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Implant TribuneAsia Pacific Edition | 10/201518 « If you are not a DVT owner, oral surgeons (specialists) and diagnostic radiology clinics are appropriate contact addresses. Regard: For the intended 3-D image, always allocate theexactDVTarea,detailsandviewer suitable for your PC software. The ex- pensesbothoftheDVTandthedigital analysis and evaluation are subjects toprivatecash. Interimplant distance Ifanimplantisplacedadjacenttoa tooth,theinterdentalpapillaremains. If two implants are inserted side by side,thesupracrestalbiologicalwidth andthepapillaasresultdisappear,in- dependentoftheimplanttypeused.7 Theeffectsofimplantswithplatform switching,concaveabutments,micro- machinedneckorimplantabutment micro-movements onto the stability of crestal bone and soft tissues are limited to subclinical notice.8, 9 The interimplant distances primarily fol- low prosthetic requirements of the residual dentition.10 From anatomy, thepresentrulesoccur: 1.Minimal distance between single- rootedteethincl.premolars:7mm. 2.In molars interimplant distances ofatleast11mm(Fig.8). For appropriate implant place- ment according to prosthetics, the local bone anatomy is often inade- quate, especially in patients with cross-bite or long-term periodontal damage etc. (Fig. 9). If the clinical setting implicates deficient implant bone support, 3-D digital imaging of alveolar bone including individual- ized implant positioning with dia- meter-reduced implants is allocated. Note: Prior to surgery, calculate addi- tional efforts, extentand expenses of alternativeaugmentation,bonegraft- ingorallogeneicbonegraftsincluding pedicleflapsurgeryandinfectiondue tosofttissueadvancements. Implant placement Perfusion Maintenance of vascularized im- plant bone is indispensable to avoid furtherperiimplantdamageasresult of spongious bone tissue injury dur- ing implant surgery (early implant failures). Within implant insertion, bleeding of cortical bone following drilling is a necessary requirement for uneventful healing and integra- tionoftheimplantintosurrounding tissues (Fig. 10).11 The following step by step procedure has been proven effective: a)Utilization of keen pilot und multi- use tapping drills (renew early, otherwise high drilling forces and danger of deviation from drilling axisoccur). b)Intermitted implant bed prepara- tionunderpermanentcoolingwith 0.9%saline. c)Prior to implant placement, wait until implant bed has been replen- ishedwithblood. d)Wetting of implant surface with bloodpriortoimplantinsertion. e)Limited rotation speed <800r.p.m during implant bed preparation, hand implant placement with torque key, max. 10–30Nm, if applicable. A slight subcrestal position of the implant is advisable as drilling end- point.12 To ensure healing, a primary fixation of the implant is mandatory for all implant types (cylindrical, root-formed etc.), bone quality and anatomical localization. The authors strongly discourage from further „screwing“ to avoid ongoing tissue injuryoftheimplant-bone-interface.13 Periimplant tissue (volumen) Duetoalveolarbonedefectsresult- ingfromtoothremoval,periodontitis ordysfunction,theconditionsofperi- implant keratinized gingiva around implants are not adequate.14 Safe- guarding implant planning and sur- gery,theadditionalduesofsofttissue surgery to enlarge periimplant gin- giva should be implemented into the quotation: Enlargement: Initially, implant planning (not to forget cast models) and implant placement. During implant insertion into local bone, enlargement of peri- implant gingiva with a ridge incision 1–2mmorallyisusuallyadequate. In lateral augmentation in the maxilla, periimplant enlargement is frequently mandatory as result of flapadvancementtocoverthedefect. During healing and prior to implant exposure, vestibuloplastic surgery with free autogenous gingival graft from palate at implant site in a sep- arate visit (Figs. 11 & 12). In individ- ual cases and edentulism in the mandible, periimplant enlargement with Edlan Mejchar-Vestibuloplastic