Lower Molar Immediate Implants

In this section, three topics are discussed.  Where to place implant?  Bone graft is necessary?  CT is mandatory?

To answer the first question, we need to know which molar to receive implant, whether the septum is present or not, and the size of the septum.  The first molar has two widely separated roots.  The implant should be placed in the septum.  Osteotomy is initiated in the septum either before or after extraction of the roots.  If one socket is severely affected, the implant should be placed in the other healthy one; the septum should be pushed to the affected socket using osteotomes so that the implant is finally placed more or less in the center of the socket.  If the one socket is too large, the implant may be placed in the other socket. In case one socket is close to the root of the neighboring tooth, the other socket should be chosen as an implant site.  When the septum is destroyed by lesions, the largest implant is placed in the socket.  The second molar usually have fused roots.  A single large implant (2) is placed to prevent socket collapse post-extraction and achieve ideal restoration.  When the second molar has two separate roots, the implant may to be placed in the mesial socket or the septum.  For a single socket of the 2nd molar, the implant still has to be placed in the middle of the socket or in the mesial slope of the socket.

Is bone graft necessary for immediate implant?  It should be case dependent.  Bone graft is not necessary as long as osteotomes and reamers are used, large implants are placed, and the remaining space is small.  When the socket defect is large and implant threads are exposed, bone graft is essential to close the space and prevent periimplantitis.  If the latter does happen, bone graft after debridement is a practical solution.

Is CT mandatory?  Probably not.  But it is when the inferior alveolar nerve or mental loop is not so distinct on 2-D X-ray or lack of experience on immediate implant, particularly for multi-rooted teeth.  As time goes by, observation ability increases. The socket can provide the most precise 3-D image for surgeons.  Most of information is available if the brain and eyes are active.  Concentrate on every step of implant placement.  Give yourself ample time to finish surgery.  For example, every step of immediate implant can be remedied.  If a drill, osteotome and even implant is off, take it out and redirect it.  You are surprised to find that immediate implant has more flexibility than delayed implant.  The best of all, if immediate implant cannot be placed as planned, there is always a second chance.

Since peri implantitis in the molars appears more common than that of the premolars and anterior teeth, new protocols are proposed to reduce the incidence (2016_06_26).

1st Molar 2nd Molar (Anatomy)
Feature Design Surgery Follow-up Feature Design Surgery Follow-up
Furca Lesion   Suture   Challenges   Mesial slope, Cement Bone Graft Removal
Root Fracture Reamer Provisional   Large Defect (WZN)   Redo, 1st Placement  
One Piece   Trajectory   Paresthesia   Prevent  
Infection   Fistula (Papillae)    Shallow Placement   Redo  
Septum   Trajectory   Massive Destruction   8x14 mm Implant  
Which Socket Proximity Septum   Buccolingual Trajectory & Position Get it Done  
Single Socket   Large Implant   Infection Near IAN Debride Pain Control Recovery
No Immediate Limited Ortho Trajectory Close to Root   Close to IAN Plan Intrabone Injection Uneven B-L Plates
Bruxism Root Fracture New Bone Depth   Delayed Placement Pain 2 3 Safer Surg Mesial Slope Redo
No Bone Graft: Immediate (30) Delayed (19) Septum Split Graft 2 No Drill   No Paresthesia  
Immediate Tooth Delay     Which Socket Never too big Mesial Socket Perimplantitis Redo 2
