The Effect of Desensitizing Toothpastes and Coffee ...downloads.hindawi.com/journals/bmri/2018/9673562.pdf · BioMedResearchInternational oxalates, glutaraldehyde,andformaldehydeastubuleplugs

Research ArticleThe Effect of Desensitizing Toothpastes and Coffee Staining onthe Optical Properties of Natural Teeth and Microhybrid ResinComposites An In-Vitro Study

Sedanur Turgut 1 Hamiyet KJlJnccedil2 KJvanccedil Utku Ulusoy 3 and Bora Bagis 4

1PhD DDS Assoc Professor Dr Department of Prosthodontics Faculty of Dentistry Karadeniz Technical UniversityTrabzon Turkey

2PhD DDS Assist Professor Dr Department of Prosthodontics Faculty of Dentistry Bolu Abant Izzet Baysal UniversityBolu Turkey

3PhD DDS Private Practice Antalya Turkey4PhD DDS Professor Dr Department of Prosthodontics Faculty of Dentistry Izmir Katip Celebi University Izmir Turkey

Correspondence should be addressed to Bora Bagis bbagisyahoocom

Received 26 July 2018 Revised 7 November 2018 Accepted 6 December 2018 Published 23 December 2018

Academic Editor Andrea Scribante

Copyright copy 2018 Sedanur Turgut et alThis is an open access article distributed under the Creative Commons Attribution Licensewhich permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited

Objective To evaluate the effect of different desensitizing toothpastes and coffee staining on the discoloration rate of natural humantooth and composite materials Materials and Methods A total of 56 human teeth and 56 composite specimens were used Afterinitial color measurements were taken specimens and teeth were exposed to simulated toothbrushing with six desensitizingtoothpastes containing different active ingredients stannous fluoride strontium acetate potassium citrate and hydroxyapatitecetylpyridinium chloride arginine and novamin Specimens were then exposed to coffee staining Throughout the stainingprocedure the storing solution was refreshed every day and the specimens were brushed with the tested toothpastes Colormeasurements and changes were recorded at each stage and analyzed with one-way ANOVA Dunnett tests and paired samplet-test (plt005) ResultsThe largest color change was obtained with the stannous fluoride toothpaste after coffee staining for naturalteeth (26 Δ119864

00

lowast) and composite specimens (31 Δ11986400lowast) Coffee staining resulted in significant changes for Δ11986400lowast values of allgroups except for natural teeth brushed with a novamin-based (p= 006) toothpaste For composite specimens only the stannousfluoride and cetylpyridinium chloride-based toothpastes resulted in significant color changes relative to the control group ΔLlowast andΔblowast values were also increased after staining for all groups (plt005) Conclusions Desensitizing toothpastes alone did not causeperceptible color changes however in combination with coffee staining it tended to increased discoloration for both compositesand natural teeth

1 Introduction

Tooth hypersensitivity is a multifactorial condition typicallycharacterized by sharp and brief arising in response toevaporative thermal osmotic tactile or chemical stimulithat cannot be ascribed to any other form of dental defector disease [1] This clinically frequent oral health problemcan cause pain while breathing eating or toothbrushingand its prevalence has been measured as ranging from 3to 73 [2] The most commonly supported explanation

of hypersensitivity is the hydrodynamic theory suggestedby Brannstrom which assumes that painful stimulationincreases fluid flow within the dentinal tubules stimulat-ing baroreceptors and thus causing a neural signal and apainful sensation [3] Therefore ideal treatment for hyper-sensitivity should block the exposed dentinal tubules orreduce fluid flow within the dentinal tubules [4] Gener-ally accepted treatments are the application of a dentinsealer such as composite resin glass ionomer or the useof potassium salts calcium phosphate fluorides strontium

HindawiBioMed Research InternationalVolume 2018 Article ID 9673562 7 pageshttpsdoiorg10115520189673562

2 BioMed Research International

oxalates glutaraldehyde and formaldehyde as tubule plugs[5] Alternative treatments are laser treatment or mucogin-gival plastic surgery [2] Sensitivity-relief toothpaste offersa convenient easy-to-use cost-effective and noninvasivemethod of healing sensitivity Various sensitivity-relief tooth-pastes are available worldwide which include as active agentssodium fluoride (NaF) stannous fluoride (SnF

2) arginine

potassium strontium or sodium calcium phosphosilicate[6 7]

Natural teeth and restorative materials suffer stainingdue to both extrinsic and intrinsic factors Extrinsic factorsmainly include biofilm accumulation smoking or consump-tion of staining beverages [8] The oral environment isexposed daily to a variety of media that have the potentialto cause discoloration resulting in esthetic problems Manystudies have examined the discoloration effects of various fac-tors [9] Moreover despite the importance of toothbrushingfor optimal oral hygiene the discoloration effect of brushingon the dental structures has been noted [10 11] Althoughextrinsic stains can be removed partially or totally from thedental surface by toothbrushing [11 12] the abrasion causedby brushing may result in gradual loss of enamel dentin andrestorative materials [13ndash18] which can increase the surfaceroughness resulting to become more susceptible to staining[19ndash21]

Discoloration can be evaluated visually or with color-measuring devices such as colorimeters which can provideaccurate numerical color data [22] Color difference (ΔE)indicates whether a change in overall shade is able to beperceived by a human eye [23] Sharma has calculated theCIEDE2000 color difference (Δ11986400lowast) by using an Excelspreadsheet implementation [24] This formula was foundconsiderably more sophisticated providing better indicatorsof human perceptibility and acceptability of color differ-ences and computationally involved than the equationsfor CIELab Δ119864lowast119886119887 and the CIE94 color difference [23ndash25] The CIEDE2000 formula includes not only lightnesschroma and hue weighting functions but also an interactiveterm between chroma and hue differences and seems tooffer improvements over the CIELab formula that wouldimply better clinical relevance [20] Perceptibility threshold(PT) and acceptability threshold (AT) are major thresholdsfor evaluating color differences and serve as a control toassess the dental materials success and interpret visual andinstrumental findings as reported by Pravina et al [23] ThePT represents the judgment of the presenceabsence of exactmatch with a color difference at or below it being a nearlyperfect color match However the PT is of limited practicalrelevance as industry rarely strive or need to achieve an exactmatch which would be time consuming and expensive TheAT defines the overall acceptance of color matchmismatchrepresenting the industry tolerance between the PT and theunacceptable mismatch Consequently an acceptable matchin dentistry is a color difference at or below the AT [23] Inthe previous studies the Δ119864

