24 대한치과이식 ( 임프란트 ) 학회지 2009;28(1):24-28 치아결손부에자가치아이식술을시행한치험례 리빙웰치과병원구강악안면외과손효정, 장호열, 금윤선, 김현철, 이상철 Ⅰ. 서론 자가치아이식은동일개체의구강내에서치아를다른부위로옮겨생착시키는술식이다 1). 선천적치

24 대한치과이식 ( 임프란트 ) 학회지 2009;28(1):24-28 치아결손부에자가치아이식술을시행한치험례 리빙웰치과병원구강악안면외과손효정, 장호열, 금윤선, 김현철, 이상철 Ⅰ. 서론 자가치아이식은동일개체의구강내에서치아를다른부위로옮겨생착시키는술식이다 1). 선천적치아결손부가존재하거나외상으로인해치아결손부가생긴경우, 치관-치근파절증례, 치경부우식이나치근흡수가치조골하방으로연장된증례등에서치아상실부위에대한환자의심미적욕구와기능을회복하는방법으로제3대구치를이용한자가치아이식이시행될수있으며치아의발육정도, 이식치의형태, 이식와의감염여부, 술중외상, 고정의형태등이예후에영향을미친다 2). 자가치아이식은 1554년 Ambroise Pare에의해처음문헌에보고되었고 3) 1950년에서 1955년사이에 Apfel, Fong, Hale, Clark등에의해보존적치료가불가능한제 1 대구치를발거하고맹출전의제 3 대구치를이식하는방법에대한세부적인술식과정에대해보고된바있다 4-7). Apfel과 Fong은 2-3mm 4,5), Hale와 Clark는 3-5mm 정도의치근발육이남아있을때가이식하기에적당한시기라하였고 6,7) 1980년 Konigrsberg는치근발육이 3/4정도진행되었을때가이식하기에적당하며고정을위해아크릴이나금속을이용한스프린트를추천하였다 8). 그러나최근연구들에의하면스프린트를이용해고정을시행하는것이치주조직의치유에도움이되지않 Corresponding author : Hyo-Jeong Son Department of Oral and maxillofacial surgery, LivingWell Dental Hospital 031-916-8020 E-mail : livingwell@paran.com Received March 6, 2009 Revised May 12, 2009 Accepted May 27, 2009 으며오히려치환성흡수를증가시킨다고하였다 9). 1950년대에는시행후에불충분한치근발육, 치근흡수등의부작용으로 50% 정도의낮은성공률을보고하였으나 10) 최근치아이식과관련하여술식및치근막치유에대한연구의발전으로자가치아이식의성공률이높아졌고, Andreasen은 96% 의높은성공률을보고하였다 11). 자가치아이식이성공적으로이루어진다면심미적인요구를만족시킬뿐만아니라악궁의형태를유지하며성장이남아있는아동에있어치조골의발육을기대할수있다. 또한저작, 발음등의기능적인요구를만족시킬수있다는장점이있다 12). 본증례는치근단발육이미완성인제3대구치를이용하여제 2대구치부위로자가치아이식을시행한것으로이식후치아생활력이유지되고정상적인저작기능을수행하게된경우에대한보고이다. Ⅱ. 증례보고 17세남성환자가 #47의동통을주소로내원하였다. 현증으로 #47의이차우식및방사선투과성치근단병소를보였고 #48이치근단미완성상태로매복되어있었다. #47의보존적치료를통한수복이불가능할것으로판단되어 #47의발치와 #48의자가치아이식을계획하였다 (Fig. 1). 2% 리도카인 (1:10만에피네프린포함 ) 을사용하여국소마취후 #47의발치및치근단병소의소파술을통해이식와를형성하였다. 공여치로선택된 #48의조심스러운발치후이식와에접합시키고이식된치아는강선고정없이봉합만으로고정하였다 (Fig. 2 A.

