Poster Thumbnail
Marginal bone change and implant survival following vertical guided bone regeneration, A retrospective analysis

Joseph Kan, DDS, MS

Sunee Limmeechokchai, DDS – Resident, Loma Linda Univeristy

Sasiya Bhumpattarachai, DDS – Resident, Loma Linda Univeristy

Kenzo Shiozaki, DDS – Resident, Loma Linda Univeristy

Samuel Sauza, DDS – Resident, Loma linda university

Kittichai Rungcharassaeng, DDS, MS

Jaime Lozada, DMD – Professor and Director, Loma Linda Implant department

Purpose of the Study: The purpose of this retrospective study is to investigate and assess marginal bone loss and survival rate of implants placed following vertical bone augmentation.

Methods: This study will be conducted in the Center for Implant Dentistry, Loma Linda University, California, United States. The treatment records, periapical radiographs, panoramic radiographs, and/or cone beam computed tomography (CBCT) of patients who received implants following vertical bone augmentation between 2007-2019 will be retrospectively reviewed and selected. Total 200 implants will be reviewed by four calibrated examiners and following parameters will be collected: 1) Patient demography (age and gender) 2) Patient with the history of diabetes and smoking 3) Date of vertical guided bone regeneration surgery 4) Type of bone graft 5) Type of barrier membrane 6) Name of a surgeon who performed guided bone regeneration surgery and implant placement 7) Complication after guided bone regeneration surgery and implant placement 8) Implant placement date 9) Implant site, system, diameter, length 10) Time of final prosthetic loading 11) Type of final prosthesis 12) Type of opposing dentition 13) Number of implant removal 14) Percentage of marginal bone loss Data collection: The measurements of marginal bone level will be digitally performed. The remodeling of the crestal bone will be monitored using calibrated periapical radiographs, panoramic radiographs and/or cone beam computed tomography (CBCT) taken immediately after implant placement compare to the latest follow up radiographs. Bone change is the distance between the implant platform and first bone-to-implant contact . Marginal bone loss will be calculated in percentage. The analysis of implants survival rate associated with each recorded parameter will be performed by descriptive analysis

Results: Results will be presented on e-poster.

Conclusion: Conclusion will be presented on e-poster

Articles: 1. Rocchietta I, Fontana F, Simion M. Clinical outcomes of vertical bone augmentation to enable dental implant placement: a systematic review. J Clin Periodontol 2008 Sep;35(8 Suppl):203-15. 2. Mecall RA, Rosenfeld AL. Influence of residual ridge resorption patterns on implant fixture placement and tooth position. 1. Int J Periodontics Restorative Dent 1991;11(1):8-23. 3. Buser D, Ingimarsson S, Dula K, Lussi A, Hirt HP, Belser UC. Long-term stability of osseointegrated implants in augmented bone: a 5-year prospective study in partially edentulous patients. Int J Periodont Restor Dent 2002;22(2):109–17. 4. Chiapasco M, Zaniboni M, Boisco M. Aug- mentation procedures for the rehabilitation of deficient edentulous ridges with oral implants. Clin Oral Implants Res 2006;17(Suppl 2):136–59. 5. Urban IA, Jovanovic SA, Lozada JL. Vertical ridge augmentation using guided bone regeneration (GBR) in three clinical scenarios prior to implant placement: a retrospective study of 35 patients 12 to 72 months after loading. Int J Oral Maxillofac Implants 2009 May-Jun;24(3):502-10. 6. Urban IA, Lozada JL, Jovanovic SA, Nagursky H, Vertical ridge augmentation with titanium-reinforced, dense-PTFE membranes and a combination of particulated autogenous bone and anorganic bovine bone-derived mineral: a prospective case series in 19 patients. Int J Oral Maxillofac Implants 2014 Jan-Feb;29(1):185-93. 7. Donos N, Mardas N, Chadha V. Clinical outcomes of implants following lateral bone augmentation: systematic assessment of available options (barrier membranes, bone grafts, split osteotomy). J Clin Periodontol 2008;35(8 (Suppl)):173–202. 8. Clementini M, Morlupi A, Canullo L, Agrestini C, Barlattani A. Success rate of dental implants inserted in horizontal and vertical guided bone regenerated areas: a systematic review. Int J Oral Maxillofac Surg 2012 Jul;41(7):847-52. 9. Aghaloo TL, Moy PK. Which hard tissue augmentation techniques are the most successful in furnishing bony support for implant placement?. Int J Oral Maxillofac Implants 2007;22 Suppl:49-70. 10. Tonetti MS, Hämmerle CH. Advances in bone augmentation to enable dental implant placement: Consensus Report of the Sixth European Workshop on Periodontology. J Clin Periodontol 2008 Sep;35(8 Suppl):168-72.

  View Poster
Poster Thumbnail
3D Bio-Printed Scaffold for Bone Augmentation

Blake Adams, DDS – Resident, Loma Linda University

Sam Souza, DDS – Resident, Loma Linda University

Purpose of the Study: Evaluate the ability of 3D bio-printed PCL scaffolds to allow bone formation within the created defects and access the accuracy of these printed scaffolds within the created defects.

Methods: A total of 5 New Zealand white rabbits were used for this study. One rabbit was used to calibrate and test the surgical procedure prior to the involvement of the remaining 4 rabbits. Using cone beam computed tomography (CBCT) a defect was digitally created and a surgical guide fabricated to ensure all defects were the same in the right and left tibia. A PCL scaffold was then designed anad 3D bio-printed to fill the defect for augmentation. Each animal was then sedated under general anesthesia and surgical exposure of both tibia's was performed. Two identical defects were then created with the use of the surgical guide. The defect on the right tibia served as the control in this study with the tibia on the left as the test site. Bio-printed PCL scaffolds were then placed in the defects and stabilized within the left tibia with two titanium screws. On the control (right) side, a mixture of autogenous bone and xenograft were placed in the defect and covered with a resorbable membrane and secured with 4 tacks. The grafted sites were closed and allowed to heal for 16 weeks prior to euthanasia for resection of both the test and control bones for microCT and histologic analysis.

Results: Results will be presented at the meeting

Conclusion: Conclusion will be presented at the meeting

Articles: 1. Fahmy MD, Jazayeri HE, Razavi M, Masri R, Tayebi L. Three‐Dimensional Bioprinting Materials with Potential Application in Preprosthetic Surgery. Journal of Prosthodontics. 2016 Feb 1. 2. Green DW, Lee JS, Jung HS. Small-Scale Fabrication of Biomimetic Structures for Periodontal Regeneration. Frontiers in physiology. 2016;7 3. Barabaschi GD, Manoharan V, Li Q, Bertassoni LE. Engineering pre-vascularized scaffolds for bone regeneration. InEngineering Mineralized and Load Bearing Tissues 2015 (pp. 79-94). Springer International Publishing. 4. Dodziuk H. Applications of 3D printing in healthcare. Kardiochirurgia i Torakochirurgia Polska. 2016 Sep;13(3):283-93. 5. Ferreira JN, Rungarunlert S, Urkasemsin G, Adine C, Souza GR. Three-Dimensional Bioprinting Nanotechnologies towards Clinical Application of Stem Cells and Their Secretome in Salivary Gland Regeneration. Stem Cells International. 2016 Dec 20;2016 6. Hung BP, Naved BA, Nyberg EL, Dias M, Holmes CA, Elisseeff JH, Dorafshar AH, Grayson WL. Three-dimensional printing of bone extracellular matrix for craniofacial regeneration. ACS biomaterials science & engineering. 2016 May 2;2(10):1806-16.

  View Poster
Poster Thumbnail
Accuracy and Precision of Implant Placement on Kennedy Class 1 Maxillary models: An in vitro comparison between static guides and use of a dynamic navigation system.