surgerytocreateattachedmucosaby apedicleflapwithadequateesthetics prior to implant placement. Also, to achieve soft tissue protection follow- ingimplantinsertion(Figs.13&14). Thickening: To safeguard implant placement and protect against periimplant dis- eases,anadequateperiimplantwidth ismoreneededthansofttissuethick- ness. Following thickening by free autogenoussofttissuegraftsfromthe palate or roll flap, loss of periimplant dimension is anticipated due to shrinkageandfurtherscarformation. Periimplant thickening is limited to individual patients with esthetic needs in the upper front of the max- illa. Shortcomings following healing, scar formation, normal biologic re- sorption and failing of long-term stability are usually compensated by individual prosthetic abutments and ceramic crowns with a wide peri- implantshoulder. Short and diameter-reduced implants The usage of short implants <9mm demands minimalization of surgery.Implantplacementandheal- ing are customer-friendly. However, micro-incision surgery requires ad- ditional efforts by 3-D imaging (DVT) during planning and sensitiveness inclinicalrealization.Evidence-based clinical data for short and diameter- reduced implants are inconsistent and industry-driven. Biomechanical research underestimates the func- tional adaptive capacity of implant bone.15, 16 In clinical practice, vertical alveolarbonelossisthemostfrequent demand: Mandible: 1.Advanced alveolar bone loss in pre- molarsandmolars(numerous). 2.ProximitytoN.alveolaris. Maxilla: 1.Close anatomical relationship to sinusmaxillaris. 2.Atrophied or edentulous maxilla following longterm appliance of removabledentures. Horizontal alveolar bone defects, as result i.e. of longstanding perio- dontitis, are compensated surgically during implant placement to avoid extended implanto-prosthetic abut- ments susceptible for recurrent soft tissue infection (Fig. 15). Fixed im- planto-prosthetic restorations of the partially endentulous mandible are achieved with axially screwed, un- cemented and unlocked crowns to improve hygiene and avoid further damage by cementing and peri- implantitis. Integration in clinical practice is successful with focus on tissue biology and both renunciation frommechanicaldentistryandinter- lockingtheories. Diameter-reduced (<4mm), small implants (minis) allowing transgin- gival healing. According to their material properties (fracture) and restricted implanto-prosthetic indi- cations and compatibility, Minis are limited to individual applications in multimorbid subjects with eden- tulous mandible, enhanced risk for surgery i.e. advanced diabetes melli- tus or hematopoietic diseases and handicapsfororalhygiene.17 Augmentation and revision Except for sinus floor grafting, the number of augmentative implant surgery is declining and confined to reconstruction following trauma and tumor by vertical distraction or individual prosthetic or esthetic set- tings.18 The indications for surgical augmentation during implant place- mentinclude: a)Toothlossincross-bitesettings. b)Lateral alveolar bone defects (pre- molarsandmolars). c)Modelling of periimplant bone in esthetically demanding situations at incisors and canines (emergence profile). Theauthorshaverecentlyreported about the use and implementation of autogenous bone and spongious bonechipsandtheirsyntheticalalter- nativesinimplantsurgeryindetail.19 The regressive developments of implant augmentation in clinical practice implicate direct recommen- dations for surgical revision of peri- implant defects. The following pro- cedureisadvisable(Tab.I).20 Mucositis: •Defect depths ≤3mm: Oral hygiene andimplantcleaning(hygienist). •Defect depths ≤4–5mm: Addition- ally 0.2% CHX, Er:YAG decontami- nation,ifapplicable(dentist). •Defect depths ≥6mm: Periimplant plus periodontal cleaning, systemic antibiotics: amoxicilline 500mg 20 T and Clont 400mg 20 T, t.i.d for 7days. Together with decompensation by occlusal appliances (mentioned above), safeguarding by front-canine equilibration and removal of im- planto-prosthetic