Three-month assessment of safety and efficacy of two electric toothbrushes

Journal of Dentistry (2005) 33, SuppL. 1, 23-28 ~:~-~,¢=~: > ~ ~-'~r~~1 ~

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Three-month assessment of safety and efficacy of two electric toothbrushes M.J. Cronin a, W.Z. Dembling a, M.A. Cugini b, M.C. Thompson b, P.R. Warren b,* anew Institutional Service Company, Inc., 555 Tilton Road, Northfield, NJ, USA bOral-B Laboratories, a division of The Gillette Company, Prudential Tower, 800 Boylston Street, Boston, /HA, USA

KEYWORDS EtecLnc LooLhbrush, Ptaque removal G1n81v1L1s: Gmo=wa[ bleeding, SafeLy

Summary Objective. This random]sed, exam]ner-bhnd parallel group study was designed to evaluate the safety and efficacy of a rechargeab[e oscillating/pulsating toothbrush (Ora[-B Profess]ona[Care TM 7000, Ora[-B Laboratories; PC 7000) and a battery-operated toothbrush (Crest ® Sp]nBrush TM Pro, Procter & Gamble Company; SBP) in the reduction of gingivitis, bleeding and plaque over a 3-month period. Methods. After 12-18 hours of no oral hygiene, subjects had oral tissue examinations, and g]ng]va[ and plaque assessments to determine ehg]b]hty in the study. Subjects were stratified and random]sed into t r e a t m e n t groups based on initial whole mouth mean plaque (Turesky modification of Qu]g[ey Hem Plaque Index) and gingivitis (Loe & S][ness G]ng]va[ Index) scores and gender. Subjects were instructed to brush twice daffy with their assigned toothpaste and toothbrush. Chmca[ parameters were assessed at base[me, and after 1 and 3 months of use. Within t r e a t m e n t comparisons from base[me were analysed using t-test; between t r e a t m e n t comparisons were analysed using ANOVA. Results. Data were obtained from 92 subjects (PC 7000 n=45; SBP n=47). No s]gmficant differences were found in base[me plaque, gingivitis and bleeding between groups. Both t r e a t m e n t groups had s]gmficant reductions from base[me in plaque, gingivitis and bleeding scores. PC 7000 demonstrated s]gmficant[y greater reductions compared to SBP in whole mouth plaque at 1 month: 0.39±0.43 vs. 0.16±0.42 and 3 months: 0.32±0.48 vs. 0.04±0.41. PC 7000 also demonstrated s]gmficant reductions compared to SBP in gingivitis at 3 months for whole mouth: 0.14±0.09 vs. 0.10±0.10 and approx]ma[ areas: 0.11±0.08 vs. 0.08±0.09. There were no s]gmficant differences between toothbrushes in bleeding at either time point. Safety examinations revealed no apparent difference in soft and hard tissue abnormaht]es between groups. Conclusion. The PC 7000 toothbrush demonstrated s]gmficant[y greater reductions in plaque and gingivitis compared to the SPB over a 3-month period. © 2005 Elsevier Ltd. A[[ rights reserved.

Introduction Early electric toothbrushes featuring brush heads with back and forth or side to side movement and a design

* Correspondence: P R Warren, Ora[-B Laboratones, Prudent]a[ Tower, 800 Boy[ston Street, Boston, MA, USA Te[ 617 463-9658, fax 617 4639578 E-marl address: PauLWarren®g][[ette com

based on a conventional manual toothbrush often failed to show any c[lnlca[ advantages over their manual counterparts 1. Even modern electric toothbrushes with their wide variation in brush head design and action do not necessarily have superior plaque removal efficacy to manual toothbrushes and the]r re[atwe efficacy may vary considerably from mode[ to model 2,3. As novel devices are introduced it is important that c[lnlca[ development programmes include eva[uat]on of the]r

0300-5712/S - see front matter © 2005 ELsevier Ltd. ALL rights reserved.

