Quintessence International, 04/2010

Objective: This retrospective study evaluated the success rate of a fixed retrievable prosthesis based on an electroforming technique combining the advantages of screw- and cement-retained principles. Method and Materials: Forty patients (17 men and 23 women) with a mean age of 62.2 years were treated. A total of 353 implants were placed in the edentulous maxilla, mandible, or both jaws to allow prosthetic rehabilitations with 55 fixed prostheses. Clinical success of the implants was based on the criteria of Buser. Technical complications monitored throughout the wearing period are described. Retrievability of the restoration with a conventional crown remover was checked at 6, 12, and 36 months. The cumulative survival rate of the implants was measured. Results: After a mean observation period of 4.08 years (range 22 to 62 months), a cumulative survival rate of 99.15% was recorded for the 234 maxillary implants (234 Camlog RootLine, Camlog) and for the 119 mandibular implants (72 Camlog RootLine, 47 Camlog ScrewLine). Three implants failed before prosthetic loading. Monitored technical complications were seen in 10.91% of the restorations; they comprised ceramic chip-off and relining. Conclusions: This fixed implant-retained prosthesis based on electroforming indicates a comparable clinical efficacy to other techniques and allows scheduled retrieval. Keywords: dental implant, electroforming, fixed denture, retrievable, retrospective study, survival rate

Objectives: This study aimed to evaluate the long-term prognosis of immediately loaded fixed full prostheses for the treatment of edentulous patients with extreme bone atrophy in the posterior mandibular region. Material and Methods: Twenty-four edentulous patients with atrophic posterior mandibles were treated by means of a complete prosthesis sustained by both axial and tilted fixtures. The insertion of tilted implants was carefully planned by means of computed tomography scan analysis and measuring width and height of residual bone. Implant type, length, and diameter were chosen, as well as implant angulation, according to the All-on-Four protocol and avoiding the course of the mandibular nerve. The prosthesis was delivered no later than 2 days after implant surgery. Implant survival and prosthesis success were assessed clinically and radiographically up to 42 months of follow-up. Measurement of peri-implant bone loss was based on periapical radiographs after 12 months of loading. Results: All implants survived and all prostheses were successful at the time of this study reporting. The mean follow-up was 30.1 months with a range of 14 to 44 months. The average peri-implant bone loss was 0.85 mm after 12 months (0.8 mm for tilted implants and 0.9 mm for axial implants). No significant difference in marginal bone loss was observed between axial and tilted implants. Conclusions: The immediate rehabilitation of patients with extreme atrophic mandibles can be successful with careful planning and particular attention during the surgical placement of the implants, as shown by the excellent outcomes of the present study. Keywords: endosseous implants, extreme atrophy, immediate loading, mandible, tilted implants

Calcium salt deposits in the presence of normal calcium/phosphorus metabolism involving tissues that do not physiologically calcify are referred to as dystrophic calcification. The condition may be associated with a variety of systemic disorders. Additionally, injured tissue of any kind is predisposed to dystrophic calcification. The case of a 21-year-old man with two isolated dystrophic calcifications in the right masseter muscle is presented. Dystrophic calcifications should be studied carefully and differentiated from lesions resulting from other syndromes that manifest calcification of soft tissues. The lack of a classification system of soft tissue calcifications complicates the management and study of the condition. Keywords: calcification, choristoma, dystrophy, masseter muscle

Subpontic osseous hyperplasia is a relatively uncommon benign submucosal mass of normal bone found beneath a pontic. Three cases of mandibular subpontic osseous hyperplasia are described, adding to the 40 existing cases in the English-language literature. Subpontic osseous hyperplasia may represent a unique reactive osseous metaplasia in the subpontic region, with chronic stimuli and functional or occlusal stress as possible etiologies. This article aims to address the clinical significance, treatment considerations, and radiographic correlation of subpontic osseous hyperplasia. Keywords: bone, fixed prosthesis, metaplasia, subpontic osseous hyperplasia

