Year : 2021 Month : June Volume : 10 Issue : 23 Page : 1815-1818

Mobile Phone Assisted 3D Extra Oral Scanner for Acquiring Dental Digital Models - An Innovative Approach

Kapoor Abhijeet1, Eesha Mody2, J. Brintha Jei3, Peter John4, Murugesan Krishnan5, B. Muthukumar6

1, 2, 3, 4, 5, 6 Department of Prosthodontics, SRM Dental College, Chennai, Tamil Nadu, India.

CORRESPONDING AUTHOR

Dr. Kapoor Abhijeet, Department of Prosthodontics, SRM Dental College, Chennai, Tamil Nadu, India.
Email : Kapoorabhijeet9@gmail.com

ABSTRACT

An accurate impression of the edentulous arch is of utmost importance in the rehabilitation of completely edentulous cases. The steps that follow the impression making are highly influenced by the accuracy of the impression.

In order to overcome the manual inadequacies and to improve the accuracy, various advancements have been made manually as well as digitally. Computer-aided design/computer-aided manufacturing (CAD / CAM) is one such digital advancement, which primarily aims at scanning the edentulous arches, followed by subsequent designing of the dentures and processing through various methods such as milling or 3d printing. A major drawback of using CAD / CAM technology is its high cost.

Photogrammetry, as a proof of concept, works on the principle of obtaining reliable information about physical objects through the process of recording, measuring and interpreting photographic images. Recently photogrammetry has been gaining interest in the field of dentistry. It can be used as a more cost-effective alternative for diagnosis, treatment planning and fabrication of surgical guides and in maxillofacial prosthetics.

In the current article, a novel 360-degree mobile phone scanner was devised which rotates around the object and takes images in order to compute a 3d image, which can be further used for treatment planning and fabrication of dentures.

BACKGROUND

The third industrial revolution, with the aid of computers and the internet, revolutionised the development process.1 As a consequence, we have now entered the fourth industrial revolution that focuses on cracking the barrier that discriminates between physical and digital worlds, enabling cyber-physical structures to be developed.2 In all disciplines, the uses of these methods can be seen and have now steadily crept their way into dentistry. The use of this technology in dentistry is primarily intended for the diagnosis, preparation and implementation of various treatments.3 The dentist will bring greater predictability and less chair time to their procedures with the introduction of these methods into clinical practice. Converting a real-time object into a digital model is a common feature of these technologies; there are some substitutes for this method. While the use of computed tomography for bone reconstruction is suggested, there are more effective ways to reproduce dental and oral structures while exposing the recipient to radiation, like 3D scanning.4

With the use of dental scanners, it is possible to obtain digital records with high precision and accuracy, being similar or superior to traditional impressions in some cases.4 The high cost of the devices, however, can still be an obstacle factor for dentists, limiting the digital implementation in their clinics. For this reason, developing low-cost techniques such as photogrammetry is interesting. It is a mathematical method of defining the spatial structure of an object based on the generation of three-dimensional coordinates by locating repeated points in multiple images obtained from different angles of the same object.5

In scientific studies, such as assessing the growth of biological samples in crop media, developing plant structures and obtaining medical parameters from patients, this technique has been used with great reliability.6-8 Photogrammetry has also been used in the field of dentistry to acquire digital models by taking intraoral and extra-oral images, and is also a very useful method for preparing and assessing the outcomes of maxillofacial surgery by providing a good soft tissue register.9 The digital camera was used to capture and record the images in this process. This article describes the use of a mobile phone camera to obtain 2D object images, and these images have been turned into a 3D digital model using free software, making it even more cost-effective.

METHODS

  1. Design the prototype using (Autodesk fusion 360, California, USA). It consisted of two circular platforms which was 10 inches in diameter, a rotating device and a mobile phone holder.
  2. The two-part circular platform was prepared and the pieces were printed in four segments for ease of printing and were later connected with the aid of connectors. Each of the circular platform segments measured around 1 1 / 2 inches in width.
  3. The sections of the designed circular platform were printed using a polylactic acid material (Rever Industries, India) Fusion Deposition Modelling 3D printer (Creality Ender3, China) (Figure 1).
 
 

 

4. The rotary unit (Tower Pro Micro Servo 9 g, Italy) was attached to the circular platform and connected to it by a mobile phone holder (Bosynoy Vogue, India).

5. The Arduino board (Arduino uno SMD R3, Italy) was used to calibrate this rotating mechanism to stop the platform after 80 rotation (Figure 2).

 

 

6. Maxillary edentulous cast was made using a preliminary impression of an edentulous mould with irreversible hydrocolloid impression material (Zelgan plus; Dentsply Sirona).

7. Using a straight fissure carbide bur (Dentmark, India), four holes on the ridge of the cast were drilled. In the canine region, called C1 and C2, two holes were made and the other two holes were made in the molar region, M1 and M2 respectively (Figure 3).