Abstracts of the April 2007 Issue

Considerations about enamel microabrasion after 18 years

Renato Herman Sundfeld, dds, ms, phd, Theodore P. Croll, dds, André Luiz Fraga Briso, dds, ms, phd,Rodrigo Sversut de Alexandre, dds, ms, phd & Daniel Sundfeld Neto, dds

Abstract: Purpose: To review of the current status of enamel microabrasion method and its results 18 years after the development and application of this method. Methods: A technique performing enamel microabrasion with hydrochloric acid mixed with pumice and other techniques employing a commercially available compound of hydrochloric acid and fine-grit silicon carbide particles in a water-soluble paste have been described. Much has been learned about the application of this esthetic technique, long-term treatment results and microscopic changes to the enamel surface that has significant clinical implications. The latest treatment protocol is presented and photographic case histories document the treatment results. Clinical observations made over 18 years are discussed. Results: According to our findings, the dental enamel microabrasion technique is a highly satisfactory, safe and effective procedure. (Am J Dent 2007;20:67-72).

Clinical significance: The enamel microabrasion technique was developed as an method of eliminating enamel texture irregularities and discoloration defects and improving the appearance of teeth. It is a conservative procedure that has proven to be safe and clinically effective.

: Dr. Renato Herman Sundfeld, Department of Restorative Dentistry, Araçatuba Dental School–UNESP, Rua José Bonifácio 1193, São Paulo, CEP16015-050, Brazil. E-: sundfeld@foa.unesp.br

Use of ultrasonography for the diagnosis of temporomandibular joint disorders: A review

Marcello Melis, dmd, rpharm, Simona Secci, md & Caroline Ceneviz, dds, ms

Abstract: Purpose: To evaluate the reliability of ultrasonography in the diagnosis of temporomandibular joint (TMJ) disorders. Methods: A review of the literature was performed, searching for all articles published between 1966 and 2006, and examining the ones which met the selection criteria. Results: Ultrasonography sensitivity ranged from 13-100% for the evaluation of disc displacement (DD), from 70.6-83.9% for the evaluation of joint effusion (JE), and from 70-94% for the evaluation of condylar erosion (CE). Specificity ranged from 62-100% for the evaluation of DD, from 73.7-100% for the evaluation of JE, and from 20-100% for the evaluation of CE. Accuracy ranged from 51.5-100% for the evaluation of DD, from 72.2-95% for the evaluation of JE, and from 67-94% for the evaluation of CE. (Am J Dent 2007;20:73-78).

Clinical significance: Ultrasonography is a noninvasive and inexpensive diagnostic procedure that can be suggested for the evaluation of TMJ disorders, with particular accuracy in the detection of disc displacement and joint effusion. Limitations are especially related to the scarce accessibility of the medial part of the TMJ structures, and the need for trained and calibrated operators.

: Dr. Marcello Melis, Via Grosseto, 1, 09125 Cagliari, Italy. E-: marcellomelis01@libero.it

Clinical effectiveness of a dentifrice containing triclosan and a copolymer for controlling breath odor
 

Naresh C. Sharma, dds, H. Jack Galustians, bs, Jimmy Qaqish, bs, Anna Galustians, bs, Kedar Rustogi, dds, Margaret E. Petrone, jd, Patricia Chaknis, bs, Laura García, bs, Anthony R. Volpe, dds, ms & Howard M. Proskin, phd

Abstract: Purpose: To investigate in a double-blind clinical study the effectiveness of a dentifrice containing triclosan and a copolymer (Colgate Total Toothpaste) for controlling breath odor 12 hours after brushing the teeth. Methods: A panel of four expert judges using a nine-point hedonic scale evaluated breath odor. Following a baseline evaluation of breath odor, prospective study subjects who presented breath odor scores above the threshold value for unpleasant breath odor were stratified by score, and randomized into two treatment groups. Subjects were provided with a soft-bristled toothbrush, and brushed their teeth thoroughly in their regular and customary manner with their assigned dentifrice. Subjects refrained from dental hygiene, breath mints, or mouthrinses for the next 12 hours, after which they were once again evaluated for breath odor. 76 adult male and female subjects from the Mississauga, Ontario, Canada area participated in the study. Results: At 12 hours after brushing their teeth, subjects in both dentifrice treatment groups presented mean breath odor scores which were statistically significantly lower than the mean scores observed at baseline. However, the difference between the mean 12-hour breath odor score for the Colgate Total group was 4.65, which is within the range of values corresponding to pleasant breath odor; whereas the mean 12-hour breath odor score for the placebo group was 6.11, which is above the threshold value corresponding to unpleasant breath odor. Thus, the results of this double-blind study, conducted according to Guidelines by the Council on Scientific Affairs of the American Dental Association, support the conclusion that Colgate Total dentifrice provides effective control of breath odor at 12 hours after brushing the teeth. (Am J Dent 2007;20:79-82).