00

lowast values were compared with5050 PT and 5050 AT values [23 25ndash27]

Although the effect of toothbrushing on surface dete-rioration roughness and color changes have been studied[28 29] the effect of sensitivity-relief toothpastes on staining

of the natural human tooth and esthetic restorative materialshas not been reported The objectives of this study were toassess the effect of commonly used desensitizing toothpastescontaining different ingredients on the optical propertiesof natural tooth and resin composites after immersion incoffee over a six-month period The null hypotheses werethat brushing with desensitizing toothpastes would not causestaining and would not affect the optical properties of naturaltooth and resin composite materials after submitting to coffeestaining

2 Materials and Methods

21 Preparation of Specimens For the resin composite groupa total of 56 disk-shaped specimens were obtained using abrass mold with a socket (10 plusmn 005 mm diameter and 2plusmn 005 mm thickness) The microhybrid composite (GradiaDirect X GC) material was manipulated and polymerizedby covering the top surface with a glass slide and lightcuring (Elipar FreeLight 2 3MESPE) for 20 s perpendicularlyAfter removal from themold the specimens were light-curedfrom the bottom surface using the same parameters Thenspecimens were polished with silicon carbide (SiC) papers(Norton abrasives Guarulhos) of decreasing abrasiveness(600 1200 and 2000 grit) for 10 sec each by one clinicianThe specimens were measured at 3 points with a digitalmicrometer to ensure a standard thickness and if necessarythey were reproduced The specimens were divided intoseven groups randomly and stored at 37∘C and 100 relativehumidity for 24 hours before initial color measurements

For the natural tooth group a total of 56 human centralincisors recently extracted for periodontal reasons wereselected (use of natural teeth required ethics approval votenumber 201557)The teethwere stored in a 01 thymol solu-tion at room temperature for up to 4 weeks after extractionTeeth with any visible caries cracks or hypoplastic defectswere excluded All teeth were gently polished by one clinicianwith a rubber cup and polishing paste (CleanPolish Kerr)under running water for twominutesThe crowns of the teethwere then sectioned 2 mm apically to the cementoenameljunction using double-faced diamond discs under runningwater (KG Sorensen Barueri) The pulp tissues of the crownwere removed with hand instruments cleaned and thendivided into seven experimental procedure groups (n= 8)Before the baseline measurements were taken specimenswere immersed in artificial saliva at 37∘C for 24 hoursThe artificial saliva was prepared according to the followingformula 43 g xylitol 1 g sodium carboxymethylcellulose5 mg calcium chloride 40 mg potassium 01 g potassiumchloride phosphate 1 mg potassium thiocyanate and 100 gdeionized water

22 Color Measurement The Commission Internationale delrsquoEclairage (CIE) color measurements were obtained with acolorimeter (ShadeNCC Shofu) in a viewing booth underD65 standard illumination based on ISO standards (ISO7491)The colorimeter was calibrated according to the manu-facturer instructions before the experimental measurements

BioMed Research International 3

and the probe tip was positioned perpendicular in themiddle of each specimen according to a previous article[14] The Llowastalowastblowast color notation of each composite and toothwere measured consecutively three times against a whitebackground (119871lowast=9668 119886lowast=minus018 119887lowast=minus022) and the averageof the readings calculated [30] The Llowast value measures thelightness or brightness of a material alowast is a measure of green-ness (negative) or redness (positive) and blowast is a measure

of blueness (negative) or yellowness (positive) [31] Afterthe simulated tooth brushing and discoloration procedurecolor coordinates of the specimens were again measuredunder the same conditions as before The Δ119864

00

lowast values werecalculated from the CIELab color space Given a pair of colorvalues in CIELab color space L

0

lowast a0

lowast b0

lowast and L1

lowast a1

lowastb1

lowast and color differences were calculated with the followingformula

ΔElowast00= radic( Δ1198711015840119896119871119878119871)

2 + ( Δ1198621015840119896119862119878119862)2 + ( Δ1198671015840119896119867119878119867)

2 + 119877119879( Δ1198621015840119896119862119878119862)2 ( Δ1198671015840119896119867119878119867)

2

(1)

For a pair of specimens ΔCrsquo and ΔHrsquo are the differencesin chroma and hue S

119871 S119862 and S

119867are the weighting functions

for the lightness chroma and hue and k119871 k119862 and k119867 are theparametric weighting factors for variations in experimentalconditions RT is a rotation function and applied to accountfor the interaction between hue and chroma differences in theblue region The parametric factors were set to 1 [24]

23 Simulated Toothbrushing After the initial color mea-surements were taken the labial surfaces of the naturalteeth and the composite surfaces were exposed to simulatedtoothbrushing using an electronic toothbrush (Braun Oral-B Advance Power) and soft toothbrushes (Oral-B SensitiveClean ProcterampGamble) Specimens were fixed horizontallyface-side-up and each brush set to result in a final weight of200 g The toothpaste slurry was prepared in a proportionof 11 by weight (150 g of toothpaste and 150 ml of artificialsaliva) Six different desensitizing toothpastes were used forthe present study and no toothpaste was used for the control(C) group (Table 1) Artificial saliva was prepared accordingto the formula described in the preparation of specimenssection above Each specimen was brushed daily using 40strokes This number was based on an estimate that a toothis brushed for 10 seconds in each daily toothbrushing of 2minutes [10] Considering that toothbrushing is performedtwice a day this means that each tooth will be submittedon average to 280 strokes weekly (2 strokes per second1120strokes in a mounth) resulting 6720 strokes for 6 monthsAfter every 1200 strokes brushes and toothpastes werereplaced and freshly mixed toothpaste slurries applied Thiscycle was repeated for each toothpaste

Specimens were then taken from the sample holderswashed for 1 minute with an airwater spray and put in anultrasonic cleaner for 10minutes after which theywerewipeddry with tissue paper The specimens were re-evaluated fortheir color measurements and color changes (Δ119864

00

lowast

1) were

recorded

24 Discoloration Procedure After the simulated toothbrush-ing and measurement of color values the specimens wereexposed to staining The staining solution was prepared byadding 75 g coffee (Nescafe Classic Nestle) to 500 ml boilingdistilled water All specimens were immersed in the coffee

solution in a stainless steel container in a dark environmentand stored at 37∘C for seven days to simulate intra-oral con-ditions Throughout the experiment every day the stainingsolution was refreshed and the specimens were brushed withthe study toothpastes After the discoloration procedure eachspecimen was washed and dried Color measurements weretaken for each specimen under the process described aboveand the data were recorded as L

