Quintessence International, 04/2008

Extracted teeth can be bonded directly to adjacent teeth as a noninvasive long-term provisional tooth replacement. In this case report, step-by-step clinical procedures are described for using an incisal splint to simplify and ensure a precise repositioning of the extracted tooth after removal of its root. The essential steps include (1) fabrication of an incisal splint, (2) tooth extraction, (3) root removal and pontic contouring, and (4) direct bonding of the natural pontic. Using this technique, a long-term provisional fixed tooth replacement with an acceptable functional and esthetic outcome can be obtained. Keywords: adhesive, immediate tooth replacement, incisal splint, provisional prosthesis, resin-bonded fixed partial denture, single-tooth replacement

Endosseous implants present high survival rates within a 10-year observation time; however, implant failure and biologic complications are not completely avoidable. Although specific bacteria, dental plaque, and environmental factors are associated with peri-implant disease, there are currently no reliable predictors of peri-implantitis occurrence and severity. Disagreement about which clinical measures of peri-implant health are of diagnostic value continues because of the complexity of the disease process. Thus, identification of genes that control or modify aspects of the host response may provide a method to identify individuals at an elevated risk for peri-implant infections. Elevated levels of the inflammatory cytokine interleukin-1 (IL-1) in the crevicular fluid around diseased implants seem to play an important role in the pathogenesis and severity of peri-implantitis. The purpose of this review article was to critically address the genetic associations regarding IL-1 genotype claimed for peri-implant disease and to validate the use of IL-1 genetic susceptibility tests. It was revealed that the diagnostic value of both IL-1 genotyping and genetic tests for peri-implantitis should be reconsidered before altering treatment planning, regimens, and maintenance in implant dentistry. Keywords: genotype, host response, interleukin-1, peri-implantitis, susceptibility

Objective: To quantitatively test the hypothesis that a new paint-on bleaching gel has the potential to lighten tooth color in clinical situations and to evaluate the change of the tooth color six months after the bleaching procedure. Method and Materials: Ten adult subjects requesting tooth bleaching were selected to participate in this randomized clinical trial involving a new in-office bleaching technique using VivaStyle Paint On Plus (Ivoclar Vivadent), originally designed as an over-the-counter bleaching gel. Digital images and CIE L*a*b* spectrophotometric measurements were taken at baseline (I), after the bleaching treatment (PB), and 6 months after bleaching (6M). Differences in L*a*b* values were tested with a repeated measures analysis of variance (ANOVA). Differences in DELTA E values were tested with a factorial ANOVA. Results: Significant (P .05) differences were detected in L*, as well as in a* and b* values, between initial (I) and post-bleaching (PB) and between initial (I) and 6 months post-op (6M). In contrast, there was no significant difference between post-bleaching (PB) and 6 months post-op (6M). Conclusion: This new bleaching technique proved to be efficient over a period of 6 months. It could be a less aggressive and more convenient alternative to traditional bleaching techniques. Keywords: OTC bleaching products, randomized clinical trial, vital bleaching

Proteus syndrome is an extremely rare congenital disorder with progressive asymmetric overgrowth of multiple tissues. The etiology is unknown to date. The aim of this article was to describe the clinical and radiographic periodontal findings and other oral manifestations in a patient with Proteus syndrome. A 13-year-old Caucasian Brazilian girl with Proteus syndrome was evaluated by means of clinical examination and full-mouth intraoral radiographic analysis. The patient showed skeletal malformations; gigantism; facial phenotype; and overgrowth of multiple tissues, including disproportionate overgrowth of skull, left hand, and lower limbs. Evaluation of the plantar surface of the left foot showed cerebriform connective nevus. The hands also showed reduced range of motion. Intraoral examination revealed enamel hypoplasia of permanent teeth restricted to the left side of the mouth, generalized gingival overgrowth, abundant dental plaque, and malpositioned teeth. Neither periodontal pockets nor alveolar bone destruction were detected. In conclusion, oral manifestations of Proteus syndrome may include gingival overgrowth and malposition of teeth, as well as unilateral enamel hypoplasia, as shown in this case report. Keywords: enamel hypoplasia, gigantism, gingival hyperplasia, Proteus syndrome

