NZ603692B2 - Intraoral radiographic imaging sensors with minimized mesial imaging dead space - Google Patents

Abstract

Disclosed is an intraoral radiological imaging sensor. The sensor comprises an electronics substrate and an imaging chip held within a housing. The imaging chip has electronics that create a dead space (9). The sensor also comprises a cable (6) attached to the housing at a cable button connector (11). The sensor has a generally rectangular shape with a mesial side towards which the cable (6) exits the cable button connector (11) and a distal side opposite which the cable (6) exits the cable button connector (11). The electronics are disposed within the housing such that the majority of the dead space (9) is created in the distal side of the sensor. (11). The sensor has a generally rectangular shape with a mesial side towards which the cable (6) exits the cable button connector (11) and a distal side opposite which the cable (6) exits the cable button connector (11). The electronics are disposed within the housing such that the majority of the dead space (9) is created in the distal side of the sensor.

Description

PATENTS FORM NO. 5 Our ref: CHW 234687NZPR NEW ZEALAND PATENTS ACT 1953 COMPLETE SPECIFICATION lntraoral raphic imaging sensors with minimized mesial imaging dead space We, Cyber Medical Imaging, Inc. a company organised under the laws of the State of California of 11300 West Olympic Boulevard Suite 710, Los s, 90064, California, United States of America hereby declare the invention, for which we pray that a patent may be d to us and the method by which it is to be performed, to be particularly described in and by the following statement: (Followed by page 18) ral Radiographic Imaging Sensors with Minimized Mesial Imaging Dead Space Cross—Reference to Related ations This application is a non-provisional utility application that claims the filing date priority of US. Serial No. 61/561,476, filed 11/18/2011, the disclosure of which is specifically incorporated herein by reference.

Field of the Invention The present ion is in the field of intraoral radiographic imaging sensors and their methods of use and, more particularly, to increasing patient comfort during such use.

Background of the Invention Radiographs are fundamental to most dental diagnostic ures.

However, a common complaint and problem during radiographic exams is patient discomfort during the placement of radiographic sensors within the mouth. The majority of these complaints involve the ent of the radiographic sensor in the posterior region of the maxillary and mandibular arches of the patient. This problem is primarily due to the limited space available for proper placement of the sensors within these regions. This has been a problem since the inception of dental radiography using standard x—ray film technology.

Recently, solid-state x-ray sensors have been developed that replace film.

The patient discomfort m for these s is even greater because these devices are rigid by nature and cannot be bent like film to conform to the patient’s anatomy.

As noted in US. Patent No. 7,916,200, a radiological imaging sensor ly comprises a nductor imaging chip having a matrix of photosensitive members and linked electronic components, an electronics ate on which the chip and possibly some other components are mounted, a scintallator covering the chip, and occasionally a fiber-optic plate inserted between the scintillator and the chip. The unit is contained in a resin package from which a connection cable may extend to a system for processing the collected images (except in the case of wireless ission, in which case a y is provided, as a rule, in the package). The package conforms as closely as possible to the shape of the chip so as not to create unnecessary bulk. The shape of the chip which is, a , rectangular requires the package to have a rectangular shape, which is neither ergonomic nor comfortable for the patient.

Some of the most painful radiographs captured are at the mesial aspect of the premolar bitewing and ior premolar periapical views. The reason these radiographs are painful to take is'that' the imaging plate, r a film or a sensor (which is r and can cause more pain), must be d such that its mesial end is placed as far fon/vard in the patient's mouth as possible to capture the distal aspect of the canine teeth and the mesial aspect of the premolar teeth in a bitewing or periapical view radiograph; and once the patient bites down the edges of the film or sensor dig into the tissue on the anterior ing aspect of the maxillary palate or the lingual aspect of the anterior mandibular region; thus often causing pain when the mesial aspect of the digital sensor is impinging against these very sensitive anatomic regions during a radiographic exam.

When a radiograph is being taken with a sensor with a cord, the sensor must be inserted so that the distal end is located towards the distal aspect of the teeth being imaged and then the mesial end is located at the most mesial aspect of the teeth being imaged. This means that the mesial end of the sensor, which is the end at which the cord from the sensor exits the mouth, is toward the front of the mouth at which the cord exits the mouth. By minimizing dead space at the mesial end MS of a sensor, the procedure for obtaining a radiograph of the patient’s ior teeth is far more comfortable and less painful, and better results are obtained.

