Periodontics

Comparison between manual and mechanicalmethods of interproximal hygiene

Petra Schmage, DMD, PhDVUrsula Platzer, DMD, PhD'Vlbrahim Nergiz, DMD, PhD'

Objective: The aim of this study was to compare the effectiveness of the automated tnterctean tnterdentaiPlaque Remover with that of interdental brushes and Ultrafloss. Method and materials: The interdentalhygiene effectiveness of 35 healthy patients suffering from gingivitis was studied by an examiner daily overa period of 1 week. The sizes of the interdental spaces were classified and corresponding-sized interden-tal brushes or floss was selected. In a random, split-mouth design both interdental cleaning methods, me-chanical and manual, were applied while the patients continued to use standard brushing techniques.Disclosed proximai plague, the papillary bleeding index, and interdental bleeding tendency on stimulationwere evaluated. Results: The papillary bleeding index was reduced from an average value of 40% to 25%.Only 5% of interproximal plaque remained añer manual interdental cleaning, whereas 40% of plaque wasstill present añer use ot the ¡nterclean device. Cleaning efficiency of manual and mechanical methods wascomparable in only 1 interproximal space size. At the end of the study, the interdental bleeding on stimula-tion was significantly higher in the automatically cleaned interspaces than in the manually cleaned spaces.Conclusion: f\Aanua! interproximal cleaning was more effective than the automated device. (QuintessenoeInt 1999:30:535-539)

Key words: dental fioss, interciean, interdental brush, interproximai cieaning, papillary bleeding index,plaque

CLINICAL RELEVANCE: When selected to fit in individ-ual interproximai space sizes, manual Interproximalcleaning devices were extremely etfective.

The relationship between the daily removal of bac-terial plaque and inflammatory periodontal dis-

ease has heen proven,' It is well known that the great-est occurrence of gingivitis and/or periodontitis hasbeen found interproximally. Because toothbrushingalone is not able to reach tbe interdental region effi-ciently, other cleaning aids also have to he used,̂ '̂Several interdental cleaning devices are available, in-

•Assislant Prolessor, Deparlmenl of Operative Dentistry and Pen-oûantology. Dental School, Unii/ersity of Hamburg, Hamburg, Germany

"Professor and Chairperson, Department of Operatiue Dentistry and Peri-odonlology, Denial School, University of Hamburg, Hamburg, Germany.

Reprinl requests: Dr Petra Sclimage, Deparlmenl of Operative Dentistryand Periodontology, Dental Sohool, University of Hamburg, Marliristrasse52, Í0 246 Hamburg, Geimany Fax: 49-40-47t7-516e

eluding dental floss and/or interdental hrushes. Theeffectiveness of these devices depends on their con-formity to the shape and size of the interdental spaceas weil as on the morphoiogy of the proximai toothsurface,''"*

In general, individuai motivation and handlingskills are the most important criteria for maintainingthe reliability of all interdental devices in the longterm,' Accordingly, it is an advantage to primarily ex-clude these subjeetive factors during ciinicai examina-tion of the effectiveness of interdental devices. Theeffects regarding the patient's skills should be consid-ered in a second step, eg, if patients are ahle to cleanall their interspaces using interdental devices. Surveyshave shown that few people follow usage recommen-dations,**'* The patient's compliance could he improvedby cleansing methods that are time saving, easy to use,and pleasant to handle.

Recently, a new automated device has been intro-duced (Interciean Interdental Plaque Remover,Braun/Oral-B). The main advantage of this product-the easier handling-is expected to lead to a better useracceptance. The aitn of this in vivo study was to com-pare the effectiveness of the Interciean InterdentalPiaque Remover with that of manual interproximalcleaning devices.

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Fig 1 Seven groups of interproximai space sizes were ciassiliedcorresponding lo fioss or interdental brushes' (1) Uitrafloss: (2)Curaprox CPS 007; (3) TePe Red (diameter: 0 5 mm), (4) TePeBlue (diameter' 0.6 mm); (5) TePe Yeliow 0.7 mm); (6) TePe Green(diameler: 0 8 mm¡; Í7J TePe Violet (diameter; 1.1 mm).

Fig 2 (right¡J\p ol Ihe interoiean interdentai Piaque Remover.

METHOD AND MATERIALS

Thirty-five adult patients suffering from gingivitiswere studied (20 women and 15 men). They had an av-erage age of about 32 years (median: 25"/b/75% = 27/45years). The patients fulfilled the following criteria: Theywere in a good state of health, were taking no antico-agulants, had received no medications during the last 6months, had no periodontal treatment needs, had nocarious lesions or insufficient restorations, and had atleast 20 teeth forming interdental spaces.

