Single-crown restorations in premolar-molar regions: short (<= 6.5) vs longer implants: retrospective cohort study

Ani uae al. In e na ional Jou nal o Implan Den is y (2022) 8:40 h ps://doi.o g/10.1186/s40729-022-00438-y RESEARCH Single-c own es o a ions inp emola – mola egions: sho (≤ 6.5) s longe implan s: e ospec i e coho s udy Edua do Ani ua1,2*† , Mohammad Hamdan Alkh aisa 2 and Asie Eguia1,3† Abs ac Pu pose: To compa e he su i al, changes in ma ginal bone le el and p os he ic complica ions a e o sho (≤ 6.5 mm) and longe implan s (≥ 7.5) suppo ing a single-c own es o a ion in he maxilla y/mandibula p emola o mola egion. Me hods: This coho s udy was conduc ed ollowing he STROBE s a emen ecommenda ions o obse a ional s udies. Clinical ou comes o 88 sho implan s in 78 pa ien s and 88 long implan s in 88 pa ien s we e examined. All he implan s had been placed by he same su geon and es o ed ollowing he same p os he ic concep ; using a ansepi helial abu men (in e media e abu men ) and a sc ew e ained es o a ion. Resul s: All he implan s we e in unc ion a e he ollow-up pe iod since inse ion (median: 31 mon hs; ange 11 o 84 o SiG s median: 35 mon hs; ange: 6–117 o CG; p = 0.139). No s a is ical di e ences (p = 0.342) we e obse ed ela ed o p os he ic complica ions (sc ew loosening 2/88 s 5/88 CG, ce amic chipping 1/88 s 0/88, empo a y c own esin chipping 1/88 s 0/88 o SiG and CG, espec i ely) o ela ed o ma ginal bone le el (Mesial o Dis al MBL ≥ 2 mm in 1/88 implan s o SiG s 3/88 o CG; p = 0.312). Conclusions: Wi hin he limi a ions o his s udy, no su i al di e ences ha e been obse ed be ween sho implan s and longe implan s in single-c own es o a ions in pos e io maxilla/mandible. Keywo ds: Den al implan s, Sho implan s, Ma ginal bone loss, C own- o-implan a io © The Au ho (s) 2022. Open Access This a icle is licensed unde a C ea i e Commons A ibu ion 4.0 In e na ional License, which pe mi s use, sha ing, adap a ion, dis ibu ion and ep oduc ion in any medium o o ma , as long as you gi e app op ia e c edi o he o iginal au ho (s) and he sou ce, p o ide a link o he C ea i e Commons licence, and indica e i changes we e made. The images o o he hi d pa y ma e ial in his a icle a e included in he a icle’s C ea i e Commons licence, unless indica ed o he wise in a c edi line o he ma e ial. I ma e ial is no included in he a icle’s C ea i e Commons licence and you in ended use is no pe mi ed by s a u o y egula ion o exceeds he pe mi ed use, you will need o ob ain pe mission di ec ly om he copy igh holde . To iew a copy o his licence, isi h p:// c ea i eco mmons. o g/ licen ses/ by/4. 0/. In oduc ion Too h loss leads o changes in he in eg i y o he al eo- la bone and so issues [1, 2]. The healing o ex ac ion socke s leads o his ological and dimensional changes in he emaining al eola idge [1–4]. P og essi e a o- phy o he al eola p ocess begins a his momen bo h ho izon ally and e ically. Reso p ion o he al eola idge occu s due o a combina ion o di e en ac o s, such as loss o he pe iodon al ligamen (and lack o he ascula iza ion o he bundle bone), loss o unc ion (and he s imulus on he bone), ac u es in he al eola wall du ing ex ac ion o he subsequen occu ence o in ec- ious p ocesses [1–4]. The physiological pos -ex ac ion eso p ion (RRR, Residual Ridge Reduc ion) [5] can hinde he implan ehabili a ion o missing ee h. I no only a ec s he a ailable olume, bu