치아결손부에자가치아이식술을시행한치험례 25 Fig. 1. Preopertive panoramic radiograph. Fig. 3. Postoperative panoramic radiograph. Fig. 2. A. Tansplantation of donor tooth. Fig. 4. Mobility test with Periotest. Fig. 2. B. Fixation with suturing. B., 3). 중심교합에서 Shimstock이자연스럽게빠져나올정도로교합조정을시행하였고, 치근단미완성치아였기에치수재생을동반한치근단의완성을기대하였다. 이식 2년후치수생활력및치근단발육이유지되었으며 periotest를이용한치아의동요도검사시 +0.6로정상적인동요도를보였다 (Fig. 4). 치근흡수가보이지않았으며정상적으로교합기능을수행하였다 (Fig. 5). FIg. 5. Radiograph obtained 2 years later. Ⅲ. 총괄및고찰자가치아이식후이식치아의치수에는허혈성변화가일어나고치근이완성된치아에비해치근이미완성된치아를이식하는경우치수재생의가능성이높다 12). 하지만, 치근의발육이미약할경우에는오히려발육정지나부분발육이일어날가능성이높아지며, 약 3/4정도의치근발육이일어났을때가이식하기에가장적절한시기로알려져있다 1). 또한치근단이완성된치아일지라도

26 손효정, 장호열, 금윤선, 김현철, 이상철 치근단공이 1mm 이상으로열려있을때는이식후치수재생을기대할수있다. Andreasen 등은치근단공이 1mm 이하인경우는 10%, 1-2.9mm 이하는 80%, 3mm 이상에서는 95% 의치수재생의가능성을보고하였다 11). 자가치아이식후치수재생과치주조직의치유를위해서는공여치의선택이중요하고, 이때공여치의치관부와치근부의해부학적형태를고려해야한다. 공여치의치관부는필요에따라보철적인수복이가능하지만, 치근막의혈류공급을위해수용부에적합한이식치를선택하는것이필요하며이식치의치근부는이식와의치조골에 1mm 정도의간격을두고느슨하게적합시키는것이치주인대의치유에유리하다 13). 수용부의골삭제를시행하는경우대게치경부쪽은넓게치근부는좁게형성하는데이러한형태로인해이식치를적합시키는과정에서 Hertiwig s epithelium 또는치근막의손상을줄수있으므로자가치아이식의성공을위해이러한술식도중의외상을줄이는것이중요하며 14) 최근에는술전촬영된 CT을이용하여공여치와이식와의 3차원적인길이, 폭등의수치들을측정하여술식을사전계획할수있다. 뿐만아니라공여치를복제하여만들어진레진치아를실제술식시활용하는 Compu ted Aaided Rapid Prototyping을시행하여구강외의노출시간을줄이고술식과정에서발생할수있는외상을최소화하기위한시도를하고있다 15). 자가치아이식의성공은임상및방사선검사를통해서평가할수있다. 임상적으로이식치는정상적인치아의동요도와기능을가져야하며방사선사진상에서는이식치주위로결합조직의발생이보이지않고치조백선이관찰되어야하며진행성의치근흡수가없어야한다 16). 본증례는치근단발육이 3-5mm 또는 3/4정도이루어진이상적인시기에이식이이루어진것을아니지만근단공의폐쇄가완전히이루어지지않은단계에서시행된술식으로치수재생이일어나치수생활력을유지하게되었고치근의외흡수와같은부작용의발생없이정상적인기능을수행하였다. 제 3대구치를이용한자가치아이식은임상에적용하기 에유효한술식이며치근단이완성된경우보다치근단이미완성된경우에서더나은결과를기대할수있다. Lundberg등은자가치아이식술에서치근단이완성된경우 84%, 치근단이미완성된경우에서 94% 로그성공률을보고하였다 11). 새로운수용부를형성할필요없이수용부에바로치아이식을시행할수있는경우라면발치와와치근모두에치근막세포가존재하며이식와에서혈류공급이보다양호하므로 17) 더좋은예후를기대할수있을것으로생각된다. 자가치아이식의성공을위해서는술식후의주기적인관리가중요하다. 자가치아이식을시행한후치은부착의생성에는약 1주일이소요되는데이기간동안에는환자가스스로 brushing을하는데어려움이있으므로 1-2일간격으로내원하도록하여치은연상의치태를제거한다. 치아고정은치근막이치유되는약 3주까지유지한뒤고정장치를제거한다. 치수괴사는술후 8주동안약 80% 에서진단이가능하고 6개월후에는확정지을수있으므로술후 6개월까지는매월임상및방사선검사를시행한다. 이후에도환자를정기적으로내원하도록하여치태관리및경과관찰이필요하다 18). Ⅳ. 요약자가치아이식은다른술식에비해보존적, 경제적이며빠르게시행할수있다는장점을가진다. 자가치아이식의성공을위해서적절한공여치의선택하여술식과정중에서공여치의구강외노출시간을줄이고치근막의손상을최소로하는외과적술식을시행해야한다. 또한시술후에적절한치태관리및정기적검사를시행하는것이중요할것으로사료된다. REFERENCES 1. Kim HC. Color atlas of autotransplantation 이론과임상. 지성출판사. 1997. 2. Hernandez SL, Cuestas-Carnero R. Autogenic

치아결손부에자가치아이식술을시행한치험례 27 Tooth Transplantation: A report of ten cases. J Oral Maxillofac Surg 1988;46:1051-1055. 3. Guerini V. A History of Dentistry from the Most Ancient Times Until the End of the Eighteenth Century. Philadelphia: Lea & Febiger, 1909:191-192. 4. Apfel H. Preliminary work in trasplanting the third molar to the first molar position. J Am Dent Assoc 1954;48:143. 5. Fong CC. Transplantation of the third molar. Oral Surg 1953;6:917. 6. Hale ML. Autogenous transplants. J Am Dent Assoc 49: 193. 1954. 7. Clark HB, Tam JC, Mtchell DF. Trans plantation of developing teeth. J Dent Res 1955;34:322. 8. Northway WM, Konigsberg S. Autogenic tooth transplantation. Am J Orghod 1980; 77:146. 9. Kristerson L, Andreasen JO. The effect of splinting upon periodontal and pulpal healing after autotrans plantation of mature and immature permanent incisors in monkeys. Int J Oral Surg 1983;12:239. 10. Apfel H. Autoplasty of enucleated prefunctional third molars. J Oral Surg 1950;9:289. 11. Lundberg T, Isaksson S. A clinical follow-up study of 278 autotransplanted teeth. Br J Oral Maxillofac Surg 1996;34(2):181-5. 12. Skoglund A, Hasselgren G, Tronstad L. Oxido reductase activity in the pulp of replanted and auto transplanted teeth in young dogs. Oral Surg Oral Med Oral Pathol 1978;52:205?209. 13. Andreasen JO. Textbook and Color Atlas of Traumatic Injuries to the Teeth. 4th ed. Blackwell, 2007. 14. Bauss O, Zonios L, Engelke W. Effect of additional surgical procedures on root development of transplanted immature third molars. Int J Oral Maxillofac Surg 2008;37:730-735. 15. Lee SJ, Jung IY, Lee CY et al. Clinical application of Computer Aided rapid prototyping for tooth transplantation. Dent Traumatol 2001;17:114-119. 16. 박병훈, 김우택, 민병진등. 결손치에서의자가치아이식의치험례. 대한구강악안면외과학회지 2002;28: 480-483. 17. Henry JL, Weinmann JP. The pattern of resorption and repair of human cementum. J Am Dent Assoc 1951;42:270-290. 18. Andreasen JO. The effect of splinting upon periodontal healing after replantation of permanent incisors in monkeys. Acta Odontol Scand 1975;33 :313-323.

