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FINAL REPORT FOR THE STUDY ENTITLED:

"CLINICAL COMP ARISON OF

LACLEDE APF FOAM WITH NUPRO APF GEL"

Submitted To: Laclede Research Laboratories15011 Staff CourtGardena, CA 90248

Submitted By: Gary M. Whitford, Ph.D., D.M.D.Department of Oral BiologyMedical College of GeorgiaAugusta, GA 30912-1129

Date: August 31, 1993

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SUMMARY-

Fifty children were treated with two,I.23% topical APF products to determine

the weights required to provide adequate coverage of the teeth in both arches, the

weights of fluoride retained by the subjects, and the fluoride concentrations in whole

saliva and surface enamel of maxillary central incisors The products were Laclede's

Topical Fluoride Foam and Johnson & Johnson's NuPro APF Gel. The treatment time

was 4.0 minutes and an average of 16 days elapsed between the two treatments

An average of 0.89 9 of the foam product was used which contained 10.77 mg

of fluoride. An average of 3.88 9 of the gel product was used which contained 48.33

The weights of fluoride retatped (not recovered from the mouth) bymg of fluoride.

the subjects were 1.27 mg and 6.97 mg, respectively. Immediately after the APF

treatments, the average salivary fluoride concentrations were 77.4 mmol/L (1471

ppm) and 189.9 mmol/L (3608 ppm), respectively. Ten minutes later the

concentrations were 1.22 mmol/L (23 ppm) C!,nd 1.60 mmol/L (30 ppm). The

differences between the values for all of these variables were statistically significant.

The enamel was sampled in1.n1:eqi~tely before and 15 minutes after the APF

treatments using an acid-etch biopsy technique. The average control enamel fluoride

concentrations before treatment with the foam and gel products were 2935 ppm and

The post-treatment enamel fluoride concentrations were 79823123 ppm, respectively

The: diffe:re:nces between the control concentrationsppm and 7727 ppm, respectively.

and between the post-treatment concentratio~s were not statistically significant

It was concluded that the two prQducts are equivalent with respect to their

abilities to deposit fluoride on enamel. The Laclede Topical Fluoride Foam I however,

provides an advantage in that only about 200/p as much product and fluoride are used

which significantly reduces the amount of fluoride retained by the patient

3PURPOSES OF THE STUDY1

The purposes of this clinical study with child dental patients were to

compare two acidulated phosphate fluoride (APF) products with respect to the:

weights of product and fluoride required to fill full-arch maxillary and1

mandibular dental trays sufficiently to provide adequate coverage of the teeth;

2. weight of fluoride retained in the mouth after the APF treatments;

3. salivary fluoride concentrations after the APF treatments;

4. concentrations of fluoride in surface enamel after the APF treatments,

n TEST MATERIALS

The test materials were Topical Fluoride Foam@ (Lot No.921201), a

product of Laclede Research Laboratories, and NuPro@ APF Gel (Lot No

lJl156P), a product of the Johnson & Johnson Company The foam product was

The gel product wassupplied to the Principal Investigator by the manufacturer.

purchased from a dental supply company.

SUBJECTSill

Fifty healthy children, ranging in age from 8 to 12 years, participated in the

study. They were recruited from the patient population of the Department of

Pediatric Dentistry at the Medical College of Georgia (MCG), Augusta, GA.,

where the clinical procedures were done. There were 20 female and 30 male

subjects. The mean (I SE) ages of the female and male subjects were 9.95 I 0.33

years and 9.80::!: 0.27 years, respectively. Each subject and a parent or guardian

signed the informed consent form which had been approved by the MCG Human

Assurance Committee

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ACID-ETCH BIOPSY-.."'-:- ~.~C;t- fnT' each child, a maxillary central incisor wasVI.

6complete collection of any remaining acid. The NaOH rinses were added to the

same microbeaker.

The mass ofThe biopsy solution was analyzed for fluoride and calcium.

enamel biopsied was calculated based on the assumption that enamel is 37%

calcium by weight. The depth of the biopsy was calculated based on the

assumptions that the density of enamel is 2.95 and that the geometry of the

biopsiedsite was a cylinder.

VII. DETERMINAnON OF FLUORIDE APPLIED AND RETAINED

The weight of fluoride applied for each topical treatment was calculated by

multiplying the fluoride concentration of the foam or gel by the weight of foam or

gel used. After 50 ~L of the saliva and APF foam or gel mixture {collected

immediately after the 4-minute treatment) were removed for fluoride analysis, the

remaining mixture was transferred with multiple distilled water rinses to the 400

mL beaker containing the drool and stock trays. Any APF foam or gel adhering to

Thethe trays was collected in the beaker using a forceful distilled water spray

total volume was then adjusted to 400 mL with distilled water. The solution was

swirled using a spin bar and magnetic stirrer until all traces of the foam or gel

The solution was then analyzed for fluoride. The totalwere no longer visible

amount of fluoride recovered from the mouth was calculated as the product of the

The weight of fluoride retained was calculated byconcentration and volume.

CHEMICAL AND STATISTICAL ANALYSESVII.

