Association Between Dental Calculus and Hypertension Phenotypes in Highly Fit Adults: CHIEF Oral Health Study.

BACKGROUND: Poor oral health evaluated by presence of dental calculus has been associated with hypertension (HTN) among middle- and old-aged adults. However, it is unclear for the association of HTN phenotypes with dental calculus in young adults. METHODS: This study examined the association between dental calculus and HTN in 5,345 military personnel, aged 19-45 years, without antihypertensive medications therapy in Taiwan from 2018 to 2021. Dental calculus was defined as presence of supragingival calculus in any teeth, except impacted teeth, and third molar. Combined HTN (CHTN) was diagnosed as systolic blood pressure (SBP) ≥130 mm Hg and diastolic blood pressure (DBP) ≥80 mm Hg. Isolated systolic and diastolic HTN were, respectively, defined as SBP ≥130 mm Hg only (ISHTN) and DBP ≥80 mm Hg only (IDHTN). Multiple logistic regression with adjustments for sex, age, toxic substance use, anthropometrics, lipid profiles, fasting glucose, and blood leukocyte counts were used to determine the association between dental calculus and HTN phenotypes in young adults. RESULTS: The prevalence of those with dental calculus, CHTN, ISHTN, and IDHTN was 20.8%, 10.8%, 10.2%, and 7.0%, respectively. The dental calculus was associated a greater possibility with CHTN [odds ratio (OR) and 95% confidence interval: 1.60 (1.31-1.95)]. However, the associations of dental calculus with ISHTN and IDHTN were null [OR: 1.05 (0.81-1.27) and 1.12 (0.86-1.46), respectively]. CONCLUSIONS: Our findings suggest that among young adults, poor oral health manifested by presence of dental calculus was associated with a greater possibility of CHTN, while not for ISHTN and IDHTN.

Do active ingredients in non alcoholic chlorhexidine mouth wash provide added effectiveness? Observations from a randomized controlled trial.

BACKGROUND AND OBJECTIVE: Chlorhexidine (CHX) is the most tested and leading oral antiseptic agent. Zinc as an active ingredient has shown additive and synergistic effect and when Sodium fluoride (NaF) was used it failed to show added effectiveness and the combined effect of NaF and Zinc chloride (ZnCl2) both as active ingredients has never been evaluated. The present study assessed the effectiveness of active ingredients and to compare the frequency of adverse events occurring with traditional CHX and CHX+NaF+ZnCl2. MATERIAL AND METHODS: A randomized double blind crossover trial was executed with 24 subjects participating in two consecutive experimental phases of 21 days each with CHX and CHX+NaF+ZnCl2 mouth rinses. Each individual was assessed for gingivitis, plaque, supragingival calculus and extrinsic stains at baseline and after experimental phase and adverse events experienced were recorded. RESULTS: There was a significant difference (p = 0.014) between the two experimental mouth rinses for their effectiveness on gingivitis. In the CHX group, the gingival score on D21 was significantly greater by 0.13 than DO while with CHX+NaF+ZnCl2 there was a decrease in gingival score by 0.09 which was insignificant. No significant difference was observed between the interventions for plaque accumulation and formation of extrinsic stains. The difference in the mean calculus score at baseline and after experimental phase was 1.47 for CHX+NaF+ZnCl2 in contrast to 1.93 among CHX group. Oral itching, oral soreness, apthous ulcers and dryness were reported by many subjects while burning sensation was reported by very few volunteers. There was no significant difference for occurrence of adverse events between the two experimental mouthrinses. CONCLUSIONS: CHX+NaF+ZnCl2 mouth rinse was found to be significantly more effective in the reduction of gingivitis and supragingival calculus. No significant difference was found for the occurrence of dental plaque, extrinsic stains and adverse events between the interventions.

Ethylcellulose inserts of an orphan drug for periodontitis: preparation, in vitro, and clinical studies.

Ethylcellulose inserts of niridazole fabricated by casting were studied for in vitro release and in vivo clinical effectiveness. The in vitro drug release was steady and sustained for over 7 days and followed diffusion kinetics. Selected batch, EN3, was evaluated clinically in patients with periodontitis for 6 months. A significant improvement (alpha < or = 0.05) in clinical indices from baseline was observed. Intergroup study revealed a significant (alpha < or = 0.01) change in the bleeding index, gingival index, plaque index, calculus criteria, and pocket depth. Significant reduction in total bacterial count in gingival crevicular fluid was observed before and postdevice insertion, as well as between control and treatment groups.

