the apparatus is a flexible disposable laser fiber tip 12 capable of three - dimensional side - firing or radial - firing along its working length . see fig1 ) the working length is defined to mean the portion of the fiber that emits laser energy for the purpose of doing work . it may include an end - firing tip , radial or side - firing emissions , or a combination , thereof . the actual working length is determined by the modifications to the protective and reflective coverings surrounding the transmission fiber . it is anticipated that the diameter of the working fiber , including coverings , shall have an external diameter of about 200 to about 800 microns but may be smaller as manufacturing techniques allow . further , the working fiber may be parallel or , alternatively , may have either a fixed or progressively percentage change taper over its working length . clinical laser apparatuses will embody different working lengths and sleeve configurations to accommodate the particular requirements of clinical needs . the control of the energy release along the active tip is accomplished in different ways to achieve preferred levels of energy release as subsequently described . as mentioned above , the present invention relates to a laser apparatus for effective endodontic procedures not previously available . the present inventive apparatus is in part directed to the special laser beam emission tips which provide measured irradiation of selected portions of the primary and secondary channels of the tooth . referring now to fig1 , one embodiment of the tip apparatus is illustrated . tip 12 is connected to a laser source ( shown in fig1 ) via head 11 , later illustrated and described . the source is a conventional laser generator and guide tube , however operating at the unconventional wavelengths described . in preferred embodiments , the laser source is a diode laser . the source is programmed to provide the particular wavelength and irradiation patterns embodied in the described apparatus and methodologies . as illustrated in fig1 , tip 12 includes a fiber optic tip and sheath 16 making up the guide 18 , including the fiber optic bundle 18 a , the cladding 18 b , and an optional protective layer 18 c , for carrying the laser beam to the delivery region 20 of the tip 12 . the upper flexible sheath portion 16 optionally includes a plurality of calibration or depth markings 22 whereby the user may select the depth to which the energy release is delivered to a region disposed in a channel . ( see fig1 a and 10b ) sheath 16 additionally includes color coded firing ( timing ) bands 23 which may indicate relative amounts of energy to be delivered to associated portions of a canal . as further illustrated in fig1 , fiber optic guide 18 a extends into the delivery region 20 whereby emission of the laser beam may be selectively directed to predetermined areas of the primary canals . ( see also fig1 a and 10b ) further , in the described and illustrated embodiments , fig2 illustrates a tip 12 having a working length making up emission area 20 wherein the portion of the guide 18 b extending from sheath 16 incorporates a slotted reflective coating / cladding 18 b ′ allowing a limited release of energy through emission windows 19 . slotted reflective coating / cladding 18 b ′ is in the form of a circumferential opening in the reflective coating / cladding which may exhibit a 360 ° opening or a fraction thereof . workable widths of the openings are from about 0 . 2 mm to about 5 mm and in numbers of bands of from about 1 to about 8 . fig3 illustrates a tip wherein the cladding sheath 18 b extends fully to the delivery region 32 at the end of the tip 12 , wherein the sheath 18 b terminates adjacent the end of the guide 24 however , exposed sufficiently to produce an emission pattern resembling a hemisphere . to accomplish such a pattern , the exposed guide may be on the order of about 0 . 2 mm to about 3 mm including a tapered or rounded aspect at the exposed portion . an emission pattern of this style is particularly useful for procedures including treatment of the most apical primary and secondary anatomy . the embodiment of tip 12 illustrated in fig4 contains a cladding 18 b of sheath 16 extending integrally to the distal end ( delivery region 24 ) such that the emission from guide 18 a is axially out of the end of the guide . an alternative embodiment ( fig7 ) of this style of tip 12 may include a single circumferential window 37 adjacent the distal end 38 , the window 37 having a width of from about 0 . 2 mm to about 3 mm and positioned from about 0 . 