Clinical significance: The results of this double-blind study support the conclusion that Colgate Total dentifrice provides effective control of breath odor at 12 hours after brushing the teeth.

: Dr. Anthony R. Volpe, Colgate-Palmolive Technology Center, 909 River Road, Piscataway, NJ 08854, USA. E-: tony_volpe@colpal.com

Degradation of thermo-mechanically loaded adhesive Class V restorations after 18 months of water storage

Tissiana Bortolotto, dr med dent, Marco Ferrari, md, dds, phd, Franklin Tay, bdsc (hons), phd & Ivo Krejci, prof dr med dent

Abstract: Purpose: To assess in vitro the hydrolytic stability of adhesive systems in Class V composite restorations bonded to enamel and dentin. Methods: 16 groups of Class V cavities restored with different adhesive systems and challenged with thermal and mechanical loading under the simulation of dentin fluid were evaluated after an 18-month period of water storage at 37°C. The marginal adaptation of these restorations was quantified by evaluation of gold-coated epoxy replicas with scanning electron microscopy at x200 magnification. Results: The percentages of “continuous margin” after 18 months of water storage with respect to the total marginal length ranged from 62.9 (5.4)% to 18.5 (3.2)% with significant differences observed among the groups (Bonferroni test P< 0.05). The range in enamel was from 71.8 (14.2)% to 8.9 (6.4)% and in dentin from 94.3 (5.1)% to 0.0 (0.0)%. Marginal adaptation of all the materials tested was affected by water storage, either in enamel, in dentin, or both. None of the restorative systems tested exhibited hydrolytically stable marginal adaptation. (Am J Dent 2007;20:83-89).

Clinical significance: Both enamel and dentin margins of adhesive restorations showed hydrolytic degradation. This may compromise the clinical performance of the restorations.

: Prof. Dr. Ivo Krejci, Division of Cariology and Endodontology, School of Dentistry, University of Geneva, 19, Rue Barthélemy-Menn, CH-1205 Geneva, Switzerland. E-: Ivo.Krejci@medecine.unige.ch

Effect of manual and powered toothbrushes on orthodontic bracket bond strength

Franklin García-Godoy, dds, ms & Marko de Jager, phd, ms
 

Abstract: Purpose: To assess in vitro the effect of manual and powered toothbrushes on the bond strength of orthodontic brackets. Methods: Specimens of orthodontic brackets bonded to the surfaces of extracted teeth were exposed to one of two powered toothbrushes (Sonicare Elite, Braun Oral-B 3D Excel) or a manual toothbrush (Oral-B 35) for the equivalent of a 2-year exposure to brushing in the presence of toothpaste slurry. Control specimens underwent no brushing. For each treatment, 10 specimens were tested and evaluated. Shear bond strength of the orthodontic bracket to the tooth surface was assessed after exposure to simulated brushing. ANOVA was used to analyze the data. Results: No differences in orthodontic bracket bond strength were observed between any of the three treatments and the control. The evaluated toothbrushes did not adversely affect the in vitro bonding strength of orthodontic brackets, suggesting they are safe to use in orthodontic patients. (Am J Dent 2007:90-92).

Clinical significance: The evaluated toothbrushes did not adversely affect the in vitro bonding strength of orthodontic brackets, suggesting they are safe to use in orthodontic patients.