2

lowast a2

lowast and b2

lowast Color changes(Δ11986400

lowast

2) were calculated using these new values and the

original values (L0

lowast a0

lowast and b0

lowast) (Table 2)

25 Statistical Analysis Statistical analyses were performedwith SPSS for Windows 170 (SPSS Inc Chicago IL USA)Statistical analyses were performed with SPSS for Windows170 Shapiro wilk test was used for normality of distributionPaired sample t-test was used for evaluating tested variables(Δ11986400

lowast

1-Δ11986400

lowast

2 ΔLlowast1- ΔLlowast

2 Δalowast1- Δalowast2 and Δblowast

1- Δblowast

2)

One-way analysis of variance (ANOVA) and Dunnettrsquos testswere used for comparing the experimental groups with thecontrol group separately for individual materials (naturalteeth and composites) plt005 was set as significance level3 Results

Evaluating the ΔE00

lowast

1 ΔE00

lowast

2 ΔL1

lowast ΔL2

lowast Δa1

lowast Δa2

lowastΔb1

lowast and Δb2

lowast values the results of the one-way ANOVAand Dunnettrsquos tests indicated that there were significantdifferences for both natural teeth and the composite groupsafter coffee stainingThemeans standard deviations (SD) andstatistical significance of ΔE

00

lowast

1 ΔE00

lowast

2 ΔL1

lowast ΔL2

lowast Δa1

lowastΔa2

lowast Δb1

lowast and Δb2

lowast values are shown in Tables 3 and 4For natural teeth the mean values of ΔE

00

lowast

1ranged

between 03 and 11 while ΔE00

lowast

2values ranged between 10

and 26 The highest ΔElowast was obtained by Group SF aftercoffee staining (ΔE

00

lowast

2=26) There were significant differ-

ences between the ΔE00

lowast

1and ΔE

00

lowast

2values for all groups

(plt005) except Group N (p= 006) Control group resultedin significantly lower ΔE

00

lowast

1value than other groups Evalu-

ating the ΔE00

lowast

2values with the control group no significant

differences were found for Group N (p=009)ΔL2

lowast and Δb2

lowast

values of all groups were significantly higher than ΔL1

lowast andΔb1

lowast values For Δa1

lowast there were no significant differencesfor Group SF (p=0207) and Group PcH (p=006)


Table 1 Sensitive-relief toothpastes used in the study

Toothpaste Manufacturer Active ingredientsProexpert Clinic LineSensitive (SF) Ipana Stannous floride

(1450 ppm fluoride)

Sensodyne Rapid Relief (SA) Sensodyne Strontium acetate(1040 ppm fluoride)

Signal Sensitive Expert(PcH) Unilever

Potassium citratehydroxyapatite

(1450 ppm fluoride)

GUM Paroex Sensivital(CPC) Sunstar GUM

Cetylpyridiniumchloride

(950 ppm fluoride)Colgate Sensitive Pro-Relief(A)

Colgate-Palmolive

Arginine(1450 ppm fluoride)

Sensodyne RepairampProtect(N) Sensodyne Novamin

(450 ppm fluoride)

Table 2 The study methodology

1 Specimen preparation (n=8)(natural toothcomposite)

5 Second color measurements(L1 a1 b1)darr darr

2 Storage in artificial saliva (24hr) 6 Evaluation of ΔE00lowast1darr darr

3 Initial color measurements(L0 a0 b0)

7 Staining with coffee brushingeach daydarr darr

4 Simulated brushing 8 Final color measurements(L2 a2 b2)darr

9 Evaluation of ΔE00

lowast

2

For composite specimens the mean values of ΔE00

lowast

1

ranged between 06 and 16 while ΔE00

lowast

2values ranged

between 21 and 31 Again the highest color change wasobtained by Group SF after coffee staining (ΔE

00

lowast

2=31)

Significant differences were also found between ΔE00

lowast

1andΔE

00

lowast

2for all experimental groups (plt005) For all exper-

imental procedures only Group SF (p=0003 for ΔE00

lowast

1

plt0001 for ΔE00

lowast

2) and Group CPC (p=0079 for ΔE

00

lowast

1

plt0602 for ΔE00

lowast

2) resulted in significant color changes

relative to the control groupPaired sample t-test also showed thatΔE

00

lowastΔLlowast andΔblowastvalues increased after coffee staining for all groups and theseincrements were statistically significant (plt005)There wereonly no significant differences for Δa

1

lowast- Δa2

lowast of Group SFfor composites (p= 0207) and Group PcH for natural teeth(p=006)

All groups recorded negative Llowast values and positive alowastand blowast values (Llowast values decreased and alowast and blowast valuesincreased) except Group N and Group C-Group N recordedpositive L

1

lowast and negative b1

lowast values (Llowast values increasedand blowast values decreased) for natural teeth after simulating

brushing whileGroupC recorded positiveL1

lowast andnegativeb1

lowast values (Llowast values increased and blowast values decreased) forboth natural teeth and composite specimens

4 Discussion

The first null hypothesis of the study was partially rejectedsignificant differences were found between the color changevalues of natural teeth and composite materials after usingdesensitizing toothpastes for six months The second nullhypothesis that desensitizing toothpastes would not affectstainability after coffee exposure was partially rejected fornatural teeth (GroupNdid not show significant color changesrelative to the control group) and rejected for compositematerials For all composite groups coffee staining increasedtheΔE

00

lowast values significantly Color changes were slighter fornatural teeth for all evaluated groups

As reported in a previous study [32] the different toler-ance could be expected when compared with the color differ-ences derived mostly from the differences in chroma Severalstudies [23 25ndash27] determined that 5050 PT ranged from080 to 130 ΔE

00

lowast units and that 5050AT ranged from 180to 225 ΔE

00

lowast Paravina et al [23] have found 5050 PT andATs were significantly different CIEDE2000 5050 PT was08ΔE

00

lowast whereas 5050ATwas 18ΔE00

lowast In this study thecolor differences were beyond those values of 5050 PT forboth natural teeth and composites after simulated brushingand coffee staining Evaluating the 5050 AT Groups SFSA and CPC exhibited higher ΔE