24 comparatwe efficacy with manual and other estabhshed electric toothbrushes so dental professionals are aware of the latest technological advances and most effectwe brushes available. Plaque missed by toothbrush]n8 follows a predictable pattern. After brushing, hngua[ surfaces tend to have more plaque than facial surfaces, molars have more remmmn8 plaque than premolars or incisors, and plaque retention is greatest on approx]ma[ surfaces 4,s. The Ora[-B range of rechargeab[e electric toothbrushes employs a circular, oscillating/rotating brush head which has proven to be more effectwe than a manual toothbrush in plaque removal from a[[ tooth surfaces, because they can reach deeper between the teeth and below the 8umhne 6,7. Advancements in technology to improve mterdenta[ penetration and enhance plaque removal have led to the addition of a high-frequency putsat]n8 action, thereby providing three-d]mens]ona[ motion in the Ora[-B Profess]ona[Care TM Series, namely the Ora[-B 3D Plaque Remover and 3D Excel models 8,9 and the most recent Profess]ona[Care 7000 (PC 7000) mode[ (Ora[-B Laboratories, Boston,/VIA, USA). Atthough toothbrush]ng is pnmanty aimed at removing and contro[hn8 plaque, the mare objectwe in the longterm is to control gingivitis and maintain good 8]ng]va[ condition. Consequently, in addition to plaque removal efficacy, chmca[ assessment of any novel device should include investigation of their influence on 8]ng]va[ health. The objectwe of the present study was to evaluate the long-term safety and efficacy of the PC 7000 compared with a battery-operated toothbrush, the Crest® SpmBrushTM Pro (SBP, Procter & Gamble Company, Cincinnati, OH, USA), ~° with particular regard to their comparatwe effect on plaque control and gingivitis.

Materials and Methods

Study population Subjects were recruited from the genera[ population in response to an advertisement. Ehg]b[e participants were non-smokers aged 18-70 years, had good genera[ health, and a minimum of 18 scorab[e t e e t h (not Including 3rd molars, teeth with orthodontic apphances, bridges, crowns or implants). In addition, subjects had to be current manual toothbrush users and have a whole mouth Loe & S][ness G]ng]va[ Index (LSGI) 11 score of />1.1 and a whole mouth Turesky e t a [ . modified Qu]8[ey Hem Plaque Index (TQHPI)12,13 score/>1.75. A[[ subjects had to refrain from a[[ other hygiene procedures for the duration of the study, such as the use of mterdentat cteamn8 products, chewing gums and mouth nnses. Subjects were excluded if they presented with any physical hm]tat]on or restriction that might preclude normal oral hygiene procedures, evidence of poor oral hygiene (e.g. severe periodontal disease or rampant canes) or major hard or soft tissue lesions at the basehne examination, or reported use of antibiotics or antHnflammatory medications for 3 consecutwe days or more within the previous 28 days, or had any medical condition with a requirement of prophylactic antibiotics before dental

M.J. Croton et at. t r e a t m e n t . Dental professionals and dental students were prohibited from participating in the study. The protocol was approved by an independent Institutional Review Board before initiation and a[[ subjects gave signed informed consent before study entry.

Study

design

The study had a random]sed, exammer-bhnd, parallel group design and was conducted over a 3-month period. At a screemn8 visit (basehne assessment), subjects who had refrained from a[[ hygiene procedures in the precedIng 12-18 hours were examined in order to estabhsh if they met the inclusion criteria with regard to oral soft and hard tissue status and pre-existing levels of plaque and 8]ng]v]t]s. Quahfied subjects were randomly assigned to one of two t r e a t m e n t groups with stratification based on initial plaque (1.75-2.5; 2.51-3.0; >3.0), 8]ng]v]t]s mean scores (1.1-1.2; 1.21-1.3; >1.3) and gender. Subjects were instructed to use their assigned toothbrush, either the PC 7000 toothbrush or the SBP toothbrush, in accordance with instructions provided by the manufacturer and the brushing techmque was demonstrated on mouth models. A[[ subjects were provided with a commercially available fluoride dent]f n c e (Colgate ® Cavity Protection Toothpaste, Co[8atePa[mohve Company, New York, NY, USA) and brushed twice daffy at home. The dates and times of brushing and use of any medication were recorded by subjects on diary forms. After 30 (±3) days, subjects returned for an interim examination, having refrained from oral hygiene for the previous 12-18 hours. Oral soft and hard tissues were examined, any adverse events were recorded, and plaque and 8]ng]v]t]s levels were assessed. Brushing instructions were reviewed with the subjects and any concerns or questions were addressed. A final examination was performed at 90 (±5) days in subjects having abstained from a[[ oral hygiene procedures in the preceding 12-18 hours.