28 손효정, 장호열, 금윤선, 김현철, 이상철 Management of missing tooth with autotransplantation: A case report Hyo-Jeong Son, Ho-Yeol Jang, Yun-Seon Keum, Hyun-Chull Kim, Sang-Chull Lee Department of Oral and maxillofacial surgery, LivingWell Dental Hospital When missing teeth with the decay or congenital missing teeth are existent, treatments for restoring the function and esthetics of missing teeth include fixed bridge, partial denture, implantation and autotransplantation. There is no absolute indications for each techniques, when there are third molar with approriate form for transplantation, autotransplatation could be applicated. Using the immature tooth shows increased pulp revascularization, decreased pulp necrosis and decreased root resorption compared with fully developed tooth. In this study, we reported a case, hopeless 2nd molar with the decay and apical lesion. Using immature 3rd molar, autotransplantation was carried out. After 4months later, normal conditions were observed without any signs of inflammation. [THE JOURNAL OF THE KOREAN ACADEMY OF IMPLANT DENTISTRY 2009;28(1):24-28] Key words: autotransplantation, pulp healing, periodontal ligament

대한치과이식 ( 임프란트 ) 학회지 2009;28(1):29-40 29 Maxillary sinus floor augmentation and simultaneous implant placement; A retrospective study of 614 dental implants (514 HA-coated Tapered Screw-Vent implants and 100 FBR coated Pitt-Easy implants.) 1 Department of Oraland MaxillofacialSurgery, LivingWellDentalHospital 2 Department of Oraland MaxillofacialRadiology, LivingWellDentalHospital Ho-Yeol Jang 1, Hyoun-Chull Kim 1, Sang-Chull Lee 1, Jang-Yeol Lee 2 I ntroduction Alveolar bone resorption and pneumatization of the maxillary sinus after the extraction of teeth limit the quantity and quality of the bone necessary for successful implant placement, especially in the edentulous posterior maxilla 1). Many authors who have managed the insufficient bone problem in the posterior maxilla have reported various maxillary sinus floor augmentation techniques to increase bone volume and height. The sinus elevation surgery for implant placement was initially introduced by Boyne and James 2) and by Tatum 3). In these reports, the sinus was exposed by a modified Caldwell-Luc operation. The grafts were placed on the bony cavity prior to the implant placement. Since these early reports, several modifications for the sinus floor elevation have been made to the surgical technique and in the materials used. A less invasive technique for the sinus floor elevation with grafting and simultaneous implant placement was introduced by Summers 4). It was described that the pressure from the shaved bone, the added graft materials, and the trapped fluids caused a dome shaped elevation of the sinus floor as the osteotomes were inserted. Currently, various internal sinus floor elevation techniques used to access the sinus Corresponding author : Ho -Yeol Jang Department of OMFS, LivingWell dental hospital, 110, Juyeop-Dong, Ilsan-Seo-Gu, Koyang-city, 411-370, Gyeonggi-do, Korea E-mail : jhy5102@hanmail.net Received March 6, 2009 Revised May 25, 2009 Accepted June 17, 2009 cavity have also been developed by many authors; such as the crestal core elevation, 5) the localized management of the sinus floor, 6) the antral membrane balloon elevation, 7) the hydraulic sinus condensing technique, 8) on-site sinus compaction, 9) and utilizing sinus drill technique 10). These techniques are simple and less invasive compared to the lateral approach techniques In the simultaneous implant placement, the maxillary sinus is augmented and dental implants are placed into the grafted site at the same time. This technique offers the advantages of less surgical treatment for the patient and a coordinated