ultrasonic instruments; and 4) at probing depths of 5 mm to 9 mm, using a subgingival nozzle, glycine powder air polishing is more effective at removing subgingival biofilm than manual or ultrasonic instrumentation. This conference statement, supported by an industry grant, was drafted by a panel of distinguished dental professionals.

Effect of artificial toothbrushing and water storage on the surface roughness and micromechanical properties of tooth-colored CAD-CAM materials.

STATEMENT OF PROBLEM: Because of the different composition of resin-ceramic computer-aided design and computer-aided manufacturing (CAD-CAM) materials, their polishability and their micromechanical properties vary. Moreover, depending on the composition of the materials, their surface roughness and micromechanical properties are likely to change with time. PURPOSE: The purpose of this in vitro study was to investigate the effect of artificial toothbrushing and water storage on the surface roughness (Ra and Rz) and the micromechanical properties, surface hardness (Vickers [VHN]) and indentation modulus (EIT), of 5 different tooth-colored CAD-CAM materials when polished with 2 different polishing systems. MATERIAL AND METHODS: Specimens (n=40 per material) were cut from a composite resin (Paradigm MZ100; 3M ESPE), a feldspathic ceramic (Vitablocs Mark II; Vita Zahnfabrik), a resin nanoceramic (Lava Ultimate; 3M ESPE), a hybrid dental ceramic (Vita Enamic; Vita Zahnfabrik), and a nanocomposite resin (Ambarino High-Class; Creamed). All specimens were roughened in a standardized manner and polished either with Sof-Lex XT discs or the Vita Polishing Set Clinical. Surface roughness, VHN, and EIT were measured after polishing and after storage for 6 months (tap water, 37°C) with periodic, artificial toothbrushing. The surface roughness, VHN, and EIT results were analyzed with a nonparametric ANOVA followed by Kruskal-Wallis and exact Wilcoxon rank sum tests (α=.05). RESULTS: Irrespective of polishing system and of artificial toothbrushing and storage, Lava Ultimate generally showed the lowest surface roughness and Vitablocs Mark II the highest. As regards micromechanical properties, the following ranking of the CAD-CAM materials was found (from highest VHN/EIT to lowest VHN/EIT): Vitablocs Mark II > Vita Enamic > Paradigm MZ100 > Lava Ultimate > Ambarino High-Class. Irrespective of material and of artificial toothbrushing and storage, polishing with Sof-Lex XT discs resulted in lower surface roughness than the Vita Polishing Set Clinical (P≤.016). However, the polishing system generally had no influence on the micromechanical properties (P>.05). The effect of artificial toothbrushing and storage on surface roughness depended on the material and the polishing system: Ambarino High-Class was most sensitive to storage, Lava Ultimate and Vita Enamic were least sensitive. Artificial toothbrushing and storage generally resulted in a decrease in VHN and EIT for Paradigm MZ100, Lava Ultimate, and Ambarino High-Class but not for Vita Enamic and Vitablocs Mark II. CONCLUSIONS: Tooth-colored CAD-CAM materials with lower VHN and EIT generally showed better polishability. However, these materials were more prone to degradation by artificial toothbrushing and water storage than materials with higher VHN and EIT.

Two-body wear performance of dental colored zirconia after different surface treatments.

STATEMENT OF PROBLEM: Colored zirconia is widely used in dental clinical practice; however, data pertaining to its wear resistance after different surface treatments are sparse. PURPOSE: The purpose of this in vitro study was to evaluate the 2-body wear resistance of dental colored zirconia after different glazing and polishing treatments. MATERIAL AND METHODS: Standardized specimens were prepared from dental zirconia (internal and external staining and no staining) and subjected to different surface treatments. The stained zirconia and control ceramics were polished with a Robinson brush and polishing paste or polishing kits, while the nonstained zirconia was airborne-particle abraded and glazed. The specimens were then abraded against steatite antagonists using a pin-on-disk wear tester. The wear depth for the specimens was measured using confocal microscopy. Wear areas on the steatite antagonists were measured by using an optical microscope. Scanning electron microscopy (SEM) was used to evaluate the wear pattern of the zirconia specimens. All data were statistically analyzed with 1-way ANOVA and the Tamhane test for post hoc analysis (α=.05). RESULTS: The surfaces polished using the Robinson brush and paste showed no wear. The wear depth of the unglazed surfaces was 42.27 ±3.21 ∼84.15 ±2.57 µm and 87.75 ±9.36 and 91.76 ±13.58 µm for the glazed surfaces. The antagonist wear area was 1.79 ±0.21 ∼2.69 ±0.34 mm2 (unglazed) and 3.34 ±0.29 ∼4.51 ±0.88 mm2 (glazed). SEM revealed chipping fractures, and peeling cracks were observed on the glazed zirconia surfaces, indicating a combination of fatigue and abrasive wear. CONCLUSIONS: The results of this in vitro study suggest that highly polished zirconia shows the least wear, including antagonist wear. Furthermore, glazed zirconia can be significantly more abrasive than polished zirconia. The wear properties of internally and externally stained zirconia are similar.

