referring now to the discussion that follows and also to the drawings , illustrative approaches are shown in detail . although the drawings represent some possible approaches , the drawings are not necessarily to scale and certain features may be exaggerated , removed , or partially sectioned to better illustrate and explain the present disclosure . further , the descriptions set forth herein are not intended to be exhaustive or otherwise limit or restrict the claims to the precise forms and configurations shown in the drawings and disclosed in the following detailed description . fig1 a and 1b illustrate patient specific digital or physical dental anatomical diagnostic models 100 and 101 that expose the partial upper jawbone bone structures 103 and a lower jawbone 104 at the surgical sites and the areas of interest . in areas where the bone structures are not exposed , the model has gum tissue surface structures 102 . as in fig1 a and 1b , these gum tissue surface structures 102 usually appear towards the distal end of the posterior regions and the palatal area of the upper jaws . fig1 c and 1d depict a digital image of a lower jawbone 104 and a digital image of the gum tissue surface structures 102 positioned relative to one another , from which diagnostic anatomical models like 1 a and 1 b are created . the bone structure data can be obtained by tomography imaging devices such as ct and cb ct , and may be exported as a file format , such as stl , suitable for reverse engineering and 3d imaging . then the data file can be accurately aligned with the surface scan data of the gum tissue 102 obtained by devices such as laser and optical scanners by means of matching fiducial markers on the imaging apparatus that the patient wears during the tomography scan to the markers &# 39 ; positional information on the surface scan data . if the bottom of the apparatus represents the patient &# 39 ; s gum tissue surface , the image of the patient &# 39 ; s gum surface can also be obtained by scanning the imaging apparatus alone using a tomography device . in this case , these two ct data files can be aligned by the fiducial marker location ( s ) after each structure is thresholded and is exported as a proper file format for modeling . if a radio opaque duplicated denture is used as an imaging apparatus , the bone structure data and the gum surface data can be obtained with a single ct scan of the patient with the imaging apparatus in place . after the necessary structures are properly aligned in a file format suitable for 3d modeling , the data files can be combined and used to design a digital anatomical diagnostic model with a partially exposed bone structure in the area of the surgical site . the osteotomies of simulated dental implant placements 105 may be created either digitally on the digital anatomical diagnostic model or manually on the rapid - prototyped physical anatomical diagnostic model . then a drill guide apparatus may be designed on this type of digital anatomical diagnostic model so that it will accommodate drill guide bushings or holes which guide the surgical drill according to the planned osteotomies either on the digital anatomical diagnostic model or the physical anatomical diagnostic model . alternatively , the whole apparatus can be designed manually on this type of physical anatomical diagnostic model with dental materials such as , but not limited to , light cured composite , cold cured resin or acrylic , or thermoplastic . fig2 a - e are exemplary designs of a base frame 200 for an upper jaw ( fig2 a - 2c ) and a lower jaw ( fig2 d & amp ; 2e ). the base frame 200 may be made of a transparent or semi - transparent resin or other composite material that gives the surgeon maximum visibility of the surgical site , but it may also be made of a colored resin and other composite material or metal that provides the base frame 200 with enough rigidity for stability and the right amount of flexibility in clasping areas . in order to obtain rigidity and flexibility in different areas , the frame 200 may be designed to have thick areas and thin areas accordingly within the frame . overall however , the base frame can be more flexible than one piece surgical guide since the surgical drill guide section placed on top of it can solidify the whole drill guide assembly and the flexibility allows the device to clasp on to the undercut easily . the base frame 200 is shown positioned on top of the upper jawbone structure 103 . a plurality of osteotomies of simulated dental implant placements 105 are shown about the periphery of the upper jawbone structure 103 . a handle 203 is secured towards a forward portion of the base frame 200 which is used to aid in the maneuverability of the base frame 200 . interlocking connectors 204 are firmly mounted to , or formed part thereof , the base frame 200 , and provide guides for the surgical drill guide housing frame 300 to connect thereto . the arrows 20 depict potential pressure impinging