A minimally invasive procedure for esthetic achievement: enamel microabrasion of fluorosis stains

Esthetic alterations (such as fluorosis) that result from intrinsic dental staining in enamel and dentin can be controlled or softened by noninvasive methods such as dental bleaching or enamel microabrasion. Part of the enamel is removed during microabrasion; however, this wear is clinically insignificant and does not harm the dental structure. This article presents a case in which the microabrasion technique was used to remove fluorosis staining. Based on the results of this case report, it can be concluded that this technique is efficient and can be considered a minimally invasive procedure.

Effect of toothpaste containing d-limonene on natural extrinsic smoking stain: a 4-week clinical trial

PURPOSE

To determine whether natural smoking stain could be removed/inhibited effectively by a toothpaste containing 5% d-limonene. For comparison and contrast, the effects of d-limonene on tea stain were also assessed.

METHODS

The design was a randomized controlled double-blind trial with parallel groups. Toothpastes were: A: positive control with perlite whitening formulation; B: A+5% d-limonene; C: D + 5% d-limonene; D: negative control. The extrinsic stains were measured using Lobene Stain Index. Following baseline examination, all subjects were randomly assigned to one of the four toothpaste groups and instructed to brush with the assigned products twice daily. Subjects returned to the clinic after 4-week brushing for stain removal assessment, then all extrinsic stains, plaque and supragingival calculus were removed and use of assigned products was continued for another 4 weeks, and the stain scores were repeated for inhibition assessment.

RESULTS

A total of 408 subjects, 201 with smoking stains and 207 with tea stains, participated in the trial. 5% d-limonene combined with Perlite whitening formulation significantly reduced stain scores both for smoking stain removal and inhibition (P < 0.05). Furthermore, 5% d-limonene alone (in negative formulation) exhibited an additional advantage for smoking stain inhibition (P < 0.05), but the advantage was not found for long-standing smoking stain removal (P > 0.05). The additional advantage of 5% d-limonene was shown neither for removal nor for inhibition in the tea stain study (P > 0.05). All test products were well tolerated over the study period.

In vitro colorimetric evaluation of the efficacy of home bleaching and over-the-counter bleaching products

OBJECTIVE

Various bleaching modalities are now offered to patients, either monitored by the dental office or self-directed, for which relative efficiency is unknown. The aim of this in vitro study was to evaluate the ability of bleaching products and protocols to lighten enamel and dentin.

METHOD AND MATERIALS

Bovine tooth specimens of standardized thickness (2.5 +/- 0.025 mm with similar dentin and enamel thickness) were prepared and stained with whole blood and hemolysate before being submitted to seven supervised or self-directed bleaching regimens: tray-based bleaching using 10% (Opalescence, Ultradent; Nite White, Discus Dental) or light-activated 30% (Metatray, Metatray) carbamide peroxide (CP); 6% (Zoom, Discus Dental) or 9% (TresWhite, Ultradent) hydrogen peroxide (HP); strips (Whitening Strips, Oral B-Rembrandt); and paint-on gel (Paint on Plus, Ivoclar Vivadent) containing 8.1% and 6% HP, respectively. Colorimetric measurements were performed on each specimen side, according to the CIE L*a*b* system, before and after staining, as well as after 5, 10, and the recommended number of bleaching applications.

RESULTS

Color change after recommended number of applications (DEr) varied from 15.72 (Metatray) to 29.67 (Nite White) at enamel and 14.91 (Paint on Plus) to 41.43 (Nite White) at dentin side; Nite White (10% CP) and TresWhite (9% HP) were more effective than Metatray (30% CP) and Paint on Plus (6% HP) after 5 or the recommended number of applications.

CONCLUSION

In this in vitro study based on bovine teeth, tray-based systems produced the faster and better bleaching effect, regardless of the product and concentration used, at both enamel and dentin sides.