Enamel demineralization after different methods of interproximal polishing.

OBJECTIVES: The aim of this in vitro study was to investigate the demineralization rate in human enamel after interproximal polishing (IPP) and to detect possible correlations with the IPP method used, with special emphasis on the surface characteristics of the enamel being treated. MATERIALS AND METHODS: This in vitro study tested five IPP systems (Profin Directional System®, Intensiv ProxoStrip®, OS discs®, ARS Safe-Tipped Bur Kit® and Ortho-Strips Set®) that are currently available on the market. Each of the five examination groups comprised 12 randomly selected teeth, while the control group consisted of six teeth. The teeth were placed in an artificial model for each group. The proximal contacts were then resolved by IPP. To allow detection of any surface characteristics, one surface was not further processed after IPP, while the other side was additionally polished. After IPP, the teeth were exposed to a pH-cycling model with alternating phases of demineralization and remineralization. Substance loss was analyzed using optical emission spectrometry. Data were subjected to simple analysis of variance (ANOVA) performed with Tukey's test. Comparison between the groups with and without polishing was conducted using the t test for independent samples. The significance level was set at p < 0.05. RESULTS: Demineralization significantly increased after IPP. The rates of demineralization differed significantly among the examination groups, with the greatest loss of substance being produced with Sheridan's Air-Rotor Stripping® system (ARS; 145.34 ± 20.37 µm). In all of the examination groups, subsequent polishing of the surfaces did not significantly reduce the amount of demineralization (polished 119.64 ± 28.61 µm; unpolished 114.16 ± 28.61 µm). CONCLUSION: No correlation between surface morphology and the degree of susceptibility of human enamel was detected. However, it must be taken into consideration that there was no potential bacterial colonization in this in vitro erosive set-up. Thus, in contrast to previous explanations, the outermost fluorapatite layer and the individual composition of the enamel may have a greater impact on the solubility of the enamel and the amount of enamel loss after IPP than the type of system used and the resulting surface texture. CLINICAL RELEVANCE: Whenever the outermost layer of enamel is reduced, the practitioner must expect an increase in demineralization. Subsequent polishing does not appear to affect the amount of demineralization.

Analysis of the effects of air polishing powders containing sodium bicarbonate and glycine on human teeth.

OBJECTIVES: The aim of this study was an analysis of the root surface roughness caused by air polishing powders containing sodium bicarbonate or glycine. METHODS: The roots of human molars were sectioned into dentin discs and irradiated with three different powders: (A) sodium bicarbonate (dv50 = 62 µm), (B) glycine (dv50 = 49 µm) and (C) glycine (dv50 = 21 µm). Standardized conditions in terms of instrumentation time (5 and 10 s), pressure (1.8 bar), distance (2 and 5 mm) and angulation (45° and 90°) were applied. Surface roughness (DIN EN ISO 4287:1998) of the probes was analysed by means of the surface profile values "Pa" and "Pt" and the surface roughness value "Rz". The effect of treatment (treated vs. untreated) was studied on each disc. Geometric mean ratios (GMRs) from mixed effects models and confidence intervals (95% CI) were calculated. RESULTS: For Pa, the comparison revealed significant differences between powders A and B (GMR 3.57, 95 % CI 2.87-4.43, p < 0.001) and powders A and C (GMR 2.72, 95% CI 2.20-3.37, p < 0.001) for the overall effects. With respect to Pt, significant differences occurred between powders A and B (GMR 2.49, 95% CI 2.11-2.94, p < 0.001) and powders A and C (GMR 2.39, 95% CI 2.03-2.82, p < 0.001). Between powders B and C, there were no significant differences for Pa, Rz and Pt. CONCLUSION: Air polishing powders containing glycine caused significantly less alterations on human root surfaces compared to powders containing sodium bicarbonate. CLINICAL SIGNIFICANCE: Powders containing glycine caused a significantly lower increase in root surface roughness compared to those containing sodium bicarbonate. Powders containing sodium bicarbonate may not be indicated for root surface treatment.

Insufficient evidence to determine the effects of routine scale and polish treatments.

