J B agh College D entistry Vol. 27( 1) , M arch 2015 H istological and R estorative D entistry 26 Histological and histomorphometric analysis of strontium chloride coated commercially pure titanium implant compared with hydroxyapatite coating Ghasak H. Jani, B.D.S. (1) Shatha S. Al-Ameer, B.D.S., M.Sc. (2) Salam N. Jawad, B.D.S., M.Sc. (3) ABSTRACT Ba c kg ro und : In re c e nt ye a rs, the im m e d ia te lo a d ing o f d e nta l im p la nts ha s b e c o m e m o re a c c e p te d a s a sta nd a rd p ro to c o l fo r the tre a tm e nt o f the e d e ntulo us a re a . Suc c e ss in im p la nt d e ntistry d e p e nd s o n se ve ra l p a ra m e te rs tha t m a y im p ro ve p he no m e no n o f o sse o inte g ra tio n a nd ne w b o ne fo rm a tio n in c lo se c o nta c t with the im p la nt. The a im o f stud y wa s to e va lua te the e ffe c t o f stro ntium c hlo rid e c o a ting o f sc re w sha p e c o m m e rc ia lly p ure tita nium d e nta l im p la nt o sse o inte g ra tio n a t b o ne - im p la nt inte rfa c e b y histo m o rp ho m e tric a na lysis a nd c o m p a re w ith hyd ro xya p a tite c o a ting a t 2 time p e rio d s (2 we e ks a nd 6 we e ks). Ma te ria ls a nd m e tho d s: Ele c tro p ho re tic De p o sitio n Te c hniq ue (EPD) w a s use d to o b ta in a unifo rm c o a ting la ye r o n c o m m e rc ia lly p ure tita nium sc re w s. The tib ia o f 4 w hite Ne w Ze a la nd ra b b its w a s c ho se n a s im p la nta tio n site s. Ea c h tib ia o f ra b b it re c e ive d two sc re ws, o ne stro ntium c hlo rid e c o a te d a nd o ne hyd ro xya p a tite c o a te d a nd a to ta l 30 histo lo g ic a l se c tio ns w e re o b ta ine d fo r e a c h c o a ting m a te ria l in e a c h p e rio d o f tim e . Histo m o rp ho m e tric a na lysis wa s p e rfo rme d to me a sure ne w b o ne fo rme d ra tio b e twe e n imp la nt a nd o rig ina l b o ne , a fte r 2 a nd 6 we e ks he a ling p e rio d s. Re sults: The re w a s inc re a se d in ne w b o ne fo rm a tio n ra tio fo r the stro ntium c hlo rid e c o a te d im p la nts tha n hyd ro xya p a tite c o a te d imp la nts a nd o ve r the two p e rio d s o f time . The re wa s a n inc re a se in the ne w b o ne fo rma tio n ra tio a t b o ne -im p la nt inte rfa c e w ith tim e . C o nc lusio n: C o a ting c o m m e rc ia lly p ure tita nium im p la nt w ith stro ntium c hlo rid e w a s m o re e ffic ie nt in inc re a sing o sse o inte g ra tio n a t b o ne im p la nt inte rfa c e tha n hyd ro xya p a tite , w hic h w a s d e m o nstra te d b y hig he r ne w b o ne fo rm a tio n a nd m a tura tio n a t the tw o p e rio d s o f tim e 2 w e e ks a nd 6 w e e ks a fte r im p la nta tio n. Keywords: Histo m o rp ho m e tric , c o m m e rc ia lly p ure tita nium , stro ntium c hlo rid e , hyd ro xya p a tite . (J Ba g h C o ll De ntistry 2015; 27(1):26-31). INTRODUCTION Implants are one of the most an important therapeutic surgical procedures providing both an aesthetic and functional alternative to tooth replacement. Procedures involving dental implants have grown steadily, rising consistently over the last 20 years to reach approximately one million performed annually worldwide. (1,2) Dental implants vary in material, dimensions, geometries, surface properties and interface geometry, so today the dentist needs to select from more than 2,000 different dental implants and abutments in a specific treatment situation. (3) The success of implant fixation is highly dependent on the implant surface poperties to improve integration by different surface coating technologies for promoting osseointegration . (4) osseointegrationwas defined as a direct structural and functional connection between ordered living bone and the surface of a load-carrying implant. (1) Master Student. Department of Prosthodontics, College of Dentistry, University of Baghdad. (2) Professor, Department of Prosthodontics, College of Dentistry, University of Baghdad. (3) Pathologist. Ministry of Health. Baghdad, Iraq In practice, this means that in osseointegration there is an anchorage mechanism where by nonvital components can be reliably and predictably incorporated into living bone and that this anchorage can persist under all normal conditions of loading. (5) A relatively new anti-osteoporotic drug, strontium ranelate (protelos), is proposed to induce, in contrast to other anti-osteoporotic drugs (like bisphosphonate), simultaneously both an anti-resorption and bone forming effect. (6,7) Strontium is a trace metal in human body and its physiologically stable divalent cationic form (Sr +2 The ion has a relatively high affinity to bone and may replace Ca in apatite crystals by ion exchange. Strontium ranelate contains two Sr +2 ions and ranelic acid. (8,9) Histomorphometric measurement is a representative test in studying the nature of the implant-tissue surface and has been used by several authors to evaluate the bone implant interface. (10) Atsumi et al. categorize it as the method of highest reliability to evaluate implant stability that can be performed at any time (pre, intra or post) of the implantation. (11) The purpose of this study was to make histological and histomorphometric analysis of strontium chloride SrCl 2 ) and hydroxyapatite