00

lowast values for natural teethHowever for composites none of the groups were below thevalues of 5050 AT

Several in vitro studies have shown that topically appliedfluoride agents may cause volume loss and surface changesin restorative materials such as resin or ceramics [13 33]High fluoride concentrations have been shown to causemore significant surface damageThe most common fluorideagents currently in use are 04 SnF

2and 10 NaF gel

04 SnF2concentration has a pH of 32 making it more

acidic than 10 NaF and this low pH may cause surfacedeterioration [33] One study found that NaF caused lesssurface deterioration and discoloration for porcelain thanSnF2after one year of clinical exposure [33] Other researchs

have also reported that stannous formulations have a possiblestaining side effect [19 20] Significant tooth staining may bethe result of stannous fluoride that generally causes productsto be unstable Hence this ingredient is not favored for use inbleaching agents [6]

Therefore the fact that Group SF experienced the highestdiscoloration in this study might be attributable to possibledamage of the surfaces of both natural teeth and compositesThe discoloration also may occur as a result of using the SnF

2

formulationIn this study both natural teeth and the composite

specimens that were exposed to simulated brushing withdesensitizing toothpastes and coffee became darker andmoreyellow Only novamin-containing toothpaste caused bothnatural teeth and the composites to become brighter (ieincreased the Llowast value) Novamin is an amorphous calcium


Table 3 Color differences of natural teeth after brushing and staining with coffee

Group SF Group SA Group PcH Group CPC Group A Group N Group CΔE00

lowast

111 plusmn 03c 08 plusmn 01cb 06 plusmn 01b 08 plusmn 01cb 08 plusmn 03cb 06 plusmn 01b 03 plusmn 02aΔE

00

lowast

226 plusmn 04ex 21 plusmn 02fx 17 plusmn 03dx 25 plusmn 03ex 16 plusmn 03dx 10plusmn 02c 11 plusmn 03cxΔL

1

lowast 12 plusmn 03c 08 plusmn 01b 07 plusmn 01b 08 plusmn 03b 10 plusmn 01bc 09 plusmn 03bc 04 plusmn 01aΔL2

lowast 29 plusmn 03dx 23 plusmn 01cx 17 plusmn 03bx 27 plusmn 02dx 21 plusmn 01cx 12 plusmn 02ax 10 plusmn 01axΔa1

lowast 02 plusmn 01a 03 plusmn 02a 01 plusmn 01a 02 plusmn 02a 0 plusmn 01a 0 plusmn 01a 01 plusmn 02aΔa2lowast 05 plusmn 03abx 04 plusmn 01ax 03 plusmn 01a 06 plusmn 01bx 06 plusmn 02bx 01 plusmn 01ax 03 plusmn 01axΔb1

lowast 11 plusmn 04b 08 plusmn 02b 05 plusmn 01a 1 plusmn 02b 04 plusmn 02a 03 plusmn 02a 03 plusmn 02aΔb2

lowast 26 plusmn 03cdx 20 plusmn 01dx 18 plusmn 02dx 25 plusmn 03cx 14 plusmn 02adx 08 plusmn 01bx 12 plusmn 03axNote x=significant differences between the ΔE00lowast1 - ΔE00

lowast

2 ΔL1lowast - ΔL2lowast Δa1lowast - Δa2lowast and Δb1lowast - Δb2lowast values (plt005) same superscript letters in the same

row indicate no significant differences between the groups (pgt005)

Table 4 Color differences of composites after brushing and staining with coffee


lowast

116plusmn02a 12plusmn02b 13plusmn01b 08plusmn01c 07plusmn01c 06plusmn01c 11plusmn01bcΔE

00

lowast

231plusmn02ax 27plusmn01acdx 23plusmn02bcdx 28plusmn02acx 26plusmn02acdx 21plusmn02bdx 22plusmn02dxΔL

1

lowast 15 plusmn 05a 13 plusmn 02a 11 plusmn 04abc 08 plusmn 01b 10 plusmn 02bc 09 plusmn 02bc 04 plusmn 01bΔL2

lowast 31 plusmn 04ax 29 plusmn 03bx 19 plusmn 03ax 30 plusmn 02abx 26 plusmn 04 18 plusmn 03bx 18 plusmn 02bxΔa1

lowast 06 plusmn 02a 07 plusmn 02a 03 plusmn 02b 02 plusmn 01b 0 plusmn 02b 0 plusmn 03b 01 plusmn 02bΔa2

lowast 11 plusmn 03a 04 plusmn 04bx 06 plusmn 03bx 08 plusmn 03abx 08 plusmn 03abx 04 plusmn 02bx 04 plusmn 02bxΔb1

lowast 18 plusmn 03a 11 plusmn 05bc 15 plusmn 04ab 1 plusmn 02c 04 plusmn 02d 03 plusmn 02d 03 plusmn 02dΔb2

lowast 33 plusmn 03ax 31 plusmn 02abx 29 plusmn 04bx 31 plusmn 04abx 32 plusmn 06abx 27 plusmn 03bx 28 plusmn 04bxNote x = significant differences between the ΔE00

lowast

1- ΔE00

lowast

2 ΔL1lowast - ΔL2

lowast Δa1lowast - Δa2

lowast and Δb1lowast - Δb2

lowast values (p lt 005) same superscript letters in thesame row indicate no significant differences between the groups (p gt 005)

sodium phosphosilicate that reacts in aqueous environmentsto release calcium phosphate and sodium ions over timeThisinorganic compound was developed as a bone-regenerativematerial but has also shown to be combined with tooth dueto its high affinity with collagen when exposed to saliva emit-ting phosphate and calcium through the development of ahydroxyapatite-likemineral layerNovamin allows phosphateand calcium to be released from the surface These crystalsare known to fill in microscopic surface defects makingteeth stronger smoother and less sensitive This agent alsominimizes surface protein precipitation that can limit theability of chromagens to bind to teeth over time [7]