Anticalculus effect of a cetylpyridinium chloride/zinc gluconate mucoadhesive gel: results of a randomized, double-blind, controlled clinical trial.

OBJECTIVE: This randomized, double-blind, controlled clinical trial investigated the anticalculus effect of a cetylpyridinium chloride/ zinc gluconate (CPC/ZG) mucoadhesive gel. METHODOLOGY: The 80 adults from the San Francisco area who fulfilled the enrollment criteria were stratified based on total Volpe-Manhold Index (VMI) scores (low, medium, or high), gender, and other demographic data. Within these strata, they were randomly assigned to the CPC/ZG gel group or the placebo gel group, and underwent a baseline oral soft tissue (OST) examination. Subjects were dispensed Oral-B Indicator 35 Compact Head soft toothbrushes and Colgate Cavity Protection MFP toothpaste, and instructed to brush twice daily using these products. Every night for three months, following the nighttime brushing and just before retiring, subjects applied their assigned treatment gel to the lingual surfaces of the six mandibular anterior teeth. They were instructed not to eat or drink until morning and to avoid using other methods of interdental cleaning between the treated teeth, except to remove impacted food. Total VMI scores and OST examination findings obtained at three months were compared with baseline findings. RESULTS: Seventy-eight (78) of the 80 subjects complied with the protocol and completed the study. After three months of treatment, the CPC/ZG group showed a 30% decrease in mean VMI score compared with a 0% decrease in the placebo group. OST examination at three months revealed no serious adverse events in either group. CONCLUSION: Results of this clinical trial indicate that regular use of the CPC/ZG gel, with or without the use of floss or other interdental cleaning products, yields a statistically significant reduction in calculus.

The plaque and gingivitis reducing effect of a chlorhexidine and aluminium lactate containing dentifrice (Lacalut aktiv) over a period of 6 months.

AIM: The aim of the study was to determine the plaque and gingivitis reducing effect of a dentifrice containing chlorhexidine and aluminium lactate compared with a control toothpaste during the course of 6 months. MATERIAL AND METHODS: This randomized, double-blind study looked prospectively at participants over a 6-month period. Plaque, gingivitis, calculus formation and tooth staining were assessed in 59 participants, who were divided into parallel groups. The participants used either a chlorhexidine and aluminium lactate-containing toothpaste (test group) or a minus active control toothpaste (control group). Parameters were assessed at baseline and again after 1, 3 and 6 months. RESULTS: After 6 months of product use, both groups had less gingivitis compared with the baseline evaluation (p<0.001). At this time point, the test group showed a statistically significant lower gingival index values compared with the control group (p=0.001). No statistically significant differences between either the groups or time points were detected with regard to plaque index and the development of calculus and staining. CONCLUSION: Although there was a statistically significant difference at 6 months between test and control groups, this difference was too small to be considered clinically meaningful.

Efficacy of Carisolv as an adjunctive therapy to scaling and root planing on subgingival calculus removal.

The purpose of this study was to evaluate the effectiveness of subgingival application of Carisolv gel as an adjunctive therapy to scaling and root planing (SRP) on calculus removal compared to conventional instrumentation. Forty-five teeth requiring extraction due to severe periodontal disease were randomized to the following treatments: 1) SRP alone; 2) placebo gel + SRP; 3) Carisolv gel + SRP. Either test or placebo gel was applied subgingivally for 1 min and then the root were instrumented until a smooth and calculus-free surface was achieved. Instrumentation time and the number of strokes required were recorded. After extraction, the efficacy of root surface instrumentation was measured by percentage of remaining calculus. There was no statistically significant difference (p>0.05) between the treatment groups regarding either time required for instrumentation or the percentage of residual calculus. The subgingival application of Carisolv gel prior to SRP did not provide any additional benefit to root instrumentation compared to scaling and root planing alone.