also he densi y o he emaining bone [5]. These changes could hampe he subsequen placemen o an implan in an op imal posi ion o a ec he es he ic esul s. [6] Clinicians a e o en aced wi h he challenge o ea - ing pa ien s wi h se e e e ical bone a ophy. Di e en ea men op ions allow he use o s anda d implan s in he pos e io egion whe e he ne e canal o he Open Access In e na ional Jou nal o Implan Den is y †Edua do Ani ua and Asie Eguia con ibu ed equally o he wo k *Co espondence: edua do@ undacionedua doani ua.o g 1 Clínica Edua do Ani ua, Jose Ma ia Cagigal Kalea, 19, 01007, Vi o ia-Gaz eiz, Ála a, Spain Full lis o au ho in o ma ion is a ailable a he end o he a icle Page 2 o 8 Ani uae al. In e na ional Jou nal o Implan Den is y (2022) 8:40 maxilla y sinus limi he esidual bone heigh , such as guided bone egene a ion (GBR), maxilla y sinus g a - ing, inlay o onlay bone g a , dis ac ion os eogenesis, ne e la e aliza ion o o he s [7, 8]. These echniques equi e g ea e knowledge and su gical skills on he pa o he p o essional and po en ially inc ease he compli- ca ion a e [9–12]. Recen ad ances in implan design and sizing (sho , ex a-sho implan s) ha e p o ided new solu ions and al e na i es o ha e allowed op imi- za ion o exis ing ones [13–15]. In addi ion o acili a e he p ocedu es, he use o sho implan s educes he isk o eaching ana omical s uc u es a he ime o d illing, minimizes he numbe o su ge ies, educes he ime and cos o ea men , and sa es he need o bone augmen a- ion. [7, 16–18] In cases o e ical a ophy, he p os he ic space is la ge hus inc easing he c own- o-implan a io. Fo - me ecommenda ions abou he ideal p opo ions seem ou da ed in sigh o he di e se clinical and biomechani- cal s udies demons a ing he sa e y and good clinical pe o mance o sho and ex a-sho implan s [19, 20]. C own- o-implan a ios anging om 0.9 o 2.2 did no in luence he occu ence o echnical o biological com- plica ions [21]. Indeed, i has been claimed ha wi hin he ange o 0.6 o 2.36, he highe he c own- o-implan a io, he less he pe i-implan ma ginal bone loss (MBL) [20]. As he leng h o he implan is educed, i has been sugges ed o inc ease he diame e o enhance he bone– implan con ac and op imize he dis ibu ion o s ess in he bone, pa icula ly in cases o low bone densi y. [22] Sho implan s a e no limi ed o cases o limi ed a ail- able bone. Cu en ly, sho implan s can be p e e ed o main ain as much p is ine bone as possible, e en when s anda d implan s could be housed. [23, 24] Some au ho s epo ed ha sho implan s could ha e lowe su i al a es han s anda d implan s [25, 26] bu ecen sys ema ic e iews ha e shown ha sho implan s had a be e o equal pe o mance compa ed wi h s and- a d [27–29] and did no seem o ha e a signi ican in lu- ence on ma ginal bone loss [30]. Se e al sys ema ic e iews and me a-analysis ha e been conduc ed o cla i y he con o e sies on he clinical pe o mance o sho implan s [25, 31–34] bu hei esul s should be indi idu- ally in e p e ed wi h cau ion o assess he e en ual p es- ence o uncon olled con ounding ac o s in he included s udies [31] (as s udies including bo h splin ed and non- splin ed es o a ions, implan s placed in bo h g a ed o p is ine bone, di e en implan designs and su aces o di e en ypes o es o a i e design). The e is also ano he con o e sy ega ding he clas- si ica ion o sho implan s ha could esul in a mis- in e p e a ion o he esul s. While some au ho s