1 mm to about 3 mm from the distal end of the tip 38 . an emission pattern from this style of tip is particularly useful for procedures including treatment of the most apical primary and secondary anatomy . the embodiment of tip 32 illustrated in fig5 provides an end - firing tip , wherein the energy irradiation pattern is effectively “ hat - shaped ”. the cladding or sheath 16 surrounding the light guide 18 a to provide a significant end - fired working beam which provides side - firing at the tip 32 as well as axial firing . the embodiment of tip 12 in fig6 incorporates a layered cladding 18 b beginning at a predetermined point approaching the delivery region 20 , where the thickness of the cladding gradually decreases to zero such that the radiated energy gradually increases through the delivery region to a maximum level at the distal end of the tip 24 . in the embodiment of laser tip 12 illustrated in fig7 a , cladding 18 b extends to the tip 32 of the guide and includes a cap 33 over the end of the guide 18 a to block axial release of energy . alternatively , the energy release is through windows or slots 37 , similar to those in fig7 . in the embodiment of an alternative to the tip 12 of fig1 , fig8 illustrates bands of a color coded cladding 23 disposed over guide 18 a to provide depth indication to the user of the tip 12 as it is lowered into a canal . fig9 illustrates an alternative tip 12 wherein the emission window 35 comprises a helical spiral over the emission region 20 to the tip 32 . fig1 illustrates another alternative embodiment of tip 12 , wherein an axial window or slit 35 in the cladding 18 b extends from a predetermined distance from a selected point below the head 11 to the distal end 24 of the tip . this embodiment may incorporate a single or multiple radiation windows , including such as two windows spaced 180 degrees around the sheath 12 , or windows at other uniform ( 120 °, 90 ° locations ) or grouped regions . such as two or three windows within a 45 ° span of the cladding 18 b on sheath 16 . an index marker 26 may be disposed on head 11 to indicate the relative position of the radiation window 19 the method of how energy is measured , controlled and distributed in this application is very important . the energy release is regulated in such a way that the amount of energy released is controlled along a specified part of , or along the entire working length of , the radial - firing part of the fiber as well as at the tip . the configuration of such controls is a function of the intended clinical outcome . it is projected that about 200 joules total energy administered at a wattage of between 0 . 5 to 2 . 0 watts in short increments , their exact time calculated dependent on the wattage , tooth type , length and thickness each followed by an approximate 15 second resting period should be sufficient to assure disinfection of the root canal system without overheating the tooth or surrounding structures . release of energy may be in pulses of specific duration and / or energy level . likewise , the energy may be delivered in patterns of numbers of such pulses a selected pulse levels and duration , as may be particularly effective for certain treatments . the energy formula : [( units of energy released over time )×( the total time of release )= the total amount of energy released into the root canal system ] is both measurable and reproducible and is a function of the time spent in the root canal system with the irradiation turned on less the small allowance for waste energy . it is the specific control and quantification of laser irradiation emissions over time at a specific location that allows assurance of target tissue and cell destruction . this laser irradiation within a prepared canal occurs without concurrent direct vision of the results and must occur without excessive heat buildup that would damage the non - targeted and surrounding tissues including nerves , blood vessels , dentin , periodontal ligament , bone and soft tissue . the present invention , by targeting the water contained within the canal , whether absorbed or contained within unwanted bacteria , diseased tissue or debris , enables the generated heat ( from a low power source ) to be efficiently focused and absorbed by the water , as opposed to the adjacent tooth structure thereby providing a safety factor to tooth destruction . likewise , the ability to focus the heat generation in the contained water promotes the “ wave effect ” of the rush of the heat , gas , bubbles and like products of the more rapid heating than provided by other systems . previous attempts at laser use do not have protocols for precise control of the total energy delivered , location of energy phasing , distribution , or time of delivery , thus they cannot be both predictably efficacious and safe importantly , existing protocols do not address the different energy needs by tooth zone . current protocols are usually done as the random application and movement of a point source for an indeterminate amount of time without strong scientific data supporting the results of these current nonquantifiable approaches . in endodontic treatment , it is the specific control of laser irradiation emissions that allows assurance of target tissue and cell destruction without excessive heat buildup that would damage the non - targeted surrounding tissues . the energy phasing control mechanism may be of several embodiments . in the first embodiment ( fig1 ), a depth gauge 22 is incorporated in a cladding sleeve / sheath around part of the fiber housing that allows for partial irradiation of the root canal in specific treatment zones . the illustrated embodiment illustrates slots 19 in the cladding for the radial , side - firing energy release . at the tip 24 , the cladding stops short of the end of the fiber optic guide 18 permitting 360 ° energy release . when the appropriate amount of energy has been delivered , the tip is manually moved to a new zone indicated by the color - coding on the sleeve / sheath or cladding of the fiber . the zones are typically from about 3 mm to about 7 mm in depth . the markings should be such that a dentist may readily identify the depth of insertion of the tip of the instrument . the cladding , sleeve / sheath and working area of the fiber should be of such a configuration as to prevent the irradiation much beyond 1 . 