Clinical assessments At[ chmca[ evatuat]ons were performed by the same examiner who was bhnd to the test products and treatment group assignments. Safety assessments of ora[ soft and hard tissues were performed to ]nctude hps, tongue, 8]ng]vae, subhngua[ area, inner surfaces of cheeks, mucobucca[ fords, hard and soft patate, and pharyngea[ area. Any abnorma[ findings and at[ adverse events reported were recorded. Plaque was evaluated after d]sctos]n 8 the teeth with Red-Cote ® (John O. Butter Co., Chicago, IL, USA) to stain for presence of ptaque. Subjects nnsed with 7.5m[ d]sctos]n 8 sotut]on for 10 seconds and then nnsed twice with 10mr water for 10 seconds. Plaque was evaluated us]n8 the TQHPI (0 = no ptaque/debns, 1 =separate flecks of ptaque at the cerv]ca[ margin of the tooth, 2 = a thin continuous band of ptaque [up to 1 ram] at the cerv]ca[ margin of the tooth, 3=a band of ptaque wider than 1 mm but covenn 8 tess than 1/3 of the crown of the tooth, 4= ptaque covenn 8 at [east 1/3 but tess than 2/3 of the crown of the tooth,

Three-month assessment of safety and efficacy of two eLectnc toothbrushes

5 = plaque covering 213 or more of tooth crown) on the mesla[, distal and mid surfaces on bucca[ and hngua[ areas. Gingivitis was evaluated using the LSGI (score 0-3; O= no inflammation, 3 =severe inflammation, ulceration, tendency to spontaneous bleeding) on or adjacent to meslofacla[, mldfacla[, dlstofacla[, meslohngua[, mldhngua[ and dlstohngua[ surfaces of aLL natural t e e t h in the upper and Lower jaw, giving a t o t a l of 168 possible sites. BLeeding scores (LS) for each surface w e r e derived from the LSGI w h e r e values of 2 or 3 w e r e taken as bleeding sites as described by the index.

25

Results Study groups Of 108 enrolled subJects, 92 provided eva[uab[e data (6 subjects discontinued the study for reasons such as personaL, scheduhng conflicts; 10 subjects were excluded due to protocol deviations due to medical conditions a n d / o r antibiotic use not related to product use). There were no statistically significant differences between t r e a t m e n t groups in gender or age, or in base[me plaque and gingivitis scores indicating the t r e a t m e n t groups were we[[ balanced at base[me (Table 1).

Statistical analysis A sampte size of 50 subjects per group was estimated for this study based on a previous study of a Slmltar design 6. Data anatyses w e r e performed by an independent statlstlca[ consuttant who was bhnd to the i d e n t i t y of the test products. Whore mouth ptaque, gingivitis and breeding, and safety w e r e primary endpolnts; ptaque, gingivitis and breeding at approxlma[ (mesla[ and dlsta[ combined) sites and at[ bucca[ and hngua[ surfaces w e r e secondary endpoints. Basehne distributions between t r e a t m e n t groups w e r e compared for age, and glnglva[ and ptaque scores using an anatysls of variance (ANOVA) and for gender using a chl-square test. Ptaque, gingivitis and breeding scores for whore mouth and approxlma[ sites, and at[ hngua[ and bucca[ surfaces, w e r e expressed as means and standard deviations (SD). Within each t r e a t m e n t group, the change from basehne was analysed using a paired t-test. The mean changes from basehne to Month 1 and Month 3 in the t w o groups w e r e compared using an ANOVA w i t h modets appropriate for the paratte[ group design. The Month 1 and Month 3 data were anatysed separatety using ANOVA modets t h a t lnctuded a factor for t r e a t m e n t group onty. At[ hypothesis tests w e r e conducted at the two-sided a = 0.05 [eve[ of significance. No adjustments w e r e made to P-vatues for muttlpte comparisons.