Hung-Chi Liao, DDS – Resident, Loma Linda University School of Dentistry

Purpose of the Study: Computer-aided guide surgery has been widely applied in implant dentistry. Despite the satisfactory result, challenges remain as related to mucosa support. Studies have shown inferior accuracy when using such guides for complete mouth edentulous ridges. Clinically, mucosa-tooth supported guides are used frequently. However, there is a lack of research related to accuracy when using tooth-mucosa supported guides. Therefore, the purpose of this study was to compare the accuracy and precision of mucosa-tooth supported stereolithographic surgical guides with a dynamic navigation system and to determine which method presents more favorable result in Kennedy class I clinical scenario.

Methods: 10 custom made drillable models with a tissue-like coating were designed and fabricated based on a Maxillary Kennedy Class I clinical scenario (with only teeth #6 to #11 present). In this cast, implant #12 has been placed and will be used as a reference. One experienced clinician (>100 implants placed) was randomly assigned to place implants in the positions of teeth #3,5,14 using a stereolithographic surgical guide and also place these implants using a navigator (5 models each). Preoperative CBCT scans were taken on 5 models and used to for guide surgery preparation (NobelClinician). The other 5 models were scanned with fiducial markers and planned in dynamic navigation system. Postoperative CBCT were taken on all of the models. Pre-existing #12 implant was used as a reference for parallelism comparison with #14. Accuracy and precision analysis of #3 and #5 were performed by superimposing the preoperative virtual plan with postoperative CBCT scans. Deviations of placed and planned implant were quantified by using a mathematical algorithm.

Results: TBD.

Conclusion: TBD.

Articles: 1. 2. 3.

  View Poster
Poster Thumbnail
Accuracy of 3D printed models created by two technologies of printers with different designs of model base.

Kenzo Shiozaki, DDS – Resident, Loma Linda Univeristy

Oraphan Rungrojwittayakul, DDS

Charles Goodacre, DDS, MSD

Brian Goodacre, DDS, MSD

Rajesh Swamidass, DDS, MSD

Jaime Lozada, DMD – Professor and Director, Loma Linda Implant department

Purpose of the Study: To evaluate the accuracy of three-dimensional (3D) printed models manufactured using two different printer technologies with different model base designs.

Methods: A Columbia maxillary typodont was scanned using a desktop scanner to generate the Standard Tessellation Language (STL) file as a control group. After the scanning procedure, the STL file was exported to Model Builder for designing the following 2 types of the model bases; 1.) solid base design; and 2.) hollow base design with a 2.0 millimeter thickness of the external shell. Each design was printed to produce 10 models using a Continuous Liquid Interface Production (CLIP) printer and a Digital Light Processing (DLP) printer. The following 4 groups were tested: 1.) CLIP with solid base (CS); 2.) CLIP with hollow base (CH); 3.) DLP with solid base (DS); and 4.) DLP with hollow base (DH). A total of 40 models were scanned using the same desktop scanner to generate the STL files for evaluation of the accuracy. All STL files were superimposed with the control STL file via surface matching software and a comparison was preformed using the 3D color mapping function and a 2D comparison of 48 points selected on the tested model. The data was collected by measuring the deviation between the tested model and the control group. The Kolmogorov-Smirnov test was used for normality distribution testing. Then, Kruskal-Wallis analysis was conducted to assess the overall statistical significance of differences among the tested groups (=.05)

Results: The median values for the deviated distance of the 4 tested group were 0.045 mm. (CH), 0.035 mm. (CS), 0.077 mm. (DH)and 0.077 mm. (DS). There were no statistically significant differences between the accuracy of the 2 groups when using the same printers regardless of the designs of model base (P>.05). However, when comparing the 2 printers using the same model base design and the two different designs of model base, there were statistically significant differences in accuracy (P < .05). The 3D printed models created using CLIP technology had higher accuracy than the DLP technology printer.

Conclusion: The accuracy of 3D printed models was affected by the printer technology regardless of whether the model base was solid or hollow. The CLIP technology printer produced significantly less variation from the reference model than the DLP printer. However, all of the 3D printed models were determined to exhibit a clinically acceptable level of accuracy based on the recorded dimensions being less than 100 micrometers different than the reference model.

Articles: Jin SJ, Kim DY, Kim JH, et al: Accuracy of Dental Replica Models Using Photopolymer Materials in Addictive Manufacturing: In Vitro Three-Dimensional Evaluation. J Prosthodont 2018; Jul2:1-6.18. Camardella LT, de Vasconcellos Vilella O, Breuning H: Accuracy of printed dental models made with 2 prototype technologies and different designs of model bases. Am J Orthod Dentofacial Orthop 2017;151(6):1178-1187.

  View Poster
Poster Thumbnail
Accuracy of implant osteotomy depth and membrane perforation analysis of an in vitro of crestal sinus lift procedure, comparing dynamic navigation system and static guides.

Hung-Chi Liao, DDS – Resident, Loma Linda University School of Dentistry

Purpose of the Study: Crestal sinus lift approach is widely used in implant dentistry when inadequate bone is presented while no lateral approach is needed. However, crestal sinus lift is a blind procedure, in order to drill closer to the sinus floor without perforating the sinus floor, multiple times of periapical x rays are required to confirm it. Therefore, the purpose of this study was to use dynamic navigation system in crestal sinus lift bypass taking periapical x rays and compared with usage of static surgical guide and periapical x ray.

Methods: 10 identical maxillary custom made drillable models with bilaterial sinus cavities and artificial membranes were fabricated. Only #3 and # 14 are edentulous sites, the distance from the crest ridge of #3 and #14 to the sinus floor is 6 mm. The characteristic of artificial membrane closely resembles real human being sinus membrane. 20 4.3 mm x 10 mm Nobel Replace Conical Connection dummy implants (Nobel Biocare®, Yorba Linda, CA, USA) were used in the study. Presurgical CBCT scans were taken on all the models with fiducial markers for static guided and dynamic navigation planning. 5 operators with various implant clinical experience were randomly assigned to place implant in one side by using static surgical guide and confirmed with periapical x rays during the procedure while the other side’s implant was placed using dynamic navigation system by the same operator. Each operator was required to place 4 implants in 2 models. Once the final drill closed to 1 mm from the sinus floor, osteotome instruments and mallet were used to lift the sinus floor up to 4 mm. In conventional procedure side, implant was delivered by hand wrench while in dynamic navigation side, implant was delivered by looking the dynamic navigation system screen. Postsurgical CBCT scans were taken for these 10 models after the implant delivery. Accuracy analysis was performed by using a mathematical algorithm to measure the deviations between planned and delivered implants. Perforation of membrane was evaluated visually.

Results: TBD

Conclusion: TBD

Articles: 1. 2. 3.

  View Poster
Poster Thumbnail
Achieving ideal position of Immediate Implant in molar region by drilling through interradicular bone in multi rooted teeth

Vikaskumar Patel, BDS, DDS

Anuja Patel, BDS, DDS

Osman Ali Khan, BDS

Purpose of the Study: Immediate Implant placement is becoming more and more popular because of ability to limit surgical procedures in one visit and patient comfort. While immediate implant in anterior region has challenges for achieving ideal esthetic result, posterior immediate implant presents its own surgical challenges like difficulty on osteotomy preparation. Immediate molar implant has several challenges including anatomical landmarks, need of atraumatic extraction and keeping as much as buccal and lingual bone intact. Success of Immediate implant is mainly depends on achieving good initial primary stability. Often after extraction of molar we are left with limited bone availability around socket area. Using interradicular septal bone to our advantage to gain primary stability improves the odds of implant osteointigartion. But preparing osteotomy bed for implant in that septa becomes even more challenging because that septa is not supported by adjusting root anymore. That leads to improper angulation or potentially loosing that septal bone. Here, case is presented to show how we can use that septal bone area for proper implant bed preparation before extracting tooth. Drilling through septal area with keeping roots intact gives septal bone much needed support for initial drills and also leads to better angulation for implant.

