Determining the localization of premolar zenith positions according to the gingival line.

BACKGROUND: The gingival zenith (GZ) positions according to a reference line in the premolar (PM) area remain concern, especially for the clinicians in placing the gingival contours during surgery. OBJECTIVES: The objectives of this study are to determine the maxillary PM GZ positions according to GZ line (GZL). MATERIALS AND METHODS: A sample population of 63 patients with healthy gingival tissue was studied. The GZ was determined at the most apical point of the gingival marginal scallop. A horizontal-zenith line (ZL) was drawn connecting the GZ from the ipsilateral canine (C) and central incisor teeth. Reference lines were drawn, and bilateral measurements were taken in the respective stone casts in the PM area. RESULTS: No statistically significant differences were found between bilateral first premolars (FPM) and second premolars (SPM). When considering ipsilateral FPM and SPM, statistically significant differences were found between them. For all PM teeth, the mean distance value of GZ to GZL was approximately 1.32 mm. CONCLUSIONS: The present study results showed that GZs of FPM and SPM teeth for both left and right sight was coronally located according to ZL.

Oral rehabilitation with endosseous implants in a child with ectodermal dysplasia: a case report.

AIM: The purpose of this article is to report the clinical course of a 12-year-old child with ectodermal dysplasia who was treated with an implant-supported overdenture for the mandible and an overdenture for the maxilla. CASE REPORT: Two dental implants were placed in the canine regions of the mandible. The maxillary teeth were prepared for the milled copings. Because the preparation of parallel walls was difficult, near-parallelism with an angle of convergence or taper of approximately 5 degrees was achieved. The cervical third of the teeth was prepared to be as parallel as possible to one another. In addition, the occlusal surfaces were reduced 1.5 mm, and the axial surfaces were reduced 1 mm. Occlusal reduction was performed to provide adequate thickness for the overlying denture base material. A chamfer finish line was prepared. The copings were cast with a Cr-Ni-based metal alloy and luted, bilateral balanced occlusion was developed using anatomic acrylic teeth. An impression was taken with an individual tray for impressions of overdentures. In response to the patient's dry mucosa, the impressions were taken using rapid-setting silicone impression material with high elasticity. Bilateral balanced occlusion was achieved using anatomic acrylic teeth for overdentures. The maxillary overdenture and implant-supported mandibular overdenture were prepared by conventional methods using thermal-curing acrylic resin. The patient was seen 48 hours later for adjustment, then after 1 and 2 weeks, 1, 3, and 6 months, and 1 year and he is still satisfied with his prosthesis both aesthetically and functionally. CONCLUSION: The use of endosseous implants in the prosthetic rehabilitation of children with ectodermal dysplasia may provide a considerable improvement in comparison with traditional prosthetic methods.

The evaluation of vertical heights of maxillary and mandibular bones and the location of anatomic landmarks in panoramic radiographs of edentulous patients for implant dentistry.

The purpose of this study was to determine variations in the vertical height measurements in the edentulous maxilla and mandible, and to assess positions of the maxillary sinus, mandibular foramen, and the mandibular canal, which are important for implant length selection and planning using panoramic radiographs. The study sample included 346 edentulous alveolar ridges of 90 men and 83 women. Sixty-three dentate patients' panoramic radiographs were used for location of the first premolar and molar area. Panoramic radiographs were made with a Siemens Orthophos panoramic machine which had been standardized previously. All radiographs were made using a standardized manner by the same technician. Fourteen sites were measured on every panoramic radiograph whenever possible, eight sites in the maxilla and six sites in the mandible. Correlation analyses were performed between age groups and all measurements to determine if age is significant as a covariate. In order to examine the effect of gender the statistical analysis of differences between men and women was performed with Student t-test. The 5% significance level was used for statistical significancy. The height of the maxilla and the mandible in the anterior, first premolar, and first molar regions were significantly greater in men than in women. A majority of the most inferior border of the maxillary sinuses was located anterior to the first molar area (premolar regions) both in men (48.9%) and women (55.4%). Although, there was no statistically significant difference between edentulous men and women for the vertical distances from the mental foramen to the alveolar crest, and horizontal distances from mental foramen to midline, there were statistically significant differences between edentulous men and edentulous women for the vertical distances from the upper border of the mandibular canal to the alveolar crest in the first molar area. Mental foramens were located at the crest of the ridge in 7.2% of the edentulous women, and 6.7% of the edentulous men. The results of this study may guide clinicians to make primer decision of implant insertion area for implant supported prosthesis in edentulous patients.