Roselino et al [11] reported that dentifrice abrasivenessdid not interfere with the ability to remove stains fromaged composites The authors also claimed that staining ismaterial-dependent Other studies have researched tooth-brushing has an effect on optical properties and surfaceroughness of esthetic dental materials [9 10] Toothbrushabrasion however could cause wear of composite resins mostcommonly on the buccal surface [14] As smaller and morehomogeneous fillers of a material would reduce the amountof exposed organic matrix material type surface-finishingtechniques composite particle size distribution and homo-geneity might also influence these results decreasing wearafter brushing [23] The oxidation of amine accelerators inthe composite material can cause discoloration changing huefrom a whitish to a yellow appearance Exogenous sourcessuch as coffee tea and nicotine are factors of extrinsicdiscoloration and these factors may be responsible for visibly

detectable or esthetically unacceptable color changes in den-tal materials or natural tooth [21] Perceptible color changeswere also observed in the present study for some groups afterthe experimental procedures (Tables 3 and 4)

The extrinsic staining of natural teeth is mainly explainedby incorporation of chromogens into the pellicle layer Otherstudies have reported that naked enamel will experience littlestaining even when exposed continuously to tea solutionsfor 24 hours or more [21] Major contributors to stainingof dentation are thought to be the beverages including teacoffee and cola Staining can occur via different mechanismsfor example discoloration caused by coffee occurs by boththe adsorption and absorption of colorants so the degreeof staining varies Chan et al [21] investigated the stainingpotential of beverages on different composite resins anddeclared that the greatest amount of discoloration occursduring the first week with results in this time period differingsignificantly from all succeeding weeks It is for this reasonthat in order to determine the potential for long-term stainretention an immersion time of one week was chosen in thepresent study

In the present study artificial saliva was used to stor-ing natural teeth and composite specimens before colormeasurements The deposition of stains and the subsequentaccumulation of artificial saliva act as amatrix andmay resultin discoloration [9]However the current study only capturedthe impact of coffee on the salivary pellicle Other dietaryagents that might affect the surfaces of teeth and dentalmaterials and hence staining should also be considered The


action of toothbrushing associatedwith the use of toothpasteshas been shown to be responsible for an increase in surfaceroughness in composite resins [11] In the present studythe composites showed perceptible color changes after thestaining procedures This result might be attributable tothe simulated brushing which resulted in varying degreesof roughness However using sensitivity-relief toothpastesincreased the staining level (except for Group N) whichmight be due to the possible staining effects of the ingredientsin these toothpastes Since composite specimens resulted inhigher E

00

lowast values than natural teeth clinicians should beaware of discoloration effect of resin restorative materialsespecially when using in the anterior region where thepossible discolorations will be most noticeable

Dentists often recommend toothbrushes with soft bristlesfor patients with sensitive teeth As the present study wasdesigned to test toothpastes for sensitive teeth the specimenswere brushed with soft brushes There is still controversy inthe literature surrounding cleaning and abrasionwith hard vssoft bristles however Zimmer et al [12] demonstrated bettercleaning was possible with hard filaments as compared withsoft ones This may have effected the clinically imperceptiblediscoloration for both natural teeth and composites in thepresent study as the soft brushes might not have been ableto clean the surfaces sufficiently

In one study [10] the roughness and optical stability(color translucency and gloss) of microfilled microhybridand nanofilled-composites submitted to simulated tooth-brushing over a period of 10 weeks were evaluated As aresult authors reported that toothbrushing increased theroughness and diminished the gloss of the resins In thecurrent study microhybrid composite is preferred by authorsbecause it is the most used resin material type for anteriorrestorations by the clinicians [34] and it was aimed toevaluate the optical properties of natural anterior humanteeth and resin restorative material applicable in the ante-rior region where the possible discolorations will be mostnoticeable

In Bernardon et al [18] the effect of desensitizing denti-frices on dentin wear was evaluated and the results showedthat all dentifrices cause a progressive increase in surfaceloss over time However no significant differences amongdentifrices were observed Another study demonstrated thatafter 10 hours of simulated toothbrushing ceramic surfacesexhibited no or little damage while composite materialsexhibited surface deterioration [16]The effect of toothbrush-ing on the deterioration of resin materials resulted in a rapidincrease in the surface roughness with the extent dependingon the material Results cannot be easily compared as thesestudies were conducted on the basis on different designparameters such as loading number of strokes toothbrushand toothpaste However the results of the present studyindicate that using sensitivity-relief toothpastes for up to sixmonths might cause discoloration for both natural teeth andcomposite materials and the amount of staining might differdepending on the toothpastersquos ingredients

Limitations of this study include the possible impactson results of different dietary factors and more frequentoral hygiene procedures Furthermore flat-surface composite

specimens were used in this study which may have affectedpropensity to stain Color measurements were done using acolorimeter in the present study However when measuringthe color of translucent dental materials small aperturecolorimeters are prone to the edge-loss effect Edge-losseffect generally occurs when illumination and color measure-ment are made through the same window Because of thetranslucency of the materials illuminating light sent fromthe device can be absorbed transmitted scattered reflectedand displaced in different directions [22] However when thespecimens were prepared with a greater diameter than themeasurement tip diameter the possible effects of edge-losscan be minimized [31]

As material surface can affect the staining procedureproperly further research is required to evaluate the surfacetopography of both composites and natural teeth which havebeen exhibited to brushing with desensitizing toothpastesusing different type of toothbrushes over a long period

5 Conclusions

Within the limitations of the present study the followingconclusions were drawn

Desensitizing toothpastes used in the study for sixmonths cause color changes below the values of 5050 ATbefore coffee staining

Usage of desensitizing toothpastes increased the amountof discoloration after storing in coffee for both compositesand natural teeth except for the novamin-containing tooth-paste

For natural teeth and composites desensitizing tooth-pastes containing SF SA or CPC cause color changes abovethe values of 5050 AT after simulated brushing and coffeestaining

Using novamin-containing toothpastes caused the natu-ral teeth and composites to becomebrighter and redder whilethe other desensitizing toothpastes diminished brightnessand increased yellowness

Data Availability

The data used to support the findings of this study areavailable from the corresponding author upon request

Conflicts of Interest

The authors declare that they have no conflicts of interest

References

[1] N X West ldquoDentine hypersensitivityrdquo Monographs in oralscience vol 20 pp 173ndash189 2006

[2] H J Shiau ldquoDentin hypersensitivityrdquo Journal of Evidence-BasedDental Practice vol 12 no 3 pp 220ndash228 2012

[3] M Brannstrom ldquoEtiology of dentin hypersensitivityrdquo Proc FinnDent Soc vol 88 7 p 13 1992

[4] D Cummins ldquoDentin hypersensitivity from diagnosis to abreakthrough therapy for everyday sensitivity reliefrdquo Journal ofClinical Dentistry vol 20 no 1 pp 1ndash9 2009