consolidation of the graft around the implants during healing period, thus reducing both the surgical and healing times for the patient 11). In our hospital, sinus floor augmentations were performed with 3 different surgical techniques and accomplished the bone grafting and the simultaneous placement of the Hydroxyapatite (HA) coated and the Fast Bone Regeneration (FBR) coated implants. The aim of this retrospective study was to evaluate the clinical significance and the survival rates of our techniques. Materials and Methods 1. Patients A total of 614 dental implants were placed into 419 grafted maxillary sinuses in 354 patients during a 6-year period (2003 through 2008). The patient population consisted of 224 males and 130 females ranging in age from 16 to 81 years (mean age 48.9 years) (Table 1). All patients were taken the cone beam computerized tomography (CBCT, i-cattm, ISI, USA) to analysis the physiology condition and the bone volume of the

30 HY Jang, HC Kim, SC Lee, JY Lee maxillary sinus. Patients were excluded if they exhibited pathological findings or had a history of maxillary sinus diseases or operations. 2. Graft materials 3 different types of grafts were used; the autogenous bone, allograft (Tutodent, Tutogen, Germany) and alloplast (Cerasorb, Curasan, Germany). The auto genous bone was harvested from the mandibular ramus or the iliac crest. The grafts were used alone or combination with the other grafts. 3. Implant Types 2different implant systems were used; the hydroxy apatite (HA) coated implants (Tapered Screw-Vent, Zimmer, USA) (Fig. 1) and the FBR (Fast Bone Regeneration) coated implants (Pitt-Easy, Oraltronics, Germany) (Fig. 2). Regardless of alveolar bone height prior to the grafting, all implants (514 TSV and 100 Pitt-Easy) were placed into the grafted sinuses simultaneously. 4. Surgical procedures The sinus floor augmentation and the simultaneous Fig. 1. MTX and MP-1 HA Coated surfaced implant ; Tapered Screw-Vent implant (TSV, Zimmer, USA). implant placement were carried out under local anesthesia using 1 of 3 surgical techniques; the lateral approach technique, the osteotome technique and the crestal approach technique utilizing sinus drills. The lateral approach technique was performed using a modified Caldwell Luc procedure described by Kent and Block 12). The full-thickness mucoperiosteal flap was raised to expose the lateral wall of maxillary sinus. After the osteotomy of lateral wall (Fig. 3), the sinus membrane was gently reflected across the sinus floor (Fig. 4). The prepared grafts were inserted into the elevated sinus (Fig. 5). The implants were placed simultaneously (Fig. 6) and the grafts were condensed around the implant body through the lateral window. After filling of the bony cavity completely, the bony window was repositioned to its original position. The osteotome technique was performed by a crestal approach. It was reflected in a full-thickness mucoperiosteal flap to expose the crestal part of the alveolar ridge. After preparing the implant site with implant drills to 2 mm beneath the sinus floor, the osteotomes were inserted to expand the preparation area both horizontally and vertically (Fig. 7). Osteotomes in increasing diameters were used to create a site for implant placement and elevate the sinus floor (Fig. 8). Grafts were incrementally placed and packed into the prepared sites by osteotomes. The implants were placed simultaneously in the surgical sites. The utilizing sinus drill technique was performed in combination with the osteotome technique. It was reflected in the full-thickness mucoperiosteal flap to expose the crestal part of alveolar ridge, similar to osteotome technique. After preparation of the implant site with the implant drills to 1 mm beneath the sinus floor (Fig 9), sinus drills were passed to cut and elevate the cortical bone of sinus floor. Sinus drills and osteotomes in increasing diameters are used to create a Fig. 2. V-TPS with additional FBR surfaced implant ; Pitt-Easy(Oraltronics, Germany). Fig. 3. Osteotomy of lateral wall.

