Electronic Impression Technique(EIT)
It is somewhat like an impression tray. The impression tray has walls all around it except on the posterior (Vibratory Line), but the tray for EIT has walls all around including the posterior (Vibratory Line). This new tray is made of a plastic and is bit bigger than the individual (according to sizes) regular tray. This tray has sensor all over it like the pixels in the televisions. These sensors produce lasers in a vertical and horizontal manner. Horizontal lasers are produced by all the walls including the posterior wall (Vibratory Line) and the vertical lasers are produced by the floor of the tray. These lasers will read all the areas, convexities and concavities of the oral cavity. The labial and buccal areas of tooth and gingival area will be read by the walls of the tray through horizontal lasers, the lingual/palatal areas of tooth and gingival will be read by the posterior (Vibratory Line) wall through horizontal lasers. The hard palate, vestibule and portion of al tooth areas will be read by the floor of the tray through vertical lasers.
NOTE* The mandiblar EIT trays is same as the regular trays with extra walls covering retromolar pad area.
**The lasers read and record all the required data of the oral cavity in a similar fashion that is done by satellites to read the geographical areas of earth.
Note: CCD cameras can also be used instead of Lasers.
The data read by horizontal and vertical lasers/CCD-CAM would be recorded in the computer as a whole. This will give us a three dimensional figure of the oral cavity on the Computer screen. Now this figure can be modified through computer in no time. For example, a data for FPD temporary restoration as a mock preparation (Tooth # 11, 1mm buccal, 0.5mm palatal) is commanded to the computer. The computer flashes a new figure with a prepared tooth # 11 for FPD temporary crown.
Now the data of both the figures (one at a time) are sent to this machine according to machine’s language. This machine is somewhat like a box. It has a stage in the middle where already prepared block of Plaster or Dental stone is placed. All four walls and the ceiling of the box consist of Pin Fields. The fields have pins with a very minimal diameter, and the pins are compactly arranged with one another. The pins are arranged in somewhat similar fashion to the sensor of the Tray or to that of the television pixels.
The machine will convert the three dimensional figure in its own language. After which the tiny little pins from the fields starts to elevate in a speed and start to abrade the block of plaster/stone. For example, the laser on the tray recorded a data of 10mm on cervical and increment of 0.05mm towards the convexity with 11mm on the highest convex area. In the machine the group of pins will rise/elevate up to 10mm and abrade the block to create a cervical area. Another group of pins just adjacent to the first one will rise up to 10.05mm to continue abrading the block and increases so forth to abrade the block up to the highest convex area of 11mm.
The horizontal lasers produced by the walls of the EIT tray will be represented by the horizontal pins in the four walls of the box (machine) and the vertical lasers produced by the floor of the EIT tray would be represented by the vertical pins in the ceiling of the box (machine). The floor of the machine would serve as the base/stage. A single laser/CCD-CAM will measure a very small portion of the oral cavity and this data will be converted in the machine and a single pin representing the same laser will abrade the portion on the block of plaster/stone. When all the lasers of the EIT tray and representing pins of the machine would work as a whole, we will have a sculpture of the oral cavity with no voids, inside the machine.
The pins are very minimal in diameter which requires a very minimal force to abrade the block and prevents fracture. When tiny little pins would group together and abrade the block then it will be possible to create a bigger concavities or convexities.
Instead of the machine mentioned above, we can also make use of a similar machine currently present that makes sculptures with lasers or with water jets.
The three dimensional figure in the computer can also be utilized as a diagnostic record of the patient since it will show all the defects including the cavities or caries.
Advantages: (if it will work)
No need of manipulating the impression materials especially hot modeling compound.
No need to worry about setting time of the impression materials.
Very less time consuming, since EIT is basically placing a tray inside the oral cavity and taking a picture.
No hassles of mixing plaster/stone and pouring it in an impression in a limited time avoiding air bubbles.
The EIT tray, the computer and the machine will do the entire job in no time.
All the defects and cavities will be recorded in the computer. No need to check the teeth one by one.
Disadvantages: (if it will work)
The machine can make mistakes that can be avoided by the naked eyes of the dentist.
