Basic Surgical Techniques for Endosseous Implant Placement Division of Oral and Maxillofacial Surgery University of Minnesota

 Dental implant is an artificial titanium fixture which is placed surgically into the jaw bone to substitute for a missing tooth and its root(s). WHAT IS A DENTAL IMPLANT?

In 1952, Professor Per-Ingvar Branemark, a Swedish surgeon, while conducting research into the healing patterns of bone tissue, accidentally discovered that when pure titanium comes into direct contact with the living bone tissue, the two literally grow together to form a permanent biological adhesion. He named this phenomenon "osseointegration". History of Dental Implants

All current implant designs are modifications of this initial design First Implant Design by Branemark

STEP 1: INITIAL SURGERY STEP 2: OSSEOINTEGRATION PERIOD STEP 3: ABUTMENT CONNECTION STEP 4: FINAL PROSTHETIC RESTORATION Surgical Procedure

Fibro-osseous integration Fibroosseous integration – “tissue to implant contact with dense collagenous tissue between the implant and bone” Seen in earlier implant systems. Initially good success rates but extremely poor long term success. Considered a “failure” by todays standards

Osseointegration Success Rates >90% Histologic definition –“direct connection between living bone and load- bearing endosseous implants at the light microscopic level.” 4 factors that influence: Biocompatible material Implant adapted to prepared site Atraumatic surgery Undisturbed healing phase

Soft-tissue to implant interface Successful implants have an –Unbroken, perimucosal seal between the soft tissue and the implant abutment surface. Connect similarly to natural teeth-some differences. –Epithelium attaches to surface of titanium much like a natural tooth through a basal lamina and the formation of hemidesmosomes.

Soft-tissue to implant interface Connection differs at the connective tissue level. Natural tooth Sharpies fibers extent from the bundle bone of the lamina dura and insert into the cementum of the tooth root surface Implant: No Cementum or Fiber insertion. Hence the Epithelial surface attachment is IMPORTANT

Subperiosteal

Transmandibular Implant

Blade Implant

Endosteal Implants

The “Parts” Implant body-fixture Abutment (gingival/temporary healing vs. final) Prosthetics

Clinical Components

abutment

Team Approach A surgical – prosthodontic consultation is done prior to implant placement to address: –soft-tissue management –surgical sequence –healing time –need for ridge and soft-tissue augmentation

Clinical Assessment Assess the CC and Expectations Review all restorative options: –Risks and Benefits Select option that meets functional and esthetic requirements

Patient Evaluation Medical history –vascular disease –immunodeficiency –diabetes mellitus –tobacco use –bisphosphonate use

History of Implant Site Factors regarding loss of tooth being replaced –When? –How? –Why? Factors that may affect hard and soft tissues: –Traumatic injuries –Failed endodontic procedures –Periodontal disease Clinical exam may identify ridge deficiencies

Surgical Phase- Treatment Planning Evaluation of Implant Site Radiographic Evaluation Bone Height, Bone Width and Anatomic considerations

Basic Principles Soft/ hard tissue graft bed Existing occlusion/ dentition Simultaneous vs. delayed reconstruction

Smile Line One of the most influencing factors of any prosthodontic restoration If no gingival shows then the soft tissue quality, quantity and contours are less important Patient counseling on treatment expectations is critical

Anatomic Considerations Ridge relationship Attached tissue Interarch clearance Inferior alveolar nerve Maxillary sinus Floor of nose

Radiological/Imaging Studies Periapical radiographs Panoramic radiograph Site specific tomograms CAT scan (Denta-scan, cone beam CT)

Width of Space and Diameter of Implant Attention must be paid to both the coronal and interradicular spaces

A case against routine CT Expense Time consuming process Use of radiographic template/proper fit requires DDS present Contemporary panoramic units have tomographic capabilities Usually adds no additional data over standard database

Image Distortion

Anatomic Limitations Buccal Plate0.5mm Lingual Plate1.0 mm Maxillary Sinus1.0 mm Nasal Cavity1.0mm Incisive canalAvoid Interimplant distance1-1.5mm Inferior alveolar canal2.0mm Mental nerve5mm from foramen Inferior border1 mm Adjacent to natural tooth0.5mm

Dental Implant Surgery Phase I Aseptic technique Minimal heat generation –slow sharp drills –internal irrigation? –external cooling

Dental Implant Surgery Phase I Adequate time for integration Adequate recipient site –soft tissue –bone Kind & Gentle technique

1. Chlorhexidine 2. Analgesics +/- antibiotics Disposition

Implant placement 3 months after menton bone grafting

Exposure of Implant during Placement

Summer’s Osteotomes

Limitations to Implant placement in the Maxilla Ridge width Ridge height Bone quality

Surgical Solutions to Anatomical Limitations Onlay Bone Graft Sinus Lift

Summers, RB. A New concept in Maxillary Implant Surgery: The Osteotome technique. Compendium. 15(2): 152, Ridge expansion technique –3-4 mm of crestal alveolar width required Sinus floor elevation technique –8-9 mm of alveolar bone height required in order to place a 13 mm implant (4-5 mm sinus floor elevation)

Introduction Ridge expansion technique 1.6 mm pilot hole Summers osteotome # 1-4 –sequenced tapered osteotomes. –ridge expansion (displacement) versus bone removal. Final drill coincident with the final implant size (sometimes not necessary)

Introduction Sinus floor elevation technique 1.6 mm pilot hole Summers osteotome # 1-4 –Sinus floor microfractured superiorly –Sinus floor can be elevated 4-5 mm –May backfill with bone allograft/alloplast Final drill coincident with final implant size

Surgical Technique

A. Rake, K. Andreasen, S. Rake, J. Swift A Retrospective Analysis of Osteointegration in the Maxilla Utilizing an Osteotome Technique versus a Sequential Drilling Technique, 1999 AAOMS Abstract 155 maxillary implants in 84 patients restored for at least 6 months –57 were placed utilizing the osteotome technique –98 were placed utilizing the drilling technique One implant failed of the 98 in the drill group None of the implants had failed of the 57 in the osteotome group

Stage II Surgery Preoperative Considerations 3-6 months after stage I

Stage II Surgery Preoperative Considerations Done under local anesthesia Pre-op medications –Chlorhexidine rinse

Placement of healing abutment

The failing implant is very difficult to treat Traumatic surgical manipulation with initial instability of implant increases risk of failure Implant success is only as good as the prosthodontic reconstruction conclusions