Methods: Basic Extraction instruments Surgical burs to section crown from the root Implant drills Bone graft cortical cancellous

Results: By keeping roots intact we improved the initial implant osteotomy preparation. Final outcome was achieved with very high initial stability 50N torque. Desired implant angulation and parallelism was achieved. 6 month evaluation of Implant showed successful implant osteointigration with good bone support.

Conclusion: Following this protocol gives us better chance to stabilize our initial drills in proper position and angel. This will improve chances of Immediate Implant success in molar area. Although this technique has given improved final outcome in our case, carful case selection is advised. Selection of case with enough interseptal bone to begin with is very important.

Articles: Implant stability measurements for implants placed at the time of extraction: a cohort, prospective clinical trial. Becker W, Sennerby L, Bedrossian E, Becker BE, Lucchini JP J Periodontol 2005: 76: 391–397 A systematic review on survival and success rates of implants placed immediately into fresh extraction sockets after at least 1 year. Lang NP, Pun L, Lau KY, Li KY, Wong MC. Clin Oral Implants Res 2012;23(5):9–66. Clinical and esthetic outcomes of implants placed in postextraction sites. Chen ST, Buser D. Int J Oral Maxillofac Implants 2009;24:186–217. Immediate implant placement into extraction sites: surgical and restorative advantages. R. J. Lazzara, International Journal of Periodontics & Restorative Dentistry, vol. 9, no. 5, pp. 332–343, 1989.

  View Poster
Poster Thumbnail
Anatomical Study of Mandibular Canal Branches: New Analysis Method of Their Distribution and Structure

Masachika Takiguchi, DDS – Department of Anatomy, Tokyo Medical University, Tokyo, Japan

Iwao Sato, PhD, Adjunct Professor – Department of Anatomy, Tokyo Medical University, Tokyo, Japan

Yoko Miwa, DDS, PhD – Department of Anatomy, The Nippon Dental University, School of Life Dentistry at Tokyo, Tokyo, Japan

Shinichi Kawata, MS – Department of Anatomy, Tokyo Medical University, Tokyo, Japan

Masahiro Itoh, MD, PhD – Department of Anatomy, Tokyo Medical University, Tokyo, Japan

Purpose of the Study: Damage to the branches bifurcating from the mandibular canal is a possible risk of dental implant treatment. Therefore, many radiological analyses have been performed. However, detailed observation of the side branches where hard and soft tissues are mixed has not been sufficiently performed, and association between the nerves and the vasculature remains unclear. Therefore, in this study, we evaluated the mandibular canal branches using a new multilateral method of cone-beam computed tomography (CBCT) analysis followed by immunohistochemical analysis of the soft tissues contained in the same region to detect the trabeculae, nerves, and vasculature that are useful for dental implant treatment and oral surgery.

Methods: A total of 100 cadavers that were preserved in the Department of Anatomy of Tokyo Medical University (50 cadavers) and in the Department of Anatomy of Nippon Dental University (50 cadavers) were used in this study. CBCT images were obtained from the heads of the cadavers and analyzed on an image analysis software. An immunohistochemical analysis of the mandibular canal branches was also performed. This study was a collaborative investigation between both universities.

Results: The new multilateral evaluation method of the mandibular canal branches using CBCT analysis revealed a significant difference between the dentulous and edentulous samples in mainly the anterior regions of the mandibular canal, where branches contained nerves and blood vessels (P < 0.01).

Conclusion: In addition to conventional examinations and diagnoses, this new multilateral assessment method would be effective in avoiding medical malpractice with patients and maximizing the benefits of functional recovery through treatment effects. This new analysis method in this study for distribution and structure of the mandibular branches is expected to provide safer implant treatment in the future.

Articles: 1. Apostolakis D, Brown JE. The dimensions of the mandibular incisive canal and its spatial relationship to various anatomical landmarks of the mandible: A study using cone beam computed tomography. Int J Oral Maxillofac Implants. 2013; 28: 117-124. 2. von Arx T, Hänni A, Sendi P, Buser D, Bornstein MM. Radiographic study of the mandibular retromolar canal: an anatomic structure with clinical importance. J Endod. 2011;37:1630-1635. 3. de Castro MAA, Barra SG, Vich MOL, Abreu MHG, Mesquita RA. Mandibular canal branching assessed with cone beam computed tomography. Radiol Med. 2018; 123: 601-608.

  View Poster
Poster Thumbnail
Autogenous Bone Block graft from Mandibular symphysis used for Augmentation of Alveolar ridge defect due to Facial Trauma: a Case report

Swati Bharadwaj, BDS, MDS – MDS- Oral and Maxillofacial Surgery

Uday Londhe, BDS, MDS – MDS- Oral and Maxillofacial Surgery

Purpose of the Study: The increased awareness of dental implants, has created more and more patients presenting to dental practitioners requesting for fixed teeth replacement solutions to their dilemmas. But for patients with dentoalveolar trauma, rehabilitation becomes difficult, especially when involving front teeth. Facial fracture with tooth avulsion is a complex injury that affects multiple tissues, and very few treatment options offer stable and long-term outcomes.

Methods: Here we report a case of reconstruction of anterior alveolar ridge defect in a 28 years old male after he suffered a Unilateral Lefort I fracture in a road traffic accident. The patient was operated for Open reduction and internal fixation under General Anesthesia. The fractured maxillary segment was fixed by miniplates and screws followed by removal of the avulsed 21, 22 and 23 teeth and associated fractured comminuted bone fragments. After an adequate healing period, an autogenous bone block was harvested from the chin, to augment bone for subsequent prosthetic rehabilitation of the missing 21,22 and 23 teeth alveolar region with an osseointegrated implant. After 6-months, two dental implants were placed w.r.t 21 and 23 region followed by a delayed screw-retained implant supported metal-ceramic prosthesis (FP3) fabrication.

Results: The prosthetic rehabilitation was successful, and after a follow-up period of 2 years, the achieved result was stable.

Conclusion: When the morphology of the bone does not allow proper placement, there are various bone augmentation procedures which aids in reconstruction of the residual alveolar ridge. In cases of bone defects due to fracture, mandibular symphysis can act as a safe, effective and an excellent source of autogenous bone for augmentation allowing a subsequent placement of a dental implant supporting a prosthetic restoration.

Articles: 1. K Harshakumar, Neenu Mary Varghese, R Ravichandran, S. Lylajam. "Alveolar Ridge Augmentation using Autogenous Block Bone Grafts Harvested From Mandibular Ramus to Facilitate Implant Placement: A Case Report". Int J Sci Stud. 2014;2(1):46-50. 2. Kahn A1, Shlomi B, Levy Y, Better H, Chaushu G.The use of autogenous block graft for augmentation of the atrophic alveolar ridge.Refuat Hapeh Vehashinayim. Jul 2003;20(3):54-64, 102.

  View Poster
Poster Thumbnail
Clinical and Radiographical Evaluation of Horizontal Ridge Augmentation Using Composite Grafts and Resorbable Membranes: Case Series

Alper Gültekin, DDS – Research Assistant, Istanbul University

Melike Aytekin, DDS – PhD Student, Istanbul University

Serdar Yalçın, DDS – Full Professor, Istanbul University

Purpose of the Study: Guided bone regeneration procedures allow safe and predictable placement of dental implants in patients lacking sufficient bone volumes. Various materials and techniques for regeneration process are present in the literature, however, there is no golden standard in both materials and techniques nor well-documentation for use of these materials in clinical studies. In this case series, clinical and radiographical outcomes of guided bone regeneration procedure using deproteinized bovine bone (DBB) and particulated autogenous bone mix have been evaluated.