Delayed Implant Narrow Ridge Ridge Split, Narrow Implant   Indistinct IA Canal   Short Implant  
Warning Signs for Paresthesia     Huge Socket   Implant Forms Osteotomy  
Periodontitis Bone Graft Thread Exposure   Instant Decision   Taps Form Osteotomy  
        #31 Endo-Perio Lesion Unilateral Mastication Overloading  
Limited Clearance Immediate FPD Extra Support   Residual Roots Safety Safe Margin  
Crack Syndrome Septum slot Submerged   Insidious Infection Soft Bone    
Perio-Endo Lesion Bony Defect Lingual Plate Repair   Delayed Implant Immediate Crowns    
Buccal Infection   Osteotomy Deviation   Threads Covered by Bone Control of Infection Implant Threads Covered by Graft  
Bone-level Implant   Taper of Implant   Partial Edentulism Immediate Bridge    
Diabetes   Bone Graft   Uneven M-D Crests Why Mesial Slope Overcorrect  
Uneven M-D Crests Distalize Septum Hemisection   Severe Bone Loss Long Abutment Not Completely Seated  
Possible Root Crack Avoid Lesion 2 Place in middle of Septum   Severe Distal Bone Loss Osteotape Wall (TST) Mismatch of Tap/Implant  
Severe Bone Loss Long Abutment     After LR Bridge Removal  LL Bridge Fails Atypical Immediate Implant  
Recall Patient Re-emphasis     Long-termed Loss of 1st Molar Change Position Wax up & Surgical Stent  
Crown Fracture Septum Placement     Nerve unidentified No drill Implant Shorter than Socket  
Root Fracture   Deviation Placement   Delayed Implant Stopper Shorter, Safer  
Long Curved Roots   Septal Struts for Stability   Failed Bridge Splinting Immediate Surgical Stent  
Endo Failure Septal Struts Tripod Septum   Defect Caused by 3rd Molar Mesial Socket, #18 Septum Fractures  
Severe Atrophy Post Extraction Is Iatrogenic   Reduced Bone Height Due to   Non Immediate Implant  
Short Statue Short Implant Solution to Challenge   Healing Socket Bone Expanders Mesial Socket Placement  
Implants at Healed Sites   No Recession   Healed Site   Measure Repeatedly, Extrawide  
Design for ... Success Threads Healed Sites Bone Height Thick Gingiva, Long Cuff  
Perio & Bruxism Bone-level Implant Incomplete Implant Seating   Difficult to Take Preop PA   CT  
Immediate FPD Unlimited Height Soft Bone Endo/Perio/Trauma Minimal Drilling
Furca Lesion   Short Beauty   Detoxify Healed Socket   Keep 3rd Molar for Temp  
Immediate Provisional Socket Preservation Implant Failure; 2nd try   What to Do Next? Underprep Different Types of Abutments  
5 Month Post Extraction Bone Condensation?     Ambiguous Superior Border of Inferior Alveolar Canal Implant Placement Level: Coronal  
Severe Gingival Recession How to Handle It? Non-Resorbable Membrane   2-Year Follow-Up   Trajectory of Immediate Implant  
Tooth Fractures 3 Roots Large Immediate Abutment Periimpl 2 Unexpected Molar Implants   Immediate Action  
Healed Site Systemic Approach 5.5 mm Implant   Indistinct IAC Limited Height Adjustments of Osteotomy  
Atrophic, Porous Crest Bone Expansion Thread Exposure   Periapical Radiolucency Where to Start Osteotomy Mesial Slope: D1,2 Bone Food Impaction
Persistent Socket Outline Underprep Executed as planned   Periodontally Affected Submandibular Fossa Failed Placement Flapless Surgery
#30 Narrow Crest; #19 Short Height UF; Extra Wide 1-staged Ridge Split 14/19 Guide   Bicon Implant Immediate Provisional Perio Dressing  
Convert #29-32 FPD to Short, Small Implants 3rd Molar Implant?   Close to Submandibular Fossa & Inferior Alveolar Canal Systemic Approach to IAC 31 Bone level implant
Mesial Root Fracture Osteotomy Site Bone-Level Implant   Sufficient Height Opposing Supraeruption Prosthetic Intrusion  
Narrow Mesiodistal Space 1-Piece Implant     Missing Four Molars Submerged LL Placement, LR  
Neighboring Roots Used As Reference for Drill Depth Ridge Split   Impacted 3rd Molar Needs to be Extracted?    