Maxillary Sinus Floor Augmentation and Simultaneous Implant Placement; A retrospective study of 614 dental implants 31 Fig. 4. Reflection of sinus membrane by hand instrument. Fig. 8. Osteotomes in increasing diameters. Fig. 5. Insertion of graft into the elevated sinus. Fig. 9. Prepared implant site with the implant drills. Fig. 6. Implant placement. Fig. 10. Elevation of sinus floor using sinus drill. Fig. 7. Horizontal and vertical expansion by osteotomes. Fig. 11. Incremental placement and condensing of graft into prepared site.

32 HY Jang, HC Kim, SC Lee, JY Lee site for the implant placement and elevate the sinus floor (Fig. 10). Grafts were incrementally placed and condensed into the prepared sites by condensers and osteotomes (Fig. 11). The implants were placed simul taneously in the surgical sites. 5. Prosthetic treatment and follow-up Three to 8 months afterwards, the implants were loaded with single tooth restorations, multiple-unit implantsupported restorations or overdentures. Patients were followed up every 4 months for supportive care and evaluation. The mean observation follow-up period was 34.7 months. Panoramic radiographs were made pre-, post-operative and after 12 months in order to evaluate the peri-implant bone and maxillary sinuses. Table 1. PATIENTS Number of patient(n) 354 Male/female(n) 224/130 Mean age, range(yr) 48.9, 16~81 Total number of grafted sinus(n) 419 Total number of implants(n) 614 (TSV:514 / Pitt-Easy:100) 6. Survival criteria Survival meant that an implant was immobile when manually tested, did not exhibit peri-implant radio lucency, had no irresolvable clinical symptoms or mechanical problems, was clinically intact, and fully met its prosthodontic purpose. All clinically failed implants were removed and were recorded as failures in the database. Patients with failed implants were subsequently treated outside of the study. 7. Statistical Methods The Survival rates for the TSV and the Pitt-Easy implants were analyzed by 7 factors as follows. a. Survival rate associated with loading b. Mean of remaining bone width & height / Survival rate associated with implant sites c. Survival rate according to remaining bone height d. Distribution and survival rate according to graft material f. Implants distribution of sinus floor elevation methods and survival rate e. Survival rate according to implant length h. Survival rate according to implant diameter The survival rates were calculated at 3 points (before loading, after loading and a total period) in each factor. A P-value of 0.05 was considered to be statistically relevant. Results The survival rate associated with loading is seen in Table 2. 14 TSV implants and 3 Pitt-Easy implants were failed during the healing period; the osseo integration rates were 97.3% and 97%, respectively. And 2 TSV implants were failed by prosthetic fracture and all Pitt-Easy implants were survived during functional loading; the survival rates during loading period were 99.6% and 100%, respectively. The TSV and Pitt-Easy implants had the overall survival rates of 96.9% and 97%, respectively. There was no statistically significant difference (P>.05) between these two implant systems. The means of the remaining bone width and height associated with each implant site of posterior maxilla were measured in the pre-operative CT (Table 3). The average pre-operative height of the maxillary alveolar bone was 6.1±3.2 mm (range: 0-12.5 mm); 7.2±3.3 mm at the premolar and 5.8±3.1 mm at the molar regions. The implant survival rates were evaluated in relation to each implant site, the lowest survival rates were showed in the first molar regions. Table 4 summarizes the survival rate of the implants by remaining bone height. Although bone height beneath Table 2. Survival rate associated with loading TSV Pitt-Easy Loading Fail(n) Cause of failure Fail(n) Cause of failure Before loading(bl) 14 Non-osseointegration 500/514(97.3) 3 Non-osseointegration 97/100(97) After loading(al) 2 Prosthetic problem 498/500(99.6) 0 97/97(100) Total 16 498/514(96.9) 0 97/100(97)

