International Journal of Periodontics & Restorative Dentistry, 05/2003

Various grafting materials have been used in guided bone regeneration procedures to augment alveolar ridges deficient in horizontal or vertical dimensions or both. Autogenous block grafts from intraoral and extraoral sites have been used for ridge augmentation with encouraging results. However, the risk of vascular and neurologic injury at the donor site as well as postoperative patient morbidity have been reported following these surgical procedures. The use of a cancellous block allograft could be one alternative to avoid potential donor site complications. Five deficient alveolar ridges in three patients were each grafted with a freeze-dried cancellous block allograft and a resorbable barrier membrane. Ridge measurements taken at baseline, graft placement, and a 6-month reentry surgery demonstrated an increase in alveolar ridge width from 2 to 4 mm. These gains in ridge width compare favorably with other guided bone regeneration studies, suggesting that a freeze-dried cancellous block allograft in conjunction with a resorbable membrane may be an acceptable alternative to the autogenous block graft in the treatment of compromised alveolar ridge deficiencies.

The goal of this study was to histologically document the effect of two different implant surfaces on the percentage of bone-to-implant apposition achieved with implants placed in human sinus grafts. The influences of implant site and postgrafting delay time were also examined. Nine healthy volunteers were scheduled to undergo posterior maxillary sinus floor augmentation in preparation for delayed implant placement. In addition to the conventional dental implants selected for each case, titanium alloy experimental implants, 2.5 mm in diameter and 8 mm in length, were custom manufactured. Each microimplant was prepared longitudinally with two different surface topographies: machined on one side and MTX microtextured on the other side. A notch prepared across the superior aspect of the implants facilitated placement and provided a reference line between the two surfaces. Patients were divided into two groups that received the experimental microimplants at the time of conventional implant placement: Group A (six patients) received the experimental microimplants in the regenerated lateral wall of the sinus graft 11 months after graft placement, and group B (three patients) received them in the alveolar crest 6 months after graft placement. After 6 months of submerged healing, all experimental and conventional implants appeared to be clinically osseointegrated. Histologic analysis revealed that the mean bone-to-implant apposition was significantly greater with MTX (72.31% ± 17.76%) compared to machined surfaces (38.01% ± 19.32%), regardless of bone quality. The healing time between graft and implant placement and implant location did not statistically impact the percentage of bone-toimplant apposition.

The aim of the present study was to determine the influence of gingival dimensions on the development of gingival recession following placement of artificial crowns. The study population consisted of 11 periodontally healthy patients in whom 44 maxillary anterior teeth and/or premolars had to be crowned. A total of 36 teeth (82%) had, after crown placement, a mean intracrevicular crown margin of 0.57 ± 0.47 mm. Thirty-nine teeth without restorations served as controls. Immediately after incorporation, as well as after 3, 6, 9, and 12 months, periodontal examinations were carried out. Gingival thickness was determined sonometrically and averaged 1.25 ± 0.40 mm. Mean periodontal probing depth was 1.80 ± 0.54 mm. Twelve months later, crowned teeth had experienced a mean attachment loss of 0.17 ± 0.99 mm as compared to an attachment gain of 0.18 ± 0.46 mm at control teeth. At test teeth, the gingival margin had receded a mean of 0.43 ± 0.74 mm. In multivariate analyses considering the correlated structure of the data employing generalized estimating equation methods, crown placement was identified as a major factor for attachment loss and development of gingival recession. In addition, a shallow probing depth and narrow band of gingiva negatively influenced the level of periodontal attachment. The present results point to the importance of a more detailed periodontal diagnosis of the dentogingival region before placement of artificial crowns.

Osteoporosis is a systemic disease in which the skeletal condition is characterized by a decreased mass of normally mineralized bone. It is considered the most common metabolic bone disease, and it constitutes a major public health problem. Given the evidence that alveolar processes provide the bony framework for tooth support, the decline of skeletal mass has to be correlated with an increased risk of oral bone loss and has a negative consequence on tooth stability. Data from past research confirm that aging and estrogen depletion have a negative influence on both tooth retention and residual alveolar crest preservation. The goal of the present article is, however, to underline how the morphostructural evolution of the edentulous maxilla is mainly due to mechanical factors as the result of alterations in maxillary function. The advantages of prosthetic rehabilitation supported by osseointegrated implants are also considered, focusing the therapeutic role of this procedure on preserving the residual alveolar ridge from atrophy.

The Brånemark Novum system is a new procedure for the one-day reconstruction of periodontally hopeless or edentulous mandibles. It consists of a series of four drill templates and eight drill guides to precisely position three implants that are completely level and parallel to one another. A prefabricated lower bar is attached to the implants. A prefabricated upper bar attaches precisely to the lower bar. The restorative clinician takes a bite registration at a previously established vertical dimension of occlusion. The case is waxed up and tried in the same day and delivered after processing. The procedure is described in detail, and 11 cases are reviewed.