The patients who visited the chnic for a control ex-amination, which included calculus removal, wereasked if they would participate in this study. The base-line examination (day 0) occurred on a Monday, about2 weeks later, and the chnical trial started the follow-ing Monday (day 7).'°

The individual sizes of the interdental spaces wereclassified with a scaled, tapered Curaprox IAP(Interdental Access Probe; Curaden). Correspondingto the length of the IAP, 7 groups of interdental clean-ing devices were selected: Uitrafloss (Oral-B),Curaprox CPS 007 (Curaden), and TePe, 5 sizes ofwhich are availahle (Fig 1). The Curaprox CPS 007has the smallest feasible size.

The baseline interdental bleeding tendency (IBT)was measured on day 0, and each interdental space wascleaned with the individually selected device. Bleedingon probing was scored as a "yes" or "no" decision. Thismethod modified the interdental bleeding indexes used^by Caton and Poison" as well as Carter and Barnes.'^

The primary interdental cleaning procedure was neces-sary to evaluate the IBT but was not part of the trial.

During the following week (days 1 to 6), there wereno investigations, but the patients had to continuetheir conventional oral hygiene, excluding any influ-ence of the baseline treatment on the research. Oneday prior to tbe beginning of tbe study {day 6,Sunday}, the patients were requested to interrupt theirinterdental hygiene for the next 6 days and to use onlythe standard brushing technique without use of flossor interdental brushes.

Only 1 dentist carried out the investigation. Eachpatient was examined by the same dentist every dayover a 5-day testing period from day 7 (Monday) untilday 11 (Friday). The same examiner performed the in-terdental hygiene measures for the participants undersurgical conditions once a day (days 7 to 11). Fromthe start of the trial period (day 7), the evaluation wasbegun each day with staining of the plaque with aplaque-diselosing solution (Mira-2-tone, Hager &Werken). Plaque older than 24 hours was colored vio-let and plaque younger than 24 hours pink. On days 7and 11, the interproximal plaque index (IPl) was mea-sured prior to cleaning iDy counting the number ofproximal spaces showing disclosed plaque,''•'''

The Interclean Tower ID 20/25 consists of a fast-rotating filament (6,500 rpm) made of the elastomer-plastic, hytrel. The diameter, 0.3 mm, is equal to that ofaverage dental floss (Fig 2). During rotation, the fila-ment is pushed out of a bent tube and then makes afunnel-shaped movement. Tbe filament rotates around

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PapillaIV bleeding mije

Inte relean Manua

Fig 3 interproximal piaque and bleeding scofes on days 7 and 11oí the investigation. Statisticaily signilicant difterences are indicated.NS = No(signiticant{P> 0.05): "P< 0.05, ••P< 0 01; " *P< 0 001.

Before AfterManual

Fig 4 Interdental bleeding tendency al baseline ¡befcre) and atthe end ot the test period (after), by tootti position.

a fixed point at the end of the tube. Because it is bentwhile rotating, it deflects to a wider radius at its end.When the tip of the device is positioned in the inter-proximal space during use, the filament passes throughthe interspace, below the eontact point. The filament isexpected to reach the surrounding tooth surfaces andremove the adhering plaque during rotation.

Two interdental cleaning methods were randomlyapplied in a split-mouth design,'' '" !n half of thetnouth, the tip of the Interclean device was positionedbuccally or labially to each interdental space andturned on for 4 seconds. Because the cleaning proce-dure was performed under standardized conditions,the correct handling could be eontroUed. Positioningof the filament occurred at an optimum angle, and theend could be viewed orally. In accordance with therecommendations of the manufacturer, a new tip wasused every day. In 7 patients, some filaments were bro-ken because interproximal spaces were very narrow.

The interdental spaces of the other half of the mouthwere cleaned with individually selected manual inter-dental brushes, used in baeliward and forward motions5 times, Ultrafloss was applied with up and down mo-tions on the surfaces of both approximating teeth.

The eleaning effectiveness was noted by countingthe interdental spaces that still beld disclosed plaque,without differentiating between iocation (ie, marginal,buccal, or lingual aspect). The papillary bleeding index(PBI) was evaluated, as described by Saxcr andMiJhIemann, on days 7 and 11 of the study after inter-dental cleaning,'^" On the last day of the study (day11}, interdental spaces that had been cleaned with theInterclean device during the trial were additionallytreated with the same manual devices that had been in-

dividually determined (for size) at baseline. The IBTwas noted at both sides of the mouth after cieaningwith the individually selected manual devices. The pa-tient's opinion of the Interclean device was noted aspart of the study.