Efficacy of Carisolv™ as an adjunctive therapy to scaling and root planing on subgingival calculus removal

The purpose of this study was to evaluate the effectiveness of subgingival application of Carisolv™ gel as an adjunctive therapy to scaling and root planing (SRP) on calculus removal compared to conventional instrumentation. Forty-five teeth requiring extraction due to severe periodontal disease were randomized to the following treatments: 1) SRP alone; 2) placebo gel + SRP; 3) Carisolv™ gel + SRP. Either test or placebo gel was applied subgingivally for 1 min and then the root were instrumented until a smooth and calculus-free surface was achieved. Instrumentation time and the number of strokes required were recorded. After extraction, the efficacy of root surface instrumentation was measured by percentage of remaining calculus. There was no statistically significant difference (p>0.05) between the treatment groups regarding either time required for instrumentation or the percentage of residual calculus. The subgingival application of Carisolv™ gel prior to SRP did not provide any additional benefit to root instrumentation compared to scaling and root planing alone.

O objetivo deste estudo foi avaliar a efetividade da aplicação subgengival do gel Carisolv™ em associação aos procedimentos de raspagem e alisamento radicular (RAR) na remoção do cálculo dental aderido à superfície radicular, quando comparado à terapia periodontal mecânica convencional. Foram utilizados 45 dentes indicados para a exodontia devido à doença periodontal avançada, os quais foram divididos em três grupos de tratamento: 1) RAR apenas; 2) placebo + RAR; 3) Carisolv™ + RAR. O tempo despendido e o número de movimentos realizados para a instrumentação das superfícies radiculares foram avaliados durante o tratamento. Em seguida, os dentes foram extraídos e avaliados quanto ao percentual de cálculo residual, por meio de um sistema computadorizado de análise de imagens. Não houve diferença estatisticamente significante (p>0,05) entre os grupos com relação ao tempo requerido para os diferentes tratamentos, assim como quanto ao percentual de cálculo residual. Os resultados indicaram que a aplicação do Carisolv™ não promoveu benefícios adicionais àqueles obtidos com a terapia mecânica convencional na remoção do cálculo subgengival.

Effect of locally delivered doxycycline hyclate on human fibroblast attachment to subgingival calculus.

BACKGROUND: Clinical studies using locally applied doxycycline hyclate (DHV) have demonstrated significant probing depth reduction and gain in clinical attachment as a monotherapy without scaling and root planing. The mechanism for this attachment level gain to the non-root planed tooth is not understood. The purpose of this study was to investigate the effect of locally applied doxycycline hyclate on human gingival fibroblast attachment to subgingival calculus on contaminated root surfaces. METHODS: Two separate experiments were performed, both on subgingival calculus. In experiment 1, teeth with subgingival calculus were treated with either doxcycycline hyclate in bioabsorbable vehicle (DHV) or with vehicle control (VC) in vivo. In experiment 2, teeth with subgingival calculus were treated with DHV, VC, scaling and root planing (SRP), or no treatment in vitro. The amount of cell attachment to calculus-covered root surfaces was quantitatively compared using a fluorescent dye assay and epifluorescence microscope. Values for cell attachment are presented as the mean standard deviation of the mean. The data were evaluated using Student t test. RESULTS: In both experiments, there was no statistically significant difference in fibroblast attachment in the DHV, VC, or no treatment groups (P >0.05). The SRP group showed significantly more cellular attachment to tooth surfaces formerly covered by subgingival calculus than all other groups (P <0.001). In general, more cells attached to cementum than to calculus. Root chips that showed no attachment to the subgingival calculus also had no cells attached to the adjacent cemental root surface. CONCLUSION: The addition of doxycycline hyclate in a bioabsorbable vehicle used as a locally delivered drug did not enhance the initial cellular attachment of human gingival fibroblasts to subgingival calculus or contaminated root surfaces.

A novel dentifrice technology for advanced oral health protection: A review of technical and clinical data.

Throughout the world, dentifrices have played a key role in the practice of good oral hygiene and promotion of better oral health. In addition to providing general dental cleaning, toothpastes also have served as an excellent vehicle for the introduction of new agents that deliver therapeutic and cosmetic benefits. Key examples of using dentifrices to provide added benefits include the introduction in 1955 of the first fluoridated toothpaste clinically proven to fight caries (Crest Cavity Protection) and the launch of the first tartar-control dentifrice (Crest Tartar Control) in the mid-1980s. To continue expanding the health and esthetic benefits offered by a single dentifrice, a multitude of agents have been investigated over the past 3 decades. The focus of these investigations has been in the multibenefit segment, the most widely used among US consumers.