Prediction of color change after tooth bleaching using fuzzy logic for Vita Classical shades identification

Tooth bleaching is becoming increasingly popular among patients and dentists since it is a relatively noninvasive approach for whitening and lightening teeth. Instruments and visual assessment with respect to commercial shade guides are currently used to evaluate tooth color. However, the association between these procedures is imprecise and the degree of color change after tooth bleaching is known to vary substantially between studies; there are currently no objective guidelines to predict the effectiveness of a tooth-bleaching treatment. We propose a new methodology based on fuzzy logic as a natural means of representing the imprecision present when modeling the color change produced by a tooth-bleaching treatment on the basis of a tooth's initial chromatic values. This system has the advantage of producing a set of interpretable fuzzy rules that can subsequently be used by scientists and dental practitioners. The fuzzy system obtained has the special characteristic whereby the rule antecedents correspond to prebleaching shades of the well-known Vita commercial shade guide. Additionally, the rule consequents directly correspond with the expected CIELAB postbleaching values for each Vita shade, thanks to a modification of the system's inference structure. Finally, the values of these postbleaching CIELAB coordinates have been associated with Vita shades by evaluating their respective membership functions, thereby approximating which posttreatment Vita shades are to be expected for each prebleaching shade.

Porcelain laminate veneer on a highly discoloured tooth: a case report

Esthetic treatment of a single darkened tooth represents a great challenge to the dental practitioner. The properties of dental ceramic-colour stability, mechanical strength, clinical longevity, esthetic appearance and compatibility with periodontal tissues-make this material a good choice for such treatment. We present a case of restoration of a single, highly darkened anterior tooth with a feldspathic porcelain veneer. Resolution involved preparation of the dental structure guided by orientation grooves and provisional restoration using composite resin, a silicone impression and adhesive luting. Conservative use of porcelain laminate veneers provides satisfactory esthetic outcomes and preserves sound tooth structure. The patient was very satisfied with the result and had no complaints during 2 years of follow-up.

The parallel stratification masking technique: an analytical approach to predictably mask discolored dental substrate

Discolored dental substrates continue to challenge the restorative team when ultraconservative treatment modalities are chosen. An innovative laboratory concept--the parallel stratification masking technique--has been developed in order to achieve maximum preservation of dental hard tissues and predictably accomplish a desirable esthetic outcome. The major advantages of this technique are that the ceramist is able to: a)identify and map the discolored dental substrate, b)predictably mask the discolored dental substrate, and c) assess the appropriate masking efficacy of the fabricated restoration prior to laboratory delivery to the dentist in cases of bonded porcelain restorations.

An effective bleaching technique for non-vital, discoloured teeth in children and adolescents

Discolouration of a permanent incisor may have a significant social impact on children and adolescents. Intervention should be minimally destructive of tooth tissue and should not compromise future restorative options. This paper reviews the technique of inside/outside bleaching, and proposes it as an efficient, effective and acceptable method for use in the compliant younger patient with an unaesthetic non-vital tooth.

Nonvital tooth bleaching with halogen light-activated agents: case reports and discussion

Esthetic dentistry has received increased attention in recent years, as people are more aware of the esthetic appearance of their teeth, including alignment and whiteness. This development, combined with a decrease in the incidence and severity of caries, has directed some clinicians toward conservative and non-invasive treatments such as tooth bleaching. A number of methods for nonvital tooth bleaching are described in the literature; these procedures rely on the bleaching agent used, the agent's concentration, product format, and the source of light activation. This article presents two case reports in which dental bleaching with halogen light-activated agents was used to treat a nonvital discolored incisor. The advantages and disadvantages of the technique are discussed.

Clinical validation and calibration of in vitro peroxide tooth whitening

OBJECTIVE

The purpose of this study was to validate and calibrate an in vitro test method for screening the performance of peroxide-containing toothpastes against actual clinical whitening performance. An additional objective was to estimate the whitening performance of a new peroxide-additive gel using the in vitro methodology.