5 mm inside of the canal proper , particularly at the apical constriction . this protection may be accomplished by the selection of a sleeve of correct length , including such as a telescoping sleeve , a movable sleeve — with or without windows allowing lateral emission of energy , removable sleeves of different lengths , or rings of additional sleeve / sheathing material that can be added to effectively extend the length of the sleeve . this precaution is to prevent stray radiation from injuring surrounding tissues or the clinician , staff , and patient . this shield can be very important in badly broken down teeth where the working portion of the fiber is no longer completely surrounded by tooth structure . another preferred embodiment ( fig9 ) is configured whereby the laser fires 360 degrees horizontally along the entire working length of the fiber via a helical spiral slit 39 in the reflective coating / cladding 18 b originating at the top of the working length of the fiber and ending at the apical tip . such a helical slit shall be between 0 . 05 mm and 1 . 5 mm wide and shall make between one and four complete revolutions around the fiber at the tip . the slit width and helical configuration are not designed to impart either flexibility to the fiber nor change their dimensions on flexion in contradistinction to us2004 / 0038170 and u . s . pat . no . 7 , 040 , 892 . the spiral winding or the slit width may not be uniform along its length allowing for its tighter winding or a wider slit at areas where an increased delivery of energy is required and a looser winding or narrower slit where areas of less energy is required . this configuration allows for a “ three - dimensional or 3 - d lasing ” of the inside of the canal . its energy phasing is controlled both in time and emissions by an electronic device . the device advises the clinician when the appropriate level of energy has been dispensed . in this way the clinical delivery is most efficacious treating one canal at a time in a single step procedure for a prescribed amount of time and without the need for staged movement of the laser tip . such a tip should be inserted to a depth within one mm of the confirmed working length for the canal to be treated . as mentioned earlier , alcohol , chloroform or flammable liquid of any type should not be present at this point . the energy delivered to the selected canal should be approximately 200 joules delivered be delivered at a low wattage as previously described with integral resting periods of about 15 seconds each in which no energy is delivered into the canal to allow the root to cool down . halfway through the treatment interval , an audio alert will sound and the tip should be moved coronally the thickness of one or more color indicator band ( s ). the width and exact dimensions of such band ( s ) shall be calculated in accordance with the energy distribution of the radial slit . by moving the tip the appropriate distance , the reciprocal , untreated areas may be effectively irradiated while allowing the recently treated areas to cool down . the process is then repeated until the total 200 joules has been delivered to the treated canal . to further enhance both the disinfection and cleaning of the canal , one can fill the canal ( s ) with an aqueous solution and activate the tip again at a low wattage of between about 0 . 5 to 2 watts for short periods of time followed by resting periods to take advantage of the photoacoustic effects of this device . the third embodiment ( fig3 ) is a variation of the first embodiment and preferably includes such as electronic time and power controls whereby the clinician moves to a new treatment zone after the appropriate energy for bacteria , etc . kill has been delivered to the first treatment zone . the tip radiating portion is a 360 ° section at tip end 24 wherein the radiation beam extends about 3 to about 7 mm beyond cladding 18 b . in another embodiment ( fig8 ), the color - coding / gradation concept may also be applied directly to the out fiber cladding itself to achieve the same purpose . energy distribution control may be accomplished by any of the four embodiments previously listed . in general , side - firing of a laser fiber may be accomplished by a variety of means ( see fig1 through 6 ). the two methods deemed most feasible for this application include the calculated circumferential scoring of reflective coating / cladding of the fiber which allows a radial or lateral 360 degree distribution of the laser energy from the scored areas . an alternative embodiment for energy distribution is from a tip wherein the reflective coating / cladding thickness is varied from full occlusion to a zero , or nominal , level at the distal end of the tip . such may be achieved by etching of the cladding by dipping the fiber and its reflective coating / cladding into a strong acid and the timed withdrawal of the fiber from that acid yielding a gradient of exposure through the reflective coating / cladding ( fig6 ). in the first energy distribution embodiment related to the fiber scoring , the controlled release of energy is produced