conside ed sho implan s hose unde 10mm [35, 36], o he s conside ed a leng h unde 8mm [37] and mo e ecen ly, o he s unde 6.5mm [38] o 6mm. [39, 40] Recen e idence om clinical ials has shown he need o mo e s udies and longe pe iods o ollow-up be o e he ecommenda ion o sho implan s o suppo single- c own es o a ions [19, 40]. The objec i e o his s udy has been he compa ison be ween sho implan s and longe implan s in e ms o implan su i al, ma ginal bone emodeling and p os he ic complica ions o single- c own es o a ions. Ma e ials andme hods S udy design The p esen unicen ic obse a ional e ospec i e s udy was conduc ed ollowing he STROBE s a emen ecom- menda ions o obse a ional s udies and in compliance o he p inciples o he Decla a ion o Helsinki on clinical esea ch in ol ing human subjec s. Be o e s a ing, he pe mission o he e hics commi ee was ob ained om he Basque d ug esea ch commi ee. Sample size es ima ion A s udy o a con inuous esponse a iable o ma ched pai s o s udy subjec s was planned. The sample size was es ima ed based on p e ious bone loss da a a 12-mon h ollow-up indica ing ha he di e ence in esponse o ma ched pai s was no mally dis ibu ed wi h a s anda d de ia ion o 0.4320 [41]. I he ue di e ence in ma ginal bone loss a 12mon hs o ma ched pai s was 0.13, 88 pai s o implan s should be necessa y o ejec he null hypo hesis ha his di e ence in esponse is ze o wi h a p obabili y (powe ) o 0.8. The p obabili y o ype I e o associa ed wi h his es o he null hypo hesis was 0.05. Pa ien s Da a we e e ospec i ely collec ed om 88 sho (≤ 6.5 mm; 78 pa ien s) and 88 longe implan s (≥ 7.5mm; 88 pa ien s) andomly selec ed om a coho o 16.780 implan s placed om 2012 o 2019 a he same cen e (Edua do Ani ua Clinic, Vi o ia, Spain). A e sample size es ima ion, his coho was di ided in wo g oups (sho implan g oup; SIG and con ol g oup; CG) and simple andom sampling was conduc ed using he SPSS so wa e, (SPSS o Windows, Ve sion 15.0. Chi- cago, SPSS Inc) o selec 88 implan s o m each g oup. The inclusion c i e ia we e: – Implan s placed bo h in maxilla o mandible – Implan s suppo ing a single-c own sc ew- e ained, es o ed using a ansepi helial (in e media e abu - men ). – Pa ien s o e 18yea s Page 3 o 8 Ani uae al. In e na ional Jou nal o Implan Den is y (2022) 8:40 To add ess sou ces o bias, all pa ien s included in his s udy had been p e iously ea ed by he same eam, using he same implan sys em (UnicCa®, BTI Bio ech- nology, Vi o ia, Spain) and he same su gical and p os- he ic p o ocols. All he ea men s we e pe o med ollowing he usual clinical p ac ice o he pa icipa ing cen e o he inse ion and subsequen loading o sho and s anda d implan s in he mandible and/o maxilla. Da a collec ion me hods The ou comes measu ed we e su i al (p esence o he implan a he las isi ), MBL and p os he ic ( echnical) complica ions. The bone le el assessmen was pe o med e ically measu ing he dis ance om he bone c es o he i s bone-implan con ac bo h mesially and dis- ally. Measu emen s o es ima e MBL we e pe o med a loading ime and a he ime o he las a ailable adio- g aph using he Sidexis so wa e (Den sply Si ona; Yo k, US) and he leng h o he implan was used as calib a o . Among he echnical complica ions sc ew loosening/ b eak and ce amic/ esin chipping we e conside ed. O he clinically ele an a iables eco ded we e implan diame e , loca ion, inse ion o que, bone ype, sex and age, esidual