IntroductionThe demand for esthetic dentistry procedures has significantly increased over the past few decades due to factors such as the influence of social media, greater emphasis on appearance and self-image, and advancements in less-invasive and more affordable cosmetic treatments.1,2 It has been demonstrated that good oral health—including an attractive smile can significantly affect self-confidence and sexual well-being in young adults, ultimately impacting overall quality of life.3 One of the primary sources of dissatisfaction with a person’s smile is related to the shade, size, arrangement, and position of the teeth.4These concerns can often be addressed through orthodontic and/or restorative dental treatments.In restorative dentistry, all-ceramic restorations have gained popularity and are increasingly becoming the first choice for restoring the anterior dentition, replacing traditional porcelain-fused-to-metal (PFM) restorations. All-ceramic options eliminate the grayish discoloration often seen in metal-ceramic restorations.5 Studies have reported that the top three material choices for anterior restorations are lithium disilicate, followed by layered zirconia and leucite-reinforced ceramics.6 All-ceramic crowns in the anterior region have demonstrated excellent long-term success and low failure rates,7 while all-ceramic veneer restorations in the esthetic zone have shown survival rates exceeding 90% over periods longer than 10 years.8Ceramic veneer restorations have been shown to successfully fulfill patients’ esthetic demands.9 However, they pose a challenge when teeth present stains, because a ceramic veneer may not be able to block out the dark background.10 In some clinical situations, tooth whitening can be performed before veneer placement, but whitening does not always achieve the desired shade. Traditionally, full‐coverage crowns were recommended when a dark background is present.11,12 More recently, novel approaches have been suggested, such as placing an all‐ceramic core to mask the stain, followed by a veneer restoration.13The combination of a ceramic core and veneer may offer clinicians a way to successfully mask dark tooth shade and enable dental technicians to fabricate highly esthetic restorations. Unfortunately, clinical reports in the literature are very limited, and the procedural steps can be confusing for less experienced clinicians. Therefore, this report presents a case in which a severely internally stained maxillary right central incisor was treated with a ceramic core and lithium disilicate veneer to meet the patient’s esthetic expectations. The multidisciplinary treatment also included gingivectomy to improve gingival architecture of that incisor, and a single ceramic veneer on the left central incisor to address incisal and facial wear.

IntroductionDental care in the esthetic zone is usually a challenging situation for the clinician because small imperfections are easily noticeable by the patient. The aesthetic zone usually extends from maxillary right canine to maxillary left canine; however, some patients may present a wide smile displaying the gingival tissues and extending up to the premolars or molar teeth which increases the complexity of achieving optimal esthetic results.1,2 Furthermore, it has been demonstrated that as the person ages, the mandibular tooth display may increase significantly.3 In order to have insightful assessment, clinician must evaluate several factors, such as vertical position, ratio and symmetry and spaces, midline and tooth angulation in anterior dentition, tooth color, gingival architecture and exposure and buccal corridors.4Minimally invasive restoration is always recommended because it provides a re-treatment option to the tooth in case of secondary caries or any type of injury.5,6 Veneer preparations are always encouraged instead of traditional full coverage preparations because it has been demonstrated that veneers only require the removal of 3 to 30% of tooth structure in comparison to the 63 to 75% of traditional full coverage crowns.7 Moreover, studies and authors agree that the greater the amount of tooth structure the higher the survival rate of the tooth.8,9 Therefore, conservative tooth structures aiming to only remove the caries and to create the necessary space for the restorative material is encouraged.Tooth reduction guides facilitate accurate removal of tooth structure to create the desired contours of the preparation. Traditional tooth reduction guides can be fabricated with vacuum-formed thermoplastic sheet, polyvinyl siloxane impression material, acrylic resin, and casted metal.10,11 Several case reports in the literature have shown that the traditional tooth reduction guides facilitate to obtain ideal preparations and the esthetic results fully satisfy patients’ esthetic demands.12-15 Clearly, experienced clinicians may not need the aid of any type of reduction guide, but it is always encouraged specially for novel clinicians.With the advent of novel digital workflows, clinician now can digitally design interim and final restorations, and other oral devices, such as occlusal guards and surgical guides.16-17 The accuracy for 3D printed devices such as restorations, diagnostic models, and surgical guides has been reported to be clinically acceptable; therefore, clinicians have increased their usage for the daily practice.18-20 Unfortunately, the literature offers very limited case reports displaying the steps for designing and 3D printing tooth reduction guides for anterior dentition. Therefore, the aim of this clinical report is to display the digital workflow for minimally invasive preparations for veneers and crowns in the esthetic zone accomplished with a 3D printed tooth reduction guide, followed by ceramic restorations that meet esthetic demands. The transparency of the 3D-printed guide material also allows for visibility, ensuring precise preparation while preserving more of the natural tooth.