The chemical analyses were done in a "blind" manner, i.e., the analyst was

not aware of whether the samples were associated with the use of the foam or gel

product. Fluoride was analyzed using the ion-specific electrode and a minature

7calomel reference electrode coupled to a potentiometer. Prior to analysis, all

standards and samples were buffered by the -a~dition of an appropriate volume of

TISAB. Calcium in the acid-etch biopsy solution was determined using atomic

absorption spectroscopy. The fluoride concentrations of the test products were

determined after a 1:1000 dilution with distilled water. The data are expressed as

mean:!: SE (n). The data were analyzed for statistically significant differences

using one-way factorial or repeated measures analysis of variance.

RESUL 1'5 AND COMMENTSVII,

The fluoride concentrations of the Laclede Topical Fluoride Foam and the

NuPro APF Gel were 12,047 ppm and 12,469 ppm, respectively. These

concentrations were within the required, specified range of 12,300 :t 615 ppm

The net weights of product and fluoride applied to the teeth of the subjects

are shown in Table 1. Also shown are the weights of fluoride that were retained

(not recovered from the mouth) by the subjects.

Table 1

Product Applied (g) F Retained (mg)F Applied (mg)

Laclede Foam 1.27

::!: 0.11 (44)

0.89:t 0.02 (50)

10.77:t 0.19 (50)

NuPro Gel 3.88:t 0.06 (50)

48.33:t 0.69 (50)

6.97:1: 0.73 (44)

0.00010.0001 O.OOOlp value

The weights of product and fluoride placed in the trays that were required

to provide adequate coverage of the teeth and the weight of fluoride not

recovered from the mouths of the subjects (i.e. retained by the subjects) were

significantly smaller when the foam product was used.

8Table 2 shows the fluoride concentrations of the whole saliva samples. The

"control saliva" sample was taken shortly befor.e the-first acid-etch enamel biopsy;

the "saliva/ APF" sample was taken immediately after the 4-minute APF

treatment; the "post-treatment saliva" was taken 10 minutes after the 4-minute

APF treatment.

Table 2.

Control Sali va(mmol/L)

Saliva/ APF(mmol/L}

Post-treatment Saliva(mmol/L)

1.22::t 0.12 (48)

Laclede Foam 0.0063:!: 0.0007 (50)

77.4

:t 7.7 (49)

189.9:!:13.4 (49)

1.60::!: 0.17 (48)

N uPro Gel 0.0079:t 0.0012 (50)

0.214 0.0001 0.018p value

The difference between the fluoride concentrations of the control saliva

samples was not statistically significant but the differences between the mean

values of the samples collected after the APF treatments were significant. The

fluoride concentration of the saliva/ APF sample after using the NuPro Gel was

2.5 times that observed after the use of the Laclede Foam These results are

consistent with the facts that more fluoride was introduced into the mouth with

the gel product and that more was retained subsequently. The weights of saliva

expectorated during the timed, 2.0-minute collection of saliva, which started 10

minutes after the APF treatments, were 2.73:1::0.19 and 2.83:1:-. 0.25 9 for the foam

and gel products, respectively. Therefore, the significant difference between the

fluoride concentrations of the post-treatment samples was not explained,by

differences in salivary flow.

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Table 3 shows the enamel fluoride concentrations immediately before and

15 minutes after the APF treatments and the dept~ of the acid-etched biopsy sites

Table 3.

Enamel [F]Before (ppm)

Enamel [F]After (ppm)

Depth of Etch Depth of EtchBefore (J.lIn) After (1J.m)

LacledeFoam 2935

:t 178 (50)

7982

:t 767 (50)

2.81:t: 0.13 (50)

2.39:!: 0.13 (50)

NuPro Gel 3123

:t 473 (50)

7727

I 1221 (50)

2.57:to.11 (50)

2.57.:to.11 (50)

p value 0.695 0.844 0.156 0.196

There were no statistically significant differences for the uptake of fluoride

by the enamel nor for the depth-of-etch data The average net increases in enamel

fluoride concentration for the Laclede Foam and the NuPro Gel were 5047 ppm

and 4604 ppm, respectively This difference was not statistically signficant.

The data in Table 3 indicate that the two products were equivalent in terms

of the short-term deposition of fluoride on the enamel surface. Because 25 of the

subjects were treated with the foam product first and 25 were treated with the gel

product first, it was also possible to determine whether there was a difference

between the products in terms of the enamel fluoride concentrations after

approximately two weeks. Table 4 shows the fluoride concentrations of the

control acid-etch enamel biopsies, i.e., those done prior to the application of the

APF treatments

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Table 4.

Product Used SecondProduct Used First

Laclede Foam 2744

:t 299 (25)

3127

:!: 193 (25)

N uPro Gel 3780

::!: 924 (25)

2466

:t 152 (25)

The control enamel fluoride concentrations were higher the second time for

both products which indicated that some of the fluoride deposited on the enamel

after the first topical APF treatment was still present. When the foam product

was used first, the control concentration approximately two weeks later was 3780

ppm, a net increase of 1036 ppm The net increase when the gel was used first

The difference between these values was not statisticallywas 661 ppm.

Thus, the two products were also equivalent in terms of the retentionsignificant.

of fluoride on surface enamel after an average of 16 days

END OF FINAL REPORT -0

Date