bone heigh , ype o an agonis ee h and he need o addi ional su gical echniques. Follow- up ime was calcula ed since implan inse ion (un il las ecall) and implan loading (un il las ecall). The c own- o-implan a io was de e mined by di id- ing he leng h o he c own oge he wi h he ansepi he- lial (in e media e) abu men by he leng h o he implan . Residual bone heigh was measu ed om he bone idge c es o he maxilla y sinus/ne e canal a he implan posi ion, using he adiog aphy ob ained p e iously o he su ge y. In o ma ion abou smoking habi , alcohol in ake, dia- be es o hype ension was also e ie ed om medical eco ds. Bone ype quali y [42] was a ed wi h he aid o compu e so wa e (BTI Scan, BTI Bio echnology, Vi o- ia, Spain). S a is ical analysis A s a is ical analysis was pe o med using specialized so wa e (SPSS o Windows, Ve sion 15.0. Chicago, SPSS Inc). Ca ego ical a iables we e exp essed in abso- lu e and ela i e equencies. Con inuous a iables we e exp essed as median and ange. Be o e s a is ical analy- sis, he no mal dis ibu ion o he con inuous a iables was e alua ed using he Saphi o–Wilk no mali y es . S a is ical di e ences be ween ca ego ical a iables we e pe o med by he Chi-squa e es , and s a is ical di e - ences be ween dicho omous and con inuous ca ego ical a iables we e pe o med wi h he Mann–Whi ney es . The e ec o he c own o implan a io on he ma ginal bone loss was assessed by linea eg ession analysis. The s a is ical signi icance was se a p < 0.05. Resul s The s udy included 176 den al implan s placed in 166 pa ien s ha complied wi h he inclusion/exclusion c i- e ia. The Sho implan G oup (SiG) was composed by 88 sho implan s (≤ 6.5mm) placed in 78 pa ien s (53 emales; 35 males) and he Con ol G oup (CG) was com- posed by 88 implan s (≥ 7.5mm) placed in 88 pa ien s (52 emales; 36 males). Fu he demog aphic da a a e p esen ed in Table1. F om he SiG, 71 implan s we e 6.5mm-leng h and 17, 5.5mm-leng h. A ending o hei loca ion, 4 co e- sponded o Uppe P emola s (UP), 3 o Lowe P emola s (LP), 52 o Uppe Mola s (UM) and 29 o Lowe Mola s (LM). Figu es1,2. F om he CG, 69 we e 7.5-leng h, 17 8.5 mm-leng h and 2 we e 10 mm-leng h, and co e- sponded o 23 UP, 11 LP, 20 UM and 34 LM. Diame e o he implan s is p esen ed in Fig.3. The diame e o SiG implan s was highe (p < 0.001). Residual bone heigh was highe (p < 0.001) in CG (12.6 s 7.7mm) and c own- o-implan a io was highe (p < 0.001) in SiG (1.7 s 1.3mm). Figu e4. Con e sely, he e we e no s a is ical di e ences be ween bo h g oups ega ding inse ion o que, bone ype o an agonis ype. Fu he in o ma ion is a ailable in Table2. A he ime o implan placemen , no di e ences could be obse ed a ending o he numbe o implan s placed equic es al (− 0.5 o 0.5 mm), subc es al > 0.5 mm o sup ac es al < −0.5mm. in mesial, bu a highe p opo - ion o sho implan s (p ≤ 0.001) we e placed equic es al. A he ime o loading and las adiog aphy, no di e - ences in bone le el we e obse ed be ween bo h g oups in mesial. CG implan s we e mo e subc es al in dis al a loading ime han SiG implan s (p ≤ 0.001). In addi ion, du ing he las adiog aphy, a sligh di e ence (p < 0.05) in dis al bone le el was obse ed in a o o CG implan s. Mo eo e , he c own o implan a io did no signi ican ly a ec he ma ginal bone loss (p = 0.781). Table 1 Demog aphic da a CG con ol g oup, SiG sho implan g oup a Mann–Whi ney es b Chi-squa e es SiG CG p- alue