title: Periapical surgery in maxillary premolars and molars: analysis in terms of the distance between the lesion and the maxillary sinus.
abstract: OBJECTIVE
  This study compares periapical surgery (PS) of the maxillary premolars and molars in close proximity to the maxillary sinus with those not in close proximity, and assesses postoperative morbidity and prognosis.
  
  
  METHODS
  A prospective follow-up study was carried out on clinical cases of PS using the ultrasound technique. Only patients undergoing PS in maxillary premolars and molars were included in this study; minimum follow-up was set at 12 months. The cases were classified into 2 different groups in function of the proximity of the periapical lesion to the maxillary sinus: group 1, when the distance was less than 2 mm; group 2, when the distance was greater than or equal to 2 mm. Postoperative morbidity was measured, as well as a clinical and radiographic follow-up evaluating the overall mid- and long-term success rate using von Arx and Kurt criteria. SPSS 12 was used for the statistical analysis. All measures of estimated association were then tested for statistical significance, and declared significant for P less than .05.
  
  
  RESULTS
  PS was carried out on 92 patients, 106 teeth, and 129 periapical lesions. Group 1 was composed of 43 maxillary premolars and molars with 59 lesions, and group 2 of 63 teeth and 70 lesions. Maximum pain occurred during the first 6 hours and swelling reached its peak on the second day. The overall healing in maxillary premolars and molars was 75% success, 10% improvement, and 15% failure at 1-year follow-up. There were no significant differences between the 2 groups regarding postoperative pain, swelling, and outcome (P > .05).
  
  
  CONCLUSIONS
  The success of PS in maxillary premolars and molars at 12 months follow-up was 75%. Failure rates in premolars and molars in close proximity to the maxillary sinus were higher than unrelated premolars and molars, but the differences were not significant statistically.
authors.affiliation: University Medical and Dental School, Valencia, Spain.
authors.forename: Berta
authors.initials: B
authors.lastname: Garcia
authors.forename: Miguel
authors.initials: M
authors.lastname: Penarrocha
authors.forename: Eva
authors.initials: E
authors.lastname: Martí
authors.forename: José María
authors.initials: JM
authors.lastname: Martínez
authors.forename: Cosme
authors.initials: C
authors.lastname: Gay-Escoda
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000541:Alveolectomy / Q000379:methods*; D000704:Analysis of Variance; D001641:Bicuspid / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008437:Maxilla / Q000601:surgery*; D008443:Maxillary Sinus / Q000033:anatomy & histology*; D008875:Middle Aged; D008963:Molar / Q000601:surgery; D010483:Periapical Diseases / Q000601:surgery*; D011446:Prospective Studies; D011862:Radiography, Panoramic; D012184:Retrograde Obturation; D018709:Statistics, Nonparametric; D019227:Tooth Apex / Q000033:anatomy & histology*; D014465:Ultrasonics