Closely matching natural teeth with an artificial restoration can be one of the most challenging procedures in restorative dentistry. Natural teeth vary greatly in color and shape. They reveal ample information about patients' background and personality. Dentistry provides the opportunity to restore unique patient characteristics or replace them with alternatives. Whether one tooth or many are restored, the ability to assess and properly communicate information to the laboratory can be greatly improved by learning the language of color and light characteristics. It is only possible to duplicate in ceramic what has been distinguished, understood, and communicated in the shade-matching process of the natural dentition. This article will give the reader a better understanding of what happens when incident light hits the surface of a tooth and give strategies for best assessing and communicating this to the dental laboratory.

The aim of the present study was to compare the efficacy of guided tissue regeneration (GTR) using two different biodegradable barriers (polylactide acetyltributyl citrate; polydioxanon) in three- and two-walled infrabony defects. The polydioxanon barrier is an experimental GTR membrane that consists of a continuous occlusive barrier with a layer of slings on the side that is meant to face the mucoperiosteal flap. Fifteen patients provided 15 pairs of similar contralateral periodontal defects: 12 predominantly two-walled and 18 predominantly three-walled infrabony defects. Each defect was randomly assigned to treatment with polylactide acetyltributyl citrate (control) or polydioxanon (test) devices. At baseline, 6, 12, 18, and 24 months after surgery, clinical measurements were performed and standardized radiographs obtained (not at 18 months). Both treatments revealed a significant Gingival Index reduction, probing depth reduction, and vertical probing attachment level gain 24 months after surgery. Both treatments showed slight resorption of the crestal alveolar ridge after 24 months, which failed to reach statistical significance. A statistically significant bone gain within the infrabony pockets was measured for both treatment options 24 months postsurgical. Regarding Gingival Index and probing depth reduction as well as vertical probing attachment level and bone gain, there were neither statistically significant nor clinically relevant differences between test and control barriers. The use of both biodegradable barriers in GTR therapy may be recommended.

The loss and replacement of anterior maxillary teeth pose several challenges. Treatment must successfully address immediate tooth replacement, esthetics, patient comfort, and psychologic acceptance. The purpose of this case report is to present a prosthetic and surgical technique for immediate tooth replacement following extraction in an area of severe localized bone loss. Combined full- and partial- thickness flaps associated with the use of Bio-Oss collagen grafting material and a Bio-Gide membrane were used for alveolar ridge reconstruction. To improve the final esthetic result, a connective tissue graft was used to increase ridge volume and papillary height.

Some of the most difficult problems to resolve in daily clinical practice are those where there is interaction of various pathogenic factors, with consequent complication of the therapeutic solutions. Combined treatments based on sound diagnosis of the case and appropriate decision making to organize the therapeutic procedures in sequence are the best way of dealing with such situations. This article describes the case of a woman who was pregnant at the beginning of the treatment and had active periodontitis and angle Class II molar malocclusion because of loss of maxillary and mandibular teeth. She had had maxillofacial surgery years before with average results, had lost teeth because of caries, and was seeking a solution to her problems that would be both esthetically pleasing and functional. A system that combined odontologic decision making with phased periodontal, orthodontic, and prosthodontic treatment was adopted, leading to a stable, esthetic, and functional solution that fulfilled the patient's requirements.

The aim of the present study was to evaluate the clinical outcome following application of an enamel matrix derivative in degree II mandibular furcation involvements. Ten patients with chronic periodontitis, presenting a total of eight buccal and eight lingual degree II furcation involvements, were included in the study. The following clinical parameters were evaluated prior to treatment and after 6, 12, and 36 months: probing attachment level in horizontal direction in the buccal and/or lingual furcation area (PAL-H) and probing attachment level in vertical direction (PALV) at the center of the buccal/lingual furcation area. The postoperative healing phase was uneventful in all cases, and no complications were observed throughout the entire study period. At 6 months, the mean PAL-H of the buccal defects was reduced from 4.0 ± 1.3 mm to 2.6 ± 1.4 mm, and the mean PAL-V was reduced from 5.2 ± 2.0 mm to 4.0 ± 1.6 mm. At the lingual defects, the mean PAL-H was reduced from 3.6 ± 1.3 mm to 3.1 ± 1.1 mm, and the mean PAL-V was reduced from 5.6 ± 2.0 mm to 4.3 ± 1.8 mm. At 12 and 36 months, clinical parameters remained similar, without any further clinical improvement. These results suggest that the treatment of degree II mandibular furcation involvements with enamel matrix derivative might lead to clinical improvement. However, controlled clinical trials and histologic studies are needed to examine the clinical significance of these results and the characteristics of healing following application of enamel matrix derivative.