Numbe o pa ien s (n = 176) 78 88 NA Numbe o implan s (n = 186) 88 88 NA Age (yea s; median ( ange) 56 (20 o 78) 53 (18 o 76) 0.159a Sex ( emales (males) 52 (36) 53 (35) 0.878b Smoke s 7 8 0.787b Page 4 o 8 Ani uae al. In e na ional Jou nal o Implan Den is y (2022) 8:40 Fig. 1 Le : 6.5 leng h implan placed in #3.7 posi ion. Cen e : 2 yea s la e ; single sc ew- e ained c own o e 4 mm. s aigh ansepi helial (in e media e abu men ). Righ : 6 yea s a e implan placemen . No ma ginal bone loss obse ed a e 6-yea ollow-up Fig. 2 Le : 8.5 leng h implan placed in #1.4 posi ion. Cen e : 2 yea s la e ; single sc ew- e ained c own o e 2 mm. S aigh ansepi helial (in e media e abu men ). Righ : 6 yea s a e implan placemen . No ma ginal bone changes a e 6-yea ollow-up 3.30 3.50 3.75 4.00 4.25 4.50 5.00 5.50 6.00 6.25 SiG (≤6.5mm) 23285932 22 41 CG (≥7.5 mm) 319128 6419 16 10 0 5 10 15 20 25 30 35 SiG (≤6.5mm) CG (≥7.5 mm) Fig. 3 Implan diame e . SiG (sho implan g oup), CG (con ol g oup) Page 5 o 8 Ani uae al. In e na ional Jou nal o Implan Den is y (2022) 8:40 The ollow-up o den al implan s, since inse ion had a median o 31 mon hs ( ange 11 o 84) o SiG and 35mon hs o CG ( ange 6–117). All he implan s om bo h g oup we e in unc ion a he las ecall (100% su i al) and he numbe o p os he ic complica ion did no s a is ically di e (3 e en s o SiG s. 6 o CG). A ending o he Heal h Scale o Den al Implan s [43], Success a e o SIG g oup was 100% and 98.9% o CG. No s a is ical di e ences in Ma ginal Bone Loss (MBL) we e obse ed ei he in Fig. 4 Le : 5.5 mm leng h implan placed in he #2.7 posi ion. Sc ew- e ained single-c own o e a 3 mm ansepi helial (in e media e abu men ). C own- o-implan a io: 1.84. Righ : 7.5 mm leng h implan placed in he same posi ion (#2.7). Sc ew- e ained single-c own o e a 3 mm ansepi helial (in e media e abu men ). C own- o-implan a io: 1.80 Table 2 Su gical da a, c own- o-implan a io, and ollow-up da a a Mann–Whi ney es b Chi squa e es G oup p- alue Expe imen al Con ol Residual bone heigh (mm; median ( ange)) 7.7 (4.2 o 17.6) 12.6 (7.7 o 20.4) 0.000a Inse ion o que (Ncm; median ( ange)) 42.5 (5.0 o 70.0) 35.0 (5.0 o 70.0) 0.188a Bone ype (numbe o implan s) Type I 4 4 0.234b Type II 44 49 Type III 33 22 Type IV 7 13 An agonis (numbe o implan s) Too h 63 66 0.609b Implan 25 22 C own o implan a io (median ( ange)) 1.7 (1.1 o 2.5) 1.3 (0.9 o 2.1) 0.000a Immedia e loading (numbe o implan s) 49 49 1.000b Follow-up since inse ion (mon hs; median ( ange)) 31 (11 o 84) 35 (6 o 117) 0.139a Follow-up since loading (mon hs; median ( ange)) 27 (4 o 84) 31 (6 o 67) 0.249a Follow-up o ma ginal bone le el (mon hs; median ( ange)) 24 (3 o 92) 30 (1 o 96) 0.095a Page 6 o 8 Ani uae al. In e na ional Jou nal o Implan Den is y (2022) 8:40 mesial o dis al be ween bo h g oups a e he ollow- up pe iod. The e we e no di e ences in he numbe o implan a eas (mesial/dis al) showing MBL ≥ 2mm (SiG 1/166; 6/166 CG). Addi ional in o ma ion abou he clini- cal pe o mance is a ailable in Table3. Discussion The esul s o he p esen e ospec i e coho s udy showed no di e ences in su i al, changes in ma ginal bone le els o p os he ic complica ions be ween SiG and CG implan s suppo ing a single-c own es o a ion o e a ansepi helial (in e media e abu men ) in pos e io maxilla o mandible. These esul s a e in line wi h hose o he sys ema ic e iew and me a-analysis published by Tolen ino