Anticalculus efficacy and safety of a stabilized stannous fluoride/sodium hexametaphosphate dentifrice.

The purpose of this study was to assess the anticalculus efficacy and long-term safety of a new stannous fluoride dentifrice containing sodium hexametaphosphate. This trial was a randomized, double-blind, parallel-group, 6-month study where, after a prophylaxis, subjects brushed twice daily with either a stabilized 0.454% stannous fluoride/13% sodium hexametaphosphate dentifrice (Crest Pro-Health) or a marketed multibenefit triclosan/copolymer control dentifrice. Study subjects were known to form supragingival calculus and had previously demonstrated the ability to form at least 1.5 mm using the Volpe-Manhold Calculus Index over a 2-month pretest period. Comparisons between treatments for anticalculus efficacy were performed using analysis of covariance. Eighty subjects were randomized into one of two treatment groups after stratification on gender and baseline calculus scores and then monitored for calculus formation, soft tissue tolerance, and extrinsic stain. The mean calculus score for the stannous fluoride/sodium hexametaphosphate group was statistically significantly lower than that of the triclosan/copolymer group at both months 3 and 6 (P < .01). At month 3, the stannous fluoride/sodium hexametaphosphate group had an adjusted mean 54% lower than that of the triclosan/copolymer group. At month 6, the stannous fluoride/sodium hexametaphosphate group had an adjusted mean 56% lower than that of the triclosan/copolymer group. Both dentifrices were well tolerated and neither dentifrice group developed appreciable extrinsic stain over the 6-month trial period. Overall, the stannous fluoride/sodium hexametaphosphate dentifrice had superior anticalculus efficacy relative to the marketed triclosan/copolymer control and a comparable soft tissue safety and extrinsic stain profile.

Povidone-iodine as a periodontal pocket disinfectant.

OBJECTIVES AND BACKGROUND: Povidone-iodine [polyvinylpyrrolidone-iodine complex (PVP-iodine)] might constitute a valuable adjunct to current periodontal therapy because of its broad-spectrum antimicrobial activity, low potential for developing resistance and adverse reactions, wide availability, ease of use, and low financial cost. This investigation employed a randomized, split-mouth study design to determine the microbiological and clinical effects of 10% PVP-iodine subgingival irrigation in periodontitis lesions showing radiographic evidence of subgingival calculus. METHODS: Sixteen adults having at least one periodontal pocket of 6 mm or more in each quadrant of the dentition and harboring one or more periodontopathic bacteria participated in the study. In each subject, a study site in each quadrant was randomly chosen to receive either subgingival irrigation with 10% PVP-iodine together with scaling and root planing, scaling and root planing alone, subgingival irrigation with 10% PVP-iodine, or subgingival irrigation with sterile saline. Prior to therapy and at 5 weeks post-treatment, microbiological culture was carried out without knowledge of the clinical status or the type of treatment rendered. A blinded clinical examiner determined presence of dental plaque, probing pocket depth, and gingival bleeding on probing. Microbiological and clinical data were analyzed using a repeated measures analysis of variance and Kruskal-Wallis rank test with the Tukey and Mann-Whitney post hoc tests. RESULTS: At 5 weeks post-treatment, subgingival irrigation with PVP-iodine together with scaling and root planing caused a 95% or greater reduction in total pathogen counts in 44% of pockets having >/= 6 mm depth whereas scaling and root planing alone, povidone-iodine irrigation alone and water irrigation alone caused 95% reduction of total pathogens only in 6-13% of similar study sites (P = 0.02). Reduction in mean pocket depth was 1.8 mm for the PVP-iodine/scaling and root planing group, 1.6 mm for the scaling and root planing group, and 0.9 mm for the PVP-iodine and the saline monotherapy groups, with statistical significance reached for the scaling and root planing group vs. the PVP-iodine group (P = 0.04) and for the scaling and root planing group vs. the saline group (P = 0.02). Reduction in visible dental plaque, which ranged from 38% to 62%, showed no significant differences among treatment groups. CONCLUSIONS: The addition of subgingival PVP-iodine irrigation to conventional mechanical therapy may be a cost-effective means of reducing total counts of periodontal pathogens and helping control periodontal disease. However, subgingival irrigation with PVP-iodine without concomitant mechanical debridement might not improve microbiological and clinical variables in comparison with saline irrigation, at least not in sites with radiographic evidence of subgingival calculus.