Methods: Under local anesthesia, crestal and vertical incisions were made along the residual alveolar ridge. A mucoperiosteal flap was gently elevated to allow complete visualization of the defect and surrounding bone. Autogenous particulated bone was harvested from nearby the recipient site or ramus using bone scraper (Safe scraper, META, Reggio Emilia, Italy) and mixed with DBB (Cerabone, Botiss Biomaterials GmbH, Berlin, Germany) as a composite graft to be used in lateral ridge augmentation procedures for upper and lower jaws. Grafted bone sites were covered with resorbable membranes (Jason Membrane, Botiss Biomaterials GmbH, Berlin, Germany) in two-stage approach. Resorbable membrane was tacked with pins from palatinal and buccal sites after grafting. Flaps were repositioned with mattress and interrupted non-resorbable sutures with periostal releasing incisions after membranes were completely immobilized with tacks. Patients were allowed to heal 7 months before implant placement. During implant placement, grafted sites were assessed for the necessity of contour grafting. In cases which additional grafting was found necessary, only DBB with resorbable membrane were applied onto the deficient grafted site. The implants were then allowed to acquire secondary stability for the further 3–4 months before prosthodontic rehabilitation. Patients were not allowed to use any removable temporary prosthesis during healing period. Following this period, patients received cement-retained fixed porcelain fused to metal crowns-bridges or removable bar overdenture prosthetic restorations(Figures 1-21). Volumetric changes of grafted sites were measured three-dimensionally using cone beam computed tomography 3 weeks after the augmentation and before implant placement (healing periods were 7 months). The data obtained from the CBCT images were transferred to a network computer workstation, where the volumetric changes of the graft were analyzed using MIMICS 14.0 software (Materialise Europe, World Headquarters, Leuven, Belgium) Other study variables were bone grafting success, and gingival graft requirement.

Results: 13 implants were placed in 7 patients with 10 grafted sites. Only one early membrane exposure was observed as a complication and the case had been excluded from the evaluation process. Clinically, all grafted sites were sufficient for implant stability except two-sites were needed to be re-grafted during implant placement. The average percentage of volume reduction was 6.18±1.53 % before implant placement. A significant graft volume reduction was found during healing period (p < 0.01). Gingivoplasty was performed in two patients. No implants were failed during twenty months follow-up.

Conclusion: Horizontal augmentation with resorbable membranes and composite grafts is a predictable and reliable technique for implant placement. However, clinicians should take precautions with regard to contour augmentation necessity during second stage surgery.

Articles: Urban IA, Lozada JL, Jovanovic SA, Nagy K. Horizontal guided bone regeneration in the posterior maxilla using recombinant human platelet-derived growth factor: a case report. Int J Periodontics Restorative Dent. 2013 Jul-Aug;33(4):421-5 Urban IA, Jovanovic SA, Lozada JL. Vertical ridge augmentation using guided bone regeneration (GBR) in three clinical scenarios prior to implant placement: a retrospective study of 35 patients 12 to 72 months after loading.Int J Oral Maxillofac Implants. 2009 May-Jun;24(3):502-10. Nevins M, Al Hezaimi K, Schupbach P, Karimbux N, Kim DM. Vertical ridge augmentation using an equine bone and collagen block infused with recombinant human platelet-derived growth factor-BB: a randomized single-masked histologic study in non-human primates. J Periodontol. 2012 Jul;83(7):878-84. doi: 10.1902/jop.2012.110478. Epub 2012 Jan 5

  View Poster
Poster Thumbnail
Clinical Application of Autogenous Grinded Tooth Graft in Immediate Implant Placement Procedures: Case Series

Melike Aytekin, DDS – PhD Student, Istanbul University

Alper Gültekin, DDS – Research Assistant, Istanbul University

Serdar Yalçın, DDS – Full Professor, Istanbul University

Purpose of the Study: Alveolar ridge resorption following tooth extraction may considerably affect favorable implant positioning and prosthetic outcomes. Immediate implant placement along with the use of bone grafting materials inside the extraction socket is the most applied treatment protocol to minimize buccal bone collapse and achieve good levels of osseointegration. Variety of bone substitutes are available for grafting procedures, however, there are some concerns regarding these materials’ unpredictable healing patterns, foreing body reactions, inflammation and infection risks and high costs. Extracted and grinded autogenous teeth set an effective alternative with high potential of bone regeneration, less foreign body reaction and cost reduction. The purpose of this case series is to evaluate the effectiveness of autogenous grinded tooth application in immediate implant placement procedures.

Methods: In this case series, seven patients were examined through clinical and radiographical parameters. Patients with hopeless natural teeth showed no restrictions for further surgical  operations. Under local anesthesia, all remaining teeth were extracted, present fillings and decays were removed then teeth were grinded(The Smart Dentin Grinder, KometaBio Inc., New Jersey, USA). Dental implants were placed in the extraction sockets and the gaps between implant and the buccal bone were filled with grinded teeth particulates. Prior to primary closure L-PRF membranes were placed onto the surgical site for an optimal soft tissue healing. Implants were then allowed to acquire secondary stability for the next 3 months before prosthodontic rehabilitation(Figures 1-27). Post-surgical repetitive radiological measurements were performed via Cone Beam Computed Tomography (CBCT) to evaluate volumetric changes in the grafted sites. Images were taken immediately after implant placement, at 3 months after healing and at final follow-up after six months of loading. The data obtained from the CBCT images were transferred to a network computer workstation, where the volumetric changes of the graft were analyzed using MIMICS 14.0 software (Materialise Europe, World Headquarters, Leuven, Belgium) Stabilization of implants, complications during and after surgery, and the presence of any adverse tissue response were also investigated. 

Results: Seven patients were selected to be eligible for inclusion in this study. Totally, 61 sites and implants were evaluated clinically and radiographically. All dental implants were placed in the extracted sites successfully. None of the patients had any surgical complications during the study period. All implants showed satisfactory clinical stability and osseointegration, with a 1-year cumulative survival rate of 100%. All patients experienced uneventful healing without complications associated with the healing of grafted sites. The average percentage of grafted site resorption was found 5.4 ±1.28 % regarding the comparative post-operative CBCT analyses.

Conclusion: The volume of grafted sites were maintained with the autogenous teeth graft material during follow-up. It may be a viable option to fill the buccal gap in immediate implant placement procedures. 

Articles: 1-)Gultekin BA, Cansiz E, Borahan MO. Clinical and 3-Dimensional Radiographic Evaluation of Autogenous Iliac Block Bone Grafting and Guided Bone Regeneration in Patients With Atrophic Maxilla. J Oral Maxillofac Surg. 2016 Nov 26. pii: S0278-2391(16)31186-7. 2-) Pang KM, Um IW, Kim YK, Woo JM, Kim SM, Lee JH. Autogenous demineralized dentin matrix from extracted tooth for the augmentation of alveolar bone defect: a prospective randomized clinical trial in comparison with anorganic bovine bone. Clin Oral Implants Res. 2016 Jun 8. doi: 10.1111/clr.12885.

  View Poster
Poster Thumbnail
Combined Analog and Digital Workflow for an Implant Supported Rehabilitation, Case Report

Saad AlResayes, BDS, MS

Duaij Alazemi, BDS

Aristotelis Marinis, DDS, DMD, MS

Jaime Lozada, DMD – Professor and Director, Loma Linda Implant department

Purpose of the Study: The purpose of this clinical presentation is to illustrate the systematic pretreatment evaluation of an edentulous patient and to demonstrate the integrated analog and digital workflow for the restorative and surgical planning.

Methods: This presentation illustrates the technique of comprehensive implant dentistry planning through integration analog and digital workflow. The technique includes clinical treatment using non-restrictive guided surgery, and the fabrication of a final restoration with Zirconia material. The presentation also showing the procedure of fabricating custom implant abutments utilizing CAD/CAM methods. 48-year-old female patient presented with a chief complaint of: “ My upper denture is not stable and I can’t live with it anymore.” • Diagnosis: • Maxillary complete edentulism • Mandibular partial edentulism • PDI Class IV • Adequate bone quality and restorative space for a maxillary implant-supported full arch fixed zirconia prosthesis and a mandibular segmented fixed zirconia prosthesis.

