International Journal of Periodontics & Restorative Dentistry, 02/2012

Restorative treatment of the severely worn dentition is typically indicated to replace deficient tooth structure, limit the advancement of tooth destruction, improve oral function, and enhance the appearance of the teeth. Minimizing removal of additional tooth structure while also fulfilling the desire of patients to have highly esthetic restorations can present a prosthetic challenge when the existing tooth structure is already diminished. This article presents a comprehensive minimally invasive prosthetic treatment approach using a lithium disilicate all-ceramic material for the esthetic rehabilitation of a severely worn dentition for a female patient diagnosed with Sjögren syndrome.

Because of the peri-implant bone resorption that occurs when a non-platform switched implant is exposed to the oral environment, it has been recommended to maintain 1.5 mm between the tooth and implant to preserve the bone adjacent to the teeth. Several studies have documented that platform-switched implants have less peri-implant bone resorption than matched implants. This retrospective radiographic analysis studied 70 platform-switched implants placed less than 1.5 mm from an adjacent tooth and with prostheses loaded for a minimum of 6 months. The mean distance between the implant and tooth was 0.99 mm (range, 0.20 to 1.49 mm); the mean horizontal and vertical bone resorption was 0.36 and 0.43 mm, respectively. The mean bone peak reduction was 0.37 mm. The results confirm that the use of platform-switched implants reduces bone resorption after two-piece implants have been uncovered and that it is possible to place this type of implant 1 mm from teeth while maintaining the bone level adjacent to them (the bone peak).

Periodontal regeneration in patients with advanced periodontitis and severe attachment loss has classically presented some of the greatest challenges to the practitioner. The purpose of this article is to describe the staged treatment approach and long-term follow-up of a case with generalized advanced chronic periodontitis. Microbial sampling for suspected periodontopathogens was done before and after treatment. Autogenous bone grafting was used to repair bilateral mandibular vertical defects on both molars and premolars. Reentry surgery at 6 months demonstrated 100% defect fill. Clinical, radiographic, and microbiologic evidence at 8 years suggested a stable outcome. Qualitative polymerase chain reaction (PCR) analysis was done to detect the presence of cytomegalovirus, Epstein-Barr virus type 1, and common periodontopathogens 8 years after active periodontal therapy. Negative PCR results 8 years after treatment confirmed that pathogenic subgingival reservoirs were successfully eradicated.

The connective tissue graft (CTG) in conjunction with a coronally advanced flap is still regarded as the gold standard treatment for gingival recession defects. Increased surgical morbidity as well as limited tissue availability continues to spur interest in alternatives to the CTG. The current case report examines a porcinederived, double-layer collagen matrix as an alternative to the CTG in managing Miller Class I and II recession defects. A long junctional epithelial attachment as well as connective tissue adhesion were noted when collagen matrix was used in conjunction with a coronally advanced flap in recession treatment protocols. The results suggest that it is possible to obtain root coverage without harvesting connective tissue.

This retrospective radiographic study analyzed the dimensions of the alveolar bone in the posterior dentate mandible based on cone beam computed tomography (CBCT) images. A total of 56 CBCT images met the inclusion criteria, resulting in a sample size of 122 cross sections showing posterior mandibular teeth (premolars and molars). The thickness of the buccal and lingual bone walls was measured at two locations: 4 mm apical to the cementoenamel junction (measurement point 1, MP1) and at the middle of the root (measurement point 2, MP2). Further, alveolar bone width was assessed at the level of the most coronal buccal bone detectable (alveolar bone width 1, BW1) and at the superior border of the mandibular canal (alveolar bone width 2, BW2). The vertical distance between the two as well as the presence of a lingual undercut were also analyzed. There was a steady increase in buccal bone wall thickness from the first premolar to the second molar at both MP1 and MP2. BW1 at the level of the premolars was significantly thinner than that for molars. Alveolar bone height was constant for all teeth examined. For the selection of an appropriate postextraction treatment approach, analysis of the alveolar bone dimensions at the tooth to be extracted by means of CBCT can offer valuable information concerning bone volume and morphology at the future implant site.

This article describes a soft tissue surgical modification-the trap door technique-used to enhance contemporary patient esthetic expectations and preserve periodontal health longitudinally. This surgical modification is greatly indicated for single-stage single and multiple implant surgery to preserve the integrity of the papillae and eliminate buccal soft tissue concavity. This procedure also addresses the issue of interproximal papillary development to obviate the presence of a black triangle. The technique is very effective in cases of minimal interproximal bone loss, it does not require autogenous bone harvesting, and is therefore less invasive and well accepted by the patient.

The aim of this study was to test whether recombinant human platelet-derived growth factor BB (rhPDGF-BB) enhances bone regeneration in combination with ß-tricalcium phosphate (ß-TCP) granules or deproteinized bovine bone mineral (DBBM) compared to empty defects and ß-TCP granules alone. Four titanium cylinders were placed on the external cortical plates of seven rabbits' calvaria and randomly allocated to one of four groups: (1) empty, (2) ß-TCP, (3) ß-TCP + rhPDGF-BB, and (4) DBBM + rhPDGF-BB. The mean area of bone regeneration was 13.9% ± 8.4% (empty), 24.0% ± 14.8% (ß-TCP), 37.1% ± 8.9% (ß-TCP + rhPDGF-BB), and 64.4% ± 5.4% (DBBM + rhPDGF-BB), with the greatest bone regeneration noted for DBBM + rhPDGF-BB (P .01). The fraction of bone substitute material varied between 48.3% ± 9.3% (DBBM + rhPDGF-BB), 53.1% ± 10.6% (ß-TCP + rhPDGF-BB), and 58.0% ± 14.8% (ß-TCP). rhPDGF-BB combined with DBBM showed the greatest potential to enhance bone regeneration.