Intra-Oral Digital X-ray
This idea is also about a tray that can be used to take x-rays. It is quite similar to EIT trays.
These X-ray trays do not have posterior wall (Vibratory Line) or walls covering the retromolar pad, just like the regular impression trays. The remaining walls are little thicker to provide space or distance for the exposure. The external portion of the walls is connected to the small cords. These cords are attached to tiny little boxes which produces x-ray beams. These boxes are attached to the trays and are very close to the subject (the tooth).
Electrical currents are made to travel through the cords directing towards the boxes where the x-ray beams are produced. These boxes are in close approximation to the tooth. As soon as the beams are produced, it is directed towards the tooth. This will allow less scattering of the beams. One cord will represent one box for one tooth or two tooth areas.
The palatal portion of the X-ray tray would be provided with flexible rubber material that holds the x-ray film firmly against the palate. For this tray there can be made a special film which is long and adapted to these x-ray trays or we can simply make use of current periapical films.
Each cord will be connected to a controller and each cord will be named according to the tooth or the tooth area. For example, the cord that will expose right upper central incisor area will be named as CORD # 11.
We can make use of new long x-ray film adapted to the x-ray tray to expose all the teeth simultaneously or we can expose only few teeth through the controller. On the controller, the cords representing the teeth to be exposed will be activated while all the rest of the cords will be deactivated.
The x-ray trays are large enough to rotate within the oral cavity to be able to expose the tooth for Buccal Object Rule (BOR).
Or we can make use of this technique as digital where the computer interprets the data.
A lead mask is provided that covers the mouth and neck all around. This helps the rays to be limited within the oral cavity.
Advantages: (if it will work)
No angulations problem.
The size of the image will be close to the size of the exact tooth because the rays are in close proximity to the tooth.
X-ray hazards which diverge from the current PID can be limited.
Very easy to operate.
Disadvantages: (if it will work)
Intra-Oral Rubber Dam Unit
The unit has the following parts:
Frame (can be reused with proper infection control technique; it is provided according to sizes like small, medium or large)
The body is made of a strong rubber that can be easily displaced and at the same time can stay firm (strong elastic in nature). It has two portions or areas, the buccal portion and the palatal/lingual portion. These areas are placed firmly all around the buccal and the palatal/lingual attached gingiva just below the free gingival area. The rubber of the body is strong and elastic enough to provide a firm and proper seal all around buccal and the palatal/lingual attached gingiva.
There is a space (teeth space) (Fig.3) provided in between the buccal and the palatal/lingual portion. This space allows all teeth to be displaced together with the dam proper (Fig.2). As the teeth are displaced through the space together with the dam proper the buccal and the palatal/lingual portion is firmly placed all around the attached gingiva providing a proper seal.
Bite Block Pillars (Fig.3)
It supports the body and allows the patient to bite on it and to open the mouth constantly during the treatment.
Bite Block Pillars are slightly medial (broader) than the body to provide room for the patient to bite. And the bite block pillars are placed below the level of the body so that when the patient bites on it the body is moved towards the attached gingival level displacing the teeth through the teeth space.
Types of Frame:
Anterior Working Frame
The Bite Block Pillars of both sides are extended up to first or second molar area (the size and shape of the Bite Block Pillar is similar to the bite block currently in use). It is used while working only on anterior teeth of both sides.
Unilateral Working Frame (Left or Right)
The Bite Block Pillar of only one side (either left or right) is extended anteriorly up to the first premolar or canine area (the shape of the Bite Block Pillar is wider). There is no bite block pillar provided on the opposite side. It is used while working on posterior teeth (or all teeth) of only one side (left or right).
Rubber Dam (disposable)
Face Strap (Fig.1 and Fig.2)
It is attached with the dam proper (Fig.2). This portion of the rubber dam is placed outside the mouth and around the head. It can be either tied or can be provided with the self adhering strap (the adhering strap which can be seen in bags and shoes) or can be stabilized with current frame in the market. Since it is made of a rubber material it serves similar to that of head rubber band that females use to manage their hair.