Results: • Patient was rehabilitated by 4 dental implants in the maxillary arch and 6 dental implants in the mandibular arch. • Surgical procedure was completed utilizing analog and digital workflow by duplicating the dentures and marking the implant position according to the restoratively driven 3D virtual planning on Simplant software (Dentsply Sirona). • Treatment Workflow: - Esthetic Analysis - Diagnostic Wax-Up - Dual Scan / CBCT - Image Merging - 3D Surgical Planning - Provisional Fabrication - Surgical Guide Fabrication - Implant Placement - Prosthesis Conversion - Conventional Implant loading - Final Prosthesis Fabrication

Conclusion: Virtual implant planning and restoratively driven therapy play an important role for optimal success and favorable outcomes. It provides predictable esthetic, functional, and patient dependent treatment from the controlled 3D implant location to final prostheses.

Articles: D'haese J, Ackhurst J, Wismeijer D, De Bruyn H, Tahmaseb A. Current state of the art of computer-guided implant surgery. Periodontol 2000. 2017 Feb;73(1):121-133 Bedrossian E, Sullivan RM, For1n Y, Malo P, Indresano T. Fixed-prosthe1c implant restora1on of the edentulous maxilla: a systema1c pretreatment evalua1on method. J Oral Maxillofac Surg. 2008 Jan;66(1):112-22

  View Poster
Poster Thumbnail
Comparing Implant Telescope and Implant Overdenture for Biological and Hardware Complications: Results of a Long-term Follow-up Investigation

Kazuhiko Inoue, DDS, PhD – Tokyo Medical and Dental University Graduate School

Masanori Nashimoto, DDS, PhD – General Implant Research Center

Yasuki Sekiya, DDS – General Implant Research Center

Yuzo Terayama – Inoue Dental Clinic, Medical Corpolate Yamabukikai

Makoto Shiota, DDS, PhD – Associate Professor, Tokyo Medical and Dental University Graduate School

Purpose of the Study: We investigated a long-term survey on the comparison of the biological and hardware complications with removable prostheses, including implant overdenture and implant telescope (with natural teeth), in full-mouth reconstruction.

Methods: Thirty-three patients of average age 74 ± 9 years (11 males and 22 females; upper: 23 cases and lower: 17 cases) using implant telescope (included Double crown, 40 cases) and implant overdentures (8 cases) were studied from 2001 to 2019 for their clinical follow-up. Biological and hardware complications in 164 implants (Straumann®, Switzerland) and 71 teeth (average denture wearing period: 10 years and 1 month ± 5 years and 2 months) were evaluated statistically.

Results: The survival rates of the implant and natural teeth were 97% and 90%, respectively, indicating no significant difference between them. Hardware complications with implant telescopes (average: 0.8 cases/year) were less than those of implant overdentures (average: 4 cases/year), with a statistically significant difference (P < 0.05). In telescope type of prosthesis, detachment of the inner cap occurred in 23.4% cases, while implant body breakage was recognized only in one case.

Conclusion: Long-term hardware complications with implant telescopes were considerably lesser than that of implant overdentures. It was suggested that implant telescopes recovered the occlusal support over a long period.

Articles: 1. Besimo C, Graber G. A new concept of overdentures with telescope crowns on osseointegrated implants. Int J Periodontics Restorative Dent. 1994; 14: 486−495. 2. Ohkubo C, Kobayashi M, Okamoto N, Hosoi T, Kurtz KS, Murata T. Implant overdenture using Konus telescope on one-piece implant: A case report. Eur J Prosthodont Restor Dent. 2009; 17: 188−191. 3. Kern JS, Kern T, Wolfart S, Heussen N. A systematic review and meta-analysis of removable and fixed implant-supported prostheses in edentulous jaws: Post-loading implant loss. Clin Oral Implants Res. 2016; 27:174−195.

  View Poster
Poster Thumbnail
Comparing the Efficacy of Preventing Submarginal Cement: Chamfer Margin System versus the Reverse Margin System

Emil Svoboda, DDS, PhD, FAAID, DABOI/ID – In Private Practice

Purpose of the Study: This in vitro study compares the use of a custom abutment-crown complex with a chamfer margin connection with that of an inflected margin complex connection called the Reverse Margin. The two systems are compared regarding their ability to prevent submarginal cement.

Methods: A printed acrylic model and milled Chamfer (1) and Reverse Margin (2) zirconia crowns with 80 µ cement space were made to fit complimentary abutments. A simulated gingiva was made from a pink silicone that had been shaped by a custom healing abutment (3) retained by a 5.7 mm implant analogue base (BioHorizons). The abutments were designed to be 1 mm below the silicone gingival margin.(4) Abutment screw access channel was packed with pink Teflon tape and the crowns were cemented into place (RelyX™ Unicem, 3M) while the dental model was on a weigh scale. (5) Crown seating pressure ranged from 38 to 42 NCm. The cement was light cured and the implant analogue-abutment-crown complex was pulled out of the model, disassembled and photographed for analyses. The submarginal cement was made more apparent by rubbing it with blue articulating paper. The process was repeated 10 times for each condition; CM 6 & RM 7

Results: All the chamfer margin cases showed evidence of one or more areas where excess cement had extended beyond the margin of the crown after its cementation. None of the inflected margin cases allowed excess cement to extend beyond the margin.

Conclusion: The Reverse Margin Complex was superior to the Chamfer Margin Complex at preventing submarginal cement. This may have great significance to the long-term safety and stability implant fixed restorations. The Reverse Margin System has been specifically designed to mitigate the two root causes of implant treatment complications identified by the author.

Articles: 1 Korsch M, Obst U, Walther W. Cement‐associated peri‐implantitis: a retrospective clinical observational study of fixed implant‐supported restorations using a methacrylate cement. Volume 25, Issue 7, July 2014, pgs 797-802 2 Wilson TG. The Positive Relationship Between Excess Cement and Peri-implant Disease: A Prospective Clinical Endoscopic Study. J. Periodont 2009;1388-1392 3 Svoboda ELA. Controlling Excess Cement During The Process of Intra-oral Prosthesis Cementation: Overcoming the Gingival Effects. OralHealth Oct 2015;52-66 4 Svoboda ELA. Stock Abutments Cause Problems Preventable by a Well-Designed Prosthesis Installation System. Aug 12, 2019, In Press OralHealth.

  View Poster
Poster Thumbnail
Comparison of Radiographic Visualization of Retromolar Foramina and Canals

Kyoko Fujii, DH – Dent-oral Science Institute

Shigeo Osato, DDS, PhD

Tadakazu Miyao, DDS

Iwao Kuroyama, DDS, PhD

Irika Miyao, DDS

Yukari Osato, DDS

Purpose of the Study: The surgical and anesthetic procedures used for the mandibular molars and retromolar areas may lead to anesthetic failures, injuries, and complications affecting the neurovascular bundles running through the retromolar foramina (RMFs) and the retromolar canals (RMCs). The purpose of this study was to compare the macroscopic photographic findings with those obtained from dental panoramic radiography (DPR) and cone-beam computed tomography (CBCT), in terms of the number, distribution, and dimensions of RMFs in the retromolar areas of the dentate mandibles; the occurrence of RMCs; and the course of RMCs.

Methods: 27 human dried mandibles (54 sides) were evaluated on photographs and radiographic images (2×). The longest diameters of the RMFs were measured using digital vernier calipers. The foramina and canals in the mandibles, in which a wire of 0.25 mm diameter could be inserted at ≥ 2 mm depth, were defined as RMF and RMC, respectively. The DPR and CBCT radiographic images of the mandibles were obtained using a Veraviewepocs 3Df (Morita). The data were statistically analyzed using StatView software.