SUMMARY OF THE INVENTION The present invention is generally directed to an intraoral radiological imaging sensor having an imaging chip held within a housing. The imaging chip does not have a dead space due to imaging chip control electronics at its mesial side because imaging chip control electronics are either located at its distal side or the imaging chip is substantially free of any imaging chip control electronics d outside of an active pixel array, in which case the imaging chip l electronics are located in a control layer deposited underneath the active pixel array or are contained within imaging chip control electronics for individual pixels in the active pixel array. Such an intraoral radiological imaging sensor is especially useful for capturing a premolar bitewing or posterior periapical view radiograph.

The intraoral radiological imaging sensor has an electronics substrate and can have a flat cable attached to its housing more distant to its mesial side than to its distal side at a cable button connector so that the cable exits the cable button connector toward the mesial side of the generally rectangular shaped sensor.

Accordingly, it is a primary object of the present invention to provide an improved intraoral radiographic sensor that can be used to obtain better radiograph images of some teeth. Alternatively it is an object of the ion, to at least provide the public with a useful .

This and further objects and advantages will be apparent to those d in the art in connection with the drawings and the detailed description of the invention set forth below.

Unless the context clearly requires otherwise, hout the description and claims the terms ise”, “comprising” and the like are to be construed in an inclusive sense, as opposed to an exclusive or exhaustive sense. That is, in the sense of “including, but not limited to”.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a partial assembly view that illustrates a prior art ogical g sensor and its primary components. Figure 1A is a photograph of a prior art radiological imaging sensor showing the orientation between distal and mesial and Figure 1B rates a radiograph of the sensor shown in Figure 1A that illustrates the dead space on the mesial end of a typical traditional .

Figure 2 is a side view of a sensor showing a cable button connector located more proximate its distal side than its mesial side.

Figure 3 is a top view cutaway of the sensor of Figure 2 showing certain aspects of a sensor in accordance with a preferred embodiment of the present invention, flat cord exiting the sensor button at a more distal position, with the sensor dead Space located at the distal end of the .

Figure 4 illustrates typical loss of imaging area due to dead space for sensor electronics for a typical l sensor.

Figure 5 illustrates one embodiment of a flat cable useful in a digital sensor according to the present invention.

Figure 6 tually illustrates an imaging chip while Figure 6A conceptually illustrates a n of the active pixel area of Figure 6.

DETAILED DESCRIPTION OF THE INVENTION The following glossary is used for the Figures and description which follows herein: Glossary: 1 radiological imaging sensor 2 electronics substrate 3 imaging chip 4 fiber optic plate CSI scintillator 6 cable 8 dead space attributable to shock absorption al and housing 9 dead space attributable to imaging chip control electronics cable side housing 11 cable button connector front side housing 21 electronic components 32 imaging chip active area 33 pixel 34 pixel control electronics for individual pixel active pixel area 38 imaging chip dead space due to chip construction and not due to imaging chip control electronics 39 imaging chip dead space due to imaging chip control electronics outside of the active pixel area 40 flat cable 41 round cable 42 connector Area A coverage area A for a standard premolar bitewing (film radiograph) Area B coverage area B shows loss of imaging area due to dead space for imaging chip l electronics for a prior art digital sensor CS cable side DS distal side FS front side MS mesial side Figure 1 illustrates a prior art radiological g sensor 1 that has a cable side housing 10 connected to a front side housing with a cable 6 running out of cable button connector 11 in front side housing 15 toward mesial side MS of sensor 1. inside the housing, moving from cable side CS down to front side F8, are an electronics substrate, shown lly as 2, electronic components 21 being mounted on the cable side of electronics substrate 2 (e.g., a c or plastic material), an imaging chip, shown lly as 3 (preferably a CMOS imaging chip), a fiber optic plate, shown generally as 4 (which functions as an x—ray filter for improved noise ion), and a Csl scintillator, shown generally as 5 (optimized for resolution and low noise).

Sensor 1 has a generally rectangular shape, as illustrated in Figure 1. For purposes of the present invention, the shorter sides of the rectangle will always be defined by the direction in which cable 6 exits cable button connector 11. Mesial side MS (see Figure 1) will always be defined as the side toward which cable 6 exits cable button connector 11 while distal side D8 will always be defined as the side opposite which cable 6 exits cable button connector 11, even if cable button connector 11 is not centered in cable side housing 10 (see Figure 2).

In accordance with the present invention, it is especially preferred that cable button connector 11 be located more proximate to the distal side DS than ed (see Figure 2). The reason such placement is preferred is that it allows more room for cable 6 coming out of cable button connector 11 to twist or turn when the sensor is used in some locations of a patient’s mouth, thus reducing stress on the connection n cable 6 and cable button connector 11, which must be watertight.