:Dr. Franklin García-Godoy, College of Dental Medicine, Nova Southeastern University, 3200 South University Drive, Fort Lauderdale, FL 33328, USA. E-: fgarciagodoy@gmail.com

Remineralization of primary root caries lesions using an amine fluoride rinse and dentifrice twice a day

Lars G. Petersson, dds, odont dr, Ulf Hakestam, dds, odont dr, Amir Baigi, phd & Edward Lynch, bsentsc, fds, ma, phd

Abstract: Purpose: To assess the clinical effect of daily use of a toothpaste and mouthrinse, both containing amine fluoride, on primary root caries lesions (PRCL) in an adult caries risk population. Methods: A clinical trial based on male and female subjects, 55-81 years of age, randomly assigned into two equal groups (Groups A and B). Fifty subjects allocated to Group A used a fluoride toothpaste twice a day, (Elmex sensitive toothpaste, 1400 ppm F) plus a mouthrinse twice a day with 10 ml of a fluoride solution (Elmex sensitive rinse containing 250 ppm F). The fluoride used was amine fluoride and potassium fluoride (AmF/KF, 1:1). Subjects in Group B used the same fluoride toothpaste plus a placebo mouth rinse solution without fluoride. At baseline, a total of 420 PRCL were clinically recorded as either soft (score 3) or leathery (score 2). Parallel and blind recordings measuring electric resistance of the selected PRCL were performed at baseline and after 3, 6, 9 and 12 months using an electrical caries monitor (ECM). Prevalence of tooth sensitivity and subject’s satisfaction was also measured in the two groups. Results: The clinical results showed statistically significant higher numbers of reversals of soft (score 3) and leathery (score 2) PRCL in Group A compared to Group B. After 12 months, the number of soft PRCL (score 3) decreased in Group A from 74% at baseline to 11% compared with 73% to 46% in Group B. After 12 months, 67% of the PRCL became hard (score 1) in Group A compared to only 7% in Group B (P< 0.001). Statistically significant higher (P< 0.001) ECM mean (sd) log₁₀ resistance values were recorded for the subjects in Group A, 2.67 (2.56) kOhm compared to 2.12 (1.88) kOhm in Group B. Tooth sensitivity was substantially reduced after 12 months, by 56% in Group A compared to 20% in Group B. (Am J Dent 2007;20:93-96).

Clinical significance: The results of this paper show that rinsing and toothbrushing with amine fluoride dentifrice twice a day significantly remineralizes active soft and leathery primary root caries lesions with a substantial reduction of tooth sensitivity. The ECM is a useful and supplementary tool for objectively measuring remineralization of primary root caries lesions.

: Dr. Lars G. Petersson, Dental and Maxillofacial Unit, Central Hospital, Halmstad, S-301 85, Sweden. E-: lars.g.petersson@thalland.se

Micromorphology and surface roughness of sound and demineralized enamel and dentin bleached with a 10% carbamide peroxide bleaching agent

Roberta Tarkany Basting, dds, ms, scd, phd Antonio Luiz Rodrigues Jr., dds, ms, scd & Mônica Campos Serra, dds, ms, scd

Abstract: Purpose: To evaluate the micromorphology and surface roughness of sound and demineralized enamel and dentin treated with a 10% carbamide peroxide bleaching agent in situ for 3 weeks. Methods: A 10% carbamide peroxide bleaching agent, Opalescence (OPA) was evaluated and a placebo agent (PLA) not containing carbamide peroxide, was used as a control group. Forty dental slabs [10 sound enamel slabs (SE), 10 demineralized enamel slabs (DE), 10 sound dentin slabs (SD) and 10 demineralized dentin slabs (DD)] were randomly fixed on the facial surface of the first maxillary molars and second maxillary premolars of 10 volunteers. Demineralized enamel and dentin fragments were obtained by a dynamic model using demineralizing and remineralizing solutions. The volunteers were divided into two groups that received the bleaching or the placebo agent in different sequences and periods in a double blind 2 x 2 cross-over study with a wash-out period of 2 weeks. Roughness was performed on the slab surfaces followed by scanning electron microscope (SEM) evaluations. The images were evaluated by three calibrated examiners in duplicate in two different periods at x1500 (SE and DE) and x2000 original magnification (SD and DD). Results: The Wilcoxon test showed significant differences in roughness for SE and DE treated with OPA or PLA, with rougher surfaces treated with OPA. No differences in roughness were observed for SD or DD treated with OPA or PLA. As the Kappa value for the inter-examiner agreement of SEM evaluations showed “moderate” reproducibility (0.41< k< 0.60) in Period 1 and “substantial” (0.61< k< 0.8) in Period 2, the latter was considered for the statistical analysis. The McNemar test showed no significant differences between SE, DE, SD or DD treated with OPA or PLA. (Am J Dent 2007;20:97-102).

Clinical significance: In a roughness evaluation, enamel surfaces seemed to be more affected by bleaching agents than dentin. However, these changes were not reflected as micromorphology alterations.

