title: A new approach to rehabilitate the severely atrophic maxilla using extramaxillary anchored implants in immediate function: a pilot study.
abstract: BACKGROUND
  There is a need to simplify implant treatment for complete arch rehabilitation of severely atrophic maxillae, as well as a desire to eliminate grafting and provide quality rehabilitation in terms of esthetics, function, and comfort for the patient.
  
  
  OBJECTIVE
  The purpose of this study was to report on the initial results of rehabilitation of complete edentulous atrophied maxillae using a new surgical approach and a newly designed extra long implant, placed externally to the maxillary bone (implant only accommodated in the maxillary bone) and anchored in the zygomatic bone.
  
  
  METHODS
  The pilot study included 29 patients (21 women and 8 men), with an age range of 32-75 years (mean=52.4 years), followed between 6 and 18 months, with a mean follow-up time of 1 year. The patients presenting severe atrophy in the maxillae (Cawood and Howell classification C-VI and D-V or D-VI) were rehabilitated either by using 1, 2, or 4 extra long implants (30 to 50 mm in length; Nobel Biocare AB) placed in the zygomatic bone in conjunction with standard implants (24 patients): or 4 extra long implants (5 patients), all placed in immediate function. The criteria used to evaluate implant outcome were: implants function as support for reconstruction; implants stable when individually and manually tested; no signs of infection observed; and good esthetic outcome of the rehabilitation. To evaluate the secondary objective of assessing the stability and health of the soft tissue covering the implants, the mucosal seal efficacy evaluation index (MSEE) was used. This index was modified from the probing depth for standard implants and performed with a 0.25-N calibrated plastic periodontal probe measuring the depth (mm) of the space between the implant and the mucosa. Data were analyzed with descriptive and inferential analyses.
  
  
  RESULTS
  The cumulative implant survival rate and prosthetic survival rate at 1 year were 98.5% and 100%, respectively. The mean and median values of the MSEE at 2 months (2.9 mm, 3 mm), 4 months (2.5 mm, 2.8 mm), 6 months (2.9 mm, 2.8 mm), and 1 year (2.8 mm, 2.5 mm) are comparable to the values of probing depths assessed for standard implants.
  
  
  CONCLUSIONS
  The results indicate that, within the limitations of this preliminary study, the rehabilitation of maxillae with severe atrophy can be performed using extra long implants placed external to the maxilla and anchored only in the zygomatic bone, and placed in immediate function.
authors.affiliation: Private practice, Lisbon, Portugal.
authors.forename: Paulo
authors.initials: P
authors.lastname: Maló
authors.forename: Miguel de Araujo
authors.initials: Mde A
authors.lastname: Nobre
authors.forename: Isabel
authors.initials: I
authors.lastname: Lopes
mesh_terms: D000328:Adult; D000368:Aged; D016301:Alveolar Bone Loss / Q000534:rehabilitation*; D003758:Dental Implantation, Endosseous / Q000379:methods*; D015921:Dental Implants; D017267:Dental Prosthesis Design; D019094:Dental Prosthesis, Implant-Supported; D005260:Female; D006801:Humans; D007575:Jaw, Edentulous / Q000534:rehabilitation; D008297:Male; D008439:Maxillary Diseases / Q000534:rehabilitation*; D008875:Middle Aged; D010865:Pilot Projects; D013997:Time Factors; D015050:Zygoma / Q000601:surgery*
chemical_list: D015921:Dental Implants