points for the drill guide housing frame 300 to impinge upon . fig2 d shows a base frame 200 on the type of anatomical models explained above , and gum tissue contact portions 201 are placed on the gum tissue areas of the model . although this portion may have broad area contacts with the gum tissue 102 , it may also have strategically placed smaller spot contact areas 205 as shown in fig2 c . in some designs , certain areas of gum tissue contact portion can be used to place temporary anchors through the gum tissue into the patient jawbone by small screws , pins or other fastening devices . the surgical device 200 may also have one or more clasping lateral contacts 202 ( see fig2 b - 2e ) that may simply contact the lateral wall of the exposed jawbone 103 and 104 or engage its undercut . as shown in one exemplary design of the base plate 200 for a lower jaw 104 ( fig2 d & amp ; 2e ), clasping lateral contacts 202 may be connected to the gum tissue contact portion 201 by stabilizing / clasping arms 207 that may or may not have contact with the oral structure . the stabilizing / clasping arms 207 extend out from a base frame 200 and / or drill guide housing frame 300 which may be turn into a drill guide housing section 400 with drill guide bushings . when the frame is placed on the oral structure or anatomical diagnostic model , the stabilizing / clasping arms 207 slightly flex out and then clasp securely onto the oral structure 104 . although the stabilizing / clasping arms 207 are illustrated as peninsulas that extend out of the tissue contact area , the stabilizing / clasping arms 207 may be continuously connected to the tissue area like in the exemplary base frame 200 shown in fig2 f . clasping lateral contact area 202 may also be used for placing a temporary anchor directly into the jawbone 104 if the patient &# 39 ; s oral structure does not allow the device to have enough retention . similar to the clasping lateral contacts 202 , one or more occlusal / lateral stabilizing rests 206 ( fig2 d ) may be strategically placed to contact the jawbone 104 to work along with the gum tissue contact portion 201 and the clasping lateral contact 202 in order for the device 202 to be securely positioned inside of the patient &# 39 ; s oral structure ( see fig1 ). this section may also be connected to the gum tissue contact portion 201 by at least one stabilizing / clasping arm 207 . the arrows on fig2 a , 2 e and 6 c indicate the direction of force 20 applied from each contact point to the oral structure , and show how stabilizing / clasping arms 207 help fixate the device 200 in place . although it is not illustrated , due to a particular shape of the jawbone 103 , 104 , the base frame 200 may be designed to have only tissue contacts without any jawbone contact and to have a separate detachably attachable part that snaps onto it and engage the jawbone . alternatively , this bone clasping part can be a latch connected to the base frame 200 by a hinge . the base frame 200 may also include a handle 203 on fig2 a - 2c that may be used when removing the device from the oral structure , and an interlocking connector 204 ( fig2 a , 2 b , 2 d , 2 e ) that securely connects the base frame 200 to a surgical drill guide housing frame 300 ( fig3 a - 3e , and fig4 a , & amp ; 4 c ). the handle 203 may also be a handle / connector , a part of which works as a male interlocking connector . fig2 f illustrates the base frame 200 having connectors 204 that are secured to the upper service thereof . stabilizing arms 207 are positioned around its outer periphery with openings 208 being positioned adjacent thereto . fig3 a illustrates an exemplary drill guide housing frame 300 configured to be disposed on the base frame 200 , which collectively form an assembly 310 . material requirements for the drill guide housing frame 300 are same as the specifications for the base frame 200 . the drill guide housing frame 300 may securely snap onto the base frame 200 by the interlocking connectors 204 ( fig2 a , 2 c , 2 d , 2 e ) and the connector receptors 304 ( fig3 b ), also by the handle 203 and handle / connector receptors 303 ( fig3 a - 3d ), along with various stabilizing rests and / or clasping contact areas between the two devices 200 , 300 . as illustrated , the interlocking connectors 204 on the base frame 200 may be male connectors with strategically placed slight undercuts , and the connector receptors 302 and 303 on the drill guide housing frame 300 may be female connectors . however , various types of different connector mechanisms can be used for this purpose . similar to the handle / connector 203 on the base frame 200 , the handle / connector receptor 303 may be used when removing the device from the base frame 200 , and it may also be used as a receptor for the handle / connector 203 . similar to the contact points / areas of the base frame to the oral structure , the drill guide housing frame 300 may have clasping or resting contact points / areas to