in one or more bands along the length of the active fiber tip . the purposes of releasing the laser energy in bands are to first adapt the technique to lasers of low power where there is not enough energy available to produce effective energy release along the whole working length of the fiber tip . second , releasing laser energy in bands also serves to more finely target the energy release in the zones deemed to be of particular therapeutic interest and to reduce the total amount of heat absorbed by the root and surrounding tissues . energy bands released from the fiber may be uniform in thickness , not uniform in thickness , or graduated depending on the clinical needs of energy release . the energy emissions from the working tip may also be partially or completely blocked at its most distal terminal extension to reduce or completely eliminate energy emanating from the tip . such capping may be of value when operating around delicate anatomical structures or to conserve , or redirect energy flow to its more proximal side - firing counterparts . in the second energy distribution embodiment , the controlled release of energy is accomplished along the entire three - dimensional working length of the fiber and all areas are fired simultaneously . total energy delivered is calculated and monitored from the laser source with appropriate safeguards for over and under - exposure . the laser tip 12 is designed to deliver sufficient energy to achieve the desired outcome but importantly , the energy must be controlled to prevent destroying delicate apical root canal anatomy which could complicate treatment or retreatment efforts , if necessary . the third energy distribution embodiment is the calibration markings of the sleeve that houses the laser tip or the calibration markings are placed directly onto the external aspects of the fiber cladding or reflective coating itself ( see fig1 and 4 ). such markings may be calibration markings , numbers and / or color - coded bands of clinical significance . such markings are sized to incorporate a direct energy release relationship to the disinfection / sterilization energy requirements for that zone depth . such markings may be used in conjunction with time measurements to coordinate the movement of the active tip after a predetermined amount of energy has been dispensed . endodontic applications will require that this sleeve 18 be bendable / flexible so the laser fiber and sleeve / sheath can be curved to more than a 90 degree angle . clinical access and usage requirements dictate that it is a requirement that the insertion of the disposable tip into the handpiece be able to be rotated 360 degrees at the junction 26 with the handpiece ( fig1 ). it is most likely that the features of the described first embodiment will be included with the third embodiment ( fig2 ) to create a tip that would fire in zones , such that the zones would overlap slightly upon removal of the tip , ultimately dosing the entire root canal system over the controlled withdrawal of the tip . variations in scoring methods for energy distribution embodiments are further illustrated in fig1 - 9 . it is envisioned multiples of the disclosed series of tips may be used in clinical practice . the first tip is an end - firing tip used to treat the apical region of the canal ( fig3 ). its configuration and energy release are such be such that it will not iatrogenically damage the delicate apical anatomy and yet produce emissions designed to penetrate the apical portion of the root to exert its effects on pathogenic micro - organisms residing on the outside surface of the root and in the surrounding tissues . in addition , there can be different styles of side - firing tips ( see fig2 , 4 , 5 and 6 ). another side - firing tip is “ end capped ” ( fig7 a ) in such a way that no emissions are produced at the tip as would be the case in an “ end - firing ” embodiment . the construction of this design allows for irradiating the canal without producing emissions directly out the apical end of the root . this embodiment is selected in cases where delicate anatomical structures ( neurovascular ) approximate the root end . in another embodiment ( fig2 ), the side - firing tip could have an apical end - firing component as well . while the circumferential openings in cladding 18 b , whether as illustrated in fig2 and 4 , provide useful diode laser delivery mechanisms , it is also within the scope of the present invention to utilize longitudinal , or axial slots 35 as is illustrated in fig1 . in this embodiment , the slots forming the openings for axial radiation may be as narrow as about 0 . 1 mm up to about 2 mm , and be spaced at regular intervals such as 180 °, 120 ° or 90 apart . particularly in these embodiments , the head 11 or upper end of the sheath 16 include an indexing marker , or the like to provide the operator with information as to the orientation of the laser , and particular the irradiating zones . prior to using the laser in this protocol , endodontic treatment can be completed by the method of the clinician &# 39 ; s choice as long as the protocols utilized fulfill the well - established mechanical and biological objectives required for predictable success . the procedural steps include complete access , followed by negotiating and shaping the canal to facilitate three - dimensional cleaning and obturation of the root canal system . the only unique requirements are threefold : 1 ) the primary canal must be completely negotiated to its terminal extent ; 2 ) the canal must be prepared into a uniform tapered shape of between 2 and 10 % such that each cross - sectional diameter narrows in an apical direction ; and 3 ) the terminal extent of the canal must be minimally enlarged to about 0 . 