###### Abstract  
(1) Background: Dental glass-ceramics shrink during crystallization, complicating restoration manufacturing. Thermo-pressure molding was introduced to address this, with lithium disilicate crystals providing high strength. Residual tensile stresses can influence the chipping strength of single tooth crowns. (2) Methods: Insync dentine was layered onto three lithia-based disilicate core ceramics (Amber Press, IPS e.max Press) for microtesile bond strength tests. The Vickers test assessed the residual tensile stress and interfacial bonding. Porcelain-veneered posterior ceramic crowns were fabricated and subjected to axial loading, measuring fracture loads (three per group). (3) Results: A chemical bonding layer formed at the interface, which was thicker in the Insync-IPS e.max Press and increased with more firings. The ultimate tensile bond strength was 28.5 MPa for the four-times-fired Insync-Amber Press, similar to the twice-fired Insync-IPS e.max Press. No residual tensile stress was found in the Insync-Amber Press; the Insync-IPS e.max Press showed crack growth within 250 \(\upmu\)m of the bonded interface. The average fracture resistance was twice as high for the Insync-Amber Press. (4) Conclusions: The Insync-Amber Press exhibited better thermal harmony with no crack growth, while the IPS e.max Press showed crack growth due to residual tensile stress. Insync-Amber Press posterior ceramic crowns had significantly greater fracture resistance than Insync-IPS e.max Press crowns. v enering porcelain; disilicate core ceramic; dental ceramic crown; fracture resistance  
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precise manufacturing, low porosity, excellent marginal adaptation, and higher strength and Weibull coefficient compared to conventional sintering methods [3]. Glass-ceramic materials utilized in heat-pressed methods include leucite, apatite, and lithium disilicate crystals. Although materials containing precipitated leucite and apatite crystals provide excellent esthetics, they exhibit lower fracture strength, restricting their use primarily to inlays, onlays, and single crowns for anterior teeth [4]. In contrast, materials reinforced with lithium disilicate crystals boast strengths exceeding 400 MPa, making them suitable for single crown restorations in both anterior and posterior teeth. For anterior restorations prioritizing esthetics, a dual-layered all-ceramic crown with feldspathic porcelain over the core is commonly employed [5]. In addition, as for the latest dental ceramic trends, zirconia is a very strong ceramic with a strength of over 1000 MPa, and the latest transparent zirconia is used for both anterior and posterior crowns to improve both esthetics and durability [6]. Hybrid ceramics are a mixture of polymer and ceramic used to increase flexibility and shock absorption, making them advantageous for immediate application, and resin nano ceramics enhance strength and durability through ceramic nano particles to show wear characteristics similar to natural teeth [7]. In addition, multilayer ceramics are popular as products that enhance esthetic perfection with various layers [8]. Although the dual-layered all-ceramic crown is esthetically pleasing, it has been associated with issues such as chipping of the veneered porcelain and cracking or fractures within the core and at the bonding interface [9; 10]. Glass-ceramic restorations have shown fracture patterns in both the veneered porcelain and the core [11]. These challenges can potentially be mitigated by increasing the thickness of the ceramic in areas prone to high tensile stress, optimizing the structural support between the veneered porcelain and the core, and minimizing porosity within the sintered body and micro-gaps at the bonding interface [12]. Microcracks on the surface or bonding interface are primary contributors to veneered porcelain chipping.