Anticalculus agents.

Most dentifrices and some mouthrinses now contain 1 or more active anticalculus agents to achieve so-called tartar control. The aim of this article is to review the research associated with the development of anticalculus agents and to evaluate in some detail, the efficacy of those agents which are currently available in dentifrice products.

Root substance removal with Er:YAG laser radiation at different parameters using a new delivery system.

BACKGROUND: The recently introduced Er:YAG laser radiation appears to be a promising alternative in treating dental hard tissue due to its thermo-mechanical ablation properties and the lack of thermal side effects. The present in vitro study attempted to evaluate the use of Er:YAG laser radiation in combination with a specially developed delivery system in removing calculus from root surfaces. METHODS: Fifty extracted anterior teeth, premolars and molars, were divided into 2 groups of 25 each with (group A) and without (group B) subgingival calculus. Source of radiation was an Er:YAG laser device with a wavelength of 2.94 microm, in the infrared optical spectrum, a pulse duration of 250 ns, and a pulse repetition rate of 15 pps. In each group, 6 teeth were irradiated with 300 laser pulses either at 60 mJ, 80 mJ, 100 mJ, or 150 mJ. The samples were continually moved linearly using a computer numeric controlled device. The volumetric evaluation of root substance removal was performed with a 3-dimensional laser scanning system (100,000 surface points per sample, accuracy: 5 microm) and special image analyzing software. A scanning electron microscopic (SEM) observation was performed to assess the laser induced ultrastructural changes on the root surfaces. Statistical analysis was carried out with ANOVA followed by the Scheff*e test and with regression analysis according to Pearson-Bravais at a level of significance of 5% (P <0.05). RESULTS: The linear measurement of substance removal on calculus samples (group A) revealed average depths between 174.38 (+/-16.13) microm and 501.85 (+/-111.01) microm. Defect depths on the teeth without calculus (group B) ranged from 37.78 (+/-14.03) microm to 484.44 (+/-80.63) microm. The SEM observation of laser-treated root surfaces revealed no signs of thermal damage; e.g., melting, fusion, or cracking. CONCLUSIONS: The results of the present study showed that a substance removal with Er:YAG laser radiation at lower energy densities is comparable, in effect, to that after conventional root surface instrumentation with curets. The results seem to indicate that calculus removal can be selectively done using lower radiation energies. Considering the favorable results of the SEM investigation, the use of the Er:YAG laser in periodontal therapy may be possible in the future.

Anticalculus effects of a novel, dual-phase polypyrophosphate dentifrice: chemical basis, mechanism, and clinical response.

A primary patient motivation for oral hygiene is effective cleaning. Dentifrice serves this function by including ingredients such as abrasives, surfactants, and specialized cleaning ingredients such as anticalculus agents. This introductory article aims to introduce professionals, educators, and researchers on the rationale behind the development of an improved cleaning dentifrice formulation, Crest Multicare Advanced Cleaning. This new dentifrice is based upon the application of an improved tartar control/cleaning ingredient that is a polymeric adjunct of a pyrophosphate anion commonly applied in tartar control and stain control whitening dentifrices. The polypyrophosphate anion, also referred to as sodium hexametaphosphate, produces superior activity and substantivity on oral surfaces as compared to both pyrophosphate and some other commonly used dental cleaning ingredients and cleaning/conditioning adjuncts. The increased activity and substantivity translate into significant improvements in the prevention of dental stains and supragingival calculus and in the non-abrasive removal of dental stains. This article describes the structure of polypyrophosphate as compared to the parent pyrophosphate molecule, the rationale for its improved chemistry, and, in particular, its tartar control chemistry. In addition, the fundamental mechanisms of calculus formation and inhibition are reviewed. Lastly, a preliminary clinical study evaluating the improved efficacy of a polypyrophosphate dentifrice is described where the tartar control activity of the polypyrophosphate dentifrice is shown to be superior to that of a clinically established and marketed industry standard pyrophosphate dentifrice.

Effect of clindamycin hydrochloride on oral malodor, plaque, calculus, and gingivitis in dogs with periodontitis.

