Lithium Silicate Glass Ceramic for Fast Machining and Heat-Hardened Strength
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lithium disilicate glass ceramics are difficult to machine due to their high strength, leading to high tool wear and slow processing, which is problematic for single-session dental restorations.
Innovation Solution
A lithium silicate glass ceramic with lithium metasilicate as the main crystal phase, comprising no more than 30 wt.-% of lithium metasilicate crystals, allowing for easy machining and subsequent conversion into high-strength dental products with excellent optical and chemical properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If conventional lithium disilicate glass ceramic is used, then high mechanical strength is achieved, but machining difficulty increases and tool wear increases
Solution Approach 1:
The patent changes the crystal phase composition parameter by limiting lithium metasilicate to no more than 30 wt.-% and requiring lithium disilicate to be the main crystal phase. This parameter change creates a material with optimized balance between machinability and final strength, allowing the precursor to be easily machined while the final heat treatment achieves high mechanical strength.
2Strength
If conventional lithium disilicate glass ceramic is used, then high mechanical strength is achieved, but machining speed decreases
Solution Approach 1:
The patent applies preliminary action by first creating a precursor material with specific crystal phase composition that is optimized for easy machining, then performing the final strength-enhancing heat treatment after machining is complete. This allows high-speed machining of the precursor followed by conversion to the high-strength final product.
3Productivity
If lithium metasilicate glass ceramic is used, then machining speed increases, but final mechanical strength decreases
Solution Approach 1:
The patent utilizes phase transitions by controlling the crystal phase composition in the precursor (with lithium metasilicate limited to ≤30 wt.-%) to enable easy machining, then applying heat treatment to transform the material into the final high-strength state with lithium disilicate as the main crystal phase. This phase transition approach allows optimization of machining speed in the precursor stage and mechanical strength in the final stage.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The lithium silicate glass ceramic can be machined faster than conventional lithium metasilicate glass ceramics, achieving high mechanical strength and chemical resistance after heat treatment, suitable for single-session dental restorations.
Implementation Method 1
This precursor is then subjected to further heat treatment to form the desired high-strength lithium disilicate glass ceramic
Implementation Method 2
a glass ceramic with lithium metasilicate as the main crystal phase is first produced as a precursor
Data Source
AI summary
A lithium silicate glass ceramic having lithium metasilicate as main crystal phase and having not more than 30 wt.-% of lithium metasilicate crystals.