20 mm or about 200 microns . this is necessary so that the irradiating fiber tip can reach within about 1 mm of the terminal extent of the preparation . the taper prevents binding and breakage of the exposed fiber in smaller , curved canals . if there is proximity to vital anatomical structures such as the mental foramen or mandibular nerve , an end - capped tip should be selected . once a canal has been completely mechanically and chemically prepared , the preparation must be rinsed with edta to promote the removal of the smear layer . it should then be rinsed in a sodium hypochlorite solution to neutralize any residual edta solution in the canals . the sodium hypochlorite can then be rinsed with sterile saline , sterile water or dried out directly with paper points . in any scenario , excess solutions of any type should be removed with the use of paper points until the paper points are retrieved from the canals consistently dry . excess water will absorb the laser energy and reduce the available energy available to targeted cells . after these procedural steps have been accomplished , the disposable laser tip is selected and fit so its working end can be inserted to within about 1 mm of the terminal extent of the canal preparation . importantly , the most coronal extent of the laser &# 39 ; s working area must not protrude more than about 1 . 5 mm into the access cavity to provide protection and prevent lateral radiant laser energy from reaching the clinician , staff , and patient . at this point the procedure depends on which of the two energy phasing embodiments is selected ( such as fig1 ). in the first , and preferred embodiment , the laser tip releases energy at its tip and laterally simultaneously along the entire length of the working fiber , irradiating the entire canal without the need to move the active tip . in a second embodiment ( such as fig2 ), the active tip 24 may have zones or bands of laser irradiation and bands where no irradiation may occur . this may be done for purposes of controlling the location of the energy release , reducing the heat distribution to the tooth or to compensate for power levels inadequate to power the active tip effectively . if this embodiment is selected , then the tip will need to be moved , in a coronal direction , until all of the treatment zones have been lased . in either instance , energy release is controlled directly by the laser unit via an automatic shut off . in the instance of irradiating specific zones , then following the completion of laser treatment within any given zone , the energy is automatically shut off signaling the clinician to move to the next band or zone . to begin the protocol , starting at the root apex , disinfect / sterilize the canal by engaging the power source for the prescribed amount of time , depending upon the embodiment used and move the tip coronally so as not to recontaminate the previously lased area after its sterilization . a controlled amount of energy is deposited for a particular time at a particular location and distribution within the root canal system . the exact method would depend upon the embodiment selected . if energy application is to be phased , then the tip is to be stepped back coronally in a manner consistent with the use of the calibrations and color - coded markings along the sleeve / sheath or fiber . if the embodiment selected is one in which all of the energy is deposited at once along the entire working length of the fiber and the length of the fiber is long enough to cover the entire length of the canal , then there is no need to proceed in multiple phases . one variation may be the movement of the spiral embodiment once as previously described to treat the areas left untreated by the spiral design and allow the treated areas to cool . once inserted to the proper depth , the tip is activated for the appropriate amount of time to assure the disinfection of the canal contents along with the ablation / vaporization of the tissue fragments within the primary and secondary anatomy . once the calculated energy has been deposited , the tip is simply withdrawn and placed in the next primary canal to be treated . when there are multiple canals , this process is repeated for each canal within any given tooth . after the laser process has been completed for all primary canals , residual charring may be removed by flushing out the canals with solutions of edta and sodium hypochlorite . this irrigating process is enhanced by agitating the solution utilizing an instrument manually or via a mechanized way . the canals should then be reflushed with irrigant and dried . the use of a diode laser as an adjunct to the sterilization of the root canal system as described above results in the significant generation of heat in the treated root canal as a byproduct of the laser operation . the ability to keep the heat below biological thresholds that are safe to the surrounding structures , such as nerves , blood vessels , periodontal ligaments and bone is of paramount importance for the safe and effective operation of diode lasers . the more efficiently the delivered energy is used , the less waste heat will be generated . irrespective of which embodiment or technique is chosen , the operator may elect to further enhance both the disinfection and cleaning of the canal by subsequently filling the previously treated canal ( s ) with an aqueous solution and activate the tip again at a low wattage of between 0 . 