Table I SubJect demographlcs and mean whole mouLh plaque and o~mgwiDsLeveLsaL basehne

Gender ma[e/fema[e Age(yrs), mean SD Who[emouthTQHPl, mean SD Who[emouth LSGI, mean SD WhoLe mouth b[eedlno=. mean SD

PC 7000 (n 45)

SBP (n 47)

P va[Lle

13132 382 11 1 2 57 042 1.14 0.07 0 14 0 07

11/36 37 3 8.3 2 55 035 1.15 0.07 0 15 0 07

0.4695 0.6557 07586 0 5212 0 4450

Plaque control Changes from basehne in mean TQHPI scores for whole mouth and approxlmat areas, and buccat and hnguat surfaces, were analysed within t r e a t m e n t groups. Significant reductions in whole mouth and approxlmat plaque scores, and for buccat and hnguat surfaces, were found in the PC 7000 group at both 1 month and 3 months, but only at 1 month, and only for whole mouth and approxlmat areas and for hnguat surfaces, in the SBP group (Tabte 2).

Table 2. TQHPI scores and change from baseline at t month and 3 months: meaniSD Base[ine

I Month Score

Who[emouLh

PC 7000 SBP

2 57 042 2.55 0.35

2 19 0 52 2 39 0 49

Approxlma[

PC 7000 SBP

276 042 273 0 38

2 38 0 53 2 58 0 52

Bucca[

PC 7000 SBP

2.66 0.59 2 68 0 51

2.29 0 66 2 53 0 66

Lingual

PC 7000 SBP

248 043 2.42 0.45

207 0 58 2 25 0 52

Change from basehne ~ 039 042 0.16 0.42 P 00097 0 38 041 0 15 042 P 0009 0.37 0.54 0 15 0 56 P 00594, NS 041 044 0.17 0.43 P 0 0079

3 MonLhs Score 2 25 0 63 2 51 0 47 247 0 64 270 046 2 38 0 79 2 63 0 61 2 13 0 62 240 0 51

Chano~etrom basehne" 0 32 048 004 0 41 P 00033 029 049 002 041 P 00053 0 28 0 61 006 0 58 P 00721. NS 0 36 049 002 047 P 0 001

"Significant reductions from basehne in mean scores for PC 7000 group aL 1 month (aLLsites, P 0 0001 ) and 3 months (P 0 0001 for whole mouth and [lnO~Lla[: P 0.0003 for approxlma[, P 0 0034 for bucca[), significant reductions from baseline in mean scores for SBP aL 1 month for whole mouth (P 0.0139), approxlma[ (P 0 0202) and [lnO~Lla[(P 0 0106), non-significant change from baseline in mean score for SBP aL 1 month for bucca[ (P 0 0740) and aLL siLos aL 3 months (P -,0 1) [paired L-Lest] BeLween-o~roupcomparison [ANOVA], NS, non-significant

26

M.J. Croton et aL

Table 3

LSGI scores and change from baseUne at 1 month and 3 months: mean±SD Basehne

Whole moLJLh

1 MonLh Score

Change from basehne*

3 MonLhs Score

Change from basehne ~

PC 7000

1.14 0.07

1 03 0 10

0 11 0 10

I 00 0 12

0 14 0 09

SBP

1 15 0 0 7

104 0 1 2

011

105 0 1 2

010

010

P NS Approx~ma[

PC7000

1 17 0 0 9

1 09 0 0 9

008

009

1 06 0 10

0 11 0 0 8

SBP

1.19 0.08

1 11 011

008

009

1 11 011

0.08 0.09

P Buccat

NS

P 0 0369

PC7000

1 10 0 0 7

099

011

010

011

0.93 0 1 4

0.17 0.12

SBP

1 11 0 0 8

098

014

013

013

098

013

PC7000

1 19 0 1 0

107 0 1 2

012

011

107 0 1 3

012

009

SBP

120

1 11 0 1 3

009

012

1 12 0 1 3

008

009

015

P NS L~no~ua[

010

P 00416

010

013

P NS

P NS

P NS

~S1gnlflcanL reducL1ons from basehne in mean scores for boLh ~roups at a[[ siLes aL boLh I monLh and 3 months (P 0 0001 ) [palred L-LesL]

BeLween-group comparison [ANOVA]:NS, non-slgmflcanL

[F-'JPC7000 i-1SBP I

Ii']PC 7000 FISBP I

• 14

::

~ 14

e

::

~e

12 10

: ::