[5] D Sharma J A McGuire J T Gallob and P Amini ldquoRan-domised clinical efficacy trial of potassium oxalate mouthrinsein relieving dentinal sensitivityrdquo Journal of Dentistry vol 41 no4 pp S40ndashS48 2013

[6] L Y Tay C Kose A D Loguercio and A Reis ldquoAssessingthe effect of a desensitizing agent used before in-office toothbleachingrdquoThe Journal of the American Dental Association vol140 no 10 pp 1245ndash1251 2009

[7] L Gendreau A P S Barlow and S C Mason ldquoOverview of theclinical evidence for the use of NovaMin in providing relieffrom the pain of dentin hypersensitivityrdquo Journal of ClinicalDentistry vol 22 no 3 pp 90ndash95 2011

[8] J-H Bae Y-K Kim and S-K Myung ldquoDesensitizing tooth-paste versus placebo for dentin hypersensitivity A systematicreview and meta-analysisrdquo Journal of Clinical Periodontologyvol 42 no 2 pp 131ndash141 2015

[9] F De Carvalho Panzeri Pires-De-Souza L D F R Garcia LD M R Roselino and L Z Naves ldquoColor stability of silorane-based composites submitted to accelerated artificial ageing - Anin situ studyrdquo Journal of Dentistry vol 39 no 1 pp e18ndashe242011

[10] E M Da Silva J Doria J D J R Da Silva G V Santos JG A Guimaraes and L T Poskus ldquoLongitudinal evaluationof simulated toothbrushing on the roughness and opticalstability of microfilled microhybrid and nanofilled resin-basedcompositesrdquo Journal of Dentistry vol 41 no 11 pp 1081ndash10902013

[11] L M D R Roselino M A Chinelatti C C Alandia-Romanand F D C P Pires-de-souza ldquoEffect of brushing time anddentifrice abrasiveness on color change and surface roughnessof resin compositesrdquo Brazilian Dental Journal vol 26 no 5 pp507ndash513 2015

[12] S Zimmer B Didner and J-F Roulet ldquoClinical study on theplaque-removing ability of a new triple-headed toothbrushrdquoJournal of Clinical Periodontology vol 26 no 5 pp 281ndash2851999

[13] K Kula and T J Kula ldquoThe effect of topical APF foam and otherfluorides on veneer porcelain surfacesrdquo Journal of PediatricDentistry vol 17 no 5 pp 356ndash361 1995

[14] S Turgut B Bagis E Aydogan Ayaz et al ldquoDiscoloration ofprovisional restorations after oral rinsesrdquo International Journalof Medical Sciences vol 10 no 11 pp 1503ndash1509 2013

[15] F C Garcia L Wang P H DrsquoAlpino J B Souza P A Araujoand R F Mondelli ldquoEvaluation of the roughness and massloss of the flowable composites after simulated toothbrushingabrasionrdquo Brazilian Oral Research vol 18 no 2 pp 156ndash1612004

[16] S D Heintze M Forjanic K Ohmiti and V Rousson ldquoSurfacedeterioration of dental materials after simulated toothbrushingin relation to brushing time and loadrdquoDental Materials vol 26no 4 pp 306ndash319 2010

[17] L Wang F C P Garcia P A De Araujo E B Franco and RF L Mondelli ldquoWear resistance of packable resin compositesafter simulated toothbrushing testrdquo Journal of Esthetic andRestorative Dentistry vol 16 no 5 pp 303ndash314 2004

[18] J K Bernardon M Vieira Martins G Branco Rauber SMonteiro Junior and L N Baratieri ldquoClinical evaluation ofdifferent desensitizing agents in home-bleaching gelsrdquo Journalof Prosthetic Dentistry vol 115 no 6 pp 692ndash696 2016

[19] K Lorenz B Noack N Herrmann and T Hoffmann ldquoToothstaining potential of experimental amine fluoridestannous

fluoride mouth rinse formulationsmdasha randomized crossoverforced staining studyrdquo Clinical Oral Investigations vol 19 no5 pp 1039ndash1045 2015

[20] S D Heintze and M Forjanic ldquoSurface roughness of differentdental materials before and after simulated toothbrushing invitrordquo Operative Dentistry vol 30 no 5 pp 617ndash626 2005

[21] K C Chan J L Fuller and A A Hormati ldquoThe ability offoods to stain two composite resinsrdquo The Journal of ProstheticDentistry vol 43 no 5 pp 542ndash545 1980

[22] F F Tung G R Goldstein S Jang and E Hittelman ldquoTherepeatability of an intraoral dental colorimeterrdquo Journal ofProsthetic Dentistry vol 88 no 6 pp 585ndash590 2002

[23] R D Paravina R Ghinea L J Herrera et al ldquoColor differencethresholds in dentistryrdquo Journal of Esthetic and RestorativeDentistry vol 27 no 1 pp S1ndashS9 2015

[24] G Sharma W Wu and E N Dalal ldquoThe CIEDE2000 color-difference formula implementation notes supplementary testdata and mathematical observationsrdquo Color Research amp Appli-cation vol 30 no 1 pp 21ndash30 2005

[25] R Ghinea M M Perez L J Herrera M J Rivas A Yebra andR D Paravina ldquoColor difference thresholds in dental ceramicsrdquoJournal of Dentistry vol 38 no 2 pp e57ndashe64 2010

[26] M DM Perez R Ghinea L J Herrera et al ldquoDental ceramicsa CIEDE2000 acceptability thresholds for lightness chroma andhue differencesrdquo Journal of Dentistry vol 39 no 3 pp e37ndashe442011

[27] B T Xu B Zhang Y Kang Y NWang andQ Li ldquoApplicabilityof CIELABCIEDE2000 formula in visual color assessments ofmetal ceramic restorationsrdquo Journal of Dentistry vol 40 no 1pp e3ndashe9 2012

[28] A A Baig K M Kozak E R Cox J R Zoladz L Mahony andD J White ldquoLaboratory Studies on the Chemical WhiteningEffects of a Sodium Hexametaphosphate Dentifricerdquo Journal ofClinical Dentistry vol 13 no 1 pp 19ndash24 2002

[29] N X West M Addy R Newcombe et al ldquoA randomisedcrossover trial to compare the potential of stannous fluoride andessential oil mouth rinses to induce tooth and tongue stainingrdquoClinical Oral Investigations vol 16 no 3 pp 821ndash826 2012

