International Journal of Periodontics & Restorative Dentistry, 06/2008

The loss of interdental papillae as the result of trauma or inflammatory periodontal disease creates a significant challenge in the esthetic zone. Conventional surgical techniques are unpredictable because of small working spaces and limited blood supply to the area. Vertical releasing incisions can further jeopardize vascular channels and leave unattractive scarring upon healing. The application of microscopes and microsurgical instruments presents a new frontier for predictable esthetic results. This paper describes a predictable microsurgical technique for reconstruction of the interdental papillae.

Platform switching is a concept recently introduced in implant dentistry. It is intended to reduce the crestal bone loss that is commonly found around implants exposed to the oral environment. The aim of this study was to examine biopsy specimens to help explain the biologic processes occurring around a platformswitched implant. A mandibular implant was removed 2 months after placement because of prosthetic rehabilitation difficulties. The implant was then sectioned and subjected to histologic and histomorphometric analysis. An inflammatory connective tissue infiltrate was localized over the entire surface of the implant platform and approximately 0.35 mm coronal to the implant-abutment junction, along the healing abutment. A possible reason for bone preservation around a platformswitched implant may lie in the inward shift of the inflammatory connective tissue zone at the implant-abutment junction, which reduces its injurious effect on the alveolar bone.

In this consecutive series, 14 patients with severe intrabony defects and pathologic tooth migration were treated with guided tissue regeneration (GTR) and subsequent orthodontic therapy in an attempt to evaluate the validity of this multidisciplinary approach. Probing pocket depths (PPD), clinical attachment levels (CAL), and gingival recessions were assessed at baseline, 1 year after GTR, and at the end of orthodontic therapy. Radiographs were obtained at all time points. Esthetic parameters were recorded with the papilla presence index (PPI). Statistical analyses were carried out to compare the data at each time point. From baseline to 1 year after GTR, the mean PPD reduction was 5.57 mm, with a residual mean PPD of 2.71 mm; mean CAL gain was 5.86 mm. Both differences were statistically significant. There were no statistically significant differences between 1 year after GTR and the end of orthodontic therapy (mean PPD reduction 0.07 mm; mean CAL gain 0.43 mm). The reduction in PPI reflected the enhancement of papilla height that was observed in 9 of the 14 patients. Within the limits of this research, this study affirms the possibility of a combined orthodontic-periodontal approach that prevents damaging the regenerated periodontal apparatus and produces esthetic improvements as a result of realignments and enhancement of papilla height

The antral sinus bone graft has become one of the most predictable and commonly used surgical procedures to augment bone in the posterior maxilla and thereby accommodate implant placement. Positioning the lateral wall during this technique has traditionally been an intuitive process, whereby the surgeon relies on mental navigation to achieve proper identification. The purpose of this article is to introduce a prototype cutting guide that is developed through the use of computerized tomographic imaging, computer software, and the stereolithographic process to precisely position the lateral wall and facilitate Schneiderian membrane elevation. This prototype cutting guide marks the beginning of applications for "guided bone grafting" and associated techniques that focus on enhanced precision and accuracy in bone regeneration surgery.

The subepithelial connective tissue graft (SECTG) is a favorite surgical technique for the treatment of mucogingival defects. However, complete root coverage of Miller Class I and II defects is often not achieved with this procedure, especially when the defects are deep or wide. The purpose of this report is to describe a surgical technique used to manage such mucogingival defects. The technique uses a uniquely obtained SECTG with "embossed epithelium" that is designed to fit the defect site. This is employed to prolong protection of the underlying healing process. In addition, this technique avoids flap advancement, thereby allowing for the development of a wider zone of attached gingiva at the treatment site.

Four partially edentulous patients received particulate autogenous bone and platelet-rich plasma (PRP) in one sinus and particulate autogenous bone alone in the contralateral sinus. After 6 months of healing, two or three Osseotite implants were inserted, and an additional Osseotite mini-implant was placed into the graft through the lateral wall of the sinus. At abutment connection, the mini-implants were retrieved for histologic examination. Despite similar clinical and radiographic healing patterns, a higher bone-to-implant contact rate was observed on the implants placed in bone and PRP than on those placed in bone only (46.75% ± 13.6% versus 20.5% ± 5.57%, respectively).

The aim of this study was to compare the prosthetic outcomes of implant/toothsupported three-unit fixed partial dentures (FPDs) with those of freestanding implant-supported FPDs after 2 years of function. Twenty-nine partially edentulous patients presenting with unilateral or bilateral distal-extension edentulous areas received FPDs and were followed for a minimum of 24 months. In all, 49 FPDs were fabricated. In 34 FPDs, implants were connected to teeth and thus the FPDs were categorized as mixed (m-FPDs), whereas 15 FPDs were supported by freestanding terminal implants (fs-FPDs). Evaluation of prosthetic parameters including mechanical complications was performed. Changes in marginal bone level (ΔMBL) around implants in both treatment groups were measured on digitalized periapical radiographs. Neither loss of osseointegration of an implant nor intrusion of abutment teeth was recorded. All FPDs were functioning after 24 months. Mean ΔMBLs of posterior implants supporting m-FPDs and fs-FPDs at 24 months were 0.189 mm and -0.285 mm, respectively, representing a significant difference (P .05). Mean ΔMBLs at the mesial and distal surfaces of anterior and posterior implants supporting fs-FPDs were similar (P > .05). In the treatment of short-span distal-extension edentulous areas, similar clinical outcomes may be obtained for implant- and tooth/implant-supported three-unit FPDs in the early stages of function.

The present investigation was performed to compare the biocompatibility, safety, and manageability of a newly developed bone block and a deproteinized bovine bone block (Bio-Oss) for the treatment of localized bone defects in a dog model. Two male beagle dogs were used for this study. The mandibular premolars were extracted and two saddle-type defects were created bilaterally in the edentulous area. The defects were filled according to a randomized design with Bio-Oss bone block or with an equine hydroxyapatite plus collagen bone block (eHAC). Most control and test sites developed dehiscences during healing. After 4 weeks, the animals were euthanized and each hemimandible was prepared for histologic examination. No significant difference in terms of local tolerance was observed between test and control sites, and test and control sites showed similar histologic findings. However, a significant difference was noticed between the Bio-Oss block and the new bone block in terms of manageability.

Traditionally, missing and hopeless teeth have been replaced by threaded cylindric implants. Implant manufacturers have tried to design implants that more closely resemble tooth anatomy, but the neck and abutment connection areas have not changed much in the past 30 years. Some companies have produced titanium implants with scalloped contours, but the clinical application of this remains uncertain. The combination of anatomically oriented implant designs, newer biomaterials such as zirconia ceramics, and modified surfaces has resulted in dental implants that can be specially designed for the replacement of individual teeth in both arches. Ovoid zirconia implants have been specially developed and produced to replace missing or hopeless premolars. This article discusses the treatment of a patient with an ovoid zirconia implant (CeraRoot Type 14) to replace a premolar.

This case report describes a technique that uses a palatal mucosal graft and an acrylic resin postoperative stent in an attempt to increase the layer of keratinized tissue around osseointegrated implants in an atrophic mandible. During secondstage surgery, a split-thickness labial flap is reflected and apically repositioned by being sutured onto the periosteum and connective tissue. A palatal mucosal graft is then sutured onto the recipient site. The stent is worn for at least 4 weeks following surgery. This procedure helps to eliminate mobility of the mucosa in the area, deepen the vestibule, and prevent muscle reinsertion.