Limited Buccolingual Width Treatment Options 4.5 mm Implant   Extraction of #31 and 32 Implants at #30 and 31    
Severe Bone Loss Over Prep Provisional Stabilizes Implant   Narrow Crest 2-Staged Ridge Split    
Periodontitis with Enough Bone Mesial Osteotomy Lingual Nerve Anesthesia   Narrow Ridge (#18,19): Poor Design & Execution Results in Compromised Result #30 Narrow Implant
Sufficient Bone Depth Control Subcrestal Placement   Crack Tooth: Implant Engages B-L Walls    
3 Fistulae Around Mesial Root Distal Osteotomy Bone Graft in Layers   Multiple Missing Teeth with tilted tooth Deep Placement  
Early Implant Subgingival Margin Bone Expansion   Occlusal Trauma Posterior Support Even Edentulous Space  
Convert FPD to Implant Ridge Reduction Localized Ridge Trimming   Implant Placement at #18 After #17 Extraction Periapical Radiopaque Lesion  
Severe perio & Bruxism, Implant Placed Next to IAN Angled Abutment   From Radiolucency to Crown Fracture Depth of Osteotomy  
Residual Roots 4-Step Grafting Drilling on Maimed Septum   Opposing Supraeruption Implant Should be Shorter Placed Deeper 2nd Case  
Unilateral Mastication Longest Implant Bone Loss of Next Tooth   Ordinary Case Precise Placement    
Partial Edentulism No Immediate Provi Longer, Marked Parallel Pin   Root Resorption (Bruxism) Abutment Selection Incomplete Abutment Seating  
Tripod Septum, Sufficient Height #3 Supraerupted Osteotomy via Roots Redo Vertical Bone Loss   Extra Wide Implant  
Large Bony Defect (silver point) Stopper Control Implant Plac. Depth Prevent P Post Socket Preservation No Drill Osteotomy    
Long Term Follow Up   Bicon Implant   Pointed Ridge Short, Wide Implant Ridge Reduction with Handpiece Immediate Redo
Vertical Fracture at Root Tip Septoplasty Short Implant, Much Graft   5 Years Post Extraction Bone Height Estimation    
Ortho-Induced Bone Growth   1-Piece Implant   3rd Molar Impaction Mesial Socket Placement No Tap No Immediate Implant  
LL Tripod Septum Larger Abutment Osteotomy Prior to Extraction Ortho Thin/Perforated Buccal Plate Lingual Placement Ridge Split with Surgical Bur  
Upright #31 #30 Implantation Continue Upright   #17 Immediate Implant As Upright Anchorage Extract #18 for Efficiency  
Supraerupted Opposing Tooth Magicore Cuff Enough Vertical Space   Two Molar Implants Surgical Stent Is Helpful  
#19 Large Roots Deviated Mesially     1 Year Post Ext Ideal Trajectory How to Change  
Periimplantitis-Induced Abscess Immediate Replacement (Single Drill) Periodontitis with Bruxism Explore Socket (YZW) Large Implant at #18
#19 Pointed Ridge CD Trim, 5mm cuff Place with GBR   #31 Narrow M-D Space Narrow Implant (LW) Flap Surgery  
Narrow Mesiodistal Space Proximal Reduction     #18 Wide Ridge WJM Trajectory Control Mesial Socket Placemen  
Dislodged Crown (WZG) Larger, Longer Abutment   Implants Change Class II Occlusion to Class I One Ridge Reduction HSF  
#30,31 Advanced Perio Tap Drill, Upright Narrow Implant   Bruxer, #31 Long Impl Supraerupted Shorter than Planned  
#30 Class V Furcation Involvement Spongy Bone   Place #18 implant at #17 Socket Depth Control  
#19 1 or 2 implants? 30: 3 mm Cuff #19 Dual; 30 1-Piece   #31 RPD abutment Reliable Landmark Temp Provisional  
#29 Post Socket Preservation   #30 Bone Expansion 29-31 Severe Bone Loss Long Sockets Uneven B-L Bone
#30 Thin Septum Septal Resection 6 mm Implant   #18 2nd Caries Limited Restorative Height Place Implant Deep  