da Rosa de Souza e al. [7] Sho implan s in pos e io single c own had simila su i al a es, low MBL and low p os he ic and su gical complica ions a e o a 1-yea ollow-up ime. On he con a y Xu e al. [41] on hei me a-analysis s a ed ha he su i al a e o sho implan s in he maxilla may be lowe han ha o long implan s, while in he mandible bo h ype o implan s showed simila su i al a e. Fu he mo e, sho implan s ha e been associa ed wi h lowe MBL and biological complica ions bu highe echnical complica- ions. I Wo h men ioning ha sho and longe implan de ini ion was di e en in hese s udies [7, 41]. Mo eo e , mos o au ho s selec ed a unique leng h in he SiG and a unique leng h in he CG ins ead o de ining a limi leng h be ween bo h g oups. The ype o included a icles (only RCTs [41] o CCTs and RCTs [7]), he a io o maxilla y/ mandibula implan s, he p opo ion o implan s placed wi h addi ional echniques, o he ollow-up pe iod could also explain he di e ences be ween bo h me a-analysis. Sys ema ic e iews compa ing Sho and S and- a d implan s including bo h splin ed and non-splin ed implan s [31, 44, 45] should be in e p e ed wi h cau ion as he biomechanical pe o mance o splin ed implan s is subs an ially di e en om non-splin ed ones. In mul i- ple es o a ions splin ed implan s can dispe se he s ess on each single implan he eby educing he implan o e load and he possible incidence o mechanical com- plica ions [7, 46, 47]. In ela ion o he biomechanical pe o mance o sho implan s suppo ing single c owns, simila ou comes ha e been epo ed when he implan is placed in he mos dis al posi ion in he a ch o be ween adjacen ee h o o he implan s. [48] Many a icles ha e been published compa ing he pe o mance o sho implan s in na i e bone s longe implan s along wi h sinus g a ing in he maxilla. A ecen umb ella e iew o me a-analysis om Ve omilla e al. [28] concluded ha sho implan s showed ewe biological complica ion a es, educed cos , and an o e - all simila sa is ac ion a e o he pa ien s. In he p esen s udy, he c own- o-implan a io o all he implan s in he CG whe e wi hin he anges ha ha e been s a ed no o nega i ely in luence he pe o mance o implan s; om 0.9 o 2.2 [21] o 0.6 o 2.36 [20]. F om he SiG, only 2/88 implan s sligh ly exceeded his second Table 3 Resul s. Da a ela ed o implan su i al, MBL (ma ginal bone loss) and p os he ic complica ions Ma ginal bone (MB) le el ((−): below he mos co onal pa o he implan shoulde ; ( +): abo e he mos co onal pa o he implan shoulde ) a Mann–Whi ney es b Chi squa e es G oup p alue Sho Implan s S anda d Technical complica ions (numbe o implan s) None 85 82 0.342b Sc ew loosening 2 5 Resin chipping 1 0 Ce amic chipping 0 1 Mesial MB le el (mm; median ( ange)) Loading 0.7 (− 0.7 o 2.5) 0.7 (− 0.4 o 2.3) 0.173a Las isi 0.8 (− 1.2 o 2.9) 0.6 (− 3.3 o 2.9) 0.262a Dis al MB le el (mm; median ( ange)) Loading 0.3 (− 2.5 o 2.3) 0.6 (− 1.3 o 2.3) 0.001a Las isi 0.4 (− 2.1 o 2.1) 0.5 (− 3.8 o 2.4) 0.018a Change in MB le el (mm; median ( ange)) Mesial 0 (− 1.5 o 1.3) 0.1 (− 4.0 o 1.4) 0.322a Dis al 0.1 (− 2.2 o 1.0) 0.1 (− 4.0 o 1.0) 0.758a Change in MB le el ≥ 2 mm Mesial 0 1 0.316b Dis al 1 3 0.312b Change in MB le el ≥ 3 mm Mesial 0 1 0.316b Dis al 0 1 0.316b Su i al (numbe o implan s) 88 88 NA Page 7 o 8 Ani uae al. In e na ional Jou nal o Implan Den is y (2022) 8:40 p e iously published ange and 5/88 he i s one. The di e ences be ween SiG and