DATA SOURCES: The Cochrane Oral Health Group's Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), Medline, Embase, the metaRegister of Controlled Trials and the US National Institutes of Health Clinical Trials Register. STUDY SELECTION: Randomised controlled trials (excluding split mouth) of routine scale and polish treatments with and without OHI in healthy dentate adults without severe periodontitis. DATA EXTRACTION AND SYNTHESIS: Study assessment, data extraction and risk of bias assessment were carried out independently by two reviewers. Mean and standardised mean differences were calculated when different scales were reported. Fixed effects models were used as there were only a small number of studies. RESULTS: Three studies involving a total of 837 patients, and all considered to be at unclear risk of bias were included. No studies reported any adverse effects. Only one trial (conducted in general practice) provided data comparing scale and polish versus no scale and polish. It found no evidence to claim or refute benefit for scale and polish treatments for the outcomes of gingivitis, calculus and plaque. Two studies, both at unclear risk of bias, compared routine scale and polish provided at different time intervals. When comparing six with 12 months there was insufficient evidence to determine a difference for gingivitis at 24 months. There were some statistically significant differences in favour of scaling and polishing provided at more frequent intervals, in particular between three and 12 months for the outcome of gingivitis at 24 months, with OHI, MD -0.14 (95% CI -0.23 to -0.05; P value = 0.003) and without OHI MD -0.21 (95% CI -0.30 to -0.12; P value < 0.001) (mean per patient measured on 0-3 scale), based on one study. There was some evidence of a reduction in calculus. This body of evidence was assessed as of low quality.One study provided data for the comparison of scale and polish treatment with and without OHI. There was a reduction in gingivitis for the 12-month scale and polish treatment when assessed at 24 months MD -0.14 (95% CI -0.22 to -0.06) in favour of including OHI. There were also significant reductions in plaque for both three and 12-month scale and polish treatments when OHI was included. The body of evidence was once again assessed as of low quality. CONCLUSIONS: There is insufficient evidence to determine the effects of routine scale and polish treatments. High quality trials conducted in general dental practice settings with sufficiently long follow-up periods (five years or more) are required to address the objectives of this review.

Comparison to the scanning electron microscope of professional dental hygiene methods on metal-free layered structures and metal-free monolithic structures processed by different polymerization cycles.

AIM: Aim of the study was to find effective instrumental methodologies and procedures for scaling and deplaquing without compromising the structure of metal-free, monolithic lithium disilicate and layered zirconia prosthetics. METHODS: Of 14 decontaminated, extracted teeth in good anatomical condition, 7 veneers lithium disilicate monolithic and 7 layered zirconia crowns were prepared for testing and divided into 6 treatment groups. Each group was composed of a veneer and a crown. The division of the groups was carried out according to the type of treatment performed- instrumental carbon fiber and steel tips, prophylaxis paste with high and low RDA (Relative dentin abrasion), bicarbonate powder. Samples were examined and observed through a scanning electron microscope (SEM). Afterwards a detailed comparison of the images of treated and untreated samples was performed. The images were at the same magnification, thus showing the differences in the treated samples. RESULTS: The monolithic lithium disilicate presents minor damage to the surface but no excessive changes to the structure in general post treatment. The layered zirconia resulted in notable damage with evident abrasions on the layered ceramic structure after the use of ultrasound with a steel tip and air flow with bicarbonate. Carbon fibre tips and prophylaxis paste containing perlite and low RDA did not create notable changes to the properties of the materials in question. CONCLUSION: The results of the disilicate monolithic appear to show it to be a much more resistant material compared to layered zirconia in ceramic. Its resistance is demonstrated by the lack of notable damage in all the treatment groups.

Effect of finishing and polishing on surface roughness of composite resins after bleaching

AIM : To evaluate the influence of finishing and polishing techniques on the surface roughness of two composite resins (CRs) subjected to bleaching procedure. METHODS : Forty-eight CR specimens were divided into six groups (n=8). For G1 to G3, a microhybrid CR (Opallis; FGM) was used, and G4 to G6, received a nanohybrid CR (Brilliant NewLine; Coltène/Whaledent). All specimens were subjected to bleaching procedure with 35% hydrogen peroxide (two 45-min applications, with a 5-day interval). The surface roughness of all specimens was evaluated before and after the bleaching and/or finishing/polishing (Ra parameter) by a roughness meter. After bleaching, the groups were subjected to finishing and polishing procedures: G2 and G5 - felt discs + diamond pastes; and G3 and G6 - silicon rubber tips. The control groups (G1 and G4) had no finishing or polishing treatment after bleaching. Data were analyzed by ANOVA and Tukey's post-test, and t test for paired samples (a=0.05). RESULTS : bleaching treatment increased Ra values for the nanohybrid CR specimens, but both finishing/polishing techniques were able to reduce these values; for the microhybrid specimens, only finishing/polishing with silicon rubber tips decreased the roughness values. CONCLUSIONS : For both microhybrid and nanohybrid CRs, the silicon rubber tips were effective to reduce the surface roughness after bleaching procedure...

Routine scale and polish for periodontal health in adults.