[30] S Turgut H Kilinc G B Eyuboglu and B Bagis ldquoColorrelationships of natural anterior teeth An In vivo studyrdquoNigerian Journal of Clinical Practice vol 21 pp 925ndash931 2018

[31] M R Luo G Cui and B Rigg ldquoThe development of the CIE2000 colour-difference formula CIEDE2000rdquoColor ResearchampApplication vol 26 no 5 pp 340ndash350 2001

[32] M Melgosa E Hita M M Perez and A El Moraghi ldquoSensi-tivity differences in Chroma Hue and Lightness from severalclassical threshold datasetsrdquo Color Research amp Application vol20 no 4 pp 220ndash225 1995

[33] I I Artopoulou J M Powers and M S Chambers ldquoIn vitrostaining effects of stannous fluoride and sodium fluoride onceramic materialrdquo Journal of Prosthetic Dentistry vol 103 no3 pp 163ndash169 2010

[34] F F Demarco R A Baldissera F C Madruga et al ldquoAnteriorcomposite restorations in clinical practice findings from asurvey with general dental practitionersrdquo Journal of AppliedOral Science vol 21 no 6 pp 497ndash504 2013

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BioMed Research InternationalMaterials

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nom

ate

ria

ls


Journal ofNanomaterials

Submit your manuscripts atwwwhindawicom


oxalates glutaraldehyde and formaldehyde as tubule plugs[5] Alternative treatments are laser treatment or mucogin-gival plastic surgery [2] Sensitivity-relief toothpaste offersa convenient easy-to-use cost-effective and noninvasivemethod of healing sensitivity Various sensitivity-relief tooth-pastes are available worldwide which include as active agentssodium fluoride (NaF) stannous fluoride (SnF

2) arginine

potassium strontium or sodium calcium phosphosilicate[6 7]

Natural teeth and restorative materials suffer stainingdue to both extrinsic and intrinsic factors Extrinsic factorsmainly include biofilm accumulation smoking or consump-tion of staining beverages [8] The oral environment isexposed daily to a variety of media that have the potentialto cause discoloration resulting in esthetic problems Manystudies have examined the discoloration effects of various fac-tors [9] Moreover despite the importance of toothbrushingfor optimal oral hygiene the discoloration effect of brushingon the dental structures has been noted [10 11] Althoughextrinsic stains can be removed partially or totally from thedental surface by toothbrushing [11 12] the abrasion causedby brushing may result in gradual loss of enamel dentin andrestorative materials [13ndash18] which can increase the surfaceroughness resulting to become more susceptible to staining[19ndash21]

Discoloration can be evaluated visually or with color-measuring devices such as colorimeters which can provideaccurate numerical color data [22] Color difference (ΔE)indicates whether a change in overall shade is able to beperceived by a human eye [23] Sharma has calculated theCIEDE2000 color difference (Δ11986400lowast) by using an Excelspreadsheet implementation [24] This formula was foundconsiderably more sophisticated providing better indicatorsof human perceptibility and acceptability of color differ-ences and computationally involved than the equationsfor CIELab Δ119864lowast119886119887 and the CIE94 color difference [23ndash25] The CIEDE2000 formula includes not only lightnesschroma and hue weighting functions but also an interactiveterm between chroma and hue differences and seems tooffer improvements over the CIELab formula that wouldimply better clinical relevance [20] Perceptibility threshold(PT) and acceptability threshold (AT) are major thresholdsfor evaluating color differences and serve as a control toassess the dental materials success and interpret visual andinstrumental findings as reported by Pravina et al [23] ThePT represents the judgment of the presenceabsence of exactmatch with a color difference at or below it being a nearlyperfect color match However the PT is of limited practicalrelevance as industry rarely strive or need to achieve an exactmatch which would be time consuming and expensive TheAT defines the overall acceptance of color matchmismatchrepresenting the industry tolerance between the PT and theunacceptable mismatch Consequently an acceptable matchin dentistry is a color difference at or below the AT [23] Inthe previous studies the Δ119864

00

lowast values were compared with5050 PT and 5050 AT values [23 25ndash27]

Although the effect of toothbrushing on surface dete-rioration roughness and color changes have been studied[28 29] the effect of sensitivity-relief toothpastes on staining

of the natural human tooth and esthetic restorative materialshas not been reported The objectives of this study were toassess the effect of commonly used desensitizing toothpastescontaining different ingredients on the optical propertiesof natural tooth and resin composites after immersion incoffee over a six-month period The null hypotheses werethat brushing with desensitizing toothpastes would not causestaining and would not affect the optical properties of naturaltooth and resin composite materials after submitting to coffeestaining

2 Materials and Methods

21 Preparation of Specimens For the resin composite groupa total of 56 disk-shaped specimens were obtained using abrass mold with a socket (10 plusmn 005 mm diameter and 2plusmn 005 mm thickness) The microhybrid composite (GradiaDirect X GC) material was manipulated and polymerizedby covering the top surface with a glass slide and lightcuring (Elipar FreeLight 2 3MESPE) for 20 s perpendicularlyAfter removal from themold the specimens were light-curedfrom the bottom surface using the same parameters Thenspecimens were polished with silicon carbide (SiC) papers(Norton abrasives Guarulhos) of decreasing abrasiveness(600 1200 and 2000 grit) for 10 sec each by one clinicianThe specimens were measured at 3 points with a digitalmicrometer to ensure a standard thickness and if necessarythey were reproduced The specimens were divided intoseven groups randomly and stored at 37∘C and 100 relativehumidity for 24 hours before initial color measurements

For the natural tooth group a total of 56 human centralincisors recently extracted for periodontal reasons wereselected (use of natural teeth required ethics approval votenumber 201557)The teethwere stored in a 01 thymol solu-tion at room temperature for up to 4 weeks after extractionTeeth with any visible caries cracks or hypoplastic defectswere excluded All teeth were gently polished by one clinicianwith a rubber cup and polishing paste (CleanPolish Kerr)under running water for twominutesThe crowns of the teethwere then sectioned 2 mm apically to the cementoenameljunction using double-faced diamond discs under runningwater (KG Sorensen Barueri) The pulp tissues of the crownwere removed with hand instruments cleaned and thendivided into seven experimental procedure groups (n= 8)Before the baseline measurements were taken specimenswere immersed in artificial saliva at 37∘C for 24 hoursThe artificial saliva was prepared according to the followingformula 43 g xylitol 1 g sodium carboxymethylcellulose5 mg calcium chloride 40 mg potassium 01 g potassiumchloride phosphate 1 mg potassium thiocyanate and 100 gdeionized water