Results: A total of 61 openings in the retromolar area were observed, but only 14 (22.95%) fulfilled the criteria of RMF. The 14 RMFs were observed in 13 sides (24.07%) involving 11 (40.74%) of 27 mandibles (54 sides). The RMFs were found bilaterally and unilaterally in 2 (18.18%) and 9 (81.82%) mandibles, respectively, with a significant difference (P = 0.0007). There was no significant difference with respect to sides (6 vs. 7) in 27 mandibles. Of the 14 RMFs observed on macroscopic photographs, 5 (35.71%) were large sized (35.71%) and 9 (64.29%) were medium and small sized. The mean length of the long axis of the RMFs was 0.94 ± 0.40 mm (range, 0.50−1.70). DPR detected 3 out of 14 RMFs (21.43%) and 3 out of 14 RMCs (21.43%), and CBCT detected 10 out of 14 RMFs (71.43%) and 10 out of 14 RMCs (71.43%), with significant differences in the distribution (DPR: P = 0.0008 and CBCT: P = 0.0134). The number of RMFs and RMCs detected using CBCT (detected: 10 each and undetected: 4 each) was significantly higher than that detected using DPR (detected: 3 each and undetected: 11 each; P = 0.0107). Three courses of RMCs on the CBCT images were type A (30.00%) and seven were type B (70.00%), with a significant difference (P = 0.0480), according to the classifications of Jamalpour, et al. (2016). The mean angle of inclination between the mandibular canal (MC) and the mandibular plane on the DPR image was 39.00 ± 3.23°, which was significantly larger by 3.41° compared to that in the mandibles without RMCs (P = 0.0245).

Conclusion: These results revealed that CBCT was more useful than DPR to detect RMFs and RMCs in the retromolar areas despite their sizes; however, it was difficult to precisely detect the RMFs of size ≤ 0.9 mm and the corresponding RMCs. It was also suggested that the angles of inclination of the MCs on DPR images, in the mandibles with RMCs as determined by CBCT images, were significantly increased. In clinical practice, particularly when undertaking anesthetic and surgical procedures in the mandibular molar and retromolar areas, RMFs and RMCs, which are not detected by CBCT images, should be taken into careful consideration.

Articles: 1. Moreno Rabie C, Vranckx M, Rusque MI, Deambrosi C, Ockerman A, Politis C, Jacobs R. Anatomical relation of third molars and the retromolar canal. Br J Oral Maxillofac Surg. 2019 Jul 23. doi: 10.1016/j.bjoms.2019.07.006. 2. Kikuta S, Iwanaga J, Nakamura K, Hino K, Nakamura M, Kusukawa J. The retromolar canals and foramina: Radiographic observation and application to oral surgery. Surg Radiol Anat. 2018; 40: 647–652. 3. Truong MK, He P, Adeeb N, Oskouian RJ, Tubbs RS, Iwanaga J. Clinical anatomy and significance of the retromolar foramina and their canals: A literature review. Cureus. 2017; 9: e1781. 4. Park MK, Jung W, Bae JH, Kwak HH. Anatomical and radiographic study of the mandibular retromolar canal. J Dent Sci. 2016; 11: 370–376. 5. Muinelo-Lorenzo J, Suárez-Quintanilla JA, Fernández-Alonso A, Marsillas-Rascado S, Suárez-Cunqueiro MM. Descriptive study of the bifid mandibular canals and retromolar foramina: Cone beam CT vs panoramic radiography. Dentomaxillofac Radiol. 2014; 43: 20140090.

  View Poster
Poster Thumbnail
Comparison on User Convenience and Satisfaction with Two Types of CAD Software for Dental Implant used by Experienced and Untrained Practitioners.

Seong-Min Kim, BChD, DDS – Resident at prosthodontics, Kyungpook National University Dental Hospital

Purpose of the Study: This study aimed to assess the user convenience and satisfaction with two kinds of CAD software used by practitioners who had ever been or not been used CAD software for dental implant.

Methods: Twenty dental technicians who were experienced to use CAD software for dental implant and twelve students who had never been used the CAD software were allowed to design implant custom abutments by using two kinds of CAD software (ExoCad and 3DSystem). They were asked to answer the structured questionnaire (Step 1: Bringing basic information and files, Step 2: Setting the condition before designing abutments, Step 3: Setting abutment design, and Step 4: Overall satisfaction). Mann-Whitney U test was used for statistical analysis for collected data (α = 0.05).

Results: The results obtained from total 21 questions categorized into 4 steps to assess convenience and satisfaction with CAD software for implant design were as below. 1. Bringing basic information and files (4 questions) Experienced practitioners presented significant difference in ‘UI design including display composition and menu is convenient to use’ and ‘UI design of the software is sophisticated’ whereas inexperienced practitioners presented that in ‘UI design including display composition and menu is convenient to use’. In this step, the satisfaction with ExoCAD was significantly high in both groups. 2. Setting the condition before designing abutments (8 questions) Experienced practitioners presented significance in ‘Correcting margin line is easy’; however, no significant difference was found in all other questions from both groups. In this step, experienced practitioners and inexperienced practitioners highly appreciated 3DSystem and ExoCad, respectively. 3. Setting abutment design (8 questions) Experienced practitioners presented significance in ‘Adjusting the upper abutment to desiring size and shape is easy’ and ‘Setting function for upper and lower abutment is various’; however, no significant difference was found in all other questions from both groups. Nevertheless, experienced practitioners highly appreciated 3DSystem with significance in this step. 4. Overall satisfaction (1 question) Both the two groups highly appreciated ExoCad software.

Conclusion: ExoCad software was highly appreciated in overall from the assessment of convenience and satisfaction with two kinds of CAD software for dental implant. However, experienced practitioners highly appreciated 3DSystem in step 2 and 3 that are the core of the designing process. Hence, 3DSystem CAD software with improvement in other parts can be widely used in clinic.

Articles: Liqiong Deng, Douglas E. Turner, Robert Gehling and Brad Prince. User experience, satisfaction, and continual usage intention of IT, Eur J Inf Syst 2010;19:60–75 D. J. Fasbinder, Computerized technology for restorative dentistry, Am J Dent 2013;26:115–20 Ji-Hyun Park, Jong-Eun Kim, June-Sung Shim, Digital workflow for a dental prosthesis that considers lateral mandibular relation, J Prosthet Dent 2017;117:340-4

  View Poster
Poster Thumbnail
Design Optimization of Reduced-Diameter Implants by Artificial Neural Network

Jason Griggs, PhD – Associate Dean for Research, University of Mississippi School of Dentistry

Purpose of the Study: The objective was to train an artificial neural network (ANN) to predict the fatigue limits of dental implants.

Methods: Four commercially available reduced-diameter implant systems (RDIS) were investigated: Straumann Narrow Neck, Biomet 3i Osseotite MicroMiniplant, Nobel Biocare NobelReplace, and Biomet 3i Osseotite Certain. Step-stress accelerated lifetime testing was performed on the RDIS to determine the fatigue limit for each design. MicroCT images (Skyscan1172, Microphotonics) of the four RDIS were analyzed. Twenty-four design parameters were identified, and measurements were made using Mimics interactive image processing software (Materialise, 9-micron resolution). Linear stepwise regression was used to identify the seven most significant design parameters, and these were used as the input vector to predict the fatigue limit in a feedforward error-backpropagation ANN having one hidden node. The learning ratio was decreased from 1 to 0 over 1,500 iterations.

Results: The ANN achieved a notable prediction accuracy (R-squared=0.99995). The effects of implant body inner diameter, abutment screw thread height, and abutment screw head diameter were non-linear and could account for most of the variation in fatigue limit between implant systems.