All obtained data were analyzed with the statisticalprogram SPSS/PC-i- (version 7,0) (SPSS). The resultswere statisticaliy calculated by the iVlann-Whitney Utest and the Bonferroni method, as well as the para-metric t test for correlations.

RESULTS

At the beginning of the investigation, the interdentalplaque index and the papillary bleeding index scoresdernonstrated an equal distribution according to thesplit-mouth design, thus allowing comparison (Fig 3).Both indexes decreased significantly toward the end ofthe investigation. The difference in the iPI after the useof either cleaning method was not statisfically sigtiifí-cant. The PBI decreased from an average value of 40%to 25''/o, showing a larger decrease in association withmanual de\'iees. At the end of the study, a significant dif-ference (P < 0,05) between cleaning methods was found.

Only 5% of the interproximal plaque remained aftermanual interdental cleaning, whereas 42% of the plaquewas found after use of the Interciean device. There wereno signifieant differences in the removal of the disclosedplaque depending on the position of the interproximalspaces. The average interdental bleeding tendencyproved to be about 85% for anterior and posterior teethbefore the tesfing period started and decreased signifi-cantly with both methods (Fig 4), At the end of the

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Half of Ihe mouthlo be cleaned by;• Interclean

1 • Manual devices

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I1111•

r^ •Im1 2 3 4 5 6 7

S ze of interproximai space

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^ 50

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^ 1 3_ ^ Size ofS f- interproximai1—1 £. space

A il•TTL Mhi. rBlK

AnlcNor teeth Premolars Molars

Fig 5 Frequency of various SJzes of interdental spaces, as clas-sified at baseline.

Fig 6 Relationship between fhe size of the interproximai spaceand the position of the tooth.

90

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2 3 4 5 6 7Size ol inlerprox mal space

Fig 7 Probability tfiat the Interclean device will achieve the samelevel ot cleaning effioiency as manual devices, as a iunction of thesize of the interdental spaoe.

study, the IBT of the interdental spaces treated byInterclean was significantly higher than that of thosecleaned manually. Within each group, a higher fBT wasfound near the molars than at the anterior teeth.

Figure 5 displays the frequency of the occurrence ofspecific interdental space sizes, which were classifiedduring baseline treatment. Both trial groups were ho-mogeneously divided and therefore comparable. Therelationships hetween the interdental space sizes andthe positions of the teeth are presented in Fig 6. Mostinterproximai spaces at anterior teeth were sized forthe use of floss. For premolars and molars, the graphsshow peaks at the space sizes 2, 3, and 4.

Correlation of the previous data revealed that, at asize 5, the same levei of cleaning can be achieved witheither the fnterclean device or a manual device (Fig 7).

The patients reported their feelings about the ciean-ing but had no handling experience. They noted lesscleaning effect when the Interclean device was usedthan when interdental brushes or floss was used. Theytherefore preferred the manual devices. Only 6 pa-tients selected the Interclean device as their prefer-ence. Ten patients stated the tnterclean device gavethem an unpleasant feeling during use.

DISCUSSION

The remarkable decrease in the IPI and the PBlwithin 1 week could be explained as the Hawthorneeffect.' This describes the exceptional motivation ofpatients while participating in a clinical study, whichin this case concerned basic oral hygiene. The IPI wasnot expected to change within the cleaning groups be-cause the situation was measured prior to cleaning.The low significant difference in the PBI values afterthe trial indicated that better oral hygiene immediatelyimproves gingival health.'"

The cleaning effectiveness evaluated in this studydid not correlate with the position of the teeth be-cause the interdental cleaning procedure was per-formed by the dentist. Accordingly, as a result of thedesign of this study, the patient's skills did not influ-ence the dental hygiene. It is well known that the suc-cess of an interdental cleaning device depends on thepatient's ability to handle it. The primary intention ofthis study, however, was to prove the objective efficacyof the tested devices. Had the cleaning effectiveness

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been proved successful, the patient's individual clean-ing skills could have been tested in a ioUow-up study.

Only a few investigations have analyzed the Inter-clean device, Cronin and Dembling'" as well as Gordonet al'̂ found it to have efficiency similar to that of man-tial dental floss, Dörfer and Schagen^" agreed using aminimum cleaning time of at least 3 seconds. Theyconfirmed, however, that manual floss provided a supe-rior cleaning efficiency when a longer cleaning timewas used. Therefore, the present study was based on acleaning time longer than 3 seconds.

