Patent Description:
Personalised Regenerative Medicine is the phrase that describes the current trend towards using natural, non-animal products to harness and accentuate the body's natural healing process. These biomedical technologies are aimed at stimulating tissue regeneration by applying autologous proteins to a target treatment site.

In oral surgery and implantology one commonly used way of doing this is with the use of Platelet-Rich Plasma (PRP). This technique involves taking a sample of the patient's blood, centrifuging it to separate the base constituents (red blood cells, leukocytes and plasma) into layers and extracting the blood plasma with the associated platelets and proteins.

The platelet rich blood plasma extracted from the patient's blood may be injected to a target treatment site within the patient's mouth to promote bone growth or augmentation. A dental implant may subsequently be fitted to the augmented bone.

However, the current method of maxillary sinus bone augmentation procedures is a much more invasive procedure that involves using animal products to promote bone growth and healing. These animal products can be of bovine, porcine or equine origin. Injecting platelet rich blood plasma to a target treatment site is a less invasive procedure and there is a lower risk of the patient's delicate maxillary sinus lining rupturing or bursting when the blood plasma is injected at the target site. There is also a much reduced chance of the patient having an adverse or allergic reaction to the blood plasma treatment when compared to the use of animal products. The PRP treatment is <NUM>% autologous.

To inject the animal derived bone augmentation materials to a to a target treatment site the dental surgeon initially anaesthetises the patient in the region of the target site. The dental surgeon may then gain access to the maxillary sinus using a lateral window approach. The dentist raises a larger full thickness mucosal flap, <NUM> to <NUM> centimetres long in the patient's gum as the access point to the target treatment site within the maxillary sinus. An access hole is then made through the bone of the anterior wall of the maxillary sinus to allow the surgeon to deliver bone augmentation materials to target site.

This access window can be up to <NUM> x <NUM> in dimension. Care must be taken not to perforate the delicate Schneiderian Membrane which lines the interior surface of the sinus. There is a need for apparatus that allows the access window to be created at the target site without the risk of rupturing or damaging the patient's Schneiderian Membrane. The Schneiderian membrane is then detached from the walls and floor of the sinus using specialised metal instruments and working through the access window. If the membrane ruptures it may be necessary to abandon the procedure and repeat it with a second attempt, after a suitable healing period, usually <NUM>-<NUM> months. The bone augmentation material is then spooned or syringed into the sinus, In the area of required augmentation, between the patient's bone and Schneiderian membrane. At this stage the surgeon must again take care not to perforate the membrane of the sinus.

The lateral window approach is an invasive procedure which involves lifting a surgical flap of the patient's gum and creating an access window through the patient's bone to gain access to the target site for bone augmentation within the patient's sinus cavity. Furthermore, due to fragile nature of the sinus membrane the dentist must take extreme care not to rupture the sinus lining when separating the membrane from the bone and when delivering the bone substitute material to the target site. This is a challenging procedure with a high risk of failure, infection or morbidity for the patient.

There is therefore a need for a less invasive procedure to target the delivery of a biocompatible substrate that will induce the formation of the patient's bone, within the patient's sinus cavity. The substrate is Platelet Rich Plasma, obtained from a sample of blood from the patient that is centrifuged and processed. This separates the blood plasma from the remaining blood constituents. The separated plasma is heated in an oven to prepare the PRP gel in accordance with the standard treatment protocol for the PRP gel. Furthermore, there is a need for apparatus that allows the blood plasma to be delivered to the target site without the risk of rupturing or damaging the patient's sinus membrane.

<CIT> describes an apparatus and method for lifting the maxillary sinus mucous membrane during liquid injection.

In an aspect of the present invention, there is provided a nozzle for a syringe for distributing blood plasma at a target treatment site within a patient's mouth, the nozzle comprising: a body having a passage extending through the body along a longitudinal axis of the body, the passage extending from a proximal end to a distal end of the body; an inlet to the passage at the proximal end for receiving blood plasma from the syringe; an outlet from the passage at the distal end for distributing blood plasma at the target treatment site; wherein the outlet comprises an outlet aperture located on a distal tip of the nozzle; and at least one exit gate extending from the passage through the distal end of the body, wherein the at least one exit gate tapers outwardly from the passage.

The nozzle beneficially allows platelet rich blood plasma to be distributed at a target treatment site without damaging or tearing the maxillary sinus lining of a patient. This may be achieved by promoting distribution of the blood plasma at the target treatment site through a plurality of exit gates and an outlet aperture at the distal tip of the nozzle. The outlet aperture may be relatively narrow, for example about <NUM> in diameter which minimises the flow of blood plasma that may be in direct contact with the sinus lining.

Furthermore, the at least one exit gate may extend substantially perpendicularly from the passage such that blood plasma flowing from the exit gates such that the blood plasma is distributed generally uniformly at the target treatment site thereby preventing pressure spikes associated with a single stream of blood plasma from a conventional needle.

The cross-sectional area of the exit gate may be smaller at the passage compared to the outlet of the exit gate. This is beneficial as the increasing cross-sectional area of the at least one exit gate helps to reduce the velocity of fluids, for example blood plasma, exiting the exit gates. This in turn helps to promote a uniform distribution of blood plasma at the target treatment site and the reduced fluid velocity and pressure reduces the chance of damaging the maxillary sinus lining membrane.

In one embodiment the body may comprise a distal shoulder extending around an external surface of the body. The distal shoulder beneficially may contact the maxillary bone, in use, and form a seal between the nozzle and the bone. The seal beneficially ensures that blood plasma exiting the outlet of the nozzle is distributed within the patient's sinus cavity and does not leak out of the target treatment site and into the patient's mouth. Furthermore, the seal encourages a gradual building of pressure at the target treatment site which may cause the maxillary sinus lining membrane (Schneiderian Membrane) to lift off the maxillary bone such that blood plasma may be distributed within the cavity created by the lifting of the maxillary sinus lining membrane from the maxillary bone.

In an embodiment the distal end of the body may extend distally from the distal shoulder. Furthermore, the distal end of the body may taper in a distal direction from the distal shoulder towards the distal tip along the longitudinal axis. This is beneficial as the distally tapering distal end makes it easier to locate the distal tip within the hole in the maxillary bone. This will also aid in creating the seal, prior to injecting the platelet rich blood plasma, should there be some discrepancies created in the access hole diameter, due to inherent anatomical features or the drilling process. The distal end of the body may be frustoconical such that the distal tip is generally planar.