METHODS

A one-month longitudinal clinical study was performed to provide a benchmark for the in vivo intrinsic whitening performance of a peroxide-containing fluoride toothpaste. An in vitro study was then conducted, using freshly prepared slurries of the same peroxide-containing toothpaste in artificial saliva, to repeatedly treat extracted human teeth with natural intrinsic stain. The effect of cumulative treatment time on whiteness was determined using objective chromometer whiteness measurements (L*, a*, and b*), and more subjective Vita Shade guide (Vitapan) comparisons, and the results were correlated. A non-peroxide fluoride toothpaste was used as a negative control. The peroxide gel additive, combined in a 1:1 ratio with each of two non-peroxide toothpastes and diluted in artificial saliva, was evaluated using the same instrumental and subjective measures for in vitro whitening efficacy. The previously evaluated peroxide toothpaste and one of the non-peroxide toothpastes were used as positive and negative controls, respectively.

RESULTS

In the clinical study, the peroxide-containing toothpaste produced a linear increase in tooth whiteness with time, achieving an approximately two Vita Shade guide improvement in whiteness at the end of four weeks. The same peroxide toothpaste in vitro produced a curvilinear increase in tooth whiteness versus cumulative treatment time, with a two-shade increase being achieved in 116 minutes. The non-peroxide control toothpaste produced less than half a shade guide increase in whiteness within the first 30 minutes, and none thereafter. Both the clinical and in vitro studies indicated that further whitening can be obtained with longer use of the peroxide-containing toothpaste or peroxide-additive gel.

CONCLUSION

Treatment of naturally stained teeth in vitro with the peroxide toothpaste for 116 cumulative minutes produced the same two-shade increase in whiteness as obtained with twice-daily brushing for four weeks in vivo. The peroxide-additive gel, combined with a non-peroxide toothpaste, is projected to provide a similar two-shade increase in whiteness when used twice daily for four weeks. There are indications that greater intrinsic whiteness increase would be achieved with the peroxide toothpaste or with the peroxide-additive gel plus non-peroxide toothpaste with more extended regular twice-daily use in vivo.

A rationale for the use of high-powered magnification or microscopes in general dentistry

This article argues that high-powered magnification (4x-6x or more) provides substantially more visual information for diagnosing and treating dental pathology compared to the use of unaided vision or entry-level 2.5x magnification. In all phases of general dentistry, the increased visual detail provided by high magnification reduces ambiguity in diagnosis and treatment decision-making, increases control in treatment implementation, allows a dentist to produce more ergonomic restorations that are less prone to recurrent decay, and arguably improves clinical outcomes compared to work performed with unaided vision. High magnification enhances a dentist's ability to diagnose caries and cracks in teeth, distinguish between different colors intraorally, detect the interfaces between different surfaces and materials, detect microscopic interferences in fixed and removable metal frameworks, adjust occlusal prematurities, and polish restorations. This article explains specific general dental applications for high-powered magnification in restorative dentistry, fixed and removable prosthodontics, endodontics, pediatric dentistry, periodontics, and oral surgery.

Clinical assessment of extrinsic stain removal efficacy with a new Pulsonic toothbrush

OBJECTIVE

To assess the extrinsic stain removal benefit of two different power toothbrushes: an experimental Oral-B Pulsonic rechargeable toothbrush and a positive control Sonicare FlexCare toothbrush.

METHODS

This was a randomized, positive-controlled, examiner-blind, two-treatment, parallel group, two-week study. A Lobene stain index was performed at baseline on the facial surfaces of the anterior teeth. Subjects were randomized to one of two treatment groups: Pulsonic or FlexCare. Both groups were assigned the same fluoride dentifrice, and were instructed to brush their teeth twice per day for two minutes with the assigned toothbrush and dentifrice in front of a mirror. A further Lobene stain index was performed following two weeks of brushing.