Objective: To determine the fracture resistance of resin-bonded fixed partial dentures (RBFPDs) by examining the influence of framework design and abutment mobility. Method and Materials: RBFPD frameworks were made of zirconia (Cercon Base, Degudent) or a nonprecious alloy (reference; Dentitan, Elephant Dental) and veneered with ceramic (Cercon Ceram S, Degudent). The zirconia framework design varied between a 2-retainer RBFPD with 3 different levels of tooth mobility (groups 1 to 3) and a 1-retainer cantilever version with 2 different grades of tooth mobility (groups 4 and 5). To achieve different mobility (rigid, medium, movable), the roots of the teeth were covered with a polyether material of different thicknesses. All RBFPDs were adhesively luted on prepared human teeth (Panavia 21 Ex, Kuraray). The specimens were mechanically (1.2 3 106; 25 N) and thermally (6,000 3 5°C/55°C; 2 minutes per cycle) cycled and finally loaded to failure (universal testing machine 1445, Zwick) at a speed of 1 mm/min. Results: The fracture force of the reference RBFPD (541 N) was significantly higher than that of both cantilever RBFPDs (group 4 = 271 N, group 5 = 104 N) and one 2-retainer group with rigid abutments (group 3 = 150 N). With 2 movable abutments, the fracture force increased to 261 N (group 1) and with mixed movable/rigid teeth to 324 N (group 2). Zirconia RBFPDs showed improved survival with increased tooth mobility, but the framework design showed only a minor influence on loss rate and fracture resistance. Conclusions: Assuming chewing forces in anterior areas between 200 and 300 N, 1- and 2-retainer zirconia RBFPDs may be suitable as minimally invasive provisional alternatives to metal-supported RBFPDs. Keywords: adhesive denture, all-ceramic, metal-free, zirconia

Objective: The aim of this multicenter study was to evaluate the clinical efficacy of a strontium chloride-containing desensitizer, Hyposen (Lege Artis), over 6 months. Method and Materials: A total of 142 patients with hypersensitivity in 9 dental practices and 2 clinical departments were included in the double-blind, randomized, placebo-controlled study. Each patient exhibited at least 2 hypersensitive and caries-free teeth with exposed dentin surfaces. One tooth was treated with strontium chloride (SR) as recommended by the manufacturer, another with a placebo. Levels of hypersensitivity were assessed after 2, 8, 12, and 24 weeks by cold air and tactile stimuli. After 6 months 132 patients could be reexamined. Results: A reduction of discomfort and pain was observed in 95 patients (72%) after treatment with SR. Statistical analysis showed a significant positive effect of SR compared to the placebo group (P .05, McNemar test). Conclusion: Use of SR for desensitizing hypersensitive dentin is an effective alternative to existing desensitizing agents. Keywords: clinical investigation, dentin, dentin hypersensitivity, desensitizing agents, strontium chloride

Simple bone cysts, also referred to as traumatic bone cysts, are benign connective tissue-lined cavities occurring most commonly in young people. Most of the time, they occur as solitary radiolucencies. In the jaws, they also have been reported to occur concurrently with benign fibro-osseous lesions. The radiographic appearance of simple bone cysts could be confused with other jaw cysts and benign tumors. This case report presents a patient who had 3 separate lesions simultaneously within the mandible. The right mandibular lesion presented as a multilocular radiolucency. The 2 left mandibular lesions were periapical, with mixed radiodensities and radiographically mimicked lesions of focal or periapical cemento-osseous dysplasia. More aggressive benign lesions of the jaw were initially included in the differential diagnosis, as well. A biopsy revealed the diagnosis of simple bone cysts in all 3 locations. Minimal surgical management resulted in complete recovery of these osseous defects only to recur in 2 years on the mandibular left premolar-molar region. A new biopsy confirmed that the lesion was a recurrent simple bone cyst. Simultaneous presence of benign cemento-osseous dysplasia was also considered, as it is known to coexist with the simple bone cysts. Keywords: cemento-osseous dysplasia, recurrent bone cysts, simple bone cysts, traumatic bone cysts