In another embodiment the body may comprise a proximal shoulder extending around the external surface of the body. The proximal shoulder beneficially provides an abutment surface for a flexible tube that may be pressed over the proximal end of the nozzle to secure the nozzle to a syringe. The proximal end of the body may extend proximally from the proximal shoulder and the proximal end of the body may taper in a proximal direction from the proximal shoulder towards the proximal end along the longitudinal axis. Beneficially, this taper aids in the creation of frictional retention and seal of the flexible tube to the nozzle. As such, the proximal end of the body may be frustoconical such that the proximal tip is generally planar or flat.

In one embodiment the inlet may be positioned on the proximal tip and the inlet may be concentrically aligned with the longitudinal axis of the body. The inlet may be in fluid communication with the passage and the passage may convey fluids from the inlet to the outlet.

In an embodiment a central body portion may be defined between the distal shoulder and the proximal shoulder. The central body portion may taper in a proximal direction along the longitudinal axis from the distal shoulder towards the proximal shoulder. This is beneficial as the central body portion may provide a surface that a dental surgeon may grip. Furthermore, the proximally tapering central body portion allows the dental surgeon to push or urge the nozzle towards the maxillary bone to maintain a seal between the distal shoulder and the maxillary bone. Alternatively, the central body portion may have substantially parallel sides such that the cross-sectional area of the central body portion is substantially constant along the longitudinal axis between the proximal and distal shoulders. The outer surface of the central body portion may further comprise a textured surface so as to provide improved grip to the dental surgeon.

In one embodiment the nozzle may comprise four exit gates positioned circumferentially around the distal end of the body. Each exit gate may extend substantially perpendicularly from the passage to an external surface of the distal end of the nozzle. The at least one exit gate or all four exit gates may be generally square shape. In another embodiment the nozzle may comprise two, three or five exit gates.

As part of the invention there is further provided a syringe for delivering blood plasma to a target treatment site comprising a nozzle. Optionally, the nozzle is attached to, and in fluid communication with, the syringe via a flexible tube.

There is further provided an osteotome, the osteotome comprising: a body having a longitudinal axis; the body having a distal end, and the body comprising a distal shoulder extending around an external surface of the body; the distal end of the body extending distally from the distal shoulder, and wherein the distal end of the body tapers in a distal direction from the distal shoulder towards a distal tip along the longitudinal axis.

The taper and shoulder may beneficially allow a dentist to use the distal end of the osteotome to create an access opening having a maximum depth in a bone of a patient, particularly, but not limited to, the maxillary bone of a patient. The maximum depth of access opening that the osteotome can create is equal to the distance between the distal shoulder of the osteotome towards a distal tip of the osteotome along the longitudinal axis.

Optionally, the distal end of the body of the osteotome is frustoconical such that the distal tip is generally planar. The distal tip of the osteotome being generally planar may provide the advantage that a planar tip is less likely to damage the Schneiderian Membrane, if the osteotome is used in a patient's maxillary bone.

There is also provided a kit for creating a hole in the maxillary bone of a patient, the kit comprising: a first osteotome and a second osteotome, the first osteotome having a first distance between the distal shoulder towards a distal tip along the longitudinal axis; the second osteotome having a second distance between the distal shoulder towards a distal tip along the longitudinal axis; the first and the second distances being non equal.

Optionally, the kit further comprises a third osteotome having a third distance between the distal shoulder towards a distal tip along the longitudinal axis; the third distance being non equal to either the first or the second distances.

When a kit of osteotomes is provided, the kit including osteotomes that have different dimensions, this allows a dentist/surgeon to use the kit of osteotomes to iteratively use osteotomes of increasing size/dimensions to gradually enlarge an access hole in the bone of a patient. By selecting an osteotome that has an appropriate distance between its distal shoulder and its distal tip, a dentist/surgeon has much greater control over the depth of access hole that they drill. If the kit of osteotomes are used in a patient's maxillary bone, this allows a dentist/surgeon to select an osteotome with dimensions that should not protrude too far through the maxillary bone, and are therefore much less likely to damage the Schneiderian Membrane of the patient.

There is also provided a kit for use in surgery, the kit comprising: an osteotome, and a nozzle for a syringe, and wherein: the length of the distal end of the body of the nozzle matches the length of the distal end of the body of the osteotome.

There is also provided a kit for use in surgery, the kit comprising: an osteotome, and a nozzle for a syringe, and wherein: the taper from the distal shoulder towards the distal tip of the body of the nozzle matches the taper from the distal shoulder towards the distal tip of the body of the osteotome.

There is also provided a kit for use in surgery, the kit comprising an osteotome, and/or a kit for use in surgery comprising an osteotome, and: and a nozzle for a syringe, the nozzle for a syringe comprising: a body having a longitudinal axis; the body having a distal end; and the body comprising a distal shoulder extending around an external surface of the body; the distal end of the body extending distally from the distal shoulder, and wherein the distal end of the body tapers in a distal direction from the distal shoulder towards a distal tip along the longitudinal axis and wherein: the length of the distal end of the body of the nozzle matches the length of the distal end of the body of either: the osteotome, or one of the osteotomes in the kit of osteotomes.

There is also provided a kit for use in surgery, the kit comprising an osteotome, and/or a kit for use in surgery comprising an osteotome, and: and a nozzle for a syringe, the nozzle for a syringe comprising: a body having a longitudinal axis; the body having a distal end, and the body comprising a distal shoulder extending around an external surface of the body; the distal end of the body extending distally from the distal shoulder, and wherein the distal end of the body tapers in a distal direction from the distal shoulder towards a distal tip along the longitudinal axis, and wherein: the taper from the distal shoulder towards the distal tip of the body of the nozzle matches the taper from the distal shoulder towards the distal tip of the body of either: the osteotome, or one of the osteotomes in the kit of osteotomes.

When the shape and dimensions of nozzle in a kit match the shape and dimensions of the largest osteotome used to drill an access hole into which the nozzle needs to be inserted, the match between the dimensions of the nozzle and the access hole allows a tight fit between the nozzle and the access hole, which allows increased continuous pressure to be delivered during delivery of the plasma and reduced leakage of plasma back into the mouth.