Objectives: To investigate the short-term effects of nonsurgical therapy (scaling and root planing, SRP) on the subgingival microbiota in chronic (CP) and aggressive (AP) periodontal disease. Method and Materials: Ninety-seven CP and AP subjects underwent fullmouth SRP on 2 consecutive days. AP patients were randomly assigned to either receive systemic metronidazole plus amoxicillin (AP+AB) or were treated mechanically alone (AP). Pathogens were identified with 16S rRNA oligodeoxynucleotide probes and dot-blot hybridization before and at days 2, 3, 4, 7, 10, and 21 of healing. CP subjects were treated by scaling and root planing along with placebo tablets. Results: Initially, AP cell counts were 69.9- (Porphyromonas gingivalis), 10.2- (Aggregatibacter actinomycetemcomitans), 5.7- (Tannerella forsythia), and 3.3-fold (Prevotella intermedia) enhanced compared to CP cell counts. Following SRP, immediate elimination occurred in single individuals of all three treatment groups at day 2. After SRP plus antibiotic therapy (AP+AB), the prevalence scores dropped beyond the levels of AP and CP, beginning at day 7, and remained low until day 21 (P Keywords: aggressive periodontitis, early healing, periodontal pathogens, rRNA probes, suppression, systemic antibiotics

Objective: To examine the clinical performance of veneered ceria-stabilized tetragonal zirconia/alumina-nanocomposite (Ce-TZP/A-nanocomposite) frameworks for three-unit fixed dental prostheses (FDPs). Method and Materials: Eight patients in need of one FDP replacing one premolar or molar were included in this case series. Eight Ce-TZP/A- nanocomposite FDP frameworks were fabricated with a CAD/CAM system (Hint-Els) and veneered with a zirconia veneering ceramic (Vintage ZR, Shofu). The FDPs were cemented with resin cement (baseline) and were evaluated at baseline; 2 weeks; and 3, 6, and 12 months after cementation. For the technical evaluation, the USPHS criteria were used. The biologic outcome was judged by comparing the plaque control record (PCR), bleeding on probing (BOP), and probing pocket depth (PPD) of the abutment teeth (test) and untreated contralateral teeth (control). Radiographs were made at baseline and at 6 and 12 months of follow-up. The data were descriptively analyzed. Results: The mean observation period of the eight examined FDPs was 12.8 ± 1.1 months. The survival rate of the FDPs was 100%. Furthermore, no technical or biologic complications were found. No differences of the mean (m) PCR (test: 0.1 ± 0.1, control: 0.2 ± 0.2), mBOP (test: 0.2 ± 0.2, control: 0.1 ± 0.1), and mPPD (test: 2.6 ± 0.8, control: 2.6 ± 0.6) were found between test and control teeth. Conclusions: Ce-TZP/A nanocomposite was found to be a reliable framework material at 1 year of function. Longer observation periods and randomized controlled clinical trials including more patients are needed to validate these findings. Keywords: CAD/CAM, ceria-stabilized, fixed dental prosthesis, framework, zirconia, zirconia/alumina nanocomposite

Hyposalivation is represented by a reduced salivary flow rate and can be caused by etiologic factors such as systemic diseases and intake of various medications or by radiotherapy following head and neck cancer. The aim of this review was to compile data about the qualitative and quantitative changes of salivary components during hyposalivation, and to summarize their consequences for oral health. A Medline/PubMed/Scopus search was conducted to identify and summarize articles published in English and German that reported on etiology of hyposalivation and changes in the salivary composition due to hyposalivation of different origins. The search revealed 94 articles, 71 of which were original articles. Apart from the reduction of the salivary flow rate, the quality of saliva is strongly altered because of systemic diseases, medications, and radiotherapy, including increased viscosity and pH shift to more acidic values and changes in salivary protein compositions. Furthermore, hyposalivation may be accompanied by pronounced shifts in specific microbial components, in particular toward a highly acidogenic microflora. Moreover, therapy of hyposalivation is often restricted to palliative treatment (ie, saliva substitutes or gels). To prevent tooth tissue demineralization, clinicians should consider saliva substitutes that are supersaturated with calcium and phosphates and contain fluoride. Keywords: caries, drugs, hyposalivation, microflora, periodontitis, radiotherapy, saliva substitutes, Sjögren syndrome, xerostomia

Objective: To test the bacterial sealing ability of commonly used provisional endodontic restorative materials. Method and Materials: This study investigated Cavit (3M ESPE), Ketac (3M ESPE), DuoTemp (Coltène/Whaledent), and a combination technique using Ketac and Cavit. One hundred molars were randomly selected and then mounted in an apparatus that isolated the crown portion of the tooth. Provisional restorative materials were placed in an open access following manufacturer guidelines. Streptococcus mutans was applied to the samples, and results were tabulated over the course of 4 weeks. Results: Cavit and DuoTemp performed the best, and Ketac performed the worst. After 14 days, however, all materials leaked in over half of the samples. Conclusion: No material can be recommended as superior in providing a reliable seal after 14 days. Keywords: bacteria, leakage, provisional, provisional restorations