The superior border of the face strap is place on the philtrum area just below the nose. The face strap depresses the lip firmly and do not block the air way of the nose. The inferior border is placed on the chin area.
The opening (Fig.1 and Fig.2)
Provides access inside the oral cavity.
Dam Proper (Fig.2)
It is made according to the anatomy of the mouth. It is somewhat like a balloon, made of the same material as the rubber dam currently in use.
It is placed inside the oral cavity and it can be provided with dark dots Guiding Dots (Fig.2) representing the individual tooth as a guide for punching holes for the treatment.
A hole is punched on the dam proper according to the guiding dots provided, depending on the tooth to be treated.
The dam proper is then placed inside the mouth and the tooth is passed through the punched hole.
The frame is then placed inside the dam proper (inside the mouth) and the patient is asked to bite on the bite block pillars. This enhances the body to move towards the attached gingiva while all the teeth are passed through the teeth space. The tooth to be treated will be exposed through the teeth space due to the punched hole while all the remaining teeth are displaced through the teeth space together with the dam proper as a cover. And there is a proper seal due to the elasticity of the body.
After the frame and dam proper are in place, the face strap is tightly brought at the back of the head and it is either tied or is adhered with self adhering straps. Or instead of face strap, the regular frame in market can be used, if the Dam Proper is provided with extra rubber material to support the frame.
The Intra-Oral Dam Unit will eliminate the use of metal clamp by replacing it with a non-painful rubber frame. The unit is placed inside the patient mouth with a firm and proper seal isolating the involved tooth. During the treatment the bite block pillars enhances the patient to open the mouth constantly without any jaw pain because the patient would actually bite rather than just opening the mouth for a long time.
While using this unit, all the debris and cleansing agents are collected on the dam proper (due to its shape, like a balloon) and can be easily ejected with the saliva ejector. And also that it prevents the aspiration of foreign bodies and debris.
X-rays can be taken while the unit is still in its place.
Note: We can make use of current dam frame instead of face strap, when provide with extra rubber material around the dam proper instead of face strap.
Please check other pages for figures. Sorry for the poor drawings.
4. Hand-Piece with camera
If the Dental Hand-Piece is provided with a camera and light then visualization problems especially on the posterior region can be solved.
A company named OmniVision has come with the smallest camera in the world. Model No. OV6920, this camera is only about 2.1mm X 2.3mm.
This camera can also be utilized in Dental Hand-Piece.
The camera would be installed at the superior region of head of Hand-Piece. The cord would follow the side ways of the head (since it cannot be placed within the head because most of the space would be occupied by the cartridge). As soon as the cord reaches the shaft, it enters inside the body and exits at the rare end. Following the same pattern or path, we can also install a regular flash light or a fiber optic light. The camera’s lens would be covered by water resisting convex transparent glass or plastic.
Since the continuous water jets might prevent clear view of the camera, we can place an air burst directing to the lens. This air would be supplied from the main Air Supply of the Hand-Piece. Small channel could be extended, that runs along the curvature of the head of the Hand-Piece and exits right on the concave glass of the camera.
From the regular Hand-Piece, this new one would have two extra small channels on the lateral sides (either same side or both) of head region. One superiorly, that holds the cord of the camera, and one inferiorly that supplies air to the camera’s lens.
This camera would provide continuous image on the chair side monitor with enlarged view of the tooth and the preparation.
Difficulties of mouth mirrors can be eliminated.
Better view for restoration and more convenient for RCT preparations.
Distal Areas of posterior tooth can be visualized properly during tooth preparation.
Preparations could be magnified for better visualization.
Sorry for the poor drawings.
Figure 1: Dotted area shows the path of camera cord; dark area is regular water supply; larger stripe area is the regular air supply; smaller stripe area is new extension supplying air to the camera’s lens.
Figure 2: Dark area is the extension of air supply directing to the lens; stripe area would be the camera and its cord. Both will follow the curvature of the Hand-Piece externally. Both channels enter inside the body, just before the shaft starts. This would not differ or interrupt with the handling of the Hand-Piece.