There is further provided a thumb tab for a plunging a plunger of a syringe, the thumb tab comprising: a base portion for attachment to the plunger; and a resiliently deformable spring element extending from the base portion; wherein the spring element is moveable from a relaxed position to a compressed position in response to a user pressing on the spring element to depress the plunger within the syringe, in use.

The thumb tab beneficially dampens changes in velocity of the plunger as it is plunged in the syringe as a result in variations in the pressure applied to the plunger by a user. When the spring element is in the compressed position variations in the pressure applied to the spring element by a user are dampened by the spring element which in turn promotes a smooth depression of the plunger within the syringe. This is particularly beneficial for applying fluids, for example blood plasma, to a target treatment site where pressure spikes in the fluid may damage the target treatment site.

Optionally, the spring element may be a deformable tab. For example, the deformable tab may be a plastics tab extending from the base portion of the thumb tab. The deformable tab may comprise a flat surface upon which a user may position their thumb to depress the plunger within the syringe.

Optionally, the deformable tab may be connected to a front edge, or distal edge, of the base portion. The spring element may extend generally upwardly, at least initially, away from the base portion. For example, the deformable tab may extend at an angle of about <NUM> degrees or more away from the front edge of the base portion. As such, the deformable tab may extend generally upwardly and in a proximal direction relative to the front edge of the base portion.

Optionally, the deformable tab may extend along an arcuate path from the base portion. For example, the arcuate path may extend in an upward and proximal direction relative to the front edge of the base portion. The deformable tab may be curved. Furthermore, a proximal end of the deformable tab may be generally flat to define a surface upon which the user may apply a force with their thumb to move the tab from the relaxed position to the compressed position in order to depress the plunger within the syringe.

The deformable tab may comprise an aperture. The aperture may be a slot extending through the deformable tab. This is beneficial as the dimensions of the aperture may be varied to control the stiffness of the deformable tab.

Optionally, the thumb tab may be integrally formed with the plunger. For example, the base portion of the thumb tab may be integrally formed with a plunger.

Optionally, the thumb tab may comprise an attachment formation on an underside of the base portion for securing the thumb tab to the plunger. As such, the thumb tab may be clipped on or secured to conventional plungers. This is beneficial as conventional plungers and syringes may be fitted with the thumb tab to promote smooth plunging of the plunger for applications where care should be taken to avoid pressure spikes in the fluid being expelled from the syringe.

The attachment formation may comprise an attachment flange coupled to the base portion. The attachment flange may be coupled to a front edge of the base portion. Furthermore, the attachment flange may extend in a proximal direction relative to the front edge to define a slot between the base portion and the attachment flange. The slot may be dimensioned so as to at least partially accommodate the top of a plunger within the slot. The slot may be dimensioned such that there is a push fit or press fit between the slot and the top of the plunger to retain the thumb attachment on the plunger.

Optionally, the attachment flange may comprise a notch on a proximal side of the attachment flange for at least partially accommodating the shaft of the plunger. A longitudinally extending recess may be positioned in a base of the notch for accommodating part of the shaft of the plunger. This is particularly beneficial for plungers having a shaft with a cross shaped profile.

Optionally, the spring element may comprise at least one grip formations for providing grip to a user of the thumb tab.

Optionally, the base portion may comprise an upwardly extending lip for inhibiting movement of the spring element. The lip may extend upwardly from a rear edge of the base portion. The lip beneficially inhibits movement of the spring element which in turn may improve the control of the plunger as a user applies a force to the spring element to depress the plunger.

There is further provided a plunger for a syringe wherein the plunger comprises a thumb tab.

There is further provided a syringe comprising a plunger.

There is further provided: a method of augmenting bone at a target treatment site on the patient's maxillary bone, the method comprising: inserting a nozzle into an access hole in the maxillary bone at the target treatment site; forming a seal between the nozzle and the maxillary bone; and distributing platelet rich blood plasma at the target treatment site through the access hole; wherein distributing the platelet rich blood plasma comprises lifting the patient's maxillary sinus lining off the maxillary bone to create a cavity and filling the cavity with the platelet rich blood plasma.

Optionally, lifting the patient's maxillary sinus may comprise applying a positive pressure to the sinus lining by injecting the platelet rich blood plasma at the target treatment site to cause the sinus lining to lift off the maxillary bone. Injecting the platelet rich blood plasma at the target treatment site may cause tenting of the maxillary sinus lining.

Optionally, the method may be preceded by drilling the access hole in the maxillary sinus. The dental surgeon may open or lift a flap in the gum to access the maxillary bone before drilling the access hole. The access hole beneficially allows the nozzle to be positioned so as to distribute blood plasma at the target treatment site.

There is further provided a method of drilling an access hole in the maxillary bone at the target treatment site, the method comprising:.

Optionally, the method of drilling an access hole in the maxillary bone at the target treatment site further comprises:.

and, the distance between the distal shoulder towards the distal tip along the longitudinal axis of the second osteotome being greater than the distance between the distal shoulder towards the distal tip along the longitudinal axis of the first osteotome.

Optionally, the method of drilling an access hole in the maxillary bone at the target treatment site further comprises: repeating the step carried out by the second osteotome with one or more further osteotomes that have a distance between the distal shoulder towards the distal tip along the longitudinal axis of the osteotome being greater than the distance between the distal shoulder towards the distal tip along the longitudinal axis of the first or the second osteotome.

When the shape and dimensions of the nozzle inserted into an access hole drilled by an osteotome correspond to the shape of the largest osteotome used to drill the said access hole, the match between the dimensions of the nozzle sand the access hole allows a tight fit between the nozzle and the access hole, which allows increased continuous pressure to be delivered during delivery of the plasma and reduced leakage of plasma back into the mouth.

Optionally, distributing the platelet rich blood plasma may comprise ejecting the blood plasma from a plurality of exit gates in the nozzle. The exit gates may be spaced circumferentially around a distal end of the nozzle. Optionally, forming the seal may comprise pressing a distal shoulder of the nozzle against the maxillary bone. Beneficially, the seal between the nozzle and the maxillary bone allows a pressure to gradually build at the target treatment site as the platelet rich blood plasma is expelled from the nozzle. This in turn causes the maxillary sinus lining to lift off the maxillary bone.

There is also provided a method of augmenting bone at a target treatment site, the method comprising: inserting a nozzle into an access hole in a bone at the target treatment site; forming a seal between the nozzle and the bone; and distributing platelet rich blood plasma at the target treatment site through the access hole.