the base frame 200 besides the connectors . these contact points / areas may be strategically placed to work together along with the connectors not only to ensure a secure fit of the part to the base frame 200 but also to lock in the entire device ( the base frame and the drill guide housing section ) onto the oral structure by adding an extra layer of thickness and applying more clasping force . the base frame 200 and the surgical drill guide housing 300 may be designed to work together to make the assembly 310 set snugly fit onto the oral structure 100 and yet have great rigidity so that it is very stable in the patient &# 39 ; s mouth as well as on the physical anatomical diagnostic model . although not illustrated , the frames may be fastened together using any other suitable fasteners including , but not limited to , screws , pins and latches . the holes 304 on the connector receptors 302 and handle / connector receptor 303 shown on fig3 b and 3d are liquid escape holes 304 that allow excess moisture and debris to escape so that they will not be trapped in - between the devices 200 and 300 . it should be noted that the liquid escape holes 304 can be created in different areas of the drill guide housing frame 300 . the larger opening holes 305 in the middle of the devices 300 and 401 in fig4 a and 4c are clearance openings for fastening anchor devises such as screws and pins that are used to fasten the base frame 200 onto the jawbones 103 and 104 without engaging with the drill guide housing frame 300 . however , the larger opening holes 305 may also be used as liquid escape holes 304 . unlike the handles 203 and 303 , other exemplary handles may not have a connecting function . the handles may be on either one or both of the base frame 200 and the drill guide housing frame 300 , and there may be more than one handle 203 and 303 on both frames . moreover , the handles on the base frame 200 and the drill guide housing frame 300 can work together as a combination handle unit . ideally , the combination handle unit is designed to leave a small space at least in a certain area between the devices &# 39 ; handles so that a hand instrument or other types of tools can be inserted into the space to pry the frames apart . also , similar spaces 601 for the instrument may be created between the frames in other areas to make the separation of the frame easier . see fig6 d , 8 and 11 . optionally , the device may also feature skirted areas 301 ( fig3 b ) over the intended surgical site ( s ). this feature may be useful when the surgeon plans the osteotomies 105 on a physical anatomical model and the device is rapid prototyped or cnc milled from the design created on the digital anatomical model . the skirted areas may be a thin shell that extends from the device 300 and covers the intended surgical site ( s ). the purpose of this feature is to provide base structure for the surgical drill guide site ( s ). when the osteotomies are planned on a rapid - prototyped or milled physical anatomical model , the implant positions and angulations are unknown at the time of manufacturing of the surgical drill guide frame or frame set . by having a thin skirted area 301 over the intended implant site as a base structure , it may be easier to prepare the surgical drill guide site ( s ) on the device 300 . also , the skirted area 301 can be made so that the top surface or the bottom surface of the section represents the patient &# 39 ; s gum tissue 102 . it can also be made so that the bottom surface of the section sits on top of the bone , a certain distance away from the bone below or above the gum tissue . by going through the procedure that is shown on fig3 c , the holes 306 that correspond with the planned osteotomies 308 will be created on the skirt as shown on fig3 d . drill 306 is used to create the holes 306 . when the surgical drill guide sites are prepared on the physical anatomical model 100 , positioning pins 308 may be used to set the angulations of the osteotomies and to position the surgical drill guide parts 309 as shown in fig3 e . fig4 a illustrates an exemplary surgical drill guide section 400 that was trimmed after surgical drill guide sites are prepared so that the device 400 may provide improved surgical site visibility and good facility for irrigation . optionally , metal or ceramic tube type 309 a or open - face type 309 b surgical drill guide bushings can be attached to the device 400 , but the device may not have any added parts to the drill guide site . if the implant placement is digitally planned on the digital anatomical model prior to the model manufacturing , the drill guide housing frame 300 can be digitally designed like this illustration , without any skirted area 301 , so that the drill guide bushings 309 a and 309 b can be attached to the device 400 right after manufacturing . another exemplary surgical drill guide section 400 shown in fig4 d for a lower jawbone 101 snapped on to the base frame 200 illustrates the