Conclusion: The ANN was successfully trained on the commercially available implant systems and may be a useful tool in predicting the implant design that corresponds to maximum possible fatigue limit. However, some of the design parameters are confounded in the current commercially available systems, so future studies should train an ANN on the fatigue lifetime predictions from finite element models of hypothetical implant systems in which the factors are not confounded.

Articles: None cited.

  View Poster
Poster Thumbnail
Displacement of Dental Implant Body into Oral Soft Tissues: A Case Report

Kazumasa Yoshida, DDS, PhD – Associate Professor, Department of Oral & Maxillofacial Surgery, Nippon Dental University Hospital

Hirobumi Shoji, DDS, PhD – Associate Professor, Department of Oral & Maxillofacial Surgery, Nippon Dental University Hospital

Purpose of the Study: Dental implant displacement into the maxillary sinus has occasionally been reported; however, dental implant displacement into oral soft tissues is rare. We report a case of dental implant displacement into the buccal mucosa and some discussion.

Methods: Case: The patient was a 62-year-old man. First Visit: March 2010 History of Presenting Illness: Dental implantation was performed for the maxillary left second molar at a private dental clinic in November 2009. The patient suffered from persistent discomfort in the left buccal area and visited another doctor who referred him to our hospital in February 2010. The X-ray showed a metallic radiopacity in the retromolar area of the left side of the mandible. The patient was referred to our hospital. Local Findings: A removable solid body was felt around the orifice of the parotid duct inside the left buccal mucosa. Imaging: Computed tomography revealed a metallic radiopacity present subcutaneously in the left buccal area outside of the masseter muscle in two places at the level of the mandibular foramen.

Results: Treatment and Course: Under general anesthesia, an oral surgeon detected the positions of the implant body using an implant detector, which was developed as a metallic detector for implant treatments. An operator made an incision from the maxillary gingivobuccal fold to the buccal mucosa and flapped deeply and bluntly into the tissues beneath the buccal mucosa. Subsequently, an implant cover screw and an implant body were removed from the buccal fat pad.

Conclusion: As mild-to-moderate trismus developed after the implant placement, we suspected implant displacement. The displacement may be because of the insertion of the implant in a wrong direction, sliding the implant body to the buccal side, penetrating deeply into the buccinator space through the tissues beneath the buccal mucosa and buccinator, and reaching the anterior border of the masseter muscle through the buccal fat pad. When foreign bodies are removed from the oral soft tissues, identification of the position is difficult; therefore, the implant detector was useful for second stage implant surgery. We encountered a case of dental implant displacement into the oral soft tissues. Therefore, we believe that improved skills are required to perform careful and safe dental implant surgery.

Articles: 1. Bibra A, Mahajan S, Dhawan R. Retrieval of dental implant displaced into buccal space: A rare case report. IJOICR. 2016; 7: 17−19. 2. Shoji H, Adachi M, Yoshida K, Shibata A, Hasegawa I, Shirakawa M. Clinical study of accidental displacement of dental implant into maxillary sinus. Hosp Dent Oral-Maxillofac Surg. 21: 13−14, 2009. 3. Gnigou M, Goutzanis L, Sarivalasis S, Petsinis V. Retrieval of displaced implants inside the maxillary sinus: Two case reports and a short review. Int J Implant Dent. 2019; 5.

  View Poster
Poster Thumbnail
Effect of Mmebrane Perforation During Sinus Grafting on Implant Survival rate: retrospective study

Sarah Bukhari, BDS, MS – Fellow (Advanced Education Program in Implant Dentistry), LLU

Yueh-Ling Chao, DDS – Fellow (Advanced Education Program in Implant Dentistry), LLU

Purpose of the Study: Maxillary sinus augmentation is a predictable procedure with high success and low complication rates.1-3 The most common complication of with maxillary sinus augmentation is perforation of the Schneiderian membrane ranging from 10-55%.4-9 The incidence of perforation has been attributed to several factors; the anatomy of the sinus, the presence of septa, the thickness of the membrane, operator error, overfilling of the sinus.6,7 10Evidence in the literature is contradicting in regard to the correlation between sinus membrane perforation (SMP) and post-operative complications. The aim of this retrospective study is to evaluate the correlation between SMP and post-operative complication; graft failure, implant failure, bone formation. Taking into consideration operator experience, perforation size and location, sinus anatomy and repair technique.

Methods: Patient Selection This retrospective study was approved by the institutional review board of Loma Linda University. The treatment records of patients who underwent sinus augmentation (lateral approach) and subsequence implant placement between June 2012 and June 2018 were reviewed. Inclusion Criteria: Potential subjects for exposure rate comparison must meet ALL of the following criteria: Be over 18 years old at the beginning of treatment. Have sinus augmentation (lateral approach) procedure without implant placed simultaneously. Additional criteria for implant survival rate comparison: Receive implant placement after sinus graft is healed and have a record of more than 1-year follow-up after implant placement. Data collection Patient demographics (age and gender), tobacco usage (smoking or non-smoking), date of sinus augmentation, augmented site, initial bone height, membrane perforation, perforation size, perforation management, graft outcome, and sinusitis. Perforation rates were reported in the following categories: Surgeons’ surgical experience: >5 years (E) or <5 years (LE) Smoking habit Cross-sectioned images were measured using CBCT (i-CAT, Imaging Science Internation, Hatfield, PA) before sinus augmentation (T0), right after sinus augmentation (T1), and before or right after implant placement (T2). The CBCT were transferred and opened using an implant planning software program (InVivo 6, Anatomage Dental, San Jose, CA). Superimposition function was used to measure the same area from T0-T1-T2. A preplanned implant position (P1) was selected as point of measurement based on radiographic template. Additional implant positions were selected 1mm mesial (P2) and distal (P3) to P1. After points of measurement were obtained, the area-measuring tool in InVivo 6 was used to measure cross-sectioned images at P1, P2, and P3 of images T0, T1, and T2. Average value of P1, P2, and P3 from each CBCT images (T0, T1, and T3) were calculated to obtain the height before sinus augmentation (mm), height right after sinus augmentation (mm), and height after healing (mm). After obtain the height of the three images (T0, T1, T2), quantitative height of grafted bone placed (QGBP), quantitative height of grafted bone remained (QGBR), quantitative grafted bone height loss (QGBDL) and Percentage grafted bone height loss (PGBDL) were calculated using these formulas: Quantitative height of grafted bone placed (B1) = height right after GBR – height before GBR Quantitative height of grafted bone remained (B2) = height after healing – height before GBR Quantitative grafted bone height loss (B3) = height right after GBR – height after healing Percentage Grafted Bone height Loss = (B3/B1) x 100 The mean QGBP, QGBR, and PGBDL of the perforated and non-perforated groups were calculated for each type of membranes. Statistical Analysis The sinus membrane perforation rates associated with each recorded parameter were represented using descriptive statistics. PGBDL of perforated groups and non-perforated groups among each barrier were compared using independent samples Mann-Whitney U PGBDL among perforated membrane was compared by independent-sample Kruskal-Wallis test. Intra-examiner reliability was tested using SPSS® intraclass correlation coefficient (ICC) and was considered adequate at 0.90. The level of statistical significance was set at P < 0.05. The methodology was reviewed and approved by an independent statistician.