: Prof. Dr. Roberta Tarkany Basting, Faculdade de Odontologia e Centro de Pesquisas Odontológicas São Leopoldo Mandic, Departamento de Odontologia Restauradora – Dentística, Rua José Rocha Junqueira, 13, Swift, Campinas, SP, CEP: 13045-755 Brazil. E-: rbasting@yahoo.com

Influence of ceramic pre-treatments on tensile bond strength and mode of failure of resin bonded to ceramics

Noéli Boscato, dds, msc, Álvaro Della Bona, dds, mmedsci, phd & Altair Antoninha Del Bel Cury, dds, phd

Abstract: Purpose: To evaluate the effect of ceramic surface treatments on tensile bond strength (σ) and the mode of failure of a resin bonded to a feldspathic glass and a low-crystalline ceramic, testing the hypothesis that a silica coating treatment is unnecessary for both the glass and the low-crystalline ceramic. Methods: 10 blocks of each the feldspathic glass (V7-VITAVM7) and the leucite-based ceramic (E1-IPS Empress) were fabricated and polished. Five blocks of each ceramic were treated as follows: 9.5% hydrofluoric acid for 60 seconds; and silica coating using Cojet System for 15 seconds. After silane coating, an adhesive resin and a composite were applied and polymerized. The composite-ceramic blocks were cut to produce bar-shaped specimens (n=30) that were stored in distilled water at 37°C for 7 days before tensile loading to failure in a universal testing machine. Data were statistically analyzed using analysis of variance, Tukey’s test (α = .01) and Weibull analysis. Fracture surfaces were examined to determine the mode of failure. Results: The Weibull modulus (m) and mean σ value (MPa) of Group E1HF (29.8±4.5) were significantly higher than other Groups (P=.0001). There was no statistical difference between Groups E1CS (24.6±5.6) and V7HF (22.3±4.0). Group V7CS showed the lowest m and mean σ values (15.7±6.9) (P=.0001). All fractures occurred within the adhesion zone. (Am J Dent 2007;20:103-108).

Clinical significance: Silica coating is not the pre-treatment of choice for bonding the glass and the low-crystalline ceramic to resin. Hydrofluoric acid etching produced the highest m and σ values of resin to both ceramics (V7 and E1) tested.

: Dr. Alvaro Della Bona, University of Passo Fundo, School of Dentistry, Campus I, Highway BR285, PO Box 611, Passo Fundo, RS, 99001-970, Brazil. E-: dbona@upf.br

Degradation of resin-bonded human dentin after 3 years of storage

Franklin García-Godoy, dds, ms, Franklin R. Tay, BDSc (Hons), FADM, PhD, David H. Pashley, DMD, FADM, PhD, Albert Feilzer, DDS, PHD, L. Tjäderhane, DDS, PhD & Edna L. Pashley, DMD, MEd

Abstract: Purpose: To test, in vitro, the null hypothesis that there was no difference in the ultrastructure of adhesive-bonded, acid-etched dentin aged under accelerated conditions in mineral oil or artificial saliva. Methods: Beams of human dentin bonded with three total-etch adhesives were retrieved from the two storage media after 3 years and prepared for transmission electron microscopy. Results: Hybrid layers from specimens aged in mineral oil exhibited structural integrity of the collagen network. Conversely, abnormal hybrid layers were seen in specimens aged in artificial saliva, with progressive disintegration of the fibrillar network to the extent that it was beyond detection by collagen staining. Self-destruction of collagen matrices can occur in resin-infiltrated dentin, and to a lesser degree, in mineralized dentin in the absence of bacterial or salivary enzymes. (Am J Dent 2006;19:109-113).

Clinical significance: Self-destruction of collagen matrices can occur in resin-infiltrated dentin, and to a lesser degree, in mineralized dentin in the absence of bacterial or salivary enzymes.