space 105 between jawbone surface 103 and the bottom of the drill guide housing frame 400 over the surgical site , which may be preferred by surgeons for the better irrigation . however , as previously described , the bottom surface of the drill guide housing frame may be set at a different height . fig5 illustrates the modified duplicated denture appliance 500 attached to the base frame 200 . one way of creating this appliance is to scan the patient &# 39 ; s denture or duplicated denture surfaces , align the data to the anatomical model , and modify it to fit on the base frame 200 . this appliance 500 may have features such as connector receptors 302 , irrigation holes 304 , and openings for fastening anchor devices 304 just like a surgical drill guide housing frame 300 . this appliance 500 may be used to verify the position of the base frame or the single piece surgical guide with patient &# 39 ; s bite . other examples of attachments include , but are not limited to , an implant pick up impression tray , an implant transfer jig tray , and a bone adjustment jig . advantages of the drill guide assembly 310 having the base frame 200 and the drill guide housing frame 300 may include : 1 ) interchangeable multiple guide frames 300 can be used during the surgery while the base frame 200 can be securely positioned in the patient oral structure ; 2 ) if , for any reason , the doctor changes the positioning of one or more of the implants from the original plan , and cannot use the surgical drill guide for those particular site ( s ), or needs to work on the bone , he / she can temporarily remove the drill guide housing frame 300 from the base frame 200 without disturbing the position of the base frame 200 ; 3 ) various types of additional attachments can be placed on the base plate 200 without the drill guide parts covering the surgical sites . the drill guide assembly 310 is especially beneficial when the base frame needs to be temporarily anchored to the patient &# 39 ; s jawbone . more than one surgical drill guide section 400 may be needed in order to accommodate a surgery &# 39 ; s specific needs . as illustrated with the positioning pins 308 a and 308 b in fig4 b , two of the intended osteotomies 105 a and 105 b are very close to each other and have intersecting positioning angulations . in this case , a second surgical drill guide section , 401 in fig4 c may be created for one of the planned osteotomies 105 a . this type of additional surgical guide section 401 is detachably attachable to the base frame 200 and is interchangeable with the first surgical drill guide section 400 . alternatively , smaller parts that house the surgical drill guide bushings 309 or drill guide holes for specific implant placement sites may be attached to the first surgical drill guide section 400 . although it is not illustrated , another benefit for having additional surgical drill guide section 401 is to accommodate larger size surgical drill guide bushings , 309 a and 309 b that are subsequently used for finish drilling osteotomies 105 . fig6 a - 6d represent a situation in which the doctor decides to reduce the jawbone prior to implant placement . fig6 a is an anatomical diagnostic model of a lower jaw 101 which shows a gum tissue portion 102 and a partially exposed bone structure 104 . the doctor may wish to modify the bone 104 b prior to the implant placement as in fig6 b . in this case , the base frame 200 ( fig6 c ) may be designed according to the doctor &# 39 ; s specification either on the digital model or the physical anatomical diagnostic model so that it can be used as a bone reduction jig . fig6 c illustrates a base frame ( 200 ) on an anatomical diagnostic model with a modified lower jawbone 104 . a drill guide section 400 fig6 d may be designed on top of the base frame 200 to be used for implant placement . various types of additional detachably attachable appliances can be added to the surgical drill guide 400 . one example of an additional appliance is a modified duplicated denture attachment 500 . it will be appreciated that the surgical drill guide can be manufactured as single piece 700 ( fig7 ) that contacts both gum tissue and exposed bone . single piece apparatus 700 has combined functions of both base frame 200 and the surgical drill guide section 300 . the device may have all or some of the features described above , or it may include different types of attachments . lateral contacts 202 on the forward edge are connected to an arm 207 , which may be a part of the single piece guide 700 . fig8 is an exploded view of a two part surgical drill guide assembly 401 that is shown in fig6 d . the assembly consists of the surgical drill guide section 400 and the interlocking base 200 . collectively , the drill guide section 400 and base 200 can be snapped together and strategically placed relative to the lower jaw 101 which , in this instance , is a physical diagnostic anatomical model of a lower jaw for a human being . the base 200 