Objectives: The problem of occlusion pattern for prosthetic or orthodontic rehabilitation continues to be discussed in the literature. This controversial dilemma may be solved by studying the prevalence of dynamic occlusions in natural permanent dentition. The aim of this study was to assess which schemas of dynamic occlusion are typical of natural dentition in young and older subjects and to determine if any dynamic occlusions are dependent on gender or age. Method and Materials: A total of 834 subjects with natural dentition and no prosthetic replacements were included in the study. The age of the subjects ranged from 20 to 63 years. Dynamic occlusions in all subjects were identified during clinical examination of lateral and protrusive tooth-guided excursions of the mandible. Results: The following dynamic occlusions were found: bilateral and unilateral canine-protected occlusion, group function occlusion, balanced occlusion, and "other occlusions." Occurrences of particular forms of dynamic occlusion were almost the same in men and women; however, some of the occlusions were dependent on age. The frequencies of bilateral and unilateral canine-protected occlusions decreased with age, while the frequency of group function occlusion increased. The frequencies of balanced occlusion and "other occlusions" were very low and remained nearly unchanged in relation to age. Conclusion: Bilateral canine-protected and group function occlusions were the most typical occlusions for younger patients, while group function occlusion was more common for older patients. The canine-protected occlusion seems to be the most suitable pattern for orthodontic and prosthetic rehabilitation planned in younger patients, while the group function occlusion may be a good pattern for prosthetic rehabilitation in older patients. Further studies are needed to determine the relationship of the occlusal schemas to periodontitis, bruxism, or temporomandibular disorders. Keywords: balanced occlusion, canine-protected occlusion, group function occlusion, orthodontics, prevalence, prosthetics

Hepatitis C virus (HCV) infection is a liver disease characterized by the development of necrosis, inflammatory changes, and progressive liver fibrosis, leading to complications including cirrhosis, end-stage liver disease, and hepatocellular carcinoma. The clinical features resemble those of other forms of acute viral hepatitis, namely, malaise, nausea, abdominal discomfort, pale stools, dark urine, and jaundice. The most frequently reported extrahepatic manifestations of HCV are lichen planus, sialadenitis, and cutaneous lesions. Sjögren's syndrome-like symptoms and lichenoid reactions have been previously reported in association with hepatitis C. This article describes a case of sicca-like syndrome and oral lichenoid reaction associated with interferon-alpha therapy for HCV infection. In this unique case, significant oral symptoms arose right after initiation of interferon-alpha treatment and resolved completely within days upon completion of treatment with interferon-alpha. Physicians and oral health care specialists should be aware of the association among HCV infection, interferon-alpha therapy, and development of possible oral signs and symptoms including lichenoid lesions and xerostomia. Keywords: dry mouth, hepatitis C, interferon alpha, lichenoid reactions

Objective: To evaluate the clinical effectiveness of the Vector system (Dürr Dental) in excess cement removal from subgingival margins during fixed prosthodontic treatment. Method and Materials: A total of 41 subjects, each in need of a minimum of 2 metal-ceramic crowns in different quadrants, took part in this study. Altogether, 156 abutment teeth were randomly assigned into 2 groups: In one group, excess cement was removed with the Vector system after cementation of provisional and permanent restorations, while in the other group, handheld instruments were used for this procedure. The clinical parameters Plaque Index (PI), Gingival Index (GI), and probing pocket depth (PPD) were recorded at baseline, at the same appointment after cementation of provisional restorations, 2 weeks later after cementation of permanent restorations, and 3 weeks after final cementation. Results: Both the Vector system and the handheld instruments were able to reduce PPD and PI significantly at 2 and 5 weeks, but no significant differences could be demonstrated between the groups. Regarding GI, significant reductions were found at 2 and 5 weeks for the Vector group (P .001), whereas for the handheld instrument group, the only significant difference could be demonstrated at 5 weeks (P = .001). Significant differences between the groups occurred at 2 weeks (P = .003) and 5 weeks (P = .002), with the Vector group having the greatest reduction in GI. Conclusion: Although similar reductions in Plaque Index and probing pocket depths were observed with both the Vector system and handheld instruments, the Vector system produced a significantly greater benefit in reducing Gingival Index. Keywords: excess cement removal, gingival health, Vector system