This method of augmenting bone may be used, for example, to augment bone at a target treatment site on a patient's skull. The nozzle may be inserted into an access hole in the patient's skull and platelet rich blood plasma may be distributed at the target treatment site using the nozzle. The seal formed between the bone and the nozzle beneficially ensures the platelet rich blood plasma is distributed at the target treatment site. The method may be used with the nozzle and or thumb tab.

There is also provided a method of expelling a fluid, such as platelet rich blood plasma from a syringe wherein the syringe comprises a plunger having a deformable thumb tab, the method comprising: applying a plunging force to a spring element on the thumb tab; moving the spring element from a relaxed position to a compressed position in response to applying the plunging force to the spring element; and plunging the plunger within the syringe to expel the fluid from the syringe whilst the spring element is in the compressed position.

Within the scope of this application it is expressly intended that the various aspects, embodiments, examples and alternatives set out in the preceding paragraphs, and/or in the following description and drawings, and in particular the individual features thereof, may be taken independently or in any combination.

In general terms there is provided a nozzle for a syringe and to a thumb tab for a plunger for use with a syringe for delivering blood plasma to a target treatment site within a sinus cavity of a patient's mouth, and an osteotome for drilling an access hole to a sinus cavity of a patient's mouth, suitable for receiving a nozzle of a syringe. The nozzle may be fitted to a syringe such that fluid, for example blood plasma, can be delivered to a target treatment site within the patient's mouth. The nozzle comprises a body having an inlet for receiving blood plasma from the syringe and an outlet for delivering the blood plasma to the target treatment site within the sinus cavity of the patient. The outlet of the nozzle comprises an outlet aperture located on a distal tip of the nozzle aligned with a longitudinal axis of the nozzle and a plurality of exit gates positioned circumferentially around the distal end of the nozzle.

The nozzle beneficially allows blood plasma to be dispersed evenly at the target treatment site through the outlet aperture and exit gates. Dispersing the blood plasma evenly at the target treatment site is beneficial as dispersed flow from the outlet reduces pressure spikes or pressure points on the sinus lining membrane which may cause the sinus lining membrane to burst or rupture.

Reference will firstly be made to <FIG> which shows a schematic sectional view of a patient's gum <NUM> and maxillary bone <NUM> at a target treatment site <NUM> within a patient's mouth. The target treatment site <NUM> may be a site where a dental implant is to be fitted and augmentation of the maxillary bone <NUM> is required prior to fitting the implant. For example, the target treatment site <NUM> may be a region of the maxillary bone <NUM> where augmentation of the bone <NUM> is required in order to grow sufficient bone to allow a dental implant to be fitted at the target treatment site <NUM>. The maxillary sinus membrane <NUM> is positioned above the maxillary bone <NUM> and extends across the target treatment site <NUM>. As shown in <FIG> the maxillary sinus lining membrane <NUM> extends over the maxillary bone <NUM>.

In the example shown the patient does not have any teeth adjacent the target treatment site <NUM> but the skilled reader will understand that in some instances the patient may have teeth on one or both sides of the target treatment site <NUM>. The skilled reader will understand that the target treatment site may also be remote from the proposed dental implant site. In this instance the access hole is not sealed with the placement of a dental implant but a non-resorbable membrane is placed over the access hole (osteotomy) during the healing phase. This non-resorbable membrane will be removed once healing is complete, usually <NUM> - <NUM> months after the initial treatment.

To access the target treatment site <NUM> a dentist may initially anaesthetise the patient and create a flap (not shown) within the patient's gum <NUM> to expose and access the maxillary bone14. A hole may subsequently be drilled in the maxillary bone <NUM> such that platelet rich blood plasma may be delivered to the target treatment site <NUM> via the hole in the bone <NUM>.

Turning now to <FIG> a nozzle <NUM> for a syringe is shown. The syringe nozzle <NUM> is configured to distribute platelet rich blood plasma at the target treatment site <NUM> within the patient's mouth. The syringe nozzle <NUM> comprises a body <NUM> having a longitudinally extending axis <NUM>. The longitudinal axis <NUM> extends between a proximal end <NUM> of the body <NUM> and a distal end <NUM> of the body <NUM>. A passage <NUM> for conveying blood plasma from the syringe to the target treatment site <NUM> extends through the body <NUM> along the longitudinal axis <NUM>. As such, the passage <NUM> extends between and fluidly connects the proximal end <NUM> to the distal end <NUM> of the nozzle <NUM> through the body <NUM>.

The proximal end <NUM> of the nozzle <NUM> comprises an inlet <NUM> for receiving blood plasma from a syringe (not shown in <FIG>). Furthermore, the outlet of the nozzle <NUM> is located at the distal end <NUM> of the nozzle <NUM> and comprises an outlet aperture <NUM> and radially extending exit gates <NUM>. The outlet aperture <NUM> and exit gates <NUM> are positioned at the distal end <NUM> of the nozzle <NUM> for delivering and distributing blood plasma at the target site <NUM> of the patient. The passage <NUM> extends from the inlet <NUM> to the outlet aperture <NUM> such that the inlet aperture <NUM>, outlet aperture <NUM> and exit gates <NUM> are fluidly connected via the passage <NUM>.

As shown in <FIG> the body <NUM> of the nozzle <NUM> comprises a central body portion <NUM>. The distal end <NUM> and the proximal end <NUM> extend in distal and proximal directions respectively from the central body portion <NUM>. As shown in <FIG> the distal end <NUM> of the nozzle <NUM> is frustoconical in shape with a generally planar distal tip <NUM>. The frustoconical distal end <NUM> extends and tapers distally from a distal shoulder <NUM> of the central body portion <NUM>. The side wall <NUM> of the distal end <NUM> tapers in a distal direction along the longitudinal axis <NUM> from the shoulder <NUM> towards the distal tip <NUM>.

Four exit gates <NUM> are arranged circumferentially around the distal end <NUM> of the nozzle <NUM> such that the exit gates <NUM> extend radially from the passage <NUM> and longitudinal axis <NUM>, through the side wall <NUM> of the distal end <NUM>. Each exit gate <NUM> is generally square in shape. This is beneficial as the square shape of the exit gates <NUM> maximises the cross-sectional area of each gate <NUM> which in turn helps to promote a uniform distribution and smooth flow from each gate <NUM> thereby reducing the chance of a pressure spike in the fluid rupturing or tearing the sinus lining membrane.