has a base member 203 at a rearward portion , a first outwardly extending clasping or stabilizing arm 207 , and a second arm 206 that extends from the base member 203 . the arms have flattened portions and are resilient for placing a force on a jaw . the base 200 is operable to be received on the lower jaw 101 and located relative to the interior 250 and exterior 252 surfaces of the lower jaw 101 . in particular , the base 200 further has lateral contacts 202 at internal locations , which are strategically located to impinge upon exterior surface 252 of the lower jaw 101 . for example , lateral contact 202 a is operable to impinge upon exterior contact 252 a . likewise , lateral contact 202 b is designed to strategically impinge upon contact surface 252 b in two locations relative to the exterior surface 252 of the lower jaw 101 . likewise , lateral contact 202 c is located on an outwardly extending portion of the base frame 200 , and is operable to engage interior surface 250 c of the lower jaw 101 . these contact points , and others , are designed to impinge forces 20 ( see fig2 a , 2 e and 6 c ) for aiding and positioning , the base frame 200 relative to the lower jaw 101 . once the base frame 200 has been positioned relative to the lower jaw 101 , the surgical drill guide section of 400 has receptacles that are snapped to interlocking connectors 204 that , in the exemplary model , are positioned at three locations about the base frame 200 . it will be appreciated that more , or fewer , interlocking connectors 204 can be provided . the locking fit between the interlocking connectors 204 and the corresponding female receptacles that are on the underneath side of the surgical drill guide section 400 , create a snap - fit type connection . this snap - fit configuration provides for ease of separability of the drill guide section 400 and the base frame 200 , as well as provides a self - centering locating arrangement for making sure the assembly 401 is properly fit together . the drill guide section 400 includes a flattened center potion 303 that has a plurality of bushings 309 a or 309 b extending through the flattened portion . the drill guide section 400 further may have water escape holes 304 , along with the open face drill guide bushings 309 b , as well as a separation feature or openings 601 at three locations , which aid in separating the drill guide section 400 and the base frame 200 . the openings 601 are sufficient to allow a device , for example a dental instrument , to be inserted between the drill guide section 400 and the base frame 200 , so as to allow ease of separation of the two components . the open face drill guide bushings 309 b provide a guide mechanism for receiving positioning pins 308 . the bushings are preferably made of metal and they are anchored in the guide section 400 . the positioning pins 308 may be made of metal or hard plastic and are placed into the planned osteotomies within the lower jaw anatomical diagnostic model 101 and are configured to receive the bushings 309 b , which helps align the drill guide 400 relative to the jaw 101 . at the surgery , drill guide bushings guide the drills to create osteotomies for implant placement . fig9 illustrates another exemplary drill guide assembly 401 including a drill guide section 400 and a base frame 204 b , which also works as a bone reduction jig . the assembly 401 can be positioned relative to exposed bone area 104 b of a lower jaw 101 , which , in this visual , is a diagnostic anatomical lower jaw model . this particular lower jaw model 101 includes extracted teeth sockets 110 , which can be either recently extracted teeth or digitally simulated planned teeth extraction , a gum tissue area 102 , and nerve endings 112 . the base frame 200 b has interlocking connectors 204 formed on the upper surface of the base frame 200 b that can be integrally molded to the base frame 200 b . lateral contacts 202 a and 202 b are positioned about an interior surface of the clasping arm 207 and form pressure points for impinging upon exterior surface 252 of the lower jaw 101 at points 252 a , and 252 c , respectively . the surgical drill guide section 400 is shown ready to be positioned and connected to the base frame 200 b . drill guide bushings 309 a are provided within holes for receiving positioning pins 308 . an opening 601 is provided to help in separating the drill guide section 400 from the base frame 200 b . fig1 illustrates the fig9 surgical drill guide assembly 401 in an assembled condition . the drill guide 400 is shown in place relative to the base frame 200 b which in turn , is positioned relative to the lower jaw 101 . fig1 illustrates a bottom perspective view of the fig6 surgical drill guide assembly 401 . from this perspective , the underside of the base frame 200 and the drill guide section 400 can be more readily observed . the lower jaw 101 is shown with gum tissue 102 . the base frame 200 has scalloped or saddle shaped tissue contact portions 