Maxillary Sinus Floor Augmentation and Simultaneous Implant Placement; A retrospective study of 614 dental implants 33 Table 3. Mean of remaining bone width & Height / Survival rate associated with implant sites Site Mean of remaining bone Width Height (mm) (mm) Fail(n) TSV Pitt-Easy BL AL Total Fail(n) BL AL Total P1 7.1 8.5 1 30/31(96.8) 30/30(100) 30/31(96.8) 0 12/12(100) 12/12(100) 12/12(100) P2 8 6.7 3 98/101(97) 98/98(100) 98/101(97) 0 21/21(100) 21/21(100) 21/21(100) M1 10.5 5.8 10 215/223(96.4) 213/215(99) 213/223(95.5) 2 36/38(94.7) 36/36(100) 36/38(94.7 M2 10.6 5.7 2 157/159(98.7) 157/157(100) 157/159(98.7) 1 28/29(96.6) 28/28(100) 28/29(96.6) Total 9.9 6.1 16 500/514(97.3) 498/500(99.6) 498/514(96.9) 3 97/100(97) 97/97(100) 97/100(97) Abbreviations: BL, before loading; AL, after loading Table 4. Survival rate according to remaining bone height TSV Pitt-Easy Bone height Fail(n) Fail(n) BL AL Total BL AL Total H 2 3 58/60(96.7) 57/58(98.3) 57/60(95) 0 16/16(100) 16/16(100) 16/16(100) 2<H 5 8 146/153(95.4) 145/146(99.3) 145/153(94.8) 1 20/21(95.2) 20/20(100) 20/21(95.2) 5<H 8 3 154/157(98.1) 154/154(100) 154/157(98.1) 0 24/24(100) 24/24(100) 24/24(100) H>8 2 142/144(96.6) 142/142(100) 142/144(96.6) 2 37/39(94.9) 37/37(100) 37/39(94.9) Total 16 500/514(97.3) 498/500(99.6) 498/514(96.9) 3 97/100(97) 97/97(100) 97/100(97) the sinus was 2 mm or less, all implants were placed simultaneously and the high survival rates of more than 95% were observed in both the TSV and the Pitt-Easy implants. The high survival rates of more than 97% were observed in both the TSV and the Pitt-Easy implants when the autogenous bone was used alone and combi nation with the alloplast in comparing with the other graft materials (Table 5). Table 6 summarizes the survival rate of implants according to surgical methods for sinus floor elevation. The crestal approach technique utilizing sinus drills was showed the highest results (100%) among the three different methods in both the TSV and the Pitt-Easy implants. Table 7 summarizes the survival rate of implants based on implant length. All implant lengths showed survival rates of better than 94%. Table 8 summarizes the survival rate of implants based on implant diameter. All implant diameters showed survival rates of better than 93%. Discussions The posterior maxilla often presents a challenge to implant dentists because of inadequate bone volume from the crest of the bone to the floor of the maxillary sinus. Unpredictable bone loss can occur after tooth extraction, particularly if there is an existing bony defect or radiolucency 13). Early tooth loss often leads to pneumatization of sinuse. The lack of bone in the posterior maxilla is a challenge to clinicians placing dental implants 14). Sinus lifting procedures have significantly expanded the indications and improved the predictability of implant therapy by allowing placement of implants of proper in the posterior maxilla 15). The long term results presented in this article showed that when implants of sufficient length are placed, success can be maintained over the long term, even in areas of poor bone density and/or augmented bone. The sinus augmentation with the grafting and the implant placement are accomplished as either a 1-step

34 HY Jang, HC Kim, SC Lee, JY Lee Table 5. Distribution and survival rate according to graft material Graft materials Fail(n) TSV Pitt-Easy Fail(n) BL AL Total BL AL Total Autogenous bone 3 129/130(99.2) 127/129(98.4) 127/130(97.7) 1 42/43(97.7) 42/42(100) 42/43(97.7) Allograft 2 31/33(93.9) 31/31(100) 31/33(93.9) Alloplast 1 7/8(87.5) 7/7(100) 7/8(87.5) Autogenous+Allograft 1 1/2(50) 1/1(100) 1/2(50) Autogenous+Alloplast 5 252/257(98) 252/252(100) 252/257(100) 1 45/46(97.8) 45/45(100) 45/46(97.8) Autogenous+ Allograft+Alloplast 2 1/3(33.3) 2/2(100) 1/3(33.3) Allograft + Alloplast 1 1/1(100) 1/1(100) 1/1(100) None 2 78/80(97.5) 78/78(100) 78/80(97.5) 1 1 0/11(90.9) 10/10(100) 10/11(90.9) Total 16 500/514(97.3) 498/500(99.6) 498/514(96.9) 3 97/100(97) 97/97(100) 97/100(97) Table 6. Implants distribution of sinus floor elevation methods and survival rate Surgical Methods Fail(n) TSV Pitt-Easy Fail(n) BL AL Total BL AL Total OSFE 10 254/264(96.2) 254/254(100) 254/264(96.2) 3 53/56(94.6) 53/53(100) 53/56(94.6) Lateral window 6 234/238(98.3) 232/234(99.1) 232/238(97.4) 0 38/38(100) 38/38(100) 38/38(100) Utilizing Sinus drill 0 12/12(100) 12/12(100) 12/12(100) 0 6/6(100) 6/6(100) 6/6(100) Total 16 500/514(97.3) 498/500(99.6) 498/514(96.9) 3 97/100(97) 97/97(100) 97/100(97) or a 2-step surgical procedure 16-19). In the 1-step procedure, the maxillary sinus is augmented and dental implants are placed simultaneously into the grafted site. In the 2-step procedure, implant placement is delayed until there is evidence that the graft material has provided adequate bone in the posterior maxilla. The 1- step procedure offers the advantages of less surgical treatment for the patient and a coordinated consoli dation of the graft around the implants during healing period, thus reducing both the