12 ~ 10 8 0

1-month F]gure

3-monks

Percentage reducUon from baseLine m TQHPI scores a t 1 m o n t h and 3 months

A comparison of mean plaque reductions between t r e a t m e n t groups s h o w e d t h a t t h e PC 7000 t o o t h b r u s h was s ] g m f i c a n t [ y m o r e e f f e c t i v e in p l a q u e c o n t r o l ( w h o l e m o u t h , and a p p r o x l m a [ areas and hngua[ surfaces) t h a n t h e SBP at b o t h 1 m o n t h and 3 m o n t h s (TabLe 2 and Fig• 1)•

l-month

IDPC 7000 D s B P I ~ 5o 4o

~ 2o e~

Gingival condition Both t r e a t m e n t groups demonstrated a slgmficant decrease m mean LSGI scores after 1 month and 3 months of product use, with reductions from basehne being progresswe over the study duration m the PC 7000 group (TabLe 3). The reduction in mean LSGI scores was slgmficantLy greater m the PC 7000 group than the SBP group at 3 months at both whole mouth and approxlmaL surfaces• Mean whole mouth LSGI scores were reduced by 13% m the PC 7000 group versus 9% in the SBP group, whLe mean approxlmaL LSGI scores were reduced by 10% m the PC 7000 group versus 6% in the SBP group (Fig. 2). Mean LS bleeding scores were slgmficantLy reduced at 1 month and 3 months in both t r e a t m e n t groups, but no slgmficant difference was found between groups (TabLe 4 and Fig. 3).

3-mont/as

Figure 2 Percentage reduction from base[me in LSGI scores at 1 month and 3 months

o

l-month

F]gure

3-months

Percentage reducUon from basebne ]n LS bleeding scores at 1 month and 3 months

safety Both t o o t h b r u s h e s w e r e f o u n d t o be safe o v e r 3 m o n t h s o f p r o d u c t use. O b s e r v a t i o n s o f o r a l hard and soft tissue s h o w e d o n l y rare a b n o r m a l i t i e s : at baseline, 3 s u b j e c t s m t h e PC 7000 g r o u p s h o w e d a b n o r m a l i t i e s (to hard tissue) and 2 subjects in t h e SBP g r o u p had a b n o r m a l i t i e s (to g m g w a e and Lips); a t 1 m o n t h t h e r e w e r e r e p o r t s o f a b n o r m a l i t i e s t o t h e g m g w a e (1 s u b j e c t ) , Lips and hard tissue (2 subjects each) in t h e PC 7000 group and t o t h e

Three-month assessment of safely and efficacy of two eLecLnc toothbrushes Table 4

27

LS bLeedln8 scores and change from basebne aL 1 month and 3 months: mean±SD Basebne

Who[emouLh

PC 7000 SBP

1 Month Score

Chan~e from basebne*

3 Months Score

Chano~efrom basebne"

0.14 0.07

009 006

005 007

007 006

007 005

0 15 0 0 7

0 11 0 0 8

004

0 11 0 0 8

004

006

P NS

007

P NS

Approx~ma[

PC 7000 SBP

0 17 009 0.18 0.08

0 11 008 0 13 0 10

006 008 006 008

009 007 0 13 0 10

Buccat

PC 7000 SBP

0 10 007 0 11 008

007 006 007 007

003 008 003 007

Llno~ua[

PC7000 SBP

018 010 0 20 0 10

011 009 0 14 0 11

008 008

010 010

008 008

0 05 0 10

0 14 0 10

0 05 0 08

P NS

P NS 0.05 006 007 008

P NS

P NS

008 006 0.05 0.09 0.05 0.06 004 008 P NS

P NS

~SloomficanLreducLlons from basebne ~n mean scores for PC 7000 o~roupaL 1 monLh (P 0 0001 for who[e mouLh, approx~ma[, bno~ua[, P 0 0274 for bucca[I and 3 monLhs (P 0 0001 for a[[ sites), s~omficanL reducL~onsfrom base[me in mean scores for SBP aL 1 month for who[e mouth and approx~ma[ (P 0 0001 ). bucca[ (P 0 0014) and bno~ua[(P 0 0003). and aL 3 months for who[e mouth, approx~ma[ and bngua[ (P 0 00011 and bucca[ (P 0 00341 [prated L-Lest] BeLween-o~roup comparison [ANOVA]. NS. non-s~o~mficanL. gmgwae (2 subjects) and hard and soft palate (1 subject) m the SBP group; and at 3 months to the gmg~vae and hard t~ssue (1 subject each) m the PC 7000 group and to the gmgwae (4 subjects) and mucobucca[ folds (1 subject) m the SBP group. Fifty subjects (25 per group) expenenced adverse events, mostly of a medical nature 1.e. cows, fevers, nausea, muscle aches etc., and m~td to moderate m seventy. The study was hew dunng w i n t e r months so these were not unexpected events. Four adverse events (2 per group) were regarded as defimtety or possibly product related, were of m~td seventy, and were recorded as gmgwa[ ~mtat~on. At[ adverse events resolved w i t h o u t the need for further treatment.