CG in he c own- o implan in he p esen s udy we e lowe han in o he s udies [20, 21] p obably because he leng h o he CG implan s was lowe . The use o ansepi helial abu men s in all he implan s p obably con ibu ed o achie e a low numbe o echni- cal complica ions in bo h g oups and helped o dissipa e implan loads hus posi i ely in luencing in he biologi- cal pe o mance oo [22, 49, 50]. This o al homogenei y in he ype o p os he ic es o a ion and in he ype o implan su ace oge he wi h a well-balanced sampling in ela ion o pa ien s´ sex and age, numbe o smoke s, bone ype, inse ion o que o ype o an agonis , a e ele an s eng hs o he p esen s udy. The unicen ic design o he s udy ensu ed ha all implan s we e placed and p os he ically ehabili a ed by he same eam, ollow- ing he same p o ocol. This could ha e helped o educe bias bu a he same ime he lack o da a om o he cen e s could be a he same ime conside ed a limi a- ion o he s udy. O he limi a ions o he s udy we e he limi ed ollow-up ime o he educed abili y o con ol con ounding ac o s o he e ospec i e designs. New long- e m p ospec i e s udies a e ecommended o con- i m hese esul s. Conclusions Wi hin he limi a ions o his s udy, sho (≤ 6.5mm) and s anda d (≥ 7.5mm) implan s suppo ing a single- c own es o a ion o e a ansepi helial (in e medi- a e abu men ) in he pos e io maxilla/mandible show simila clinical pe o mance (su i al, MBL, p os he ic complica ions). Acknowledgemen s No applicable. Au ho con ibu ions All au ho s ha e made subs an ial con ibu ions o he concep ion o design o he wo k o he acquisi ion, analysis, o in e p e a ion o da a o he wo k; AND d a ing he wo k o e ising i c i ically o impo an in ellec ual con en ; AND ha e gi en inal app o al o he e sion o be published; AND ag ee o be accoun able o all aspec s o he wo k in ensu ing ha ques ions ela ed o he accu acy o in eg i y o any pa o he wo k a e app op ia ely in es iga ed and esol ed. All au ho s ead and app o ed he inal manusc ip . Funding This esea ch did no ecei e any speci ic g an om unding agencies in he public, comme cial, o no - o -p o i sec o s. A ailabili y o da a and ma e ials The da a se s used and/o analysed du ing he cu en s udy a e a ailable om he co esponding au ho on easonable eques . Decla a ions E hics app o al and consen o pa icipa e The s udy p o ocol was app o ed by he e hical commi ee o he Uni e si y Hospi al o A aba (FIBEA-02-ER/22/Ex aco os). Consen o publica ion No applicable. Compe ing in e es s EA is he Scien i ic Di ec o and he p esiden o BTI Bio echnology Ins i u e, a den al implan company ha in es iga es in he ields o o al implan ology and PRGF-Endo e echnology, and he p esiden o Edua do Ani ua Founda- ion. MHA is a esea che (employee) a BTI Bio echnology Ins i u e. AE is a esea che a he Edua do Ani ua Founda ion. Au ho de ails 1 Clínica Edua do Ani ua, Jose Ma ia Cagigal Kalea, 19, 01007, Vi o ia-Gaz eiz, Ála a, Spain. 2 BTI-Bio echnology Ins i u e, Vi o ia-Gaz eiz, Ála a, Spain. 3 Uni- e si y o he Basque Coun y UPV/EHU, Leioa, Vizcaya, Spain. Recei ed: 7 June 2022 Accep ed: 8 Sep embe 2022 Re e ences 1. A aújo MG, Sil a CO, Misawa M, Sukeka a F. Al eola socke healing: wha can we lea n? Pe iodon ol. 2000;2015(68):122–34. 2. Jung RE, Ioannidis A, Hämme le CHF, Thoma DS. Al eola idge p ese a- ion in he es he ic zone. Pe iodon ol. 2000;2018(77):165–75. 3. 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