the density of bone site is a determining factor in treatment planning and initial progressive bone loading during prosthetic reconstruction . amongst the various classifications proposed , the misch 's and lekholm 's and zarb 's categorization of bone quality were more clinically applicable .
but , irrespective of the difference , all the bone types were treated with the standard protocol . in 1988 , misch described four groups independent of the regions of the jaws , based on macroscopic cortical and trabecular bone characteristics as follows : d1 : dense cortical bone ; d2 : thick dense to porous cortical bone ; d3 : thin porous cortical bone on crest ; d4 : fine trabecular bone and d5 : immature bone .
it is difficult to obtain anchorage in the less dense bone which results in low success rate . in a meta - analysis
, it was found that bone quality was responsible for 7.7% of all implant losses .
compromised bone may cause both early and late failures . with the ever - increasing number of manufacturers with innovative fixture designs and patients who accept the modality as a permanent rehabilitation for missing teeth
, the greater research with the improved designs on the soft bone is the need of the hour .
the present study was done to determine the survival of maestro in the d3 and d4 jaw bone by evaluating annual peri - implant soft tissue health and the bone height around the implants . because the bone is strongest in compression and 65% weaker in shear , a square thread shape is designed such that it results in 10 times less shearing force than with a conventional v - shaped thread .
fourteen patients ( 10 males and 4 females ) were selected from the out patient department of periodontics , bapuji dental college and hospital , davangere , india on a written consent - to - treat agreement .
the patients aged in the range of 1850 years with a single missing tooth , well - compliant with the oral hygiene instructions and with good dental and general health ; but who did not present with parafunctional habits , insufficient interarch space , diabetes and heavy smoking were subjected to computerized tomographic ( ct ) scanning as per the standard protocol .
the distance from contiguous tooth and proximity from the vital anatomical structures was assessed first .
it is established in the literature that the d3 and d4 type is found mostly in the posterior maxilla , anterior maxilla and posterior mandible . as per the hounsfield units calibration ; six , five and three cases were selected for the anterior maxilla , posterior maxilla and posterior mandible respectively [ figures 1 and 2 ] .
additionally , the pretreatment records included the periodontal status , diagnostic casts , periapical and panoramic radiographs , clinical photographs and surgical stent .
computed tomography case i : scout view and bone density at proposed implant crestal ( c ) , middle ( m ) and apical ( a ) level computed tomography case ii : scout view and bonedensity at proposed implant crestal ( c ) , middle ( m ) and apical ( a ) level the preliminary impressions were made to fabricate a surgical guide stent . on the surgery day , the patients were covered with a surgical drape and were made to rinse with 10 ml of 0.2% chlorhexidine gluconate solution .
this was followed by the surgical extraoral scrubbing with betadine ( 5% povidine iodine ) . under the appropriate block
the osteotomy was done using a nsk 20:1 gear reduction hand piece attached to atr physiodispenser at 1300 rpm starting speed under copious sterile saline irrigation [ figures 3 - 4 ] .
case 1 : preoperative with stent , drilled osteotomy site , implant inserted , cover screw placed , crown fabricated on abutment , crown cemented case 2 : pilot drill passed through stent , drilled osteotomy site , implant inserted , cover screw placed , flap repositioned , permucosal extension placed at uncovery stage , abutment milled for crown fabrication , crown delivered in occlusion following the drill sequencing on the manufacturer 's instructions , the maestro implants of selected size was removed from the sterile vial and engaged through a premounted abutment onto a hand piece adaptor . it was taken utmost care not to touch the implant and that no thread on the implant body is visible outside the bone crest .
thus , the final primary stability of the implant was checked at the end of the insertion .
the particular system was opted for the study as it a root form , fine pitched threaded implant to provide a greater contact surface area .
it is hypothesized that functional surface area will affect clinical health in poor - quality bone .
a 0.050  hex driver was used to remove the abutment mount and replaced with the cover screw .
the flap was then repositioned , sutured and covered by a periodontal pack ( coe pak ) .
the cover screws were exposed after 4 and 6 months in mandible and maxilla respectively to be replaced by permucosal extension , followed by impressions with the medium viscosity elite implant ( zhermack italy ) using a custom tray ; and the cemented metal - ceramic crown was delivered finally .
the clinical parameters were analyzed statistically and a 3 , 6 , 9 and 12 months record of the modified plaque index , gingival index , modified sulcular bleeding index ; and clinical implant mobility scale was done .