#30 Long Defect Long Implant Nearly Hit Nerve   #31 DO Subgingival Caries Long Implant Calculate Implant Length  
#30 Drifting, 7mm Abutment  6 mm Cuff Sinus Master Kit   #18 Fistula after RCT with Several Canals Distortion of PAs  
#30 Low Bone Density Expansion or 1-Piece Ridge Reduction   #30 Small Diameter Implant with Premolar Width  #31 Socket Preservation  
#30 Pain Post RCT Retreat Multi-Drills; 5.5x13 Tap with Soft Tissue Mark   Lower RPD Retained by Ball Abutment at #17 Short and Quick  
#30-32 Failed FPD Magicore FC Instead   #31 Endo Failure 9 mm Implant Placement Failure  
#19 Pontic: Magicore or 1-Piece Implant Wide Ridge: Magicore   #18 Large Radiolucency Taps/Dummy/Osteotomy 8x14 mm Screw Implant 1st IBS Guide
#30 Severe Bone Loss, Bone or Tissue Level Implant 2.5 mm 1-Piece Implants   #18 Limited Vertical Height Magicore FC Placed Deeper  
#30 Buccolingual Fistulae Long Implant Depth Control   #18,19 Anchors to Upright #20 Buccolingual Plate Discrepancy Ortho
#18-20 FPD will be Sectioned Twice No Drill Osteotomy   #18 Severe Bone Loss Large Tissue-Level Implant Limited Bone Height  
#19 Lost Crown and Post IS Implant Hexed Temporary Abutment   Failed #18-20 FPD Flatten Pointed Septum Distal Socket Placement  
#30 Coronally Migrating Residual Roots Bicon Discrepancy of Buccolingual Crests   #18 Furca Large Abutment to Prevent Crown Dislodgement Socket Preservation  
30 Narrow M-D Space and Narrow Ridge Two-pointed Fixation   31 Mesial Shift, Tilt Mesial Slope Small & Short  
19 Bone Height Decreases as Residual Roots Expelled Distal Narrow Ridge   18 Sufficient Bone Height   5x11.5 mm Implant with Stability   
#19: Longest implant           Large Mesial Defect 5x15 mm Implant   31 Limited Height   4 mm Stopper  
#19 Pointed Long Ridge Bone Condensation Instead of BEB Mini 18 Indistinct IAC Surgical Guide No Risk:Lingual Plate Perforation  
#19 Bone Loss with Residual Root Formation & Exfoliation Implant Placed at Buccal Crest   30,31 Limited Vertical 1-Piece, 5 Steps Drawbacks of Free Hand Surgery  
30 Mesial Shift Mesial Socket Osteotomy Low Stability   18 Pain after Crown Possible Root Fracture Apical Periodontitis  
#30 Flattened Septum Deeper Osteotomy Shorter Implant Less Pain   31 Post Socket Preservation      
30 Pontic Food Impaction   3x10(4) mm 1-Piece   31 Guided Surgery Post Implant Removal No Tap at Grafted Site  
30 Limited Height   4.5x10 mm 2-Piece   31 Short Bone 7.3 mm Long Implant    
30 Septal Bone Regeneration       18 Post Socket Preserv   Depth Control  
19 Uneven Buccolingual Crests   Unhealed Socket   18 ML subgingival margin #15 surpraerupted C Canal  
19 Implant Prior to Ortho   Guided Surgery   19,18 Guided Surgery in Stage Quick, Painless, Depth Control  
19 Mesial Root Fracture Threads Covered by Bone Hard Bone, Short Implant   31 Immediate with 32 Ext 30 Immediate 2nd Stage Immediate Implant Longer than 30  
14,30 Guided Surgery for  Dentophobic Patient 30   18,31 Guide Opposing Intrusion Limited Clearance  
30 Temporary Abutment For Large Tissue Profile Hard Bone/Osteotomy Deviation   31 Pointed Ridge Bone Trimmer/Planning Kit Orthodontic or Restorative Intrusion  
19 Supraerupted Place Implant Deep 3 mm Above the Bone   30 (Delayed), 31 (Immediate) 1st Guide for Immediate Hard Bone  
19 Distal Placement to Upright 18 Intrude #14 Guide     14,19,31 Guided Surgery CT (#3)    
19 Pointed Short Bone 4x7.3 mm Implant     18,19,30 Implant Diameters Dense Bone    
30 Possible Crown Crack Prevent Loose Screw Thin Septum: Surgical Risk   31 Post 14,15 Implants with Opposing Supraeruption  
