The relationship of tooth shade and skin tone and its influence on the smile attractiveness.

OBJECTIVE: The purpose of this clinical study was to determine if skin tone and tooth color had the same influence on smile attractiveness. MATERIALS AND METHODS: A woman's smile photograph was digitally manipulated to create a range of images with varying colors. The skin shade was modified to create four tones (p1: light, p2: light medium, p3: medium dark, p4: dark) using the L'Oreal True Illusion shade as a guide. The tooth shade was modified in four different tones: A1, A2, A3, A4 using the VITAPAN Classical shade guide to produce 16 images. A sample of 328 participants rated each image for attractiveness by means of a visual analog scale (VAS). Comparison among groups was performed with a 2-way ANOVA adjusted for multiple comparisons with the Bonferroni test (α = .05). RESULTS: Image (p3-a1) showed the highest VAS values, while image (p1-a4) obtained the lowest, (Bonferroni Test: a1 vs a2, a3, a4 P < .001; p3 vs p1, p2, p4 P < .001). Analysis performed for age, sex, level of education, and laypeople/dentists were not statistically significant (P > .05). CONCLUSIONS: Variations in tooth and skin tone can significantly influence the perception of smile attractiveness. In the tested conditions, a brighter tooth shade significantly affected the attractiveness of the smile independently from skin tone. CLINICAL SIGNIFICANCE: Understanding patient and dentist perception of the attractiveness of a smile with the important role-played by skin tone, may help clinicians to better identify teeth shade, helping delivery of tailored prostheses and esthetic restorations.

Single tooth anesthesia versus conventional anesthesia: a cross-over study.

OBJECTIVES: The aim of the present study was to compare an electronic device, the Wand Injection System (Milestone Scientific Livingstone), with conventional anesthesia in terms of the following: pain sensation during anesthetic injection; effectiveness in achieving adequate anesthesia for a complete painless dental treatment; post-operative discomfort; and patient's anxiety toward dental treatment. MATERIALS AND METHODS: Eighty adults from 18 to 70 years were enrolled in this cross-over study. Each patient served as his/her own control being subject to two anesthesia techniques: conventional and Single Tooth Anesthesia (STA) performed with the Wand. A split-mouth design was adopted in which each tooth undergoing conservative restorative or endodontic treatment received anesthesia with both techniques at 1-week interval. Before anesthetic administration, the patients' anxiety levels were determined. Physiological parameteres were measured before, during, and after the two injection procedures, and the Visual Analogue Scale (VAS) was used to assess pain of injection, discomfort, and anesthetic efficacy. Differences in assessment of pain's injection, discomfort, anesthetic efficacy, vital parameters (heart rate, blood pressure, and oxygen saturation), and state anxiety levels were analyzed using Student's t test (p value < 0.001). RESULTS: The mean injection pain and post-operative discomfort ratings with Wand were lower than those with conventional syringe (p = 0.022 and p < 0.001, respectively). No differences were found in the assessment of anesthetic efficacy. Blood pressure and heart rate mean values were lower during the anesthesia performed with the Wand than with the conventional syringe (p < 0.001). The anxiety level was higher during the first appointment, independently from the device used for the injections. CONCLUSION: The STA technique resulted in lower pain, discomfort, and lower intensity of physiological parameters. CLINICAL RELEVANCE: Single Tooth Anesthesia could be an efficacious alternative to conventional procedures.

Accuracy of three electronic apex locators compared with digital radiography: an ex vivo study.

INTRODUCTION: This study compared (1) the accuracy of three different electronic apex locators (EALs) in detecting the apical foramen ex vivo under clinical conditions; (2) the accuracy of digital radiography and EALs in determining the working length (WL) with visible control under a microscope; and (3) the precision of #10, #15, and #20 K-files in electronic measurements. METHODS: The length of 101 extracted human teeth was measured with three different EALs (Endex [Osada Electric Co, Tokyo, Japan], ProPex II [Dentsply-Maillefer, Ballaigues, Switzerland], and Root ZX [J. Morita Co, Tustin, CA]), with radio videography (RVG) and compared with the actual length. An endodontic training kit (Pro-Train; Simit Dental, Mantova, Italy) was used during the experimental procedures. RESULTS: Statistical analysis showed that Endex and ProPex II were more accurate than Root ZX in determining the WL. The paired sample t test showed no statistically significant difference between the accuracy of the two radiographic planes examined. The t test showed no significant difference between the three different K-file sizes measurements. CONCLUSIONS: Endex and ProPex II were more accurate than Root ZX in determining the actual WL. Instrument sizes of hand files did not affect the accuracy of EALs. EALs showed to be more accurate in determining the WL than RVG.