International Journal of Periodontics & Restorative Dentistry, 04/1996

Esthetic reconstruction of large-volume Class III ridge deformities where bone and soft tissue have been lost buccolingually as well as apicocoronally continues to offer a major challenge in therapy to periodontists and to those engaged in advanced reconstructive dentistry. No single procedure is well suited for solving all problems in reconstructive surgery. A series of staged surgical procedures is frequently necessary to augment the ridge to its former dimensions. The authors have devised a combination onlay-interpositional graft procedure that appears to offer promise in solving many of the problems encountered in gaining predictable soft tissue ridge augmentation in Class III ridge defects.

Implant diagnostic methods using computed tomography with barium-coated templates have revealed the relationship between the optimal final tooth position and the residual alveolar process or ridge. While information with regard to emergence axis, anatomic limitations, fixture length, buccolingual cantilever, and prediction of the final prosthetic design is available, presurgical information relating to the reconstruction potential of smile zone deformities remains elusive. The use of a complete provisional wax-up and the modification of a barium-coated template design can provide the implant team with presurgical information regarding the need for augmentation of hard tissue and soft tissue and the volume of tissue needed for reconstruction. This information can assist the implant team in the development of realistic treatment objectives and in more accurately addressing the needs and concerns of the patient during presurgical treatment planning.

As a result of a fracture to the cemented post and core, a pure titanium implant was extracted from a 54-year-old patient after 4 years of clinical loading. At implantation, the implant was positioned into an extraction socket and the defect was treated with an e-PTFE membrane associated with a DFDBA graft. At retrieval the implant underwent histologic and histochemical examination to assess the characteristics of the regenerated bone after 4 years of prosthetic loading. The implant showed an angular bony defect at the smooth collar, but the bone-implant dierct contact rate seemed to be elevated in the remaining implant surface. Normal transmitted and polarized light examinations demonstrated that most of the DFDBA particles were resorbed and substituted by vital newly formed bone. The regenerated bone appeared compact with secondary osteons and large haversian canals; however, some partially mineralized remnants residuated in the spaces between the osteons. Within the limits of this study, the authors concluded that DFDBA can be substituted by the host bone, but the rate of substitution is very slow and not complete after 4 years. From a clinical point of view, however, the load-bearing capacity of the bone regenerated with the membrane technique associated with DFDBA appeared to be similar to that of normal bone.

This article describes a grafting technique using connective tissue to perdictably obtain primary closure of extraction sockets treated with an osteopromotive membrane technique. This technique was used for a total of 24 sites in 22 consecutive patients to regenerate alveolar bone in severely damaged ridges and in conjunction with implants immediately installed into extraction sites. Two sites (8.3%) were complicated by premature membrane exposure that necessitated early removal. In the remaining 22 sites, membranes remained completely covered for a mean period of 23.75 weeks (SD = 8.21 weeks; range = 10 to 38 weeks).

A surgical technique to achieve root coverage in buccal gingival recessions by means of expanded polytetrafluoroethylene membranes in combination with miniscrews is presented. After raising a trapezoidal split flap, supporting screws were used to create a large space underneath the membrane, while head screwswere employed for perfect stabilization of the Teflon barrier. Intramarrow perforations were made to induce the rapid formation of a large blood clot with abundant availability of progenitor cells. The membrane and the miniscrews were removed after 3 or 4 weeks. The treatment of 12 cases, with mucogingival defects 4 to 7 mm deep, resulted in a mean root coverage of 84%.

Attempts to save natural teeth have created numerous restorative, endodontic, and periodontal techniques. It has always been considered the treatment of choice to save teeth whenever possible, and extreme efforts to save teeth are often considered because of the poor treatment alternatives for replacing them. Today osseointegration provides a predictable means of replacing teeth; therefore, retaining questionable teeth may not be as necessary as in the past. This article reviews situations in which the selective extraction of compromised natural teeth or even healthy natural teeth is considered because of alternative treatment options utilizing osseointegrated implants.

This study reports the clinical outcomes obtained in a longitudinal cohort of 23 patients treated by guided tissue regeneration for strategically important teeth compromised by the presence of deep intrabony defects. After completion of initial periodontal therapy and placement of a provisional fixed partial denture, a nonresorbable e-PTFE membrane was applied to isolate the defect. Changes in probing attachment level, probing pocket depths, and radiographic bone support were evaluated 12 months after removal of the membrane. Clinically and statistically significant improvements in outcome measurements were observed: a probing attachment level gain of 5.3 ± 1.7 mm, a reduction in probing pocket depths of 6.1 ± 2 mm, and an increase in the percentage of radiographic bone support of 31% ± 18%. The results obtained were highly reproducible with 91.3% of the cases resulting in probing attachment level gains of 4 mm or more. The evidence provided in this investigation indicates that guided tissue regeneration can predictably increase the functional support, and possible improve the prognosis of strategically important abutments. Guided tissue regeneration therapy should, therefore, be one of the options discussed in treatment planning for complex periodontal-prosthetic cases.

Esthetic considerations pose therapeutic dilemmas in the selection of surgical techniques in anterior periodontal surgery. Two surgical techniques designed to maximize postoperative esthetics in the anterior regions are described. Changes in interdental papillary height are reported and compared at 1 year postoperative. This study discusses the surgical techniques, their advantages and disadvantages, and their indications. Since there is less risk of recession and more potential for gain in papillary height, the papillary retention procedure, when possible, may be the procedure of choice in anterior regions.