surgical and healing times for the patient. The general consensus, based on empirical observations, has been that the 1-step procedure should be reserved for patients who have at least 5 mm of alveolar bone in the posterior maxilla to stabilize the implants 20,21). If there is less than 5 mm of available host bone, it has been considered insufficient to mechanically maintain the implants, and thus the 2- step procedure has been recommended in these patients 21-23). In the present study, however, regardless of alveolar bone height (range: 0-12.5 mm) prior to the grafting, all implants were placed into the grafted sinuses simultaneously, and the primary stabilization of implants were presented in all cases. The results were showed that the high survival rates of more than 95% were observed in both the TSV and the Pitt-Easy implants, although remaining bone height beneath the sinus was 2 mm or less (Table 4). The grafting materials can be categorized into four groups; autografts, demineralized or mineralized allografts, xenografts and alloplasts. Ideal grafting materials should meet a number of requirements: osteogenetic (stimulate surviving osteoblasts to form new bone), osteoconductive (serve as a scaffold for the ingrowth of vessels from neighboring bone), and osteoinductive (make pluripotential mesenchymal cells differentiate into osteoblasts) effect 24). Autogenous grafts meet all of these requirements and have therefore been defined as the gold standard

Maxillary Sinus Floor Augmentation and Simultaneous Implant Placement; A retrospective study of 614 dental implants 35 Table 7. Survival rate according to implant length TSV Pitt-Easy Length(mm) Fail(n) Fail(n) BL AL Total BL AL Total 10 0 5/5(100) 5/5(100) 5/5(100) 11.5 0 3/3(100) 3/3(100) 3/3(100) 12 1 62/63(98.4) 62/62(100) 62/63(98.4) 13 16 483/497(97.2) 481/483(99.6) 481/497(96.8) 14 2 35/37(94.6) 35/35(100) 35/37(94.6) 16 0 9/9(100) 9/9(100) 9/9(100) Total 16 500/514(97.3) 498/500(99.6) 498/514(96.9) 3 97/100(97) 97/97(100) 97/100(97) Table 8. Survival rate according to implant diameter TSV Pitt-Easy Diameter Fail(n) Fail(n) BL AL Total BL AL Total 3.25 0 5/5(100) 5/5(100) 5/5(100) 3.7 7 193/198(97.5) 191/193(99) 191/198(96.5) 3.75 0 18/18(100) 18/18(100) 18/18(100) 4 1 46/47(97.9) 46/46(100) 46/47(97.9) 4.1 0 10/10(100) 10/10(100) 10/10(100) 4.7 8 282/290(97.2) 282/282(100) 282/290(97.2) 4.9 2 28/30(93.3) 28/28(100) 28/30(93.3) 6 1 15/16(93.8) 15/15(100) 15/16(93.8) Total 16 500/514(97.3) 498/500(99.6) 498/514(96.9) 3 97/100(97) 97/97(100) 97/100(97) among grafting materials. Common donor sites are the mandible, the iliac crest, and the skull 25,26). Autogenous grafts provide an excellent source of cells, growth factors, and bone morphogenic proteins with no risk of antigenicity or crossinfection. The disadvantages of autogenous grafts include hospitalization (extraoral) or require a second surgical site (intraoral), which increases the length of time of the surgery, the surgical risk, and the morbidity of the procedure 27). Allografts can be cortical or trabecular and are harvested from human cadavers. They are available in a freeze-dried form, eliminating the risk of crossinfection by the processing and sterilization methods. Allografts can be mineralized or demineralized. Both forms have osteoconductive properties and can serve as a scaffold that promotes the growth of new bone. Osteoinductive ability of DFDBA is questionable yet 28,29). Xenografts, particularly bovine-derived bone, act as a resorbable osteoconductive material in the augmented sinus 30). Osteoconductive properties of the xenografts may be documented by close contact between the grafts and newly formed bone 31,32). As xenografts have a relatively long resorption time, the graft particles are still present after 4 years in the present human specimens 33). Alloplast is the mineral or inorganic component of bone such as β-tricalcium phosphate, coral hydroxyapatite, or bioactive glasses. Hydroxyapatite is nonresorbable and acts as a scaffold for osteoconduction. In contrast, β- TCP is almost resorbed completely and replaced with