29/30 Fused PARL  3 M Post Socket Preserv. Immediately Postop CT   30  Immediate 31 Delayed  
19 Dense Bone Formation 2 Options of Depth Block of Handpiece   31 Long Bone (FPD)   Infiltration Anesthesia  
    Quick Turnaround for Apprehensive Patient   31 Residual Roots with Opposing Supraeruption Magicore  
14,19 Under-Prep, -Size Class I Occlusion Surgical Precision   18   Trajectory Adjustment  
30 Guide now 31 in Future       15/18 Ortho Short Implants    
29,30 FPD Removed Guide Design: Hard Bone Short and Stable   31 Distal Vertical Fracture Severe Infection    
19 Narrow Ridge IS Guide for Magicore   28 Concave 31 18      
30 Distal Root Fracture Crestal Level, 11.5 mm Most Secure Socket Preservation          
19 PRF/Implant Assisted   Setting acrylic   31 D Subgingival Caries 31/32 Ext    
19  2nd UF Guide          
19 distal root periodontal- endodontic lesion More Secure Retention          
29,30 Splint Provisional          
19 No Loose Screw Tissue level Implant            
30 Residual Roots Limited Crown Height            
30 Severe Bone Loss Provisional, Perio Dressing Guide   31 PARL Next to Nerve Extraction with Precaution    
14 19 Short Narrow              
19 Severe Bone Loss 15 mm Implant            
30 Implant Before Restoration              
30 Mesial Root Fracture Guided Immediate            
30 Narrow M-D Space       30 (Delayed), 31 (Immediate) Implants    
30 Osteoporosis Long Implant with SLA     9,31 Prevent Periimplantitis      
19 Dense Bone Formation 2 Options of Depth            
19 Improve Implant/Crown Ratio Prevent Periimplantitis     30,31 Limited Vertical 1-Piece, 5 Steps    
19 Severe Bone Loss Socket Preservation            
19 Mesial Root Fracture Threads Covered by Bone     19,30,31 Guided Surgery      
#19 Mesial Root Fracture As Lingual As Possible            
19 Distal Root Fracture Guide for Mesial Socket     12-14, 18,19 Limited Bone    
#19 Narrow M-D Space              
19 Smoker Socket Preservation Flapless Bone Expansion            
30 Mesial Root Fracture Osteotomy: Middle Socket            
#30 Pyramidal Ridge with Opposing Supraerupted     31 Depth Control in Native Bone Mesial Root Fracture    
#30,31 Narrow M-D Space 1 or 2 Implants?            
19 Bone Loss Until Septal Base       31 with Opposing Supraeruption      
#19,20 Perio Abscess after SRP     31 Mesiolingual Inclination Parallel to 1st Molar    
#30 Narrow Ridge Top Trimming            
#19 Possible Tripod Septum     Loose Proximal Contact 2 Years Post Cementation    
#19: 18 mm implant 3-Pointed Fixation     4 Q Molar Implant Reconstruction      
19 Narrow M-D Space, Tilt              
#18,19 Toothache Endo-Perio Disease     18-21 Failed FPD As Lingual As Possible    
Narrow Ridge with Low Density Wheel Saw     Endo-Perio-Malposition Splinted Provisional    
2 Lost Teeth with Reduced Space 1 or 2 Implants?     Supraeruption of Opposing Magicore Implant    
Peculiar Bone Resorption: #19, 30       ~6 mm Apical Bone Drills, Control of Depth    
FPD Failure Magicore     Advanced Periodontitis Implant Protection    
#30 Narrow Ridge 2 of 1-P Implant     Abscess from #31 or 32 XQ      
Distal Root Bone Resorption  Mesial Implantation     #18 7 mm Bone Where to Place    
#30 Moderate Ridge Flapless     #18 Root Resorption What Should be Done?    

Immediate Implant Molar Crown Materials for Bruxer

Xin Wei, DDS, PhD, MS 1st edition 01/21/2014, last revision 07/16/2019