BACKGROUND: Many dentists or hygienists provide scaling and polishing for patients at regular intervals, even if those patients are considered to be at low risk of developing periodontal disease. There is debate over the clinical effectiveness and cost effectiveness of 'routine scaling and polishing' and the 'optimal' frequency at which it should be provided for healthy adults.A 'routine scale and polish' treatment is defined as scaling or polishing or both of the crown and root surfaces of teeth to remove local irritational factors (plaque, calculus, debris and staining), that does not involve periodontal surgery or any form of adjunctive periodontal therapy such as the use of chemotherapeutic agents or root planing. OBJECTIVES: The objectives were: 1) to determine the beneficial and harmful effects of routine scaling and polishing for periodontal health; 2) to determine the beneficial and harmful effects of providing routine scaling and polishing at different time intervals on periodontal health; 3) to compare the effects of routine scaling and polishing with or without oral hygiene instruction (OHI) on periodontal health; and 4) to compare the effects of routine scaling and polishing provided by a dentist or dental care professional (dental therapist or dental hygienist) on periodontal health. SEARCH METHODS: We searched the following electronic databases: the Cochrane Oral Health Group's Trials Register (to 15 July 2013), CENTRAL (The Cochrane Library 2013, Issue 6), MEDLINE via OVID (1946 to 15 July 2013) and EMBASE via OVID (1980 to 15 July 2013). We searched the metaRegister of Controlled Trials and the US National Institutes of Health Clinical Trials Register (clinicaltrials.gov) for ongoing and completed studies to July 2013. There were no restrictions regarding language or date of publication. SELECTION CRITERIA: Randomised controlled trials of routine scale and polish treatments (excluding split-mouth trials) with and without OHI in healthy dentate adults, without severe periodontitis. DATA COLLECTION AND ANALYSIS: Two review authors screened the results of the searches against inclusion criteria, extracted data and assessed risk of bias independently and in duplicate. We calculated mean differences (MDs) (standardised mean differences (SMDs) when different scales were reported) and 95% confidence intervals (CIs) for continuous data and, where results were meta-analysed, we used a fixed-effect model as there were fewer than four studies. Study authors were contacted where possible and where deemed necessary for missing information. MAIN RESULTS: Three studies were included in this review with 836 participants included in the analyses. All three studies are assessed as at unclear risk of bias. The numerical results are only presented here for the primary outcome gingivitis. There were no useable data presented in the studies for the outcomes of attachment change and tooth loss. No studies reported any adverse effects.- Objective 1: Scale and polish versus no scale and polish Only one trial provided data for the comparison between scale and polish versus no scale and polish. This study was conducted in general practice and compared both six-monthly and 12-monthly scale and polish treatments with no treatment. This study showed no evidence to claim or refute benefit for scale and polish treatments for the outcomes of gingivitis, calculus and plaque. The MD for six-monthly scale and polish, for the percentage of index teeth with bleeding at 24 months was -2% (95% CI -10% to 6%; P value = 0.65), with 40% of the sites in the control group with bleeding. The MD for 12-monthly scale and polish was -1% (95% CI -9% to 7%; P value = 0.82). The body of evidence was assessed as of low quality.- Objective 2: Scale and polish at different time intervals Two studies, both at unclear risk of bias, compared routine scale and polish provided at different time intervals. When comparing six with 12 months there was insufficient evidence to determine a difference for gingivitis at 24 months SMD -0.08 (95% CI -0.27 to 0.10). There were some statistically significant differences in favour of scaling and polishing provided at more frequent intervals, in particular between three and 12 months for the outcome of gingivitis at 24 months, with OHI, MD -0.14 (95% CI -0.23 to -0.05; P value = 0.003) and without OHI MD -0.21 (95% CI -0.30 to -0.12; P value < 0.001) (mean per patient measured on 0-3 scale), based on one study. There was some evidence of a reduction in calculus. This body of evidence was assessed as of low quality.- Objective 3: Scale and polish with and without OHIOne study provided data for the comparison of scale and polish treatment with and without OHI. There was a reduction in gingivitis for the 12-month scale and polish treatment when assessed at 24 months MD -0.14 (95% CI -0.22 to -0.06) in favour of including OHI. There were also significant reductions in plaque for both three and 12-month scale and polish treatments when OHI was included. The body of evidence was once again assessed as of low quality.- Objective 4: Scale and polish provided by a dentist compared with a dental care professionalNo studies were found which compared the effects of routine scaling and polishing provided by a dentist or dental care professional (dental therapist or dental hygienist) on periodontal health. AUTHORS' CONCLUSIONS: There is insufficient evidence to determine the effects of routine scale and polish treatments. High quality trials conducted in general dental practice settings with sufficiently long follow-up periods (five years or more) are required to address the objectives of this review.