The use of a hydropneumatic balloon for the elevation of the sinus membrane is a new technique for sinus floor augmentation procedures. Few cases using such a technique are reported in the English medical literature. This report describes 40 patients who were treated with this technique and studied retrospectively. Forty consecutive patients with an alveolar crest-sinus floor distance (bone height) = 12 mm were enrolled. Under microscopy (40×) and using piezosurgical instruments, hydropneumatic sinus membrane elevation was performed, and a calcium sulphate solution was injected under the elevated antral membrane using a syringe. In the same surgical session, 4.00- to 6.50-mm-diameter implants were placed. Bone height at 12 months, complications related to the surgical technique, and implant failure were all recorded. Bone height at 12 months was 14.66 ± 1.48 mm, with a sinus membrane elevation of 9.01 ± 3.01 mm. Fifty-six implants were placed, and no failures were observed after 1 year. One macrolaceration and two microlacerations were the only complications related to the technique. Minimal invasiveness and reduced trauma characterize this new approach. In fact, gradual balloon inflation provides a controlled and atraumatic preparation of the sinus floor membrane. Piezoelectric instruments and microscopy make this technique predictable and safe. The relatively short learning curve of this approach for sinus floor elevation allows for its use in private practice.

The purpose of this case series was to evaluate secondary soft tissue level changes of a single-stage surgical protocol combining immediate implant placement and connective tissue grafting in maxillary incisors associated with gingival recession defects. Ten patients underwent the proposed combined treatment consisting of 11 single-tooth implant restorations. Peri-implant soft tissue level and the width of keratinized gingiva were evaluated at baseline, the time of implant restoration connection, and 2 years postrestoration. All parameters used to assess esthetic outcomes showed improvements. The proposed clinical procedure can be considered an alternative approach to achieving an ideal esthetic anterior restoration.

The physiologic tooth position is determined by interactions between the periodontal tissue and occlusal, tongue, and lip forces. Bone destruction resulting from chronic periodontal disease disturbs the equilibrium of these interactive balances, leading to pathologic tooth migration, often requiring multidisciplinary treatment approaches. The present case demonstrates a systematic periodontalorthodontic- prosthetic treatment for achieving the optimal structural, functional, and esthetic outcomes.

This 6-month randomized controlled clinical study primarily aimed to compare the results achieved by the use of a platelet-rich fibrin (PRF) membrane or connective tissue graft (CTG) in the treatment of gingival recession and to evaluate the clinical impact of PRF on early wound healing and subjective patient discomfort. Use of a PRF membrane in gingival recession treatment provided acceptable clinical results, followed by enhanced wound healing and decreased subjective patient discomfort compared to CTG-treated gingival recessions. No difference could be found between PRF and CTG procedures in gingival recession therapy, except for a greater gain in keratinized tissue width obtained in the CTG group and enhanced wound healing associated with the PRF group.

While immediate loading in the edentulous mandible is a well-documented procedure, there are limited scientific data on immediate loading in the partially edentulous mandible. Two-year success rates of immediate loading and conventional delayed loading of dental implants in partially dentate mandibles were compared. Patients were randomized into three groups: group A (n = 40), immediate provisionalization with nonocclusal loading; group B (n = 40), immediate provisionalization with occlusal loading; and group C (n = 37), delayed loading with single-stage surgery. Baseline and 2-year measurements included implant stability quotient, insertion torque, and peri-implant bone crest radiography. Two hundred nine implants were immediately loaded in 80 patients. The 2-year success rates were 93.3% for group B and 100% for groups A and C. Immediate provisionalization provided success rates similar to those for delayed loading only when not loaded in occlusion.

Excessive cantilever lengths of fixed implant-supported prostheses may have functional and biomechanical disadvantages. This study reports the clinical outcomes of unconventional implants placed for distal support of a fixed implant-supported prostheses. Seven extraoral implants with intraosseous lengths of 2.5 to 4.0 mm were placed in four patients. Distal cantilevers had a mean length of 29.8 mm (range, 18.6 to 39.3 mm). No bone loss or other adverse events were found. The prosthetic plan was maintained in all patients. Within the limits of the employed research design, this concept seems to be a successful option for fixed complete implant-supported prosthesis treatment.

This study evaluated factors that may influence the presence or absence of interproximal papillae. Clinical evaluation consisted of visual determination, and quantitative analyses were made using millimeter grids on radiographs. Patients (n = 45) were divided into three groups according to age. Data were analyzed using the chi-square test followed by the Student t test (α = .05). The distance from the contact point to the bone crest had significant influence on papilla presence in both anterior and posterior sites (P .05), whereas the width between roots of adjacent teeth did not. The papilla was missing more frequently in anterior sites. The presence of papillae was not age-dependent.

Ten similarly sized extracted maxillary central incisors were treated endodontically; carbon fiber posts were fit to five specimens and zirconia ceramic posts were fit to the other five. The same cement was used for fixation and core reconstruction. The purpose of this study was to test the strength of the two groups of specimens via a static strain test. The carbon fiber posts were seen to have greater elasticity but were subjected to such stresses so as not to recommend their use in single-rooted teeth with no clinical crowns. Their use may be recommended in other clinical situations. Zirconia ceramic posts were more reliable and stronger above all for single-rooted teeth with no crowns.