5 to 2 watts for short periods of time followed by resting periods to take advantage of the photoacoustic effects of this device . another essential ingredient to the successful operation of the diode laser in intracanal endodontic applications , where direct visualization is not possible and work is done “ blind ”, is some form of system that assures that the full and calculated strength of the radiation is dispensed as prescribed . degradation of the dispensing tip will result in a reduced level of radiation dose and hence may not accomplish the desired result . assumption of disinfection when not accomplished is undesirable and may result in treatment failures . conversely , the turning up of the power to assure disinfection because the operator assumes degradation , but cannot quantify it , is similarly undesirable due to the increased and likely unnecessary extra heat generation and unwanted tissue destruction . additionally , it is essential to know when the laser tip has extended past the confines and safety of the root proper . activation of the laser under these conditions below the tooth root and into the gum / tissue area will result in the direct application of laser energy to the surrounding tissues possibly resulting in unintended damage to those tissues . the inventive embodiments particular to each category listed above are described under their respective headings below . because of the dramatic effect of the selected wavelength laser operation , and the more efficient in - canal heating targeted to the water contained therein , various tip configurations can enhance the power wave of energy generated by the inventive technique . there are four different inventions / embodiments designed to optimize the use of treatment energy . treatment energy optimization results in more effective treatment outcomes per unit dose of treatment energy applied . results related to energy optimization include reducing waste heat needing to be dissipated into the surrounding tissues thereby increasing safety to the surrounding tissues . the rationale , embodiments and methods proposed by this invention to accomplish that result are listed below . the fiber optic bundle used in endodontic treatment applications is encased in a outermost protective cladding or sheath , hereinafter , “ sheath ” or “ sheathing ”. in endodontic treatment applications the protective sheathing may remain intact or be otherwise scored in multiple configurations with the intention of allowing lateral emissions . such emission angles may vary from one degree to 90 degrees from the long axis of the fiber . the release of treatment energy within the relatively enclosed confines of a root canal system will impact the dentinal walls at different angles resulting in scattering , transmission , absorption and reflection of the treatment energy . the first embodiment is designed to re - reflect the scattered and reflected energies that reach the sheathing material back to the tooth structure as treatment energy . the concept of this embodiment is to coat the outer surface of the sheathing with any reflective coating that will re - reflect energy through multiple iterations until the energy has been ultimately absorbed by the tooth structure or otherwise lost through the coronal aspect of the access to the root canal system . such a coating is more particularly illustrated in fig1 . similar to the application of a reflective coating to the exterior sheathing of the fiber optic bundle as previously described , a variation , and new useful embodiment by the removal of the fiber optic sheathing exposing the optically reflective layer below . the original purpose of the optically reflective coating is to reflect light energy back along the length of the fiber that energy not in the long axis of the fiber which would otherwise be lost in the absence of the optically reflective coating . this is done by using a material in the reflective coating that has a lower index of refraction than does the transmitting core . in this embodiment , some or all of the outermost protective sheathing is removed exposing the external aspect of the optically reflective coating underneath . when exposed to the scattered and reflected treatment energy , the exposed reflective layer below will re - reflect those energies back to the tooth structure as treatment energies . while the reflectivity is not normally as high as an additional reflective coating applied to the outermost sheathing , it can be significant , and its costs sufficiently lower to warrant manufacture . this exposure of the underlying reflective coating will have the same result as the application of the reflective coating on the exterior surface of the sheathing , i . e . the re - reflection back to the tooth structure of non - absorbed energy and its concomitant results as previously described . this embodiment