Aesthetic Outcomes of Single Tooth Implant-supported Restorations in the Anterior Maxilla With Either White Zirconia or Fluorescent White Zirconia Abutments

Inclusion Criteria:- Systemically and periodontally healthy subjects,18 years of age with good plaque control (less than 25% PlI) or subjects with a healthy periodontium if selected from a periodontal maintenance program. * The presence of a single tooth gap in the anterior maxilla (from tooth number 1.5-2.5) with the presence of natural adjacent dentition. A minimum 4 months healing was required if the tooth had been recently extracted. * The presence of ≥ 2 mm of keratinized tissue in the alveolar ridge and enough bone availability to insert a Tapered internal implant (BioHorizons, Birmingham, EEUU) without the need of bone augmentation (minimum of 5.5 mm in width and 9 mm in height). * The opposing dentition should be stable (without removable appliances) and subjects with bruxism were excluded. Exclusion Criteria: * In patients with a history of periodontitis, if periodontitis re-occurred (clinical attachment loss ≥ 2 mm), they will be excluded from the study and receive periodontal therapy. * During implant placement, the selected subject will be excluded if implants were not positioned in appropriate prosthetic guided positions. Implants needing any hard tissue augmentation will be excluded before the surgery, however if during the surgery any of this procedure is needed due to unforeseen, the patient will also be excluded from the study "a posteriori". * Pregnant women at any time of the study will be excluded. * Inadequate vestibular depth to place the Spect…