Effect of Miswak Derivatives on Color Changes and Mechanical Properties of Polymer-Based Computer-Aided Design and Computer-Aided Manufactured (CAD/CAM) Dental Ceramic Materials.

BACKGROUND Miswak is a form of chewing stick used to clean teeth in different parts of the world, including Saudi Arabia. We present a description of the effects of miswak derivatives, namely toothpaste, mouthwash, and brushing sticks, on the mean color changes (DE00), compressive fracture resistance values, and fracture modes of polymer-based computer-aided design (CAD) and computer-aided manufactured (CAM) prosthetic materials. MATERIAL AND METHODS Eighty-one rectangular-shaped samples were prepared from lithium disilicate glass-ceramic (IPS e.max CAD), zirconia-reinforced lithium silicate (Vita Suprinity), and monochromatic tooth-colored feldspar (Vitablocs Mark II) CAD/CAM ceramics. The color parameters were recorded using spectrophotometer before and after exposing the specimens to the different miswak oral hygiene derivatives for 15 days. Compressive fracture resistance values and fracture types were also assessed, and statistical analysis was performed. RESULTS Vita Suprinity and Vitablocs Mark II miswak sticks had the highest ΔE00 values. Moreover, miswak mouthwash had the lowest ΔE00 values, with significant differences among groups. IPS e.max CAD miswak sticks had the highest mean values of compressive fracture. Vitablocs Mark II had the lowest values for mouthwash and toothpaste. Significant differences were found within the IPS e.max CAD group. Reparable fractures were found in IPS e.max CAD, while semi-reparable fractures were seen in other groups. CONCLUSIONS Most ΔE00 values were within the acceptable clinical range, with IPS e.max CAD showing superior color stability. The mouthwash group showed minimal ΔE00. IPS e.max CAD had the highest mean compressive fracture resistance values with reparable fracture types.

Clinical and Radiographical Measurements of Supraeruption and Occlusal Interferences in Unopposed Posterior Teeth.

AIMS AND OBJECTIVES: This study compared the supraeruption of teeth for study casts (SCs) and panoramic radiographs (PRs) and its relation to tooth type, arch, facial sides, presence of occlusal interferences, and type of tooth movements. MATERIALS AND METHODS: A total of 65 patients with their SCs and PRs were recruited. Supraerupted tooth type, arches, sides involved, and the presence of occlusal interferences were recorded. The SCs for supraerupted teeth were photographed, and supraeruption from PRs was recorded from the patients' files. The values were transferred to a software program and assessed. RESULTS: The highest frequency was observed among the younger-age group and molars in both arches. Working side (WS) and retruded cuspal position (RCP) interferences were recorded the highest. Supraeruption values of 0.7-1.2 mm accounted for 47.5% (38) of the total. Tilting and tipping of teeth were the highest, followed by buccolingual displacement. Kappa tests showed good intraexaminer reliability and Bland-Altman plot showed 95% confidence interval band. CONCLUSIONS: No significant differences were observed in the supraeruption values between the type of tooth among different subgroups of SCs and PRs. Significant differences were recorded between the types and sites of teeth, with a higher ratio observed in molar teeth, mandibular arch, and young age group. RCP and WS were the most recorded occlusal interferences and buccolingual displacement, and tilting and tipping were the most noticeable occlusal tooth movements. CLINICAL SIGNIFICANCE: Diagnosis and measurements of supraeruption are essential, useful, and significant steps before treatments for replacement of missing tooth/teeth as well as corrections of occlusal interferences during different mandibular movements.