220 that are received by the gum tissue areas 102 of the lower jaw 101 . the clasping arm 207 has impinging areas 202 a and 202 b that impinge upon surfaces 252 a and 252 b , respectively , of the jaw 101 . likewise , impinging surface 202 c impinges upon corresponding internal surface 250 c of the jaw 101 so as to provide an inwardly impinging force 20 as previously depicted in fig6 c . the surgical drill guide section 400 has receptacles on the underside surface 452 that are operable to lockingly engage with interlocking connectors 204 ( fig9 ) of the base frame 200 . openings 601 provide a gap between the surgical drill guide 400 and the base frame 200 so as to allow for ease of separation between these two components . the recess 450 is slightly larger in physical configuration than the interlocking connector 204 . the interlocking connector 204 is sufficiently resilient , as is the receptacle 450 , so as to provide a positive snap - fit locking configuration between the components 400 and 200 . once together , an interlocked assembly 401 is created , which can be easily aligned relative to the jaw 101 . fig1 illustrates a perspective view of the base frame 200 , which is functioning here as a bone reduction jig , being positioned relative to the lower jaw 101 in the context of a mouth 150 . it depicts the lower jawbone having a shaved section 152 according to the clasping arm portion of the base frame 200 . extracted teeth sockets 154 are present and depict the location of the extracted teeth . an interlocking connector 204 is shown and is operable and ready to receive the surgical drill guide section 400 ( not shown ). fig1 and fig1 show different manufacturing methods of using an edentulous surgical drill guide or assembly 401 . fig1 illustrates a model based implant placement planning method 800 and fig9 illustrates a digital implant placement planning method 900 . both methods start with a digital anatomical diagnostic model , with partially exposed jawbone 101 in the area of interest , in a file format such as stl that allows reverse engineering and 3d modeling 801 and 901 . the digital anatomical diagnostic model 801 can be obtained by accurately aligning the surface scan data of the patient &# 39 ; s mouth or dental cast and the tomography scan data that is volume rendered and converted to a compatible file format . since all the devices are patient specific , the design and features of the apparatus is planned according to the patient &# 39 ; s oral structure , bone condition , and the surgical needs . although the apparatus can be created as one single surgical guide as described in the diagram in fig7 , the same or similar procedure may be applied when using a multiple piece guide . in both methods , a technician digitally designs the base frame 200 , and the drill guide housing frame 300 , along with additional frames and attachments , if any , using reverse engineering software program such as geomagic , radidform , and 3 matics , optionally combined with 3d modeling software such as rhinoceros 3d and solidworks ( see steps 802 , 902 , 803 and 903 ). the base frame 200 ( fig2 ) can be designed first on the digital model with partially exposed bone just in the area of the surgical site 802 and 903 and then the drill guide housing frame section 300 ( fig3 ) can be designed on both the digital anatomical diagnostic model and the base frame ( 802 and 902 ). by doing so , the surgical guide can be designed to obtain better fit and stability , because 1 ) it avoids bone contact in the areas where the density of the bone is too close to that of the soft tissue for its contour to be accurately defined in the ct images when the bone is porous , and 2 ) it also clasps onto rigid bone areas instead of contacting the malleable tissue surface alone . subsequently , if additional frames or attachments are needed , they can be designed to fit on the base frame 200 and / or the surgical drill guide housing frame 300 according to the part &# 39 ; s function 803 and 903 . some of the features and functions of the apparatus are the same or similar for the model based implant placement planning or the digital implant placement planning . however , several differences may be found in features and methods between for these two situations . fig1 illustrates a workflow 800 of a model based surgical planning . when the implant placement is planned on an aligned physical anatomical diagnostic model 812 created by rapid prototyping 811 the digital model 801 , the technician needs to design the drill guide housing frame or housing frame section 300 on the digital anatomical diagnostic model without knowing the exact plan of implants &# 39 ; positioning . naturally , the device is designed as a base structure of the surgical guide that will be assembled manually on the physical anatomical model . thus , the device often has the skirted area 301 ( fig3 b ) that extends over the intended site so that it is easier for the clinician or technician