Pages 207-219, Language: English
Thirty-two consecutively treated patients were included in this study of 49 root-resected molars that were under regular recall of 3 to 6 months for a mean of 11.5 years (2 to 23 years). Treatment modalities for all patients were very similar. Endodontic treatment was conservatively performed prior to resection with maximum preservation of tooth structure. No threaded posts were used. Provisional restorations were in place prior to periodontal therapy (pocket reduction with or without osseous surgery). Most patients were treated with complete-mouth reconstructions. Ninety-two percent of all resected molars survived an average of 12 years. Teeth failed because of recurrent caries or for endodontic and strategic reasons. If proper treatment is rendered, periodontically involved molars can be maintained for a long period of time and serve successfully as abutments in complete-mouth restorations. Great care must be taken throughout the whole process of case selection, reevaluation, and endodontic, periodontal, restorative, and maintenance therapies.
Pages 221-230, Language: English
The aim of this study is to show the possibility of achieving more than a 4-mm new vertical bone apposition on partially edentu lous patients were treated from July 1993 to September 1993. After accurate radiographic investigation, all of the patients were treated using the Branemark System. After insertion, 14 fixtures were left circumferentially exposed for 37 mm. Autogenous bone graft harvested from a bone filter was placed around the exposed threads and completely covered with titanium-reinforced Gore-Tex augmentation membranes (TR-GTAM). Flaps were coronally displaced to passively cover the regenerative materials. Only one of the six membranes was exposed and it was removed immediately. After a 12-month healing period, the membranes were removed in conjunction with the second-stage surgical procedure. In the five cases where the membranes were kept covered, all of the available space underneath the TR-GTAM was filled with regenerative tissue. In all of the cases a histologic biopsy was performed. In one case all the space was filled with more than 7 mm of bone. In three cases all the space was filled with more than 5 mm of bone. In one case the most coronal part (approximately 1 mm) of the regenerative tissue was represn=e ted by connective tissue; the remaining tissue was represented by bone. The measurements demonstrated an average of vertical ridge augmentation of 4.95 mm. In the only case where the membrane underwent exposre and was then removed there was no regenerative tissue present.
Pages 231-240, Language: English
Esthetic dentistry comprises one of the most rapidly growing segments of our profession, and patients receiving this type of treatment are often maintained on an alternating schedule. Improper maintenance care can quickly destroy many of these restorations. This article will serve as a resource for dental professionals who wish to offer these special patients customized maintenance care.
Pages 241-252, Language: English
Class V cavities with mechanical exposures were prepared in 178 teeth of seven monkeys to observe the temporal healing of exposed pulps in direct contact with various dental materials, with or without a biologic seal of zinc-oxide eugenol cement against microleakage. Thirty pulps were direct capped as calcium hydroxide controls. The remaining 148 exposures were direct capped, 41 with silicate, 39 with zinc phosphate, 33 with amalgam, and 35 with an auto-cured composite. Sixty-four were restored to their cavosurface margin with their respective material and 84 were sealed to the cavosurface margin with zinc-oxide eugenol cement. Tissues were obtained by perfusion fixation at intervals of 35, 21, 14, 10, 5, and 3 days, and then processed and evaluated. The results of this tudy demonstrated that exposed dental pulps possess an inherent healing capacity, allowing cell reorganization and dentin bridge formation when adequately sealed with zinc-oxide eugenol cement to prevent bacterial microleakage.
Pages 253-266, Language: English
The supposition that staggered buccal and lingual implant offset is biomechanically advantageous was examined mathematically. The method of evaluation utilized a standard hypothetical geometric configuration from which implants could be staggered buccally and/or lingually in both arches. Torque (moment) values were calculated at the gold screw, abutment screw, and 3.5 mm apical to the head of the implant. Comparisons were made in percentages of change from the hypothetical standard to the buccal and/or lingual implant offset. In the maxillary arch, buccal offset decreased the torque (moment) while lingual offset increased it. If more lingually offset implants were present in the maxillary restoration, the total torque would be greater than if they were all in a straight line. Staggered buccolingual implant alignment often requires abutment reangulation. The resultant line of force produced by occlusal anatomy usually results in buccal inclination in the maxillary arch and lingual inclination in the mandibular arch. As a result, mandibular implant/prostheses are greatly favored over similar maxillary configurations because the mandibular resultant line of force usually passes lingually, closer to the components and supporting bone and considerably less torque is produced. Therefore, the concept of staggered offset for multiple implant-supported prostheses can be utilized on the mandible but is not recommended for the maxilla where maximum uniform buccal implant orientation is advised.
Pages 267-278, Language: English
Various grafting procedures have been developed for reconstruction of partially edentulous ridge deformities prior to prosthetic rehabilitation. The majority of these procedures have been applicable to reconstruction of Type I (buccolingual) ridge deformities. Type II and Type III defects present a more difficult challenge because of the need for apicocoronal augmentation and replacement of greater volumes of lost tissue. The only and subepithelial connective tissue grafts have been predominately used for the treatment of these type of defects, however, each procedure presents certain limitations. This report describes a simple modification of the connective tissue graft that enhances its ability to augment tissue for Type II and Type III deformities. The technique is an effective and predictable procedure for advanced ridge deformities.
Pages 279-289, Language: English
Because the existence of cylosportin A-induced gingival overgrowth in animals has not been well established, a pilot study was undertaken to determine whether such gingival overgrowth could be observed in Sprague-Dawley rats. Thirty-six male rats, age 6 weeks, were randomly divided into two groups. The test group was given 30 mg/kg of body weight of cyclosporin A daily by gastric feeding. The control group was given mineral oil instead. Stone casts of the gingiva in the mandibular incisor region were made biweekly for 6 weeks. The three-dimensional growth pattern - the buccolingual width, the mesiodistal width, and the vertical height of the gingiva - was analyzed on the casts. The animals were killed after the last impression was taken, and tissue sections were made. Stereomicroscopy revealed marked overgrowth of the gingiva in the test rats. All three-dimensional measurements on the stone casts were greater in the test group, beginning 2 weeks after cyclosporin A was given. Histologically the overgrowth of the epithelia and connective tissue was easily confirmed in the buccal and lingual gingiva of the test rats.