Digital Smile Design and mock-up technique in esthetic crown lengthening: 2-year follow-up of six cases.

The present case series aimed to evaluate the use of a Digital Smile Design (DSD) and mock-up technique for esthetic crown lengthening (ECL) surgery in six clinical cases with a 2-year follow-up. Six nonsmoker patients (five females, one male; aged 22 to 32 years), periodontally and systemically healthy, with inadequate tooth width/height ratio proportions associated with a gingival misalignment in the anterior maxilla were included. The DSDs were created using PowerPoint for all patients to evaluate gingival level and tooth form/contour. A wax-up and mock-up were created based on the DSD measurements. ECL surgeries were performed in all cases using the mock-up technique to determine the final gingival margin position and the amount of bone resection needed. A mock-up to bone crest distance of 3 mm was obtained in all cases. Using patient photographs, comparisons were made between the dental crown length (DCL) measurements obtained before the surgical procedure (baseline; T0), on the DSD template immediately postoperatively (IPO; T1), and at the 2-year follow-up (T2). A DCL augmentation of 1.16 ± 0.68 mm was obtained at T1, with an augmentation of 1.03 ± 0.73 mm at T2. Moreover, a minimal difference of 0.34 ± 0.74 mm between the DCL planned in the DSD template and the DCL obtained IPO was observed. In conclusion, the ECL procedure based on the DSD concept and mock-up technique proposed in this cases series was a predictable protocol for smile disharmony treatment in all the patients.

Three-dimensional printing and in vitro evaluation of poly(3-hydroxybutyrate) scaffolds functionalized with osteogenic growth peptide for tissue engineering.

Poly(3-hydroxybutyrate) (PHB) is a biodegradable and thermoprocessable biopolymer, making it a promising candidate for applications in tissue engineering. In the present study a structural characterization and in vitro evaluation were performed on PHB scaffolds produced by additive manufacturing via selective laser sintering (SLS), followed by post-printing functionalization with osteogenic growth peptide (OGP) and its C-terminal sequence OGP(10-14). The PHB scaffolds were characterized, including their morphology, porosity, thermal and mechanical properties, moreover OGP release. The results showed that SLS technology allowed the sintering of the PHB scaffolds with a hierarchical structure with interconnected pores and intrinsic porosity (porosity of 55.8 ±â€¯0.7% and pore size in the 500-700 µm range), and good mechanical properties. Furthermore, the SLS technology did not change thermal properties of PHB polymer. The OGP release profile showed that PHB scaffold promoted a controlled release above 72 h. In vitro assays using rat bone marrow stem cells showed good cell viability/proliferation in all the PHB scaffolds. Additionally, SEM images suggested advanced morphological differentiation in the groups containing osteogenic growth peptide. The overall results demonstrated that PHB biopolymer is potential candidate for 3D printing via SLS technology, moreover the OGP-containing PHB scaffolds showed ability to sustain cell growth to support tissue formation thereby might be considered for tissue-engineering applications.