to assemble the surgical drill guide later on a physical anatomical diagnostic model ( see steps 806 - 809 ). similarly , other special parts that work on the physical model may also be designed to aid the surgical guide assembly . meanwhile , a physical anatomical diagnostic model is manufactured by rapid prototyping or cnc milling ( see steps 811 - 812 ), and ideal osteotomies are simulated on the physical anatomical diagnostic model by a qualified clinician ( step 813 ). alternatively , the modified anatomical diagnostic model with positioning pins placed into the osteotomies can be digitized by surface scanning ( step 814 ), and the drill guide 200 , 400 or 700 may be designed on the modified digital anatomical diagnostic model . if bone reduction is planned on a physical anatomical diagnostic model then the doctor can drill the ideal osteotomies into the physical model , ( see step 813 b ). after all the parts are designed on the digital diagnostic model , they are manufactured by rapid prototyping such as 3d printing and stereolithography or cnc milling 804 , cleaned , inspected , and verified on the physical anatomical model 805 . place the base frame and the drill guide housing frame 200 on the physical anatomical model 100 , as shown in step 806 . if the drill guide housing frame has skirted areas 301 ( fig3 b ) over the surgical site , drill holes may be placed through the skirted areas 301 with a hand piece 306 ( fig3 c ) so that the holes correspond with the planned osteotomies . since the drill guide housing frame is usually made with a transparent or semi - transparent material , the simulated osteotomies on the model is visible thorough the thin skirted areas 301 , and corresponding holes can be made . positioning pins 308 may be inserted into the osteotomies on the anatomical model through the holes of the skirted areas 808 . drill guide bushings 309 may be placed with respect to the positioning pins 308 and the bushings &# 39 ; distance may be set from the oral structure according to the preference . as briefly described above , the top or the bottom of the skirted areas 301 may be set at , below or above the gum tissue surface 102 . alternatively , the bottom of the skirted areas 301 may be made to contact the exposed bone . if the diameter of holes on the skirt is close to the inner diameter of the drill guide bushing , the bushing can rest on the skirted areas . the holes of the skirted areas 301 may also be made larger so that extra parts to control the height can be inserted onto the positioning pins 305 . it should also be noted that the drill guide housing frame 300 may be configured to accommodate various types of interchangeable drill guide bushings as well as most of depth control surgical guide system parts sold by various implant companies . after the positions are set , the bushings maybe attached to the drill guide housing frame with light cured composite or other adhesive materials 809 . additional light cured composite may be added to the frame to increase the rigidity of the device . light cured composite may be added around the positioning pins on the skirted areas 301 instead of bushings to conform drill guide holes or slots . when finished , the positioning pins may be removed from the physical anatomical model 810 . the skirted area can be then trimmed by a hand piece as previously described . additional drill guide frames , if any , can be made by repeating the process . with a model based implant placement system , it may also be possible to manually create a surgical drill guide that clasps the gum tissue and the jawbone with similar features without any digitally designed frame structures . it should be noted that the skirted area may not be necessary if the anatomical diagnostic model is surface scanned after the doctor drills the osteotomies , and the apparatus is designed on the modified digital model . fig1 illustrates a flowchart of digital surgical planning . when the implant placement is planned digitally on an aligned digital anatomical diagnostic model 902 as illustrated in fig1 , the creation of physical anatomical diagnostic model may be optional . in this case , the technician can design the drill guide housing frame according to the simulated osteotomies on the digital anatomical model . thus , there may be no need to create any skirted area . the support structure and receptor sites for the drill guide bushings can be digitally designed 903 so that the device is ready to receive the parts after prototyping . if any drill guide bushing parts with depth control function are going to be used , the device can be designed to receive those parts at the exact locations to accommodate the function . if the jaw bone 101 is reduced on the digital anatomical diagnostic model , the base frame 200 may be designed to function as a bone reduction jig . similar to the method for a model based implant placement system , the drill guide housing frame 300 is manufactured , along with the