Endodontic Radiopacifying Application of Barium Titanate Prepared through a Combination of Mechanical Milling and Heat Treatment

Hsiu-Na Lin; Wei-Wen Chen; Chun-Chun Hsu; May-Show Chen; Pei-Jung Chang; Wei-Min Chang; Fang-Hao Zhang; Chin-Yi Chen; Pee-Yew Lee; Chung-Kwei Lin

doi:10.3390/ma16237270

Endodontic Radiopacifying Application of Barium Titanate Prepared through a Combination of Mechanical Milling and Heat Treatment

Materials (Basel). 2023 Nov 22;16(23):7270. doi: 10.3390/ma16237270.

Authors

Hsiu-Na Lin^{1

2

3}, Wei-Wen Chen⁴, Chun-Chun Hsu^{5

6

7}, May-Show Chen^{1

3

8}, Pei-Jung Chang^{1

9}, Wei-Min Chang^{1

10}, Fang-Hao Zhang¹¹, Chin-Yi Chen^{1

12}, Pee-Yew Lee^{1

11}, Chung-Kwei Lin^{1

13}

Affiliations

¹ Research Center of Digital Oral Science and Technology, College of Oral Medicine, Taipei Medical IUniversity, Taipei 110, Taiwan.
² Department of Dentistry, Chang Gung Memorial Hospital, Taipei 105, Taiwan.
³ School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei 110, Taiwan.
⁴ Center of Dental Technology, Chang Gung Memorial Hospital, Linkou, Taoyuan 333, Taiwan.
⁵ School of Respiratory Therapy, College of Medicine, Taipei Medical University, Taipei 110, Taiwan.
⁶ Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei 110, Taiwan.
⁷ Division of Pulmonary Medicine, Department of Internal Medicine, Taipei Medical University Hospital, Taipei 110, Taiwan.
⁸ Division of Prosthodontics, Department of Dentistry, Taipei Medical University Hospital, Taipei 110, Taiwan.
⁹ Graduate Institute of Manufacturing Technology, National Taipei University of Technology, Taipei 106, Taiwan.
¹⁰ School of Oral Hygiene, College of Oral Medicine, Taipei Medical University, Taipei 110, Taiwan.
¹¹ Department of Optoelectronics and Materials Technology, National Taiwan Ocean University, Keelung 202, Taiwan.
¹² Department of Materials Science and Engineering, Feng Chia University, Taichung 407, Taiwan.
¹³ School of Dental Technology, College of Oral Medicine, Taipei Medical University, Taipei 110, Taiwan.

Abstract

Mineral trioxide aggregates (MTA) are commonly used as endodontic filling materials but suffer from a long setting time and tooth discoloration. In the present study, the feasibility of using barium titanate (BTO) for discoloration and a calcium chloride (CaCl₂) solution to shorten the setting time was investigated. BTO powder was prepared using high-energy ball milling for 3 h, followed by sintering at 700-1300 °C for 2 h. X-ray diffraction was used to examine the crystallinity and crystalline size of the as-milled and heat-treated powders. MTA-like cements were then prepared using 20-40 wt.% BTO as a radiopacifier and solidified using a 0-30% CaCl₂ solution. The corresponding radiopacity, diametral tensile strength (DTS), initial and final setting times, and discoloration performance were examined. The experimental results showed that for the BTO powder prepared using a combination of mechanical milling and heat treatment, the crystallinity and crystalline size increased with the increasing sintering temperature. The BTO sintered at 1300 °C (i.e., BTO-13) exhibited the best radiopacity and DTS. The MTA-like cement supplemented with 30% BTO-13 and solidified with a 10% CaCl₂ solution exhibited a radiopacity of 3.68 ± 0.24 mmAl and a DTS of 2.54 ± 0.28 MPa, respectively. In the accelerated discoloration examination using UV irradiation, the color difference was less than 1.6 and significantly lower than the clinically perceptible level (3.7). This novel MTA exhibiting a superior color stability, shortened setting time, and excellent biocompatibility has potential for use in endodontic applications.

Keywords: barium titanate; discoloration; mechanical milling; mineral trioxide aggregates; radiopacifier; radiopacity; setting time.

Abstract

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