Discussion Faced with an array of electric toothbrushes featunng different brush head designs and modes of actions, dental professionals rely strongly on cbmcat ewdence as to w h c h one is the most effective in controtbng plaque and lmprowng gmgwa[ health. IncreasingLy, comparatwe cbmca[ studies indicate some electric toothbrushes have greater potential to remove plaque and enhance gmglvat condition than others 3,14~6. The two electric toothbrushes used m the present study have entirely distract modes of operation and brush head designs, and as a consequence may vary in efficacy. The novel Orat-B rechargeabte PC 7000 toothbrush incorporates a smart brush head with a puLsating/osciLLating/rotating action, white the SBP has a target brush head with an osciLLating and translating back and forth action. ResuLts from this 3-month comparative study demonstrate that the PC 7000 and SBP toothbrushes differ considerably in their ability to control whole mouth plaque and improve g]ng]va[ health. PLaque control for the whole mouth (and approx]ma[ sites and Lingua[

surfaces) at 1 month and 3 months was slgmficantty greater with the PC 7000 toothbrush than the SBR Improvements m gmgwa[ health (as measured by LSGI) were also slgmficantty greater for the whole mouth (and approxlmat sites) at 3 months with the novel PC 7000. BLeeding was slgmficantty reduced m both study groups, but differences between groups did not reach statistical slgmficance. The tack of a slgmficant group difference may reflect the tow LS values at baseline due to the derivation of these values from LSGI scores of 2 or greater. A singLe-use plaque assessment of the PC 7000 and SBP brushes found slgmficantty greater plaque removal efficacy with the PC 7000 brush for the whole mouth as wet[ as for approxlma[ surfaces 17. SingLe-use plaque assessments provide a useful indication of the plaque removal ability of a toothbrush, but studies of Longer duration are required to assess plaque control and any effects on glnglvat condition. Consldenng the strong bnk between plaque accumulation and development of gingivitis, it might be expected that enhanced plaque removal in short-term use 18 might translate into enhanced plaque control and improved gmgwa[ health m the longer term, as was found to be the case in the present study. ALthough it is difficult to recreate normal home use dunng a cbmcat investigation, the methodology attempted to ensure that study findings reflected the cteamng performance of the two etectnc toothbrushes when used as part of a twice-dalLy oral hygiene routine. FirstLy, subjects were recruited from the general population and were current manual toothbrush users, and secondly, the test products were used according to instructions prowded by the manufacturer and compbance was assessed by means of a diary form. Despite these considerations, the change from basebne plaque index at 1 month was greater than that at

2_8

3 months for both toothbrushes, whlch may show that subject motwatlon was helghtened dunng the first part of the study, a phenomenon known as the 'Hawthorne effect't9. Nevertheless glnglvai condltlon, as determlned by both glnglwtls and bieedlng indlces, was improved conslstentiy at whole mouth and approxlmai sltes over the 3-month study duratlon wlth the PC 7000 toothbrush, but not wlth the SBP. Conclusion This 3-month comparatwe study found that the OraL-B Profess]onaLCare 7000 rechargeabLe powered toothbrush is significantly more effectwe at controihng plaque and improving g]ng]va[ health than the Sp]nBrush Pro batteryoperated toothbrush. The advantage in favour of the Profess]onaLCare 7000 was evident for the whole mouth and more difficuLt-to-reach approx]ma[ surfaces. Both products were safe to hard and soft oral tissues over the 3-month study period.

Acknowledsements The authors would hke to thank MeLynda HazeLwood, STATKING ConsuLting, FairfieLd, OH, USA for statistical analysis and Dr Jane MitcheLL, MWS, Staffordshlre, UK for preparation of this manuscript. References I

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M.J. Croton et at.

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