may be used in combination with the application of a reflective coating applied to the external aspect of the sheathing as described above in that some of the fiber may have the sheathing removed to expose the underlying reflective surface while other areas of the same fiber may be coated with a reflective substance on the external sheathing itself . the combination of both approaches may result in an enhanced treatment result . the two embodiments , one showing the sheathing removal only ( fig1 ) and one showing the combination of sheath removal and sheath reflective coating ( fig1 ) are shown . irrespective of whether a reflective coating is exposed or applied to the surface of the external sheathing as previously described , there exists another significant portal of exit for applied treatment energy . that portal is through the occlusal or coronal access to the root canal system , i . e ., the entry column of the treating fiber . in principle , it is similar to the insertion of a water hose into a piece of pvc pipe capped on only one end . the water pressure will clean the side walls of the internal aspect of the pipe to a certain extent , but the uncapped and unsealed nature of the pipe at the hose &# 39 ; s entrance allows water to exit the pipe reducing the water pressure and its effectiveness inside the pipe itself . in this embodiment a flexible stop , similar to an endodontic stop as used on endodontic files , and is preferably coated with a reflective material on the side facing the canal opening . its purpose is to stop the egress of wasted energy in the coronal direction and re - reflect it back into the root canal system as treatment energy . in such an embodiment , the stop will have an appropriate sized hole pre - made through which the treatment fiber 18 a is inserted . the combination treatment fiber / reflective stop is then be inserted into the tooth . once the fiber reaches the prescribed treatment depth , the reflective stop or shield is be slid down the fiber so as to seal either the chamber access or preferably , the entrance to the canal orifice itself . once so sealed , the treatment energy is dispensed and the reflective stop acts to re - reflect escaping energy back to the treatment zone with the attendant benefits of increased treatment efficacy and waste heat reduction . examples of this embodiment are illustrated in fig1 , 15 a and 17 . uv light is well known to be an effective sterilizing agent . its application in the sterilization of root canal systems has only recently been explored . while it can be effective in the disinfection of root canal systems , when conventionally applied , it lacks the power to ablate tissue , or penetrate far into the dentinal tubules . because of this its effects on bacteria embedded in the tubules are uncertain and variable . despite its efficacy in disinfection , tissue remnants , necrotic and vital , remain intact serving as a future foodstuffs for future bacterial / fungal infections . the combination of laser energy and uv light in the disinfection of root canal systems has not been commercially explored to date . in the scenario of an effective treatment program , the addition of uv light energy to the root canal system , either before or after the application of laser energy , may result in the ability to use reduced laser energy resulting in less heat to be dissipated by the surrounding tissues resulting again in both greater efficacy and greater safety . an alternative embodiment incorporates a dual - type emission source in which one source supplies the uv light and run the uv emissions down the treatment fiber then , permitting a switch to the laser emission source and run the laser emissions down the same , or different , fibers . such a dual source approach offers cost and space efficiencies while allowing for a choice of treatment modalities . the operator may elect to operate only the uv emissions in areas of delicate anatomy or where the containment of the laser energy cannot be assured . examples of such areas may include proximate anatomic structures such as the mandibular canal , mental foramen , infraorbital nerve . treatment of root canal systems is done “ blind ” for four primary reasons : 1 ) the canal space is small and cannot be visualized during treatment . 2 ) there are many ramifications / accessory canals that extend obliquely from the long axis of the primary canal . the contents of such ramifications / accessory canals cannot be therefore visualized directly . 3 ) the goal of endodontic treatment is to ablate residual tissue fragments and disinfect / sterilize the primary canals , secondary canals and dentinal tubules . the limits of human vision , and even its augmentation with surgical operating microscopes , do not allow such a level of resolution so as to distinguish individual bacteria , much less their status as living or dead . 