36 HY Jang, HC Kim, SC Lee, JY Lee new bone 34-38). Although the alloplast lacks growth factors, it does have osteoconductive properties. Because donor sites generally provide only a limited amount of grafts, autogenous bone is often mixed with other grafting materials (allograft, xenograft, or alloplast). The proportion of autogenous bone and other grafting materials is mainly dependent on the available quantity of autogenous bone. A higher proportion of autogenous bone improves osteogenic potential in the graft mixture. However, the ideal proportion of autogenous bone and other grafting materials is yet to be determined 26,27). During sinus grafting, these materials are combined with autografts, accommodated in the sinus cavity, and adapted against the floor of the sinus 39,40). In the results of this study, the high survival rates of more than 97% were observed in both the TSV and the Pitt-Easy implants when the autogenous bone was used alone and combination with the alloplast comparing with the other graft materials (Table 5). Early reports 41-46) in the dental literature documented that the Hydroxyapatite-coated (HA) coating is osteoconduc tive and enhances bone healing at the gaps between the bone and implant surface in comparison to machined and grit-blasted titanium surfaces. Because of the osteoconductive nature of the HA coating, simultaneous bone grafting and implant placement are possible. Numerous short-term 47-50) (<5 years) and long-term 51-59) (5 years and longer) studies have reported clinical success rates ranging from 93.4% to 100% and 93.2% to 99%, respectively, with no significant adverse events attributed to implant surface. Despite these and other widely documented findings on the clinical effectiveness of HA-coated implants, several case reports 60-62) during the early 1990s suggested that HA coatings were inherently unstable, susceptible to dissolution in the presence of bacterial infection, and possibly predisposed to rapid bone loss or saucerization around the cervical end of the implant. Such findings have not been substantiated by long-term clinical studies, nor do they reflect the current state of HAcoated implant technology 61,62). Research conducted over the past decade has documented that highly crystalline HA implant coatings exhibited greater resistance to dissolution and higher percentages of bone-to-implant contact in comparison to HA coatings with lower crystallinity 63-67). Kay 65) stated that the percentage of the crystalline phase in HA coatings should be maximized to contain no less than 90% crystalline HA. Burgess et al 66,67) reported on a novel, pressurized, hydrothermal and, post-plasma spray process, called MP-1 (Zimmer, USA), that has been documented to convert the crystalline non-ha and amorphous components of plasma-sprayed HA coating back into crystalline HA. The resulting study about coating was found to contain more than 90% crystalline HA 66,67). Compared with the untreated control coating, the MP-1-treated surface exhibited equivalent adhesive strength to the implant surface but significantly decreased in vitro solubility over a wide range of ph levels 66,67). The FBR (Fast Bone Regeneration) coated Pitt-easy implant surface obtained by vacuum titanium plasma and electrochemical deposition of a thin layer (15-20μ m) of a fully resorbable 100% calcium phosphate (Ca/P:1). The compatibility of titanium implants with bone can be improved by means of calcium phosphate coatings, because they prevent the fibrous tissue encapsulation and enable the direct apposition of bone to the implants. CaP-coatings on implants are therefore only required for the time of osteointegration of the implants 68). Their structure has to offer the matrix and their dissolution properties have to support the conditions for an early immobilization of osteoblast like cells and for the development of vascularized bone tissue on the implants as well as in the gap between implant surface and natural bone. Finally the CaPcoatings have to be resorbed and replaced by new bone tissue. The FBR coating shows remarkable blood capillary effect for an intensive and premature anchorage, and achieves a 23% higher rate of bone deposit than with other, rough-structured surfaces after 6 weeks of implant placement 69). So the FBR implant can perform an early loading after 6 weeks, and especially effective in bone quality D3 and D4 with severely spongeous cancellous bone or in substance with rich bone marrow. The implant surface texture in augmented sinus areas seems to play an important role in overall survival rates. This study indicates that the sinus floor augmentation to accomplish autogenous bone grafting and simultaneous placement of HA-coated or FBR surface implant has the potential for long-term success. Conclusions The simultaneous implant placement into the maxillary sinus grafted with the autogenous bone is a clinically predicable and acceptable method. In this study, the

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