the standardized long cone periapical radiographs using long cone were recorded similarly [ figure 5 ] .
iopa radiographs compared at implant placement with 12 months post - operative : case1 , case2 , case 3 , case 4 , case 5 ; and case 6
out of the 11 implants placed in the maxillary and three in the mandibular jaw , one failed after 3 months .
out of the 13 cases included in the study , one dropped out and was excluded after 4 months .
plaque score [ table 1 ] and gingival index values [ table 1 ] showed a slight reduction at continuous intervals until 12 months postoperatively but was statistically insignificant .
the mean sulcus bleeding score [ table 1 ] reduced to 0.12  0.17 at the end of 1 year , which was statistically significant .
there was a decreased mean implant probing depth [ table 2 ] from the baseline .
the mean vertical bone level changes ( combined mesial and distal ) were reported reduced from 1.19  1.35 mm at the baseline to 1.37  0.89 mm at the end of 1 year . [ table 3 ] .
thus , a significant correlation was analyzed between the plaque index and the peri - implant bone loss [ table 4 ] ; and an implant success of 92.3% in low - density bone in the study .
posttreatment changes in modified plaque , gi and msbi score posttreatment changes in ipd radiographic peri - implant bone level assessment relationship between clinical and radiographic parameters
is said to be successful clinically if it is immobile , with the absence of associated pain , infections , neuropathy , and paresthesia .
a predictable survival in all the bone densities was evaluated previously using fixture from the system used in this study .
an implant or a tooth diagnosed as a clinical failure is easier to describe than one that is a success .
although , implant failure can be attributed to many factors , most variables can be eliminated if accepted surgical procedures are followed .
while the very dense bone at the implantation site can affect osseointegration by time of the osteotomy , the compromised bone , on the other hand , may cause both early and late failures . in a landmark study ,
the authors reported a 35% branemark 's fixture loss in any region of the mouth when bone density was poor .
similar results were observed by another author who reported 78% of failures in the soft bone types .
however , the present study refuted the hypothesis that implants are the least predictable in compromised host bone that was preassessed with ct scan in all patients .
wide implants as were used in this study are advocated for the situation . in a study
, the authors claimed that the design alterations in the form of wide diameter fixtures were more suited to treat the areas of inadequate bone height , areas of poor bone quality and for the immediate replacement of nonosseointegrated implants . unlike the original branemark screw , which had a v - shaped thread pattern , the maestro implant has a square crest and a flank angle of 3 that serves to decrease the shear force and increase compressive load .
the patient was noncompliant to the attempt at tobacco cessation prior to inclusion in the study .
the findings of the study corroborated with the previous retrospective evaluation , in which authors claimed an overall failure rate of 11.3% with branemark systems implants placed in smokers .
the reason stated by the authors was that the smokers and ex - smokers had lower trabecular bone mineral content when compared to never - smokers .
an overall success of 92.3% and 100% success in posterior sites was evaluated 1 year postoperatively . except for one case , which was deemed a failure ,
all the implants showed an absence of clinical mobility . a mean mesial peri - implant bone gain mesially , but slight average mean annual bone loss ( 0.18 mm with a standard deviation of 0.95 ) was reported . within the limits of the study , a significant correlation between plaque index and the mean peri - implant annual bone loss was shown .
a few more studies with the similar implant type and incorporating a larger sample size , as well as greater follow up post loading are needed in the future .
 aim : in the less dense bone , it is difficult to obtain implant anchorage . the present study was undertaken to determine the survival rate of maestro implants placed in d3 and d4 bones.materials and methods : fourteen patients ( 10 males and 4 females ) were selected for the study and implants were evaluated for posttreatment changes in at 3 , 6 , 9 and 12 months from implant placement . 
 the implant probing depth and mobility were recorded 3 and 6 months after prosthesis placement . 
 also , peri - implant bone level was assessed at the baseline and 12 months postoperatively , followed by a statistical analysis.results:the mean plaque and gingival indices showed a reduction at repeated intervals . 
 the mean sulcular bleeding showed a slight reduction which was statistically significant . 
 an overall mean bone loss was observed after 12 months follow - up , which was statistically not significant . 
 the overall survival rate of implants was reported as 92.3%.conclusion : the specific implant used in the study is advantageous in the soft bone condition.clinical significance : although , there is a great evidence of implant failure in compromised jaw quality , the newer designs and approaches suggest that the poor quality is not a contraindication . 
Clinical Significance:
Introduction
Materials and Methods
Results
Discussion
Conclusion