Furthermore, the distally tapering side wall <NUM> and the position of the exit gates <NUM> on the side wall <NUM> allow the nozzle <NUM> to be used in situations where the bone <NUM> is thicker than the length of the distal end <NUM>. In this scenario the tapering distal end <NUM> provides clearance between the exit gates <NUM> and the bone <NUM> such that blood plasma may still be distributed at the target treatment site <NUM>.

Furthermore, each exit gate <NUM> is tapered such that the cross-sectional area of each exit gate <NUM> increases from the passage <NUM> towards the outer surface of the side wall <NUM>. This is beneficial as the increasing cross-sectional area of the exit gates <NUM> reduces the velocity of fluid being expelled from the exit gate <NUM> which in turn reduces the resultant pressure on the maxillary sinus <NUM> resulting from blood plasma exiting the exit gates <NUM>.

The outlet aperture <NUM> is positioned on, and extends through, the distal tip <NUM> of the nozzle <NUM> such that the outlet aperture <NUM> is concentrically aligned with the longitudinal axis <NUM>. The passage <NUM> extends through the distal end <NUM> of the nozzle <NUM> such that the outlet aperture <NUM> and exit gates <NUM> are in fluid communication with the passage <NUM>. The outlet aperture <NUM> may be a circular aperture having a diameter of between about <NUM> and <NUM>. The relatively small diameter outlet aperture <NUM> beneficially reduces the flow of material from the outlet aperture <NUM> thereby reducing the chance of the maxillary sinus lining <NUM> being ruptured by pressure spikes in blood plasma being expelled from the outlet aperture <NUM>.

The central body portion <NUM> comprises a distal shoulder <NUM> and a proximal shoulder <NUM>. The distal and proximal shoulders <NUM>, <NUM> extend around the distal and proximal ends <NUM>, <NUM> of the central body portion <NUM>. This is beneficial as the distal shoulder <NUM> may engage and rest upon the patient's gum <NUM> or maxillary bone <NUM> when the nozzle <NUM> is being used to deliver blood plasma to the target treatment site <NUM>. As such, the distal shoulder <NUM> may form a seal between the nozzle <NUM> and the gum <NUM> or maxillary bone <NUM> as is discussed in further detail below. Furthermore, the proximal shoulder <NUM> may act as a stop for a flexible tube or hose connecting the nozzle <NUM> to a syringe. For example, a hose may be pushed over the proximal end <NUM> such that it abuts and seals against the proximal shoulder <NUM>.

The central body portion <NUM> tapers in a proximal direction along the longitudinal axis <NUM> from the distal shoulder <NUM> towards the proximal shoulder <NUM>. As such, the diameter of the central body portion <NUM> is greater at the distal shoulder <NUM> compared to the proximal shoulder <NUM>. This is beneficial as the proximally tapering central body portion <NUM> provides a surface that a dentist may grip when using the nozzle <NUM>. The central body portion <NUM> may be textured to improve grip. Furthermore, the tapering central body portion <NUM> prevents the dentist's fingers from sliding down the nozzle <NUM>, in use, in a distal direction towards the target treatment site <NUM>. This is beneficial as the dentist may push or urge the nozzle <NUM> towards the hole in the maxillary bone <NUM> to ensure a seal is created between the distal shoulder <NUM> and the maxillary bone <NUM> or gum <NUM>.

As best viewed in <FIG>, the proximal end <NUM> of the nozzle <NUM> is frustoconical shaped and comprises a generally planar proximal tip <NUM>. The proximal end <NUM> of the nozzle <NUM> extends and tapers in a proximal direction along the longitudinal axis <NUM> from the proximal shoulder <NUM> of the central body portion <NUM> to a proximal tip <NUM>. The passage <NUM> extends along the longitudinal axis <NUM> through the proximal end <NUM> and terminates at the inlet <NUM> on the proximal tip <NUM>. The inlet <NUM> is positioned on the proximal tip <NUM> and is aligned concentrically with the central longitudinal axis <NUM> and thus also the outlet aperture <NUM>.

Turning now to <FIG> the nozzle <NUM> is shown schematically at the target treatment site <NUM> within the patient's mouth. To position the nozzle <NUM> at the target treatment site <NUM> the dentist may open a flap (not shown) in the patient's gum <NUM> at the target treatment site <NUM> where augmentation of the maxillary bone <NUM> is required. A small hole <NUM>, for example between about <NUM> - <NUM> diameter is drilled in the maxillary bone <NUM> to gain access to the sinus membrane <NUM> and the distal end <NUM> of the nozzle <NUM> may be at least partially received within the hole <NUM>.

When the nozzle <NUM> is positioned at the target treatment site <NUM> the distal shoulder <NUM> abuts the gum <NUM> and/or maxillary bone <NUM> to form a seal between the nozzle <NUM> and the maxillary bone <NUM>. The distal end <NUM> is positioned at the target treatment site <NUM> such that the distal tip <NUM> protrudes through the hole <NUM> in the maxillary bone <NUM> and the distal end <NUM> is received within the hole <NUM>.

The platelet rich blood plasma is expelled through the outlet aperture <NUM> and exit gates <NUM> such that the blood plasma is distributed evenly at the target treatment site <NUM>. As the platelet rich blood plasma is expelled from the outlet of the nozzle <NUM> the build-up of pressure from the blood plasma causes the maxillary sinus membrane <NUM> to lift off the maxillary bone <NUM> as shown in <FIG> to create a cavity <NUM>. The seal between the distal shoulder <NUM> and the maxillary bone <NUM> causes an increase in pressure within the cavity <NUM> as the blood plasma is injected to the target treatment site <NUM>. The increase in pressure causes the maxillary sinus membrane <NUM> to lift off the bone <NUM> to create the cavity <NUM> which is subsequently filled by platelet rich blood plasma. The nozzle <NUM> is then removed from the patient's mouth leaving the blood plasma in the target treatment site <NUM>. The access hole is then sealed with a dental implant or a non-resorbable membrane and the gum sutured back in place, over the dental implant or non-resorbable membrane.

Turning now to <FIG> a thumb tab <NUM> for plunging a plunger of a syringe is shown. In general terms the thumb tab <NUM> comprises a base portion <NUM> for attachment to a plunger of a syringe and a deformable tab or spring element <NUM> extending from the base portion <NUM> for depressing the plunger of the syringe. The base portion <NUM> may be integral with a plunger or the base portion <NUM> may comprise an attachment formation <NUM> for securing the thumb tab <NUM> to a plunger of a conventional syringe.