Objective: To compare the adhesion and maturation of blood components on chemically conditioned root surfaces. Method and Materials: Clinical root samples of human teeth were obtained (n = 150) and manually scaled. Five groups of 30 samples were treated as follows: (1) saline solution irrigation (control); (2) 24% EDTA gel; (3) 25% citric acid solution; (4) tetracycline solution (50 mg/mL); and (5) 30% sodium citrate solution. After these treatments, 15 samples of each group received a blood drop and were analyzed by SEM. The remaining 15 had their surface morphology evaluated for collagen fibrils exposure by SEM. Photomicrographs were analyzed according to the score of adhesion of blood components. Kruskal-Wallis and Dunn multiple comparison tests were employed. Results: The control group was characterized by the absence of blood elements on the surface. The best result was observed in the citric acid group, which had a dense fibrin network with blood elements adhered. The EDTA group showed a moderate fibrin network formation. In contrast, a scarce fibrin network and a few cells were present in the tetracycline samples, and an absence of blood elements was found on sodium citrate specimens. The citric acid group was statistically different from the control group (P < .01). No differences were found among the control, EDTA, tetracycline, and sodium citrate groups (P > .05). Conclusion: Under these experimental conditions, citric acid is indicated to stabilize clots on the root surface, which act as a scaffold for connective tissue cell development. Keywords: clot, fibrin, periodontal diseases, periodontal therapy, scanning electron microscopy, smear layer, tooth root

Objective: To investigate reactions of pulp tissue when in contact with the dentin adhesives Resulcin AquaPrime + MonoBond (RAPMB, Merz Dental), Scotchbond 1 (SB1, 3M ESPE), and Gluma Comfort Bond (GCB, Heraeus Kulzer) in comparison with calcium hydroxide after 1 to 70 days. Method and Materials: An occlusal cavity was prepared in 152 molars of 76 Wistar rats. The pulps were exposed and dentin adhesives placed on the pulp tissue of 10 molars for each dentin adhesive group and time period. Eight molars per time period served as controls and were capped with calcium hydroxide. All cavities were restored with composite resin. The animals were sacrificed 1, 3, 7, and 70 days after pulp capping. Pulp tissue was histologically evaluated for the following criteria: bacterial infection, inflammatory cells, necrosis, and reparative dentin. The data were statistically evaluated using the Kruskal-Wallis test (P < .05). Results: Overall, significantly more bacterial infections were detected 1, 3, 7, and 70 days after pulp capping with dentin adhesive (P < .05). In all dentin adhesive groups, 1 day after direct pulp capping, significantly more inflammatory cells were found, whereas after 7 days, this was only the case for the SB1 group (P < .05). After 70 days, capping with calcium hydroxide resulted in significantly less necrosis than with RAPMB and SB1 (P < .05). Regarding necrosis, SB1 showed the worst results: Pulp necrosis occurred significantly more often than with calcium hydroxide and GCB (P < .05). After the application of calcium hydroxide, significantly more reparative dentin formation occurred (P < .05). Conclusion: Direct pulp capping with calcium hydroxide seems to produce remarkably better results than with dentin adhesive. Keywords: calcium hydroxide, dentin adhesive, direct pulp capping, histology, rat, tissue reactions

Cavernous sinus thrombosis is a severe encephalic complication of the cervicofacial infections that can lead to death if not treated in adequate time. Among the several etiologies related to the development of this infection, myiasis has not been reported, enforcing the importance of the report of a case of thrombosis of the cavernous sinus developed from a facial myiasis. Keywords: infection, myiasis, ophthalmoplegia, oral diagnosis, sinus thrombosis, thrombosis

Orofaciodigital (OFD) syndrome is a generic name for a variety of different but possibly related genetic disorders that result in malformations of the mouth, teeth, jaw, facial bones, hands, and feet and are therefore categorized as oroacral disorders. Nine subtypes of OFD syndromes have been identified. OFD type V is known as Thurston syndrome, of which only 11 cases have been reported to date. A case is reported of a 19-year-old man with this syndrome. A brief review of previously reported cases and discussion of anomalies of the syndrome is presented. Keywords: autosomal recessive, median cleft lip, oroacral, orofaciodigital syndrome, postaxial polydactyly, Thurston syndrome