In typical prior art sensors, electronics substrate 2 has a shock tion material (not shown) around the periphery of ceramic material 22. The space occupied by shock absorption material, as well as space occupied the sensor housing (once cable and front side housings 10 and 15 are assembled together), creates a dead space 8 (see Figure 3) in which a radiographic image is not obtained, and the size of this dead space will typically be no less than 2 mm. in addition to dead space 8, a second dead space 9 is created by imaging chip l electronics located on mesial side MS of imaging chip 3 in presently available sensors, which can represent another 4 mm or more of onal dead space.

The combined effect of dead spaces 8 and 9 in currently available intraoral radiographic sensors is an inability to duplicate the same coverage area in a patient’s oral anatomy as x-ray film when placed in the exact same position relative to the patient’s teeth. This m is due to the intrinsic design and layout of all digital ral s, with regard to the placement of the dead space, which is created as a by—product by parts of the electronics on the sensor. Significantly, this 4-8mm dead space is approximately the width of half to a whole canine, or premolar tooth, as shown in Figure 4.

Figure 4 illustrates a coverage Area A for a rd premolar ng film radiograph. Within Area A, at its mesial side, is another Area B. Area B illustrates a typical loss of imaging area due to dead space for sensor electronics for a digital .

Accordingly, Figure 4 illustrates that if a digital dental sensor is placed in the exact position as the x-ray film, the resultant image will not show the first 4-8mm of the mesial end of the patient’s anatomy.

The first prior art solid-state sensors had the cord exiting off the mesial edge. It was along this edge of the associated g chip that the control electronics were placed, in close proximity to the cord for efficiency of wiring to the cord. As the cord attachment moved to the back side of the sensor allowing for easier bending of the cable and patient comfort when the sensor was used in a vertical orientation in the patient's mouth, the placement of electronics and resulting imaging dead-space, remained the same.

This became part of the industry standard in design and was never questioned e design engineers only t about ease of fabrication, ease of connection, and minimizing signal loss in the placement of the electronics. No thought was given to clinical ergonomic issues.

However, the present invention addresses clinical ergonomic issues, which represents a major change in ral sensor design, by moving dead space 9 to distal side D8 of imaging chip 3 so that any dead space located on the mesial side of the sensor is kept to a bare minimum attributable solely to shock absorption material and the housing. Such a sensor design is shown in Figure 3 which illustrates a cable side view of an electronics substrate 2 according to the present invention with dead space 9 being located at distal side DS, not mesial side MS. For purposes of orientation, cable 6 and cable button connector 11 are shown as trace lines in Figure 3.

Locating dead space 9 at distal side DS, contrary to current practices and traditional wisdom, allows a dental practitioner to capture images not currently able because Area B of Figure 4, which ents a loss of imaging area due to dead space, is minimized, thus allowing r capture of teeth located in the mesial area of a radiograph capture, which is especially important when a bitewing or periapical radiograph is being taken of the canine and premolar teeth. in this regard, some of the most painful raphs captured are the premolar bitewing and posterior periapical views. The reason these radiographs are painful to take is that the imaging plate, whether a film or a sensor (which is stiffer and can cause more pain), must be located such that its mesial end is placed as far forward in the patient’s mouth as le to capture the distal aspect of the canine teeth and the mesial aspect of the premolar teeth in a bitewing or periapical view raph; and once the patient bites down the edges of the film or sensor dig into the tissue on the anterior ascending aspect of the maxillary palate or the lingual aspect of the anterior mandibular region; thus often causing pain when the mesial aspect of the digital sensor is impinging against these very sensitive anatomic regions during a radiographic exam. When a radiograph is being taken with a sensor with a cord, the sensor must be inserted to that the distal end is located towards the distal aspect of the teeth being imaged and then the mesial end is d at most mesial aspect of the teeth being imaged. By minimizing dead space at the mesial end MS of a , the procedure for obtaining a radiograph of the patient’s posterior teeth is far more comfortable and less painful, and better results are obtained.

Accordingly, a sensor in accordance with the present invention, in which dead space in its mesial end is minimized, represents a significant advance over the prior art and allows dental practitioners to obtain much better radiographs of all teeth being radiOQraphed.

It should be noted that the present ion is not limited solely to locating dead space 9 at distal side DS and, in alternative embodiments, it is contemplated that, as much as is possible, the imaging chip control electronics for l sensors should be moved so that they lie within the actual imaging area of imaging chip 3, whether done by sacrifice of active imaging area within individual pixels or by depositing the imaging chip control onics as a layer upon which the active g area is then deposited.