Articles: References: 1. Ulm, C.W., Solar, P., Krennmair, G., Matejka, M. & Watzek, G: Incidence and suggested surgical management of septa in sinus-lift procedures. Int J Oral Maxillofac Implants. 1995;10: 462–465. 2. Khoury, F. Augmentation of the sinus floor with mandibular bone blocks and simultaneous implantation: a 6-year clinical investigation Int J Oral Maxillofac Implants. 1999;14: 557–564. 3. Vlassis, J.M. & Fugazzotto, P.A. (1999) A classification system for sinus membrane perforations during augmentation procedures with options for repair. Journal of Periodontology 70: 692–699. 4. Misch CE: The maxillary sinus lift and sinus graft surgery, in Misch CE, (ed). Contemporary Implant Dentistry. St Louis, MO: CV Mosby, 1999, pp. 469–495. 5. Pikos MA: Maxillary sinus membrane repair: Update on tech- nique for large and complete perforations. Implant Dent 17: 24, 2008 6. Schwartz-Arad D, Herzberg R, Dolev E: The prevalence of surgi- cal complications of the sinus graft procedure and their impact on implant survival. J Periodontol 75:511, 2004. 7. Bergh van den JPA, Bruggenkate ten CM, Disch FJM, et al: Anatomical aspects of sinus floor elevations. Clin Oral Implants Res 11:256, 2000 8. Shlomi B, Horowitz I, Kahn A, et al: The effect of sinus mem- brane perforation and repair with Lambone on the outcome of the maxillary sinus floor augmentation: A radiographic assess- ment. Int J Oral Maxillofac Implants 19:559, 2004. 9. Timmenga NM, Raghoebar GM, Boering G, et al: Maxillary sinus function after sinus lifts for the insertion of dental implants. J Oral Maxillofac Surg 55:936, 1997. 10. Marin S, Kirnbauer B, Rugani P, Payer M, Jakse N. Potential risk factors for maxillary sinus membrane perforation and treatment outcome analysis. Clinical implant dentistry and related research. 2019 Feb;21(1):66-72.

  View Poster
Poster Thumbnail
Investigation of Bone Augmentation using an Autologous Tooth as the Bone-graft Material: Application in a Hydroxyapatite-coating Implant

Toshihiro Nakatsuka, DDS, PhD – Med. Corp. Maitreya, Keikodo Oral & Dental Clinic

Purpose of the Study: Generally, autologous, xenogenic, and artificial bone grafts are used to fill bone defects during implant placement. I have recently used an autologous tooth as the bone-graft material (My Teeth Bone: MTB; Tooth Osteoplant graft: Top graft), which was crushed and processed from the patient’s own tooth. In this study, I report cases of an autologous tooth bone graft, which was applied to a hydroxyapatite-coating implant (HA implant) and showed favorable results.

Methods: Preparation of an autologous tooth bone graft: Soft tissues adhering to the autologous tooth extracted from a patient were removed as much as possible. The autologous tooth was washed thoroughly with saline and crushed using a crusher to 250–1000 μm. The crushed tooth was immersed into a 0.6-M hydrochloric acid solution and demineralized using a dedicated machine (Top Graft MaterializerTM, GeoMedi, Fukuoka, Japan) in vacuum while leaving the growth factors. Subsequently, the demineralized tooth was washed and finished into a bone substitute (MTB/Top Graft). MTB/Top Graft was filled in the bone defects at the time of HA-coating implant (AQB TM, ADVANCE, Tokyo, Japan) placement. We investigated a total of 32 cases (18 men and 14 women; 13 in the anterior region, 8 in the premolar region, and 11 in the molar region of the jaws) from November 2016 to February 2019.

Results: The results showed that the treatment period was shortened in all cases treated with MTB/ Top Graft. To date, the postoperative course in all the cases have been uneventful, with no bone resorption or infection.

Conclusion: The MTB/Top Graft appears to have a highly osteoconductive potential, as it is a bone graft processed from the autologous tooth (the patient’s own tooth). Similarly, good results were seen in cases using MTB/Top Graft during Dennis P Tarnow's ice cream cone technique (USA) and Homa Zadeh's vestibular incision subperiosteal tunnel access method for bone augmentation (South Korea). Bone formation must be promoted because of the synergistic effect between this material and a HA-coated implant, which is an osteoconductive material. Comparative studies on this material applied to other types of implant materials are needed. The sample size was small, and clinical data were statistically insufficient. Further studies on more patients are needed for widespread clinical use.

Articles: 1. Sarala C, Chauhan M, Sandhya PS, Dharmendra CH, Mitra N. Autogenous tooth bone graft: Ingenious bone regeneration material. Indian J Dent Sci. 2018; 10: 56−59. 2. Kim ES. Autogenous fresh demineralized tooth graft prepared at chair side for dental implant. Maxillofac Plast Reconstr Surg. 2015; 37: 8. 3. Kim YK, Pang KM, Yun PY, Leem DH, Um IW. Long-term follow-up of autogenous tooth bone graft blocks with dental implants. Clin Case Rep. 2017; 5: 108−118.

  View Poster
Poster Thumbnail
Maxillary sinus lift without grafting

Kyung Jin Kim, DDS – Resident, OMFS

Purpose of the Study: The maxillary sinus lift procedure combined with bone graft has been used to allow for proper implant placement in the atrophic maxillary posterior region. However, the risk of complications such as infection may increase due to the complexity and extended length of the procedure. The graft-free maxillary sinus lift technique is less susceptible to such risks as it is a simpler operation. The purpose of this study is to evaluate the tenting effect of implants by analyzing the degree of bone formation around implants placed after maxillary sinus lift without grafting

Methods: A total of 49 implants were placed in 26 patients(11 women and 15 men). Maxillary sinus lift without grafting was done at all sites and implants were placed simultaneously. Panorama and CBCT were taken preoperatively and at 6 months postoperatively. Radiographs were used to evaluate the height of the residual bone, the width of the sinus as well as the presence of lesion within, the amount of bone formation, and the location of adjacent teeth.

Results: A total of 49 implants were placed. No patients developed sinusitis or infection, but 3 implants were removed. The remaining 46 implants is healed well, neither infection nor implant mobility was observed on initiation of loading force from the prosthetic components. Implant survival rate was 93.5%. The gained bone morphology showed three types: tent type, flat type and dehiscence type. Most cases (total 35) showed tent type. The five cases of dehiscence-type were excluded from bone height measurement because it was difficult to determine the bone height. The residual bone height ranged from 2.4 to 9.2 mm, with an average height of 6.5 mm. Implant fixture length measured between 10 to 13mm with an average of 11.1mm. Total bone height ranged from 10 to 13.2 mm, with an average height of 11.2 mm. The range of increased bone height ranged from 2.2 ~ 7.6mm, with and average of 4.7mm. Pearson correlation showed that maxillary sinus width, and increased bone height were not statistically significant and only the amount of residual bone height and increased bone height were significant. In the case of residual bone height of 5mm or less, the increased bone height was about 2mm higher than that of 5mm or more. However, it does not mean that the smaller residual bone has the better osteogenesis capacity. In other words, if the maxillary sinus was lifted without grafting, the increased bone is formed only to the length of the implant fixture.

Conclusion: (1)Sinus lift without graft materials is an effective surgical options for pneumatized Mx. posterior area, but at least 3mm residual bone is needed for implant success. (2)The gained bone morphology is most likely to show tent type and to exist just at the same level to the fixture apex. (3) Mx. sinus width and adjacent teeth do not affect the amount of new bone formation. Only the fixture length is significant.

Articles: Kumar DS. Effect of maxillary sinus floor augmentation without bone grafts. J Pharm Bioallied Sci. 2013; 176–183

  View Poster
Close this panel
Browse By Track
Browse By Poster Author
Browse By Title
Close this panel
Stuff for Poster Tools
Stuff for Share


Technical Support

(877) 426-6323


SUBMIT FEEDBACKfeedback icon

We really appreciate your feedback on the eventScribe website. We use the data to improve the experience and simplify the process for users like you.


Log In / Sign Up

Already have an Event Scheduler or mobile app login? Login with those details. If not, create a login.

Log In   Sign Up
Access your bookmarked poster and notes by logging in ...   Sign up to take notes on poster, bookmark poster, and submit feedback.
  Lost your access key?      
You need to be logged in to bookmark posters, save notes, or rate posters.