base frame and other additional frames and accessories , by rapid prototyping or cnc milling 905 . after cleaning and inspection 906 , the preferred drill guide bushings 309 can be placed into the drill guide frame 300 and secured by light cured composite or other adhesive material . for some type of drill guide bushings ( 309 ) adhesives may not be needed . the drill guide may also be created with built - in drill guide holes or slots without any separate parts if the device is made of an appropriate harder material such as metal . fig1 illustrates a flowchart of how the apparatus 401 can be utilized 1000 during an implant placement surgery . it will be appreciated that the steps can be modified , yet remain within the spirit of the exemplary embodiments herein . it should be noted that there are many variations to the workflow , and this chart is not intended to teach the surgical procedure itself . as is the case with the explanation of diagrams in fig1 and fig1 , the following explanation is directed to a multiple piece drill guide system 401 . prior to the surgery , all the parts of the drill guide set 401 are properly sanitized according to the material &# 39 ; s requirement . for example , if the parts are rapid prototyped with resin , cold sterilization methods may be appropriate . however , heat sterilization may be used for different materials with high temperature tolerance 1001 . lay a partial flap of the patient &# 39 ; s gum tissue to expose the jawbone in the area of interest 1002 . in rare occasions , the surgeon may choose to flap only the areas that the bone clasping contact portions of the devise will contact with , leaving the gum tissue over the implant sites . the base frame 200 or the single piece surgical drill guide 300 may be securely placed on the oral structure 100 and in contact with both gum tissue and the exposed bone ( see steps 1003 and 1003 b ). additional attachments may be added to the device for bone clasping . depending on the patient &# 39 ; s oral structure , anchor screws or pins may be used for securing the position of the device . bone adjustment or bone grafting may be done before or after the placement of the base frame 200 . if the bone adjustment is needed , the base frame may be used as a jig or an additional bone adjustment jig can be attached to the base frame 200 for this process . optionally , a modified denture duplicate attachment 500 ( fig5 ) can be used on the base frame 200 . in that case , verify the device &# 39 ; s poisoning with bite to secure the base frame 200 to the oral structure , and then remove the attachment portion , leaving the base frame 300 on the oral structure 1009 and 1010 . after the base frame is securely placed , attach the drill guide section 300 to the base frame 200 ( step 1004 ) in order to drill osteotomies into the jawbone ( step 1005 ). the interchangeable additional drill guide sections may be used to complete the osteotomies 1011 . when finished , the drill guide section 400 may be removed from the base frame ( 200 ), and the implants may be placed into the jawbone ( see step 1006 ). should a certain type of surgical guide tube system be adopted into the drill guide frame 300 , the surgeon may place the implants through the drill guide tube bushings 1009 prior to the removal of the drill guide section 400 . the surgeon may choose to take a fixture level index for the record of implant positions at this point . in that case , he / she may be able to do so by altering the surgical guide section 400 into a transfer jig tray or by using a separate transfer jig tray that attaches to the base frame 200 ( see step 1012 ). one advantage of utilizing the drill guide section 400 is that the actual positioning information can be easily transferred back to the physical anatomical model . the model can be adjusted , if necessary , and the prosthesis can be created on it without making a separate brand new model . after the base frame is removed 1007 the surgeon can complete the surgery by placing cover screws or healing caps , and suturing the gum tissue over the cover screw or around the healing caps . alternatively , the immediate loading procedure may be followed , and the prosthesis that had been designed on the digital or the physical anatomical model can be placed 1008 .
a dental surgical drill guide assembly and method includes a surgical guide housing and a base frame that fits to both gum tissue and one or multiple small areas of jawbone . the apparatus may be configured to accurately place dental implants according to planned positions . such apparatus may increase the stability of the surgical guide by clasping and / or contacting the jawbone , while improving the overall fit and minimizing the need of invasive surgery and flapping by also clasping and / or contacting selected areas of the gum tissue at the same time . self - locking alignment members aid in easy removal , and re - installation , of the surgical guide housing to the base frame .