1. How successful are dental Implants? A personal series of 1000 implants Mr Bill Smith Consultant Oral and Maxillofacial Surgeon Woodland Hospital, Kettering & Three Shires Hospital, Northampton

2. Method  Retrospective study  Data analysed from custom database  Query analysis from Microsoft Access  Age  Frequency of procedure  Implant site  Augmentation  Site of augmentation  Failure  Analysis of failure

3. Demographics Total number of implants/fixtures = 1000 Total number of patients = 490 Most implants(80%) placed between 40 to 69 years of age Number Of implants 86% of patients are non smokers: smoking increases failure of implants both short and long term

4. Demographics 71% of implants placed at Woodland Hospital, Kettering. 23% placed at Three Shires Hospital,Northampton.

5. Implant patients 50% of all patients receive 1 implant, 28% receive 2 implants.

6. Position of implants Upper/Maxillary implants The Incisor region is the commonest site(52%) in the maxilla(upper jaw) totals

7. Position of Implants Lower jaw /mandibular implants The Molar region is the commonest site (27%) in the lower jaw c.f upper jaw

8. Augmentation – Bone grafts Autograft:(human to human) bone Chin : N = 11 Posterior mandible : N = 26 Iliac crest(hip): N = 25 TOTAL Autograft = 62 patients Xenograft bone(animal to human) Total BIO-OSS =50 patients Total Grafts (1997 -2013) N = 113 patients Socket augmentation N = 41 Onlay grafts N = 48 Sinus lift procedures – unilateral and bilateral N = 34

9. Site of Bone Augmentation UPPER JAW(Maxilla) LOWER JAW(Mandible)

10. Bone Augmentation Summary Patients own bone now superseded by manufactured Xenografts - BIO-OSS very successful (1% failure) 112 of 490 patients (23% patients) need an augmentation/bone graft of some type Augmentation needed in 263 sites for 1000 implants (26% of all implants) Augmentation much more common in Upper Jaw(89%) than Lower Jaw(11%) Variety of techniques needed 37% of grafts needed in mandibular molar region to maximize bone for implant so reducing risk of Inferior Dental nerve injury.

11. Failure of implants 15(3%) of 490 patients identified with failed implant(s) Dental Status: 11 patients are DENTATE, 4 patients edentulous. Radiotherapy to Implant site: 8 of 15 patients received radiotherapy to bone PRIOR to implant placement. 20 (2%) fixtures identified as failure – complete loss 13(1.3%) fixtures lost in non-irradiated cases 12(80%) patients with failure identified with previous/pre-existing periodontal disease All patients were non smokers Average time from insertion to failure in 20 fixtures is 27 months(range 3 weeks to 9 years 6 months)

12. Failure by site Implant failure Failure by site Site Total failed fixtures Total fixtures Percentage failure Upper Anterior(canine- incisor) 84731.7% Upper Posterior(premolar – molar) 62412.5% Lower Anterior(canine – incisor) 51044.8% Lower Posterior(premolar- molar) 11820.5% TOTAL201000

13. Injury to the Inferior dental Nerve Number of implants inserted in the lower second premolar –molar region = 132 Number of Inferior dental nerves injured = 3 Risk of nerve damage per implant = 3/132 =2.2%

14. Summary Upper incisor - commonest implant site Upper incisor - commonest implant site 23% of implants preceded by a bone augmentation procedure 23% of implants preceded by a bone augmentation procedure Bio-Oss very successful and superseeds autografting techniques Bio-Oss very successful and superseeds autografting techniques Overall implant failure is 2% Overall implant failure is 2% Failure in normal/non radiotherapy cases is 1.3% Failure in normal/non radiotherapy cases is 1.3% 80% of failures associated with previous or pre- existing periodontal disease 80% of failures associated with previous or pre- existing periodontal disease Injury to the inferior dental nerve in posterior mandibular implants is 2.2% Injury to the inferior dental nerve in posterior mandibular implants is 2.2%