4 ) the insertion of the treatment fiber and the operator &# 39 ; s fingers block direct vision at the time of treatment . therefore , it is imperative that the treatment tip deliver the amount of treatment energy calculated to be effective in the cleansing / disinfection of the root canal system . it is therefore desirable that a single use application treatment tip be configured so that a consistent , known level of treatment energy can be predictably and reproducibly applied to the root canal system . with repeated use the laser treatment tips suffer breakage of the fiber optic core transmission fibers due to the repeated flexion generated by use in tight and curved root canal systems . such breakage of fibers disrupts the light throughput reducing the delivered dose of energy and rendering disinfection / sterilization results uncertain . the tips are additionally subject to charring after use — also serving to reduce output during later use . any indicator , safety , or reflective coatings will be similarly be rendered inactive or unreliable by previous use . for these reasons , it is strongly recommended that the treatment tip should be disposable / single use . similarly , current sterilization concerns require such tips should be for single use only . certain nations have mandated that endodontic files shall be single use only because of the inability of routine sterilization processes in use today to kill prions . in this embodiment , the tip may also be coated in an indicator that changes color after use or a predetermined amount of use . for example , the disposable tips may be coated green in color as they come from the manufacturer , but turn red after activation with heat , laser or uv energy . such an indicator should make it easy for the operator and auxiliary staff to distinguish between used and unused tips . in addition to the use of uv light in areas of delicate anatomy , one needs to include provisions for the safe operation of the laser in the advent that such a uv add - on capability is not available in the treating unit . the calculation of the exact length of the root is more art than science . hence , it is very easy for the operator to inadvertently extend the treatment laser fiber past the protective confines of the tooth structure itself . in tooth length determination statistical norms are not adequate in that they are the average of a large population and bear little relevance to the unique , individual , tooth being treated . failure to compensate for the individual peculiarities at hand can be catastrophic . angulation of x - rays may produce an image that is longer or shorter than the actual tooth length . additionally , the end of the root canal confines do not coincide with the radiographic end of the root the majority of times . electronic apex locators also have mechanical and interpretive error rates that are far from rare and can be fairly significant in degree . tactile sense alone cannot be relied on due to curves , constrictures , and blockages in the root canal system . measurement by paper points cannot be relied on exclusively either as there can be bleeding into the canal resulting in a short reading . another problem with this method of measurement can be the existence of dead space or tissue which is not moist or does not bleed exterior to the confines of the root structure . in practice , the operator will usually rely on more than one modality to make a clinical judgment about the actual tooth length . such judgments may , or may not , be accurate . one embodiment used to aid in this process coats the terminal apical end portion of the fiber with a coating that is either water soluble , changes color after exposure to moisture or blood , or uses the precipitation of a char layer after an initial low energy activation to indicate whether or not the proposed laser tip activation zone resides safely within the confines of the root structure . such change may be induced by dissolving of the primary coating , exposing a different colored undercoating , a chemical reaction induced by the presence of blood or moisture , or the precipitation of a char on the exposed tip surface . under this embodiment , it is envisioned that such color change / indication shall be rapid enough and visible enough to allow the operator to determine when he / she has exited the confines of the root canal system and is the more vulnerable tissues surrounding the root . although the present invention has been described in terms of specific embodiments , it is anticipated that alterations and modifications thereof will no doubt become apparent to those skilled in the art . it is therefore intended that the following claims be interpreted as covering all alterations and modifications that fall within the true spirit and scope of the invention . academy of laser dentistry . diode and nd : yag lasers clinical case studies . wavelengths 2004 ; 12 : 1 . [ 2 ] bornstein e . near - infrared dental diode lasers : scientific and photobiologic principles and applications . dent today . mar 2004 ; 23 : 102 - 108 . [ 3 ] grant s a , soufiane a , shirk g , et . al . degradation - induced transmission losses in silica optical fibers . lasers surg med . 1997 ; 21 : 65 - 71 . [ 4 ] kuhn t s . black - body theory and the quantum discontinuity , 1984 - 1912 . chicago , ill . : university of chicago , press : 1978 : 1 [ 5 ] manni j g . dental applications of advanced lasers . burlington , mass : jgm associates , inc ; 2000 : section 1 . [ 6 ] harris d . dosimetry for laser sulcular debridement . lasers surg med . 2003 ; 33 : 217 - 218 . [ 7 ] gregg r h 2na , mccarthy d . laser periodontal therapy : case reports . dent today 2001 ; 20 : 74 - 81 . 8 gutknecht , n , schippers r f m , lampert f , bactericidal effect of a 980 nm diode laser in the root canal wall dentin of bovine teeth .