Clinical Outcomes of Biologically Oriented Preparation Technique

The plaque index will be measured at the buccal, lingual, mesial, and distal sites of each included tooth, according to Löe and Silness, 1963

The gingival index will be measured at the buccal, lingual, mesial, and distal sites of each included tooth according to Silness and Löe, 1964

A UNC periodontal probe will be used to measure the probing depth at the buccal, lingual, mesial, and distal sites of each included tooth.

This variable will be measured at the buccal, lingual, mesial, and distal sites of each included tooth, recorded simultaneously with probing depth, according to Ainamo and Bay, 1975

The gingival marginal stability at the buccal site will be measured using a UNC periodontal probe and a transparent jig to measure the distance between a reference point on the jig and the free gingival margin.

The free gingiva thickness will be measured at the buccal site using a transparent jig with a reference point on the marginal gingiva, a 15-size spreader with a rubber stopper, and a millimetric ruler

The internal and marginal adaptation will be dong using the replica technique. It will be carried out after clinical assessment and cementation of all crowns. An in vitro study utilizing an optical microscope with a micron-graded ruler will be implemented.

The functional and mechanical complications will be appraised. The existence of cracks, chipping, and/ or fracture of crowns and their size if exist according to FDI criteria (Hickel et al., 2010) will be evaluated.

The secondary caries status will be assessed according to Cvar and Ryge, 2005. The presence or absence of caries at the cervical margins of the abutments will be recorded. Other biological complications, such as abutment fracture, root fracture, and/ or pulpitis will be reported, too

The marginal adaptation after crown cementation will be clinically evaluated using a sharp dental probe, according to Cvar and Ryge, 2005, at each follow-up appointment.

The level of color matching will be assessed according to Cvar and Ryge (2005). To measure this outcome, color matching with adjacent teeth, slight mismatching, or major mismatching of color and/or translucency will be reported.

The clinical success status will be assessed according to Walton, 2002. This outcome will be evaluated in case any patient cannot attend the follow-up visits during the trial for any reason. Thus, success might be evaluated indirectly by a phone call if possible.

Patients' satisfaction will be assessed according to FDI criteria (Hickel et al., 2010). This outcome will report the level of patient satisfaction functionally and aesthetically. Complete satisfaction, light criticism, major criticism, and entirely dissatisfaction are the levels of the patient's view that will be described.