: Dr. Franklin García-Godoy, College of Dental Medicine, Nova Southeastern University, 3200 South University Drive, Fort Lauderdale, Florida 33328, USA. E-: fgarciagodoy@gmail.com

Microtensile bond strength of sealant and adhesive systems applied to occlusal primary enamel

Ana Cláudia D. Ramires-Romito, dds, ms, Alessandra Reis, dds, phd, Alessandro Dourado Loguercio, dds, ms, phd, Vinícius D. Hipólito, dds, ms, Mário Fernando de Goes, dds, ms, phd, Julio da Motta Singer, phd & Rosa Helena Miranda Grande, dds, ms, phd

Abstract: Purpose: To compare the microtensile bond strength (µTBS) of a self-etch adhesive system (OptiBond Solo Self-Etch Adhesive System), two total etch adhesive system (OptiBond FL; OptiBond Solo), and a conventional sealant (Clinpro) applied to the occlusal surface of primary molars under saliva contamination. Methods: Sealant and adhesive systems were applied under manufacturers’ specifications with or without previous saliva contamination. After storage in distilled water at 37ºC for 24 hours, the specimens were longitudinally sectioned perpendicularly to the adhesive interface to obtain sticks (0.6 mm²) which were tested under a tensile load of 0.5 mm/minute. The bond failure modes were evaluated via scanning electron microscope. Repeated measures ANOVA followed by multiple comparisons using Bonferroni’s technique was used to evaluate the effects of adhesive system and saliva contamination. The pre-test debonded specimens were included in the computation of the µTBS of each tooth. Results: No association between failure mode and the values of µTBS was observed (P= 0.3605). The majority of fractures were of mixed type; no cohesive failure of enamel or composite resin was observed. No significant effect of saliva contamination was detected (P= 0.2044). OptiBond FL and Clinpro had equivalent average µTBS (34.5 ± 2.2 MPa and 45.1 ± 3.2 MPa, respectively) which are significantly higher than the corresponding average µTBS for OptiBond Solo Plus and OptiBond Solo SE which may also be considered equivalent (19.1 ± 2.3 MPa and 9.8 ± 2.3 MPa, respectively). (Am J Dent 2007;20:114-120).

Clinical significance: Except for the conventional sealant, all adhesive systems showed similar performance on dry and contaminated primary enamel surface. However, the total etch two-step adhesive system provided the highest resin-enamel bond strength values on the occlusal surface of primary molars and seemed to be the best option for fissure sealing.

: Prof. Dr. Rosa Helena Miranda Grande, Department of Dental Materials, Faculty of Dentistry, University of São Paulo, Avenida Lineu Prestes, 2227 – Cidade Universitária, 05508-000 São Paulo, SP, Brazil. E-: grande@usp.br

Fracture strength of restored premolars

Guilherme Brião Camacho, ms, dds, phd, Mariane Gonçalves, ms, dds, phd, Tomio Nonaka, ms, dds, phd & Angela Brys Osório, ms

Abstract: Purpose: To evaluate the fracture resistance (axial compressive strength) of premolars restored with different dental materials under two axial loads. Methods: Fracture strength was performed using two metal spheres with 3 mm and 9 mm diameter. Five restorative techniques were chosen for MOD cavity preparations (n=10): (1) direct resin composite restorations (Z-250); (2) indirect resin composite restorations (Z-250 and RelyX); (3) ceramic inlays (Vitadur Alpha); (4) conventional amalgam restorations (GS-80); (5) bonded amalgam restorations. The restored teeth were compared to human caries-free premolars (Group 6/control). Enforce resin cement was used for ceramic and amalgam adhesive restorative techniques, according to the manufacturers’ instructions. Whenever required, the teeth were conditioned by the total etch technique. Results: The ANOVA analysis pointed out a significant difference among the groups (P< 0.01) and the “site” factor (P< 0.1). The ceramic restorations presented the highest values for fracture strength and were similar to the control group. The statistical results of direct and indirect resin composite restorations were similar but inferior to the control group. The amalgam restorations (conventional and bonded) presented the lowest values, with no difference between them. All amalgam groups displayed lower strengths when the load was applied on the central fossa (3 mm Ø sphere) compared to load applied on cusps (9 mm Ø sphere). (Am J Dent 2007;20:121-124).

Clinical significance: The loads similar to chewing of solid food is relevant to fracture strength, which occurs at the central fossa where the risk of fracture is higher. The fracture strength of the different restorative techniques was product-related.