Figure 6 illustrates an imaging chip 3 which has an imaging chip active area 32 made up of dual pixels 33. Each individual pixel 33 has its own pixel control electronics 34 and active pixel area 35. Imaging chip 3 also has an imaging chip dead space 38 due to chip construction and not due to imaging chip control electronics. In current imaging chips, there is also a dead space 39 (although it is located at mesial side MS, not distal side DS) due to imaging chip control electronics e of the active pixel area. The imaging chip control electronics can perform many functions, including intra and inter pixel imaging chip control. Thus, in accordance with the alternative embodiments just noted, dead space 39 of Figure 6 can be eliminated, and capture ency can be improved, by moving all imaging chip control electronics to a layer that lies underneath the active layer of the imaging chip relative to front side FS. This can be done by first depositing an imaging chip control electronics layer and then depositing the active imaging area on top of the already deposited onics layer. Alternatively, or in combination with such a deposited imaging chip control layer, capture efficiency can be increased by including imaging chip control electronics in each pixel’s pixel control electronics 34, even if some'active pixel area 35 must be sacrificed.

Another aspect of the present invention focuses on minimizing fort associated with ing radiographs of teeth with radiological imaging sensors that include a tion cable by changing the shape of the connection cable from round or circular to an asymmetric shape that is substantially wider than its height, preferably at least two or more times wider than its height, examples of which might be ovoid or flat. Such an improved cable, for the remainder of this ption, will be ed to as a flat cable.

A flat cable according to the present invention will be easier to fit to a patient’s mouth while certain radiographs are taken because it reduces cord bulk and bite interference. Rather than having to bite down with a circular cord running out between the patient’s teeth, the patient will now have to bite down on a flat cord that creates less of a gap between teeth, thus sing comfort and imaging coverage of the sensor. Also, use of a flat cord may reduce the ess of cable button connector 11, which should also increase patient t and easier placement of the sensor in the patient’s mouth.

Accordingly, a sensor in accordance with the present invention, in which a flat cord is implemented represents a significant advance over the prior art and allows dental practitioners to obtain much better radiographs of all teeth being radiographed and increased patient comfort.

Current connection cables are round and designed to meet applicable standards for USB connections as well as UL and other applicable standards. The desire to meet USB standards stems, at least in part, for ease of use and the ability to quickly and easily connect with computers.

A flat cable le for use in the present invention can meet USB standards, but it need not necessarily do so. The key design criteria is to reduce the thickness of the flat cable that must fit n upper and lower teeth when certain radiographs are being taken. One possible alternative of a flat cable suitable for use in the present invention uses a short flat cable 40, with a length of approximately one meter or less (not shown to scale), that can be connected to a round USB compliant cable 41 by a small connector, an example of which is shown generally in Figure 5 as 42. (Note that connector 42 can be comprised of a female end on one cable and a male end on the other cable).

When a flat cord is combined with reduced dead space in the mesial end of a sensor, the result is a much improved sensor which provides increased t in a patient’s mouth, improved image coverage at the mesial end, reduced stress on the cord attachment to the sensor housing, improved cord durability and reduce cord bulk and interference.

While the invention has been described herein with reference to certain preferred embodiments, those embodiments have been presented by way of example only, and not to limit the scope of the invention. Additional embodiments thereof will be obvious to those skilled in the art having the t of this detailed ption.

Accordingly, it will be apparent to those skilled in the art that still further s and modifications in the actual concepts described herein can y be made without departing from the spirit and scope of the disclosed inventions.

Claims (7)

What is claimed is:
1. Claim 1: An ral radiological imaging sensor, comprising: an electronics substrate and an imaging chip held within a housing, said imaging chip having electronics that create a dead space; a cable attached to the housing at a cable button connector; wherein the sensor has a lly rectangular shape with a mesial side toward which the cable exits the cable button connector and a distal side opposite which the cable exits the cable button connector; wherein a majority of the dead space is created in the distal side of the sensor.
2. Claim 2: The intraoral radiological imaging sensor of claim 1, wherein the mesial side of the sensor does not have a second dead space created by electronics of the g chip.
3. Claim 3: The intraoral radiological imaging sensor of claim 1, wherein substantially all of the dead space is created in the distal side of the sensor.
4. Claim 4: The intraoral radiological imaging sensor of claim 1, wherein the sensor has a mesial side dead space of approximately 2 mm or less.
5. Claim 5: The intraoral ogical imaging sensor of claim 1, wherein the cable is a flat cable.
6. Claim 6: The intraoral radiological imaging sensor of claim 5, wherein the cable button connector is mounted to a cable side of the housing more distant to the mesial side than to the distal side.
7. Claim 7: An intraoral radiological imaging sensor substantially as herein bed with reference to any one of the accompanying embodiments illustrated in