restoration, the clinical situation often improves. Theprocedurecanbeeasilyrepeated. The recommendation to removably screwfix implant restorations axially (only premolars and molars) is be- coming a strong relevance in the treatmentofperiimplantdamage. Periimplantitis: Advanced periimplant damage with circumferential angular bone lossencompasses •Defect depths ≥8mm: Explanta- tion,surgicalrevision(ifapplicable). In these clinical settings, implant removalwithrepeatedinsertion,aug- mentation (where appropriate) and prostheticrestorationfollowingheal- ingisadvocated,iftheclientapproves the treatment. In periimplant dam- age,thebenefitofrapidimplantbone healing following insertion of short and diameter-reduced implants be- comesobvious.Inindividual,strategi- callyimportantimplantsites,i.e.canine implant area in edentulism, revision is emphazised with the following surgicalprotocol(Tab.II).21 •Removal of implanto-prosthetic restoration,ifscrew-fixed. •Horizontalridgeincisionwithamu- coperiostal flap and mesial vertical extension. •Curettageofimplantbonedefect. •Irrigation with 0.2% CHX, supple- mentedbyEr.YRG-decontamination. •Stimulation of bleeding plus auto- genousbonegraftsfordefectfilland reconstruction,defectcoveragewith rotatedpediclesofttissueflap. •Close, tension-free wound closure, nofunctionalloading. •Systemicantibiotics. Summary Thepreventionofperiimplantdis- eases is based on a comprehensive analysis, evaluation and planning priortoimplantplacement.Securing the residual dentition from perio- dontal disease, on time removal of compromised teeth and functional decompensationwithfocusonfront- canine equilibration are the key is- sues during implant planning. Prior tosurgery,DVTdiagnosticevaluation is required if proximity to anatom- ical structures is anticipated, and short and diameter-reduced im- plants are advocated to determine interimplant distances and safe- guard implant treatment. Implant placement succeeds with minimal mechanical loading of implant bone and implementation of perfusion during surgery. Periimplant enlarge- ment is scheduled during implant healing, either by free gingival graft or pedicle flap. Premolar and molar implant restorations are screw-fixed axially to ease handling in case of periimplant damage. The concerted action of eliminating inflammation, stabilizing function while minimiz- ing surgery secures implant success, prevents periimplant diseases and promotes the reputation of dental health care providers in the com- munity. Theauthorsappreciatetheencouragement andsupportofDrGerhardKochhan,Düssel- dorf,inperiimplantcooperation. Editorialnote:Alistofreferencesisavailable from the publisher. This article was pub- lished in the 03/2015 issue of implants, internationalmagazineoforalimplantology. IMPLANT NEWS Professor Rainer Buchmann is a specialist in pe- riodontics and preventive den- tistry. He works at aprivateprac- tice in Düssel- dorfinGermany andholdsteach- ing positions at Heinrich Heine Univer- sity Düsseldorf and the University of Seville in Spain. He can be contacted at info@perioimplant.eu. Surgical Reentry 1.Removal of suprastructure (screw-fixed). 2.Horizontalalveolarridgeincisionwithverticalmucoperiostalflapreflection. 3.Intrabony defect curettage. 4.0,2 % CHX irrigation,Er:YAG-decontamination. 5.Stimulation of spongious bleeding plus autogenous bone grafts for defect fill and reconstruction. 6.Close,tension-free defect closure,no functional implant loading. 7.Systemic antibiotics. PeriimplantTherapy Step Defect (PD in mm) Treatment A ≤ 3 mm Oral Hygiene + IMP Cleaning B ≤ 4–5 mm CHX 0.2 %,Er:YAG C ≥ 6 mm Systemic Antibiotics D ≥ 8 mm Implant Removal/RegenerativeTherapy TableII:Surgicalrevisionofadvancedperiimplantbonydefectsislimitedtosingleclinical settingsduetothetimeandextentofsurgeryandadditionalpatientexpenses. Table I: Key treatment issues to combat periimplant damage,to a large extent being preventedbyearlyandcarefullimplant planning. DTAP1015_17-18_Buchmann 14.10.15 09:14 Seite 2 DTAP1015_17-18_Buchmann 14.10.1509:14 Seite 2