RESULTS

A highly significant reduction (p < 0.001) in mean Lobene composite scores after two weeks was found for both the Pulsonic treatment group and the FlexCare treatment group (median reduction of 94.4% and 90.7%, respectively). Both treatment groups also showed a highly significant (p < 0.001) reduction in extent and intensity scores. No significant treatment group differences were seen in the reduction in mean Lobene scores (p > 0.1).

CONCLUSION

Both the experimental Pulsonic and the positive control FlexCare power toothbrushes showed highly effective stain removal efficacy relative to baseline following two weeks of brushing. Stain removal efficacy did not differ significantly between brushes.

["Power bleaching" with the KTP laser]

The most important constituent of the bleaching process is the hydrogen peroxyde. The bleaching effect is the result of a change in the chemical structure of organic molecules in the teeth. Different bleaching techniques are described on the basis of the concentration of the hydrogen peroxyde used and on the basis of the different methods of application. It has been demonstrated that a faster change in colour can be obtained when bleaching is performed in combination with a light source i.e. power bleaching aiming for a more in depth change of colour. Different investigations have demonstrated that negative effects associated with bleaching agents are seen earlier when light sources have been used as accelerators. So, light activation may not lead to 'heating of the pulp'. Different types of laser bleaching have been described, though, not all of them will lead to the desired result. There is only one exception at present and this is the KTP-laser bleaching with the Smart Bleach gel. The specific laser-tissue interaction is the result of different activation processes of the hydrogen peroxyde in the gel: as a result of the interaction with the laser a photocatalytic effect is induced (i.e. the activation of the gel by means of light--this is also referred to as a photochemical reaction), a limited photothermal effect (light absorption may result in a certain heating of the gel). The light activated gel also has an alkaline pH, which favours the ionisation of the hydrogen peroxyde into perhydroxyl ions (these are the most reactive free radicals). It is also possible to directly cut the tetracycline molecules (a good absorption of light by the tetracycline molecules at 532 nm). This will result in better decolouration of tetracycline stained teeth. This last process is described as direct photobleaching. It also needs to be emphasized that bleaching with a laser can only be performed by a dentist who has acquired a substantial knowledge on laser-tissue interaction and laser physics, and who follows accurately the requested bleaching procedure. Furthermore, whatever the opinion might be, tooth bleaching is a medical dental procedure on biologic tissues and hence this procedure can only by dentists.

Co-existence of crowns and veneers in the anterior dentition: case report

Crowns and veneers provide distinct treatment strategies with different outcomes in terms of tissue conservation, periodontal distress and esthetic result. It is not always clear where a crown or veneer is indicated, but in the last two decades, adhesive technology, conservative approaches and esthetic demands have increased clinical indications for porcelain veneers in restorative dentistry. A combination of veneers and crowns may be required, especially in the anterior region. It may be desirable to reinforce some teeth and preserve tissue on others. Problems can arise with the esthetic integration of both types of restoration, owing to their inherent mechanical and optical properties. Several clinical and laboratory techniques can be applied for a successful combination. In this article the authors describe the procedures and difficulties in treating a case with such needs.

The effect of a mild increase in temperature on tooth bleaching

OBJECTIVE

To evaluate the effect of temperature on external tooth bleaching.

METHOD AND MATERIALS

Human molars and premolars were internally stained and assessed using a standardized tea solution. The mesial aspects of the teeth were assigned to the treatment group (bleaching at 45 degrees C), and the distal aspects of the teeth were assigned to the control group (bleaching at 37 degrees C). An electronic chromometer with a tristimulus color analyzer was used to measure color change. The mean changes in the values of L*, a*, and b* from baseline to posttreatment were recorded, as were the overall color differences of the specimens in each group (DeltaE*).

RESULTS

Increasing the temperature to 45 degrees C significantly (P < .05) increased the bleaching efficacy and reduced the time needed to gain a lighter tooth shade.

CONCLUSION

A controlled increase in the temperature of the bleaching agent might be useful in achieving better tooth bleaching in a shorter period of time.