The spring element <NUM> of the thumb tab <NUM> is resiliently deformable such that when a user of the syringe depresses the plunger by pressing on the spring element <NUM> of the thumb tab <NUM> the spring element <NUM> is compressed such that it bends or flexes. The spring element <NUM> may be moved from a relaxed position to a compressed or loaded position, in response to a user pressing on the thumb tab <NUM> to depress the plunger. The spring element further comprises a series of gripping formations <NUM> in the form of laterally extending ridges on an upper surface of the spring element <NUM>. The gripping formations <NUM> provide a surface upon which a user may apply a plunging force with their thumb to the spring element <NUM>.

When the spring element <NUM> is in the compressed position the spring element <NUM> may act to dampen fluctuations in the velocity of the depression of the plunger caused by variations in the plunging force applied to the plunger by a user. This in turn promotes a smoother depression of the plunger and thus reduces pressure spikes in the fluid expelled from the syringe. This is particularly beneficial for applying platelet rich blood plasma to a target treatment site <NUM> within a sinus cavity <NUM> as spikes in the pressure of the fluid may rupture the delicate maxillary sinus membrane <NUM>.

<FIG> shows a side view of the thumb tab <NUM> in the relaxed position. As shown in <FIG> the side profile of the spring element <NUM> is generally arcuate or curved. The spring element <NUM> extends generally upwardly away from a front edge <NUM> of the base portion <NUM> initially before curving in a proximal direction relative to the front edge <NUM> of the thumb tab <NUM>.

<FIG> shows a side view of the thumb tab <NUM> in the compressed position. In <FIG> the spring element <NUM> of the thumb tab <NUM> has been depressed towards the base portion <NUM> as would be the case when a user of the syringe applied a load on the thumb tab <NUM> to depress a plunger. When in the compressed position the force applied to the spring element <NUM> is balanced by the reactant force from the spring element <NUM> and the force associated with depressing the plunger. Any variations in the pressure applied to the plunger by the user may be dampened by movements in the spring element <NUM> such that the force applied to the plunger is substantially constant thereby reducing pressure spikes in the blood plasma exiting the syringe.

As best viewed in <FIG>, an aperture <NUM> is positioned within the spring element <NUM>. The aperture <NUM> may be a slot extending upwardly from the front edge <NUM> of the base portion <NUM> through the spring element <NUM>. The size of the aperture <NUM>, in particular the width of the aperture <NUM>, may be varied to alter the stiffness of the spring element <NUM>. For example, if a relatively stiff spring element <NUM> is required the aperture may be relatively narrow, for example <NUM> - <NUM> wide or the aperture <NUM> may be removed entirely. Where a more flexible spring element <NUM> is required the width and length of the aperture <NUM> may be increased. For example, the width of the aperture <NUM> may be <NUM> or greater.

The aperture <NUM> beneficially allows the thumb tab <NUM> to be tuned to be used with syringes of differing volumes. For example, a syringe with a relatively large volume may require a stiffer spring element <NUM> than a corresponding syringe having a smaller volume.

Turning now to <FIG> an underside perspective view of the thumb tab <NUM> is shown. The base portion <NUM> comprises an attachment formation <NUM> for securing the thumb tab <NUM> to a plunger of a syringe. The attachment formation <NUM> is configured to allow the thumb tab <NUM> to be clipped to the plunger of a conventional syringe to dampen pressure spikes in the fluid being expelled from the syringe.

As shown in <FIG> the attachment formation <NUM> may comprise an attachment flange <NUM> secured to the base portion <NUM> at the front edge <NUM> of the base portion <NUM>. The attachment flange <NUM> extends substantially parallel to the base portion <NUM> in a proximal direction from the front edge <NUM>. A slot <NUM> is defined between the underside of the base portion <NUM> and an upper side of the attachment flange <NUM>. As such the slot <NUM> extends generally parallel to a plane of the base portion <NUM>. The slot <NUM> is configured to at least partially receive the top of a plunger as shown in <FIG>. The thumb attachment <NUM> may be secured to the plunger by sliding the attachment flange <NUM> over the top of a plunger such that the top of the plunger is at least partially received within the slot <NUM>.

The attachment flange <NUM> comprises a notch <NUM> on the proximal side <NUM> of the flange <NUM> for accommodating the shaft of the plunger. The shaft of the plunger typically comprises a cross-shaped profile and the notch <NUM> is dimensioned to at least partially the cross-shaped shaft of the plunger. The notch <NUM> further comprises a recess <NUM> in the base <NUM> of the notch <NUM>. The recess <NUM> is a longitudinally extending recess or slot in the base <NUM> of the notch <NUM> for at least partially receiving one of the arms of the cross-shaped shaft of the plunger.

<FIG> shows the thumb tab <NUM>. As shown in <FIG> the thumb tab <NUM> comprises an upwardly extending lip <NUM>. The lip <NUM> serves as an abutment or stop to limit the movement of the spring element <NUM>. Inhibiting the compression of the spring element <NUM> is beneficial as it improves control when plunging the plunger. The lip <NUM> is connected to and extends upwardly from a rear edge <NUM> the base portion <NUM>.

When the spring element <NUM> is in the compressed position the spring element <NUM> typically does not contact the lip <NUM>. However, if there was, for example, a blockage that prevented fluid exiting the nozzle <NUM> the spring element may be further deformed and contact the lip <NUM>. Upon contact with the lip <NUM> the dental surgeon using the thumb tab <NUM> may realise that there is a blockage and stop applying pressure to the spring element <NUM>. This beneficially prevents any pressure spikes in the fluid being distributed by the nozzle <NUM>.

Turning now to <FIG> there is shown a syringe <NUM> and plunger <NUM>. The distal tip of the syringe <NUM> comprises the syringe nozzle <NUM> and the plunger <NUM> comprises the thumb tab <NUM>.

As shown in <FIG>, the nozzle <NUM> is connected to the distal tip of the syringe <NUM> by a flexible tube <NUM>. The flexible tube <NUM> may be made from a flexible rubber material, plastics material or the like. The flexible tube <NUM> beneficially allows the position of the nozzle <NUM> relative to the syringe <NUM> to be controlled by a dentist. For example, when the nozzle <NUM> is positioned at a target treatment site <NUM> the dentist may position the nozzle <NUM> such that it extends generally perpendicularly relative to the syringe <NUM> to ensure that the nozzle <NUM> is correctly positioned and sealed to the maxillary bone <NUM> at the target treatment site <NUM>.

