The effect of gum chewing on sensitivity associated with in-office whitening procedures.

OBJECTIVES: Tooth sensitivity is the most common side effect of in-office tooth-whitening procedures. The purpose of this study was to determine whether chewing gum containing 0.6% casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) before tooth whitening would reduce tooth sensitivity during an in-office whitening procedure. METHODS: Thirty participants were enrolled and randomized into three groups as follows: group 1 was instructed to not chew gum during the study period; group 2 chewed five pieces of gum (with 0.6% CPP-ACP) for 10 min each day 1 week before whitening; and group 3 chewed five pieces of gum (without CPP-ACP) for 10 min each day 1 week before whitening. All participants had their teeth whitened with a 30% hydrogen peroxide in-office whitening procedure. The participants' shades of teeth were evaluated with a spectrophotometer four times during the study: at the initial screening visit, immediately before whitening, immediately after whitening and 1 week after whitening. Participants' sensitivity levels were evaluated each time the shades were evaluated and additionally at 24 h after whitening using a 100-mm visual analogue scale. RESULTS: Thirty participants were enrolled in the study. The average shade change was -2.27 (± 2.07). The average sensitivity for all groups at visit 1 was 5.12 (± 13.94). The average sensitivity for all groups after whitening was 19.81 (± 13.95). There were significant differences in sensitivity between groups 2 and 3 (P = 0.02), but neither group was significantly different from the control group (P = 0.86, P = 0.07). CONCLUSIONS: Chewing gum before whitening, including gum with CPP-ACP, did not reduce sensitivity during in-office whitening procedures.

The effect of light on tooth whitening: a split-mouth design.

OBJECTIVES: Conflicting research exists on the effect that various lights have on in-office tooth whitening. The aim of this study was to determine whether a sodium arc bulb lamp used with 25% hydrogen peroxide shows significant differences in shade using a split-mouth design. METHODS: Forty-nine subjects meeting study criteria had anterior teeth whitened with a 25% hydrogen peroxide in-office whitening system. The light was used on a randomly selected right or left half of the mouth. The opposing side was whitening only with gel. Shades were recorded using a spectrophotometer before, immediately after, 1 and 2 weeks post-whitening. Sensitivity was also recorded using a visual analogue scale. Values were analysed with a Friedman test with a stepdown Bonferroni adjustment for multiple comparisons. RESULTS: All teeth increased in lightness after whitening procedures. The only significant differences between use of the light and without use of the light were on the maxillary arch 1 week after whitening (P = 0.010). Sensitivity was greatest immediately after whitening but subsided within 1 week of whitening. CONCLUSIONS: The use of a sodium arc bulb lamp with 25% hydrogen peroxide in-office whitening produces better results on maxillary teeth up to 1 week after whitening is completed. Subjects could not distinguish differences on each side of the mouth.

Visual Ability Score -- a new method to analyze ability in visually impaired children.

PURPOSE: We analyzed the correlation between the Preferential Looking (PL) acuities and the Visual Ability Scores (VAS) of 600 patients (many with severe retinopathy of prematurity) to determine their ability to perform various activities within the daily environment. METHODS: Visual acuity was measured by PL. Sixteen visual activities within the environment were analyzed. The VAS (range, 1-16) were calculated from the results of each activity and correlated with PL acuity. RESULTS: The PL acuities of the 600 patients ranged from 20/20 (1.0) to <20/3200 (0.006) [mean, 20/337(006)]. The VAS ranged from 1 to 16 points (mean, 10.65; SD, +/-4.80) and showed a high correlation with the PL acuities (r=0.917, p=0.0001). CONCLUSIONS: In addition to PL vision testing, analyzing the environmental visual behavior of young, severely visually impaired patients is important to accurately evaluate visual abilities. We found the VAS to be an important aid for low-vision specialists, especially for those with no access to a vision evaluation system such as PL.

Correlating preferential looking visual acuity and visual behavior in severely visually handicapped children.

We developed a series of questions that reflects the functional abilities of severely visually handicapped children. The study population comprised 100 patients aged 30 to 60 months (mean 43.23), mostly afflicted with retinopathy of prematurity. Visual acuity was measured by preferential looking. Preferential looking acuities of the patients ranged from 20/25 (0.8) to 20/6400 (0.003) (mean 20/470 (0.04)). Ten activities were analyzed and correlated with preferential looking acuity. Among the selected visual activities, when children are not interested in television (p = 0.0001), toys (other than those that make sounds (p = 0.0001), and people (p = 0.001)), their preferential looking acuities were very low. For example, 73 out of 100 patients who were visually interested in television had preferential looking acuities (mean 20/245 (0.082)) that were significantly higher (p = 0.001) than 21 patients not interested in television (mean 20/2806 (0.007)). Patients with nystagmus (n = 79) had significantly lower preferential looking acuities (p = 0.0001) (mean 20/1114 (0.018)) than patients with no nystagmus (mean 20/57 (0.35)). When evaluating visual function in young, severely visually impaired patients, in addition to preferential looking testing, analyzing visual behavior within the environment is important to accurately evaluate their remaining visual abilities.