Observation of the disclosed plaque after use of the'Interclean device revealed that plaque tended to re-main on the curved sides of the tooth surfaces, in andaround the interdental space, and inside the gingivalsulcus. The Interelean filament cleaned only a straightcanal through the interspace. Clinically, the cleaningeffectiveness cannot be controlled in the middle of thetiarrow interspace, although it can be simulated usinga model.'•'*-'' The effect of manual devices can be in-creased with the use of a crosswise movement. It isnot possible to use the Interclean tip in this way.

The Interclean device demonstrated an acceptableefficiency only in interproximal space size 5, whiehcorresponds to the yellow TePe brush. Because it isknown that this space size rarely occurs at all sites in1 mouth, the effectiveness of this is hypothetical.

If patients are given proper instruction, the perfor-mance of manual interproximal cleaning with inter-dental brushes and/or Ultrafloss would be expected tobe more effective tban tbe performance of the me-chanical Interclean device under tbe same conditions.The evaltiation of the interdental space size and indi-vidual instruction in hygiene are mandatory to acbiev-ing bigh effectiveness in manual cleaning.

Contrary to tbe findings of this study, other authorswho compared manual floss and Interclean did notfind manual cleaning to be superior,'*-^" However, thecleaning effectiveness of interdental brusbes is far bet-ter in the interproximal spaces wbere both floss andinterdental brusbes can be used, '̂

CONCLUSION

Manual interproximal bygiene agents provided ex-tremely high cleaning effectiveness when they were se-lected after consideration of the individual interdentalspace sizes. In comparison to an automatic device,manual devices showed superior effectiveness.

REFERENCES

1. Loe H, Theilade E, Jensen SB, Experimental gingivitis intnan, I Periodontol 1965 ;36; 177-187.

2. Graves RC, Disney JA, Stamm JW. Comparative effective-ness of flossing and brushing in reducing interproximalbleeding, I Periodontol 1989;60:243-247.

3. lileber C|, Putt MS Evaluation of a floss-holding device com-pared to hand-held Qoss for interproximal plaque, gingivitis,and patients acceptance. Clin Prev Dent 1988;10(4):6-14,

4. Bcrgenholtz A, Olsson A. Efticacy of plaque-re m ova I usinginterdental brushes and wased dental floss. Scand J DentRes 1984:92:198-203.

5. Waerhaug J, The interdental brush and its place in operativeand crown and bridge dentistry. J Oral Rehabil 1976;3:107-113.

6. Smukler H, Nager MC, Tolmie PC. Interproximal toothmorphology and its efiect on plaque removal QuintessenceInt 1989;20:249-255,

7. Stewart JE, Wulfe GR, The retention of newly-acquiredbrushing and flossing skills. | Clin Periodontol 1989;16:331-332,

8. Chen MS, Rubinson L. Preventive dental behavior in fami-lies: A national survey, J An Dent Assoc 19a2;105:43-46.

9. Craig T, Montague JL, Family oral health survey, J Am DentAssoc 1976;92:326-332,

10. Waerhaug J, Healing of the dento-epithelial junction follow-ing subgingival piaque control, | Periodontol 1978;49:l-8.

11. Caton JG. Poison AM. The interdental bleeding index: Asimplified procedure for monitoring gingival health.Compend Contin Educ Dent 1985;6:88-92,

12. Carter HG, Barnes GP. The gingival bleeding index. J Peri-odontol 1974.35,801-804.

13. Yankell SL. Green PA, Greco PM, Stoller NH, Miller MF.Test procedures and scoring criteria to evaluate toothbrusheffectiveness. Clin Prev Dent 1984;6(2):3-8,

14. O'Leary TJ, Drake RB, Naylor ]E. The plaque controlrecord, | Periodontol 1972;43;38-40,

15. Hujoel PP, Loesche WJ, Efficiency of split-mouth designs. JClin Periodontol 1990;17:722-728,

16. Saxer UP, Turconi B, Elsasser C. Patient motivation withthe papillary bleeding index J Prev Dent 1977;4:20-22.

17. lileisner |, Imfeld T, Evaluation of the efficacy of interdentalcieaning devices, ¡Clin Periodontol )993;20:7C7-713,

18. Cronin M, Dembling W. An investigation of the effieacy andsafety of a new electric interdental plaque remover for thereduction of interproximal plaque and gingivitis, | Clin Dent1996;7:74-77

19. Gordon JM, Frascella JA, Reardon RC. A clinical study ofthe safety and efficacy of a novel eieetric interdental clean-ing device, J Clin Dent 1996:7:70-73.

20. Dörfer CE, Schagen B Efficacy of a powered interdentalcleaning device compared to floss [abstract 139]. J Dent Res1998;77:123.

21. Kiger RD, Nylund K, Feller RR A comparison of proximalplaque removal using floss and interdental brushes, J ClinPeriodontal 1991;18:681-684.

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