The thumb attachment <NUM> may be clipped to the circular top <NUM> of the plunger <NUM> via the attachment formation <NUM>. As such, a user of the syringe <NUM> may press on the thumb tab <NUM> to depress the plunger <NUM> and expel platelet rich blood plasma from the nozzle <NUM> to the target treatment site.

Whilst the above shows the thumb tab <NUM> as a component that may be clipped to the top <NUM> of the plunger <NUM>, the thumb tab <NUM> may instead be an integral part of the top <NUM> of the plunger <NUM>. <FIG> show side views of plungers <NUM> where the thumb tab <NUM> is integral with or integrally formed with the plunger <NUM>.

Turning now to <FIG>, the syringe <NUM> of <FIG> is shown in the hands of a user, for example, in the hands of a dental surgeon. As shown in <FIG>, the user's right hand <NUM> may be used to depress the plunger <NUM> by placing the user's right-hand thumb on the thumb tab <NUM>. The user may then apply a force to the thumb tab which will compress the thumb tab <NUM> to the compressed configuration and also depress the plunger <NUM> within the syringe <NUM>. The user may continue to apply the downward pressure on the thumb tab <NUM> to expel the fluid within the syringe from the nozzle <NUM>. Any fluctuations in the pressure applied to the thumb tab <NUM> by the user will be dampened by the spring element <NUM> thereby promoting a constant depression velocity of the plunger <NUM> and thus pressure spikes in the fluid expelled from the nozzle <NUM> will be minimised.

Furthermore, as shown in <FIG> the user may use their other hand, in this case their left hand, to control the position of the nozzle <NUM> relative to the syringe <NUM>. The user may grip the central body portion <NUM> of the nozzle <NUM> to grip the nozzle <NUM> and control the position of the nozzle <NUM> by manipulating the flexible tube <NUM>. The skilled reader will understand that the user may alternatively use their left hand to depress the plunger <NUM> and to use their right hand <NUM> to hold and control the position of the nozzle <NUM>.

<FIG> shows an osteotome <NUM>. Osteotome <NUM> is configured to drill a hole <NUM> enabling a nozzle to access a treatment site <NUM>. Osteotome <NUM> comprises a body <NUM> having a longitudinal axis <NUM>; the body having a distal end <NUM>, and the body <NUM> comprising a distal shoulder <NUM> extending around an external surface of the body; the distal end <NUM> of the body extending distally from the distal shoulder <NUM>, and wherein the distal end <NUM> of the body tapers in a distal direction from the distal shoulder <NUM> towards a distal tip <NUM> along the longitudinal axis.

Distal end <NUM> of the body <NUM> of the osteotome <NUM> is frustoconical such that the distal tip <NUM> is generally planar. The distal tip of the osteotome being generally planar may provide the advantage that a planar tip is less likely to damage the Schneiderian Membrane, if the osteotome is used to drill through (or at least partially through) a patient's maxillary bone.

When the osteotome <NUM> has drilled a hole <NUM> as far as possible towards the target treatment site <NUM> the distal shoulder <NUM> of the osteotome <NUM> will abut the gum <NUM> and/or maxillary bone <NUM> to prevent the distal tip <NUM> of the osteotome <NUM> drilling any further through the maxillary bone <NUM>. Each osteotome therefore has a maximum drilling depth that it can reach. In order to increase the depth of a hole <NUM> in the maxillary bone of a patient, it is preferable to then use another osteotome 220a also having a body 222a having a longitudinal axis 224a; the body having a distal end 228a, and the body 222a comprising a distal shoulder 230a extending around an external surface of the body; the distal end 228a of the body extending distally from the distal shoulder 230a, and wherein the distal end 228a of the body tapers in a distal direction from the distal shoulder 230a towards a distal tip 236a along the longitudinal axis.

In osteotome 220a, the distance between distal shoulder 230a and distal tip 236a along the longitudinal axis 224a is longer than the distance between distal shoulder <NUM> and distal tip <NUM> along the longitudinal axis <NUM> of first osteotome <NUM>. This allows osteotome 220a to drill deeper into the maxillary bone of a patient than osteotome <NUM> can, before the shoulder 230a abuts the maxillary bone of the patient and prevents osteotome 220a from drilling any deeper.

If it is necessary to drill the hole <NUM> in the maxillary bone deeper still in order to reach the treatment site <NUM>, it is preferable to use a further osteotome 220b. Osteotome 220b having a distal shoulder 230b and distal tip 236b, and the distance between distal shoulder 230b and distal tip 236b being greater than the distances between the distal shoulder <NUM>, 230a and distal tip <NUM>, 236a in osteotome <NUM> or in 220a. This therefore allows a surgeon to drill deeper into the maxillary bone of a patient than osteotome <NUM> or 220a can, before the shoulder 230b abuts the maxillary bone of the patient and prevents osteotome 220b from drilling any deeper.

Providing a kit of osteotomes with different distances between their respective distal shoulders and distal tips allow a dentist/surgeon to select an osteotome that will only slightly increase the depth of the current hole <NUM>. Providing a selection of osteotomes allows the surgeon to carefully, and very incrementally, increase the depth of hole <NUM> to gain access to treatment site <NUM>, while keeping the odds low that the osteotome will protrude too far through the bone, meaning that the odds of damage to the Schneiderian Membrane of the patient decrease. <FIG> shows a kit of osteotomes <NUM>, 220a, 220b, 220c, 220d, and 220e, having respective distal ends <NUM>, 228a, 228b, 228c, 228d, and 228e, their respective distal ends having respective distal shoulders <NUM>, 230a, 230b, 230c, 230d, and 230e, and respective distal tips <NUM>, 236a, 236b, 236c, 236d, and 236e. As shown in <FIG>, the distances between the respective distal shoulders <NUM>, 230a, 230b, 230c, 230d, and 230e, and respective distal tips <NUM>, 236a, 236b, 236c, 236d, and 236e of osteotomes <NUM>, 220a, 220b, 220c, 220d, and 220e vary, enabling a surgeon to choose the most appropriate osteotome for the stage of hole drilling that they are at.