Periodontal disease is considered the most common disease of dogs and cats. The clinical sign most frequently reported by clients is oral malodor. Clindamycin hydrochloride has been used for several years for the treatment of periodontal disease in both cats and dogs. This study was designed to assess the effect of clindamycin HCl when used in two different post-prophylaxis treatment regimens on oral malodor and periodontal disease in a controlled clinical trial. This study demonstrated that a 5-day postprophylaxis regimen was significantly effective in reducing oral malodor compared with a dental prophylaxis alone. Clindamycin HCl significantly reduced oral malodor from the animals' baseline levels through 42 days. In addition, although no effect was observed on periodontal pocket depth, this treatment regimen also resulted in significant reductions in dental plaque, dental calculus, and gingival bleeding.

Therapeutic effects of supervised chlorhexidine mouthrinses on untreated gingivitis.

AIM: The aim of the present study was to test the presumptive therapeutic effect of chlorhexidine digluconate in a population with untreated gingivitis and presence of abundant calculus. SETTING AND STUDY DESIGN: Sixty subjects (approximately mean age of 23.4) were recruited from a knitting factory in the Province of Guangdong, People's Republic of China. By applying a double-blind clinical trial design the participants were divided into two groups (Test and Control) and matched according to their mean GI scores. The Test group (n = 20) was assigned to two daily mouthrinses for 6 days per week using 0.12% chlorhexidine digluconate (Peridex). The Control group (n = 40) rinsed twice daily with a placebo solution. All the rinsings were supervised and timed for 45 s. No attempt was made to influence the oral hygiene habits of the participants. Prior to and after 3 months of the supervised rinsing, plaque was scored using the Plaque Index system (PII), and gingivitis was assessed using the criteria of the Gingival Index system (GI). Calculus was scored according to the Calculus Surface Severity Index system (CSSI), and stain was also graded by the Discoloration Index system (DI). RESULTS: After 3 months, the Test group (n = 13) showed significant reduction in mean PII, GI and percentage of gingival bleeding (GB%), while significant increases in mean DI were observed. The improvement in gingival health was observed at all regions with marked reduction in mean GI (from GI = 1.40 to 1.08) and GB% reduction by 24-52%. The proportion of GI = 2 was also reduced significantly from 50-36%. The Control group (n = 23) also showed a decrease in mean PII but significant increases in the mean GI and GB%. Intergroup comparison showed statistically significant differences between mean GI, percentage of gingival bleeding (GB%) and mean DI for the test and control groups after 3 months of supervised rinsing. However, there were no significant intergroup differences for mean PII. CONCLUSION: In conclusion, there was a significant effect of chlorhexidine on gingivitis, although the effect may be too limited to assure prognostic benefits in the prevention of future disease progression.

The effect of citric acid application on periodontally involved root surfaces. II. An in vitro scanning electron microscopic study.

The in vitro effect of citric acid application on periodontally involved root surfaces was investigated using scanning electron microscopy. Teeth were selected following specific criteria. The specimens were prepared for observation, and the features of the root surface were studied. The results demonstrated that a 3-minute application of citric acid (pH = 1.0) to the root surface after scaling and root planing demineralized the outer root surface, opened the dentinal tubules, and exposed collagen fibers. Scaling and root planing alone left the surface with a smear layer, scattered islands of cementum, and no collagen fibers or exposed dentinal tubules.

A clinical evaluation of the effects of a periodontal scaling gel.

This research evaluated the in vivo effects of a periodontal scaling gel used in routine prophylaxis. Fifteen adult patients with moderate to heavy calculus were selected for full mouth hand scaling and prophylaxis using a split mouth design, employing SofScale Scaling Gel in experimental quadrants. Patients and operators were asked to evaluate differences between control and treated quadrants. The following parameters were evaluated during and after treatment: Gingival effects, tooth sensitivity, ease of calculus removal, and overall patient comfort. In addition pre- and post-treatment tooth surfaces were evaluated with scanning electron microscopy using a replicate technique. No tooth sensitivity or soft tissue irritation was observed in any control or experimental quadrants. Calculus removal was independently judged by operators to be easier in the gel treated quadrants when compared to untreated control quadrants. Scanning electron microscopy revealed cleaner enamel and root surfaces with no obvious morphological changes in mineralized tissues. The results of this study demonstrate the safety of the scaling gel and the increased effectiveness of calculus removal during hand scaling of teeth treated with this gel.