22 Color Measurement The Commission Internationale delrsquoEclairage (CIE) color measurements were obtained with acolorimeter (ShadeNCC Shofu) in a viewing booth underD65 standard illumination based on ISO standards (ISO7491)The colorimeter was calibrated according to the manu-facturer instructions before the experimental measurements




00


0

lowast a0

lowast b0

lowast and L1

lowast a1

lowastb1


ΔElowast00= radic( Δ1198711015840119896119871119878119871)

2 + ( Δ1198621015840119896119862119878119862)2 + ( Δ1198671015840119896119867119878119867)

2 + 119877119879( Δ1198621015840119896119862119878119862)2 ( Δ1198671015840119896119867119878119867)

2

(1)


119871 S119862 and S





00

lowast

1) were

recorded



2

lowast a2

lowast and b2


lowast


original values (L0

lowast a0

lowast and b0

lowast) (Table 2)


lowast

1-Δ11986400

lowast



1- Δblowast

2)



lowast

1 ΔE00

lowast

2 ΔL1

lowast ΔL2

lowast Δa1

lowast Δa2

lowastΔb1

lowast and Δb2


00

lowast

1 ΔE00

lowast

2 ΔL1

lowast ΔL2

lowast Δa1

lowastΔa2

lowast Δb1

lowast and Δb2


00

lowast

1ranged


lowast



00

lowast



lowast

1and ΔE

00

lowast



00

lowast


ating the ΔE00

lowast



lowast and Δb2

lowast


lowast andΔb1






(1450 ppm fluoride)




(1450 ppm fluoride)




Colgate-Palmolive



(450 ppm fluoride)









lowast

2


lowast

1


lowast

2values ranged


00

lowast

2=31)


lowast

1andΔE

00

lowast



lowast

1

plt0001 for ΔE00

lowast


00

lowast

1

plt0602 for ΔE00

lowast



00


1

lowast- Δa2



1






4 Discussion


00



00


00


00



00



2and 10 NaF gel





2






lowast


00

lowast


1






lowast





lowast


00

lowast


1







lowast

1- ΔE00

lowast

2 ΔL1lowast - ΔL2











00








5 Conclusions






Data Availability




References







































Advances in



Journal of

Chemistry















Journal of





Volume 2018









Journal of


Na

nom

ate

ria

ls







00


0

lowast a0

lowast b0

lowast and L1

lowast a1

lowastb1


ΔElowast00= radic( Δ1198711015840119896119871119878119871)

2 + ( Δ1198621015840119896119862119878119862)2 + ( Δ1198671015840119896119867119878119867)

2 + 119877119879( Δ1198621015840119896119862119878119862)2 ( Δ1198671015840119896119867119878119867)

2

(1)


119871 S119862 and S





00

lowast

1) were

recorded



2

lowast a2

lowast and b2


lowast


original values (L0

lowast a0

lowast and b0

lowast) (Table 2)


lowast

1-Δ11986400

lowast



1- Δblowast

2)



lowast

1 ΔE00

lowast

2 ΔL1

lowast ΔL2

lowast Δa1

lowast Δa2

lowastΔb1

lowast and Δb2


00

lowast

1 ΔE00

lowast

2 ΔL1

lowast ΔL2

lowast Δa1

lowastΔa2

lowast Δb1

lowast and Δb2


00

lowast

1ranged


lowast



00

lowast



lowast

1and ΔE

00

lowast



00

lowast


ating the ΔE00

lowast



lowast and Δb2

lowast


lowast andΔb1






(1450 ppm fluoride)




(1450 ppm fluoride)




Colgate-Palmolive



(450 ppm fluoride)









lowast

2


lowast

1


lowast

2values ranged


00

lowast

2=31)


lowast

1andΔE

00

lowast



lowast

1

plt0001 for ΔE00

lowast


00

lowast

1

plt0602 for ΔE00

lowast



00


1

lowast- Δa2



1






4 Discussion


00



00


00


00



00



2and 10 NaF gel





2






lowast


00

lowast


1






lowast





lowast


00

lowast


1







lowast

1- ΔE00

lowast

2 ΔL1lowast - ΔL2











00








5 Conclusions






Data Availability




References







































Advances in



Journal of

Chemistry















Journal of





Volume 2018









Journal of


Na

nom

ate

ria

ls







(1450 ppm fluoride)




(1450 ppm fluoride)




Colgate-Palmolive



(450 ppm fluoride)









lowast

2


lowast

1


lowast

2values ranged


00

lowast

2=31)


lowast

1andΔE

00

lowast



lowast

1

plt0001 for ΔE00

lowast


00

lowast

1

plt0602 for ΔE00

lowast



00


1

lowast- Δa2



1






4 Discussion


00



00


00


00



00



2and 10 NaF gel





2






lowast


00

lowast


1






lowast





lowast


00

lowast


1







lowast

1- ΔE00

lowast

2 ΔL1lowast - ΔL2











00








5 Conclusions






Data Availability




References







































Advances in



Journal of

Chemistry















Journal of





Volume 2018









Journal of


Na

nom

ate

ria

ls







lowast


00

lowast


1






lowast





lowast


00

lowast


1







lowast

1- ΔE00

lowast

2 ΔL1lowast - ΔL2











00








5 Conclusions






Data Availability




References







































Advances in



Journal of

Chemistry















Journal of





Volume 2018









Journal of


Na

nom

ate

ria

ls






00








5 Conclusions






Data Availability




References







































Advances in



Journal of

Chemistry















Journal of





Volume 2018









Journal of


Na

nom

ate

ria

ls






































Advances in



Journal of

Chemistry















Journal of





Volume 2018









Journal of


Na

nom

ate

ria

ls






Advances in



Journal of

Chemistry















Journal of





Volume 2018









Journal of


Na

nom

ate

ria

ls




Documents

The Effect of Desensitizing Toothpastes and Coffee ...downloads.hindawi.com/journals/bmri/2018/9673562.pdf · BioMedResearchInternational oxalates, glutaraldehyde,andformaldehydeastubuleplugs