Any of the osteotomes can be used with a handle such as osteotome handle <NUM>. osteotome handle <NUM> has a grip <NUM> for a user to grip, and a connector <NUM> to which an osteotome <NUM>, 220a, 220b, 220c, 220d, or 220e may be attached. Any osteotome to be used with handle <NUM> may be provided with a connector <NUM> configured to connect to connector <NUM>.

<FIG> outlines a method of distributing platelet enriched blood plasma at a target treatment site <NUM> within a patient's mouth using the nozzle <NUM>. In Step <NUM> the dental surgeon drills through the maxillary bone <NUM> into the floor of the maxillary sinus cavity, using an osteotome. Drilling through the maxillary bone <NUM> exposes the maxillary sinus <NUM> and provides access to the sinus membrane. The hole <NUM> drilled through the maxillary bone <NUM> may be between about <NUM> and <NUM> in diameter. For example, a dentist may use a <NUM> diameter drill to create the hole <NUM> in the maxillary bone <NUM>. Prior to Step <NUM> the dentist may apply local anaesthetic to the target treatment area <NUM> and open a gum flap in the patient's gum <NUM> to provide access to the maxillary bone <NUM> where the hole <NUM> is to be drilled.

In Step <NUM> the distal end <NUM> of the nozzle <NUM> is inserted into the hole drilled into the maxillary bone <NUM>. The distal end <NUM> of the nozzle <NUM> is advanced into the hole until the distal shoulder <NUM> of the nozzle <NUM> abuts the maxillary bone <NUM> or gum <NUM> around the perimeter of the hole <NUM>. The distal shoulder <NUM> forms a seal between the nozzle <NUM> and the maxillary bone <NUM> thereby preventing any blood plasma leaking out from the target treatment site <NUM> when the blood plasma is being distributed by the nozzle <NUM> at the target treatment site <NUM>. Furthermore, the distal shoulder <NUM> may be used to control or inhibit the depth of penetration of the distal end <NUM> of the nozzle <NUM> into the sinus cavity <NUM> thereby stopping the dentist inadvertently tearing the sinus lining <NUM> with the distal end <NUM> of the nozzle <NUM>.

It will be appreciated that using a nozzle having a distal end that corresponds in shape/size to the largest (final) osteotome used to drill the hole <NUM> will result in a close fit between the nozzle and the hole <NUM>. Having a tight fit between the nozzle and the hole drilled by the osteotome allows increased continuous pressure to be delivered during delivery of the plasma and reduced leakage of plasma back into the mouth in step <NUM>.

In Step <NUM> the platelet rich blood plasma is injected or distributed at the target treatment site <NUM> via the nozzle <NUM>. When the blood plasma is initially injected a pressure builds within the sinus cavity <NUM> at the target treatment site <NUM> as a result of the blood plasma being injected and also the seal formed by the distal shoulder <NUM>. As the pressure at the target site builds the maxillary sinus lining or membrane <NUM> lifts off the maxillary bone <NUM> as shown in <FIG> to create a cavity <NUM>. As such, tenting or lifting of the maxillary sinus <NUM> lining occurs at the target treatment site <NUM> and platelet rich blood plasma fills the cavity <NUM> created between the maxillary bone <NUM> and the maxillary sinus <NUM>.

In Step <NUM> blood plasma is continued to be distributed at the target treatment site <NUM> such that the sinus cavity <NUM> defined between the maxillary bone <NUM> and the sinus lining <NUM> that has been lifted off the maxillary bone <NUM> is filled with the platelet rich blood plasma. Distributing the blood plasma at the target treatment site <NUM> may comprise expelling the blood plasma in a direction aligned with the longitudinal axis <NUM> and a further direction that is generally perpendicular to the longitudinal axis <NUM>. For example, the blood plasma may be expelled from the outlet aperture <NUM> and one or more of the exit gates <NUM>.

When the blood plasma has been distributed at the target treatment site <NUM> the nozzle <NUM> may be removed from the hole <NUM> in the maxillary bone <NUM> and the flap in the gum <NUM> may be closed. The platelet rich blood plasma at the target treatment site <NUM> will promote growth and augmentation of the maxillary bone <NUM> such that a dental implant may be fitted at the target treatment site <NUM>.

A kit including a range of sizes of osteotomes and nozzles enables a surgeon to test whether the treatment site <NUM> has been reached in a less invasive way than previous equipment allowed. One further advantage of using a set of osteotomes with varying distal end sizes/shapes and a set of nozzles with correspondingly varying distal end sizes/shapes is that the surgeon can, non-invasively, test whether they have successfully reached the treatment area <NUM> by removing an osteotome, inserting the correspondingly sized/shaped nozzle (attached to a syringe and filled with blood plasma) and gently.

Applying pressure to the plunger of the syringe. If the plunger has not started to depress within <NUM>-<NUM> seconds it is unlikely that the hole <NUM> has fractured up through the floor of the sinus yet. Continuing to attempt to force the plasma through the nozzle could result in perforation of the sinus membrane and failure of the technique (on this attempt). To remedy this the next of osteotome is chosen, the hole <NUM> is extended, then the corresponding nozzle is used to reattempt to deliver plasma to the site <NUM>. These steps are repeated, until it is possible to deliver the plasma gel into the sinus in a controlled manner.

Claim 1:
A nozzle (<NUM>) for a syringe (<NUM>) for distributing blood plasma at a target treatment site (<NUM>) within a patient's mouth, the nozzle (<NUM>) comprising:
a body (<NUM>) having a passage (<NUM>) extending through the body (<NUM>) along a longitudinal axis (<NUM>) of the body (<NUM>), the passage (<NUM>) extending from a proximal end (<NUM>) to a distal end (<NUM>) of the body (<NUM>);
an inlet (<NUM>) to the passage (<NUM>) at the proximal end (<NUM>) for receiving blood plasma from the syringe (<NUM>);
an outlet from the passage (<NUM>) at the distal end (<NUM>) for distributing blood plasma at the target treatment site (<NUM>), wherein the outlet comprises an outlet aperture (<NUM>) located on a distal tip (<NUM>) of the nozzle (<NUM>); and
at least one exit gate (<NUM>) extending from the passage (<NUM>) through the distal end (<NUM>) of the body (<NUM>), characterized in that the at least one exit gate (<NUM>) tapers outwardly from the passage (<NUM>).