News

Knowledge

Company News

Application Mind Map

Test Report

Technical Article

Industry News

Addressing Typical Challenges in Dental UV 3D Printing (Part 5)

Release time:

2026-08-18 23:06

Addressing Typical Challenges in Dental UV 3D Printing (Part 5)

Layer lines are an inherent feature of stereolithography‑based 3D printing, arising from the layer‑by‑layer additive manufacturing process. In dental applications, the increased surface roughness caused by layer lines can create favorable conditions for bacterial adhesion, while stress concentrations in these regions may also compromise the long-term durability of printed parts. Addressing both layer line formation and surface roughness requires a dual approach: optimizing printing parameters and employing advanced post‑processing techniques.

I. Parameter Optimization for Layer Thickness and Print Orientation

Layer thickness is the primary factor influencing the visibility of layer lines. The thicker the layer, the more pronounced the stair-stepping effect between layers and the higher the surface roughness. Dental restorations typically feature fine margins and curved surfaces; reducing layer thickness helps minimize the stair-stepping effect and achieve a smoother surface.

The orientation of the printed part also affects the visibility of layer lines. On curved or inclined surfaces, layer lines are more pronounced than on flat surfaces, because in curved regions the boundaries between layers do not align with the surface’s tangent direction, making the stair‑stepping effect more evident. During the slicing stage, carefully planning the model’s build orientation—placing critical curved surfaces facing upward or to the side—can reduce the visibility of layer lines on those key areas. For restorations with complex curvatures, such as dental crowns, it is advisable to evaluate, prior to printing, how different orientations impact surface quality.

II. Applications of Post-Processing Technologies

Post-processing techniques such as centrifugal coating can effectively fill hierarchical structures, significantly reduce surface roughness, and decrease bacterial adhesion. This approach forms a uniform coating on the printed part’s surface, leveling the microscopic valleys between layer lines and resulting in a smoother finish.

Polishing also helps improve surface quality. By mechanically grinding away protruding layer‑ridge peaks, surface roughness can be reduced. However, care must be taken to avoid excessive polishing, which could compromise the print’s geometric accuracy. For restorations with complex geometries, a combined approach of mechanical and chemical polishing may be considered to enhance surface smoothness while preserving the intended shape. The degree of polishing should be tailored to clinical requirements; over‑polishing can expose underlying resin layers that have not fully cured.

III. Adjustment of Post-Curing Time

Post‑curing time affects surface wear resistance. An appropriate post‑curing duration helps increase the print’s hardness, making the surface more wear‑resistant. However, over‑curing can render the material brittle, thereby increasing the risk of microcracking under stress.

The post‑curing time should be adjusted according to the resin type, ensuring effective polymerization while avoiding over‑curing. Different resin types exhibit varying responses to post‑curing; therefore, curing times must be set in accordance with the material’s specifications. For restorations requiring high surface quality, it is recommended to determine the optimal post‑curing conditions using test specimens.

IV. Conclusion

Addressing layer lines and surface roughness requires a two-pronged approach: optimizing printing parameters and applying appropriate post‑processing techniques. Reasonable settings for layer thickness and print orientation can minimize the visibility of layer lines; post‑processing methods such as centrifugal coating and polishing can significantly enhance surface smoothness; and carefully adjusting the post‑curing time helps balance surface hardness and toughness. For orthodontic appliances and restorations intended for long-term wear, it is advisable to incorporate surface‑quality optimization into both the printing parameter settings and the post‑processing workflow, thereby reducing the risk of bacterial adhesion and improving wearer comfort. When used in concert, these strategies can effectively improve the surface quality of dental UV‑based 3D‑printed components.

Disclaimer: The above content has been compiled from publicly available sources and is provided for reference only. If any infringement occurs, please contact us, and we will address it promptly.

Bossin Related Product Recommendations – 3D Printing
Dentistry
Product Model/English Abbreviation	Product Name/Product Type	Product Features
B-100M	Bisphenol A epoxy acrylate	Low viscosity, high hardness, high gloss, and high body.
B-113	Bisphenol A epoxy acrylate	High hardness, high gloss, high fullness, contains 20% TPGDA.
B-276H	Aliphatic polyurethane acrylate	High hardness, fast curing, excellent toughness, and low yellowing.
B-296	Aliphatic polyurethane acrylate	Fast curing, chemical resistance, yellowing resistance, impact resistance
B-296M	Polyurethane acrylate	Fast curing, resistant to polar solvents, yellowing-resistant, and impact-resistant.
B-301	Aromatic polyurethane acrylate	Fast curing, excellent toughness, and good sandability.
B-302	Aromatic polyurethane acrylate	Fast curing, high strength, excellent toughness, and good grindability.
B-368	Aliphatic polyurethane acrylate	Good toughness, excellent leveling, excellent bend resistance, and excellent heat resistance.
B-376	Aliphatic polyurethane acrylate	LED yellowing is minimal, and the nail polish formulation exhibits excellent stability.
B-609	Aliphatic polyurethane acrylate	Fast curing, high hardness, scratch resistance, and chemical resistance.
B-79D	Polyester acrylate	High hardness, low yellowing, and high evaporation efficiency at elevated temperatures.
Monomer Recommendation
Product Model/English Abbreviation	Product Name/Product Type	Product Features
BM1211 (HPMA)	Hydroxypropyl methacrylate	HEMA-free, high strength, low irritation, and high adhesion
BM2223 (TPGDA)	Di(propylene glycol) diacrylate	Good flexibility and low volatility
BM3231 (TMPTA)	Trimethylolpropane triacrylate	High crosslink density, high hardness, high gloss, and excellent wear resistance.
BM3235 (PET3A)	Pentaerythritol triacrylate	Fast curing, high crosslink density, high hardness, and chemical resistance.
BM3380 (3EO-TMPTA)	Pentaerythritol triacrylate	More flexible and less irritating than TMPTA.

Share to:

Addressing Typical Challenges in Dental UV 3D Printing (Part 6)

Addressing Typical Challenges in Dental UV 3D Printing (Part 4)