: Prof. Dr. Mariane Gonçalves, Faculty of Dentistry, Department of Dental Materials and Prosthesis, University of Ribeirão Preto, Avenida do Café, s/n, Ribeirão Preto – SP, CEP 14040-904, Brazil. E-: ane.gon@netsite.com.br

One-year clinical performance of self-etch adhesives in posterior restorations

Jorge Perdigão, dmd, ms, phd, Maristela Dutra-Corrêa, dds, ms, Natália Castilhos, dds, André R.P. Carmo, dds, ms, phd, Camillo Anauate-Netto, dds, ms, phd, Hiram J.D. Cordeiro, dds, ms, phd, Ricardo Amore, dds, ms, phd & Hugo R. Lewgoy, dds, ms, phd

Abstract: Purpose: To evaluate the 1-year clinical performance of three self-etching adhesives (Adper Prompt L-Pop, Clearfil S³ Bond, iBond) in posterior composite restorations using one etch&rinse adhesive (One-Step Plus) as control. Methods: Upon approval by the Institutional Review Board, 121 restorations were inserted in 38 subjects. The adhesives were applied as per manufacturers’ instructions. Preparations were restored with a nanofilled resin composite (Filtek Supreme) and evaluated at baseline, 6 months, and 1 year. Statistical analyses included the Chi-square distribution with the McNemar non-parametric test (P< 0.05). Results: At 1 year, 111 restorations in 35 subjects were evaluated using the USPHS modified criteria. No significant changes were observed for the etch&rinse adhesive One-Step Plus. At 1 year the number of Alfa ratings decreased significantly for Clearfil S³ Bond and for iBond in the categories color match, marginal staining, and marginal adaptation. For Adper Prompt L-Pop, marginal adaptation at 1 year was significantly worse than at baseline. Postoperative sensitivity to air improved significantly for Adper Prompt L-Pop, Clearfil S³ Bond, and iBond. When the evaluation criteria were paired at 1 year, iBond resulted in a significantly lower number of Alfa ratings than any of the other adhesives for color match, marginal staining, and marginal adaptation. One-Step Plus resulted in a greater number of Alfa ratings for marginal adaptation than either Adper Prompt L-Pop or Clearfil S³ Bond. Marginal adaptation was significantly better for Clearfil S³ Bond than for Adper Prompt L-Pop. The post-operative sensitivity measured at 1 year for Adper Prompt L-Pop was statistically better than that for One-Step Plus. (Am J Dent 2007:20:125-133).

Clinical significance: Etch&rinse adhesives are still the benchmark for clinical performance in posterior restorations. Some self-etch adhesives may not perform at an acceptable level.

: Dr. Jorge Perdigão, Division of Operative Dentistry, Department of Restorative Sciences, University of Minnesota, 8-450 Moos Tower, 515 SE Delaware St., Minneapolis, MN 55455, USA. E-: perdi001@umn.edu

Inhibition of enamel demineralization by a bioerodible fluoridated resin

Jeffrey Miles Mazzawi, dmd, Timothy Henson, dmd & Kevin J. Donly, dds, ms

Abstract: Purpose: To investigate the efficacy of a bioerodible fluoridated resin on inhibition of enamel demineralization. Methods: Eighteen extracted permanent molars were sectioned mesiodistally to obtain 36 caries-free enamel surfaces. Each sample was prepared by painting an acid-protective varnish, excluding a 2 x 8 mm window on either the buccal or lingual surface. The windows of exposed enamel were randomly divided into three separate groups (n= 12). Group 1 received an application of a 5% (by weight) sodium fluoride varnish. Group 2 had an experimental 5% sodium fluoride bioerodible resin applied to the window. Group 3 was left untreated and acted as a control. The samples were then exposed to an artificial caries challenge for 17 days, until a visible white spot lesion had been created on the control group. The samples were brushed for 1 minute daily. Following the acid challenge, the teeth were sectioned longitudinally to obtain 100 µm sections. Sections were then photographed under polarized light. Quantitatively the areas of the lesions were measured by utilizing a computerized imaging system. Finally, a comparison was made between mean lesion sizes of the sample groups in order to determine their respective efficacy of enamel demineralization inhibition. Results: The mean areas (µm)² of the artificial lesions (± SD) were: bioerodible fluoridated resin 3,785 ± 1,794; fluoride varnish 7,362 ± 2,853, and control 11,398 ± 4,238. ANOVA was performed and identified a significant variance (P< 0.001). Tukey's multiple comparison test demonstrated that bioerodible fluoridated resin had significantly less enamel demineralization than the fluoride varnish and control groups (P< 0.05). The fluoride varnish group demonstrated significantly less enamel demineralization than the control group (P< 0.05). (Am J Dent 2007;20:134-136).

Clinical significance: A bioerodible fluoridated resin could offer an enhanced demineralization inhibition effect compared to currently available products.

: Dr. Kevin J. Donly, Department of Pediatric Dentistry, Dental School, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX 78229-3900, USA. E-: donly@uthscsa.edu