International Journal of Esthetic Dentistry (EN), 04/2012

In this two-part case presentation, the benchmarks of our treatment planning principles are briefly explained and their application is discussed in the case of a 35-year old patient with multiple failing restorations and an esthetic complaint regarding the maxillary anterior teeth. In this first part, the four principles are proposed, the patient's main problems are presented and three treatment options are discussed. In the second part, the treatment choice will be disclosed as well as the decisionmaking process, the respective diagnostic procedures involved, and finally the sequential treatment. The aim of these articles is to stimulate the debate and to promote therapeutic choices that take into account evolution of contemporary dental medicine.

When replacing a missing tooth in the esthetic zone, the implant supported single tooth restoration can result in a very natural and pleasing solution for the patient, being also a conservative procedure that preserves the adjacent remaining dentition. Immediate implant placement with an immediate provisional crown can avoid stressful and uncomfortable healing time for the patient who no longer has to wear an interim removable appliance. In selected clinical situations, excellent tooth esthetics for implant supported single tooth restorations can be achieved by using the natural extracted tooth as both provisional and final restoration. No longterm data is available today as far as the survival rate of such restorations and the predictability of such a treatment modality. This case report describes a technique for utilizing the patient's extracted tooth for the fabrication of an inconspicuous final anterior restoration, reporting a 5-year follow-up.

The objective of this narrative overview is to discuss several in vitro and in vivo studies regarding the performance of one-piece zirconia implants in combination with the description of two clinical scenarios where zirconia implant prototypes were utilized with emphasis on the possible scientific and clinical concerns that may affect the functional, biological and esthetic long-term outcomes.

Objective: The aim of this study was to identify the presence of monoclinic zirconia phase (m-ZrO2) in 5 computeraided design/computer-assisted manufacture zirconia systems composed of yttria-stabilized tetragonal zirconia polycrystals (Y-TZP). Materials and methods: Three-unit fixedpartial dentures were prepared from Cercon (CR); Lava (LW); Zenotec Zr Bridge (WD); In-Ceram YZ (YZ); and IPS e-max ZirCAD (ZC), all milled in a pre-sintered stage and then fully sintered according to the manufacturers' instructions. Raman spectroscopy was used to identify and map the distribution of the m-ZrO2 phase at cervical crown margins, pontic and connector regions. Three sets of data were obtained from each material (n = 2) and the percentage volume (%Vm) of the m-ZrO2 phase was calculated per region. Statistical analysis was performed by two-way analysis of variance and Tukey test (a = 0.05). Results: The m-ZrO2 phase was detected in all the specimens, with the highest intensity located at the crown margins. WD showed the lowest %Vm content (0- 3.14%), followed by LW (10.26-12.39%), CR (11.72-13.19%), ZC (11.13-14.10%) and YZ (12.15-14.99%). No statistically significant difference was found among LW, CR, ZC, YZ per region. Within each material group, significant differences were found between margin-pontic/connector (WD, YZ), margin-connector (CR, ZC) and margin-pontic (LW). Significance: The Y-TZP destabilizing m-ZrO2 phase was identified in all the fully sintered frameworks tested, with the highest %Vm located at the margins. The extent to which the presence of this phase may be implicated with zirconia low temperature degradation or porcelain to zirconia bonding is unknown.

Introduction: The development of countless types and trends of high viscosite and flowable composite resins, with different physical and chemical properties applicable to their broad use in dental clinics calls for further studies regarding their radiopacity level. Purpose of the study: The aim of this study was to evaluate the radiopacity levels of high viscosity and the flowable composite resins, using digital imaging. Materials and methods: 96 composite resin discs 5 mm in diameter and 3 mm thick were radiographed and analyzed. The image acquisition system used was the Digora® Phosphor Storage System and the images were analyzed with the Digora software for Windows. The exposure conditions were: 70 kVp, 8 mA, and 0.2 s. The focal distance was 40 cm. The image densities were obtained with the pixel values of the materials in the digital image. Results: Most of the high viscosity composite resins presented higher radiopacity levels than the flowable composite resins, with statistically significant differences between the trends and groups analyzed (P 0.05). Conclusions: Among the high viscosity composite resins, Tetric®Ceram presented the highest radiopacity levels and Glacier® presented the lowest. Among the flowable composite resins, Tetric®Flow presented the highest radiopacity levels and Wave® presented the lowest.

External beauty is a complex construct that influences lives and may be impacted by dentists. Beauty is not easily quantified, but one cited anthropometric of beauty is the ratio phi, the number 1.618033(...). This study examined phi as a measure of female frontal facial beauty in classic Western art, using pre- Renaissance (N = 30), and Renaissance (N = 30) artwork. Four horizontal and five vertical ratios were determined in the works of art, which were then compared with the phi ratio. All horizontal ratios for both pre-Renaissance and Renaissance artwork were similar to each other, but did not contain the phi ratio (P 0.001). Nevertheless, all vertical ratios for pre-Renaissance and Renaissance art-work did contain the phi ratio within their confidence intervals with the exception of the vertical ratio, "intereye point to soft tissue menton/ intereye point to stomion", that was found to be less than phi in the Renaissance group. The study provides evidence of the presence of the phi ratio in vertical aspect of females in artwork from pre-Renaissance through the Renaissance demonstrating consistent temporal preferences. Therefore, the phi ratio seems to be an important consideration in altering vertical facial dimensions in full mouth rehabilitation and reconstructive orthognathic surgery involving females.

Introduction: Each facial feature might affect the perception of the balance of the other features so the whole of the face must be considered in facial evaluation. There are no studies that have examined the effect of forehead and neck position on profile esthetics. The objective of this study was to evaluate the effects of forehead and neck positions on profile esthetics judged by laypeople, dental students and art students. Materials and methods: A straight silhouette (black right-facing profile in white background) was digitally manipulated to make variations of profiles. The positions of all compartments of face were similar except for anteroposterior position of forehead and neck. The 310 raters (100 dental students, 100 art students and 110 laypeople) were asked to rate profiles with a Likert scale. The nonparametric Mann-Whitney test, chisquare tests, Spearman rank correlation coefficients, one-way analysis of variance (ANOVA) and Kruskal-Wallis analyses were used in data analysis. Results: The scores given to profiles with straight, retruded and protruded necks and foreheads were significantly different. (P 0.05). In three groups, the most and least attractive profiles judged by raters were comparable (P > 0.05). Conclusion: This study showed that the position of the forehead and the neck has an effect on the beauty of profile silhouettes and this effect is so noticeable that all of the raters could perceive the differences. It is necessary to evaluate the whole of the face, including the forehead and neck, in a facial evaluation.