Objective: In the past, clinicians have sometimes been unwilling to provide care to patients known to be infected with hepatitis B virus (HBV). However, this lack of patient care should have lessened following the introduction of effective HBV vaccination for health care workers. The purpose of this study was to determine the willingness of clinicians in Jordan to provide care to HBV-infected patients. Method and Materials: A total of 290 general dental practices were randomly selected and surveyed for their willingness to provide treatment for toothache and routine dental care of individuals infected with HBV. Results: Only 45% of the dental practices were willing to provide care to a person infected with HBV. The unwillingness to provide treatment did not seem to be influenced by financial factors. Conclusion: HBV-infected individuals will have difficulty obtaining dental health care in Jordan. There is a need for dental heath care workers in Jordan to be better informed and/or provide more effective treatment of HBV-infected individuals. Keywords: dentist, hepatitis B, Jordan, willingness

Objective: To evaluate the usefulness of exfoliative cytology as a diagnostic tool for patients with clinical symptoms of desquamative gingivitis. Method and Materials: Fifteen patients clinically diagnosed with desquamative gingivitis were evaluated. At their first visit, a cytologic smear was performed on the gingival lesion. On their second visit, a gingival biopsy was obtained from the perilesional site. Control smears were taken from 15 patients who had no oral lesions. Results: The cytologic findings showed diffuse or collective Tzanck cells in 3 of the 15 cases. The findings of the other 12 cases were nonspecific inflammatory changes compared to the control. The definitive diagnosis for each case was made according to histopathologic and direct immunofluorescence (DIF) findings. The 3 cases in which Tzanck cells were recognized in the cytologic smear were subsequently diagnosed as pemphigus vulgaris. The cases in which only nonspecific cytologic findings were obtained were later diagnosed by biopsy and DIF as mucous membrane pemphigoid or lichen planus. Conclusion: All the cytologic findings of the 15 patients, except for 3 cases in which Tzanck cells were found, were nondiagnostic. Therefore, the use of exfoliative cytology does not appear to be appropriate as a diagnostic tool for patients showing the clinical symptoms of desquamative gingivitis, because this technique adds to the cost and delays the definitive diagnosis. However, using the cytologic technique may occasionally be of some value as a minimally invasive screening tool when pemphigus vulgaris is suspected. Keywords: desquamative gingivitis, diagnosis, exfoliative cytology, lichen planus, mucous membrane pemphigoid, pemphigus vulgaris

Gingival involvement in erosive lichen planus (ELP) is classified as nonplaque-induced gingival lesions. Occlusive steroid therapy (OST) using a plastic stent is administered to enhance the effect of corticosteroids by maximizing the contact between the corticosteroids applied on the gingiva and the gingival lesions. Clinical efficacy may be enhanced with OST even when low-potency topical corticosteroids are used. The treatment of 2 cases of gingival ELP with symptoms of intraoral pain and a long-term burning sensation is presented. In both cases, severe erythema was found in the attached gingiva. Plastic stents were constructed to provide OST. The patient was instructed to apply topical corticosteroid (0.1% triamcinolone acetonide) to the inner surface of the stent and wear the stent continuously between meals and at night. The condition of the gingiva dramatically improved by providing OST for 10 weeks (case 1) and 3 weeks (case 2). The improvement in the gingival condition has been controlled for a long period (7 to 10 months) even after OST was completed. The treatment methods shown in this report are encouraging and worthy of further study. Keywords: corticosteroids, gingiva, lichen planus, treatment

Objectives: Potential sources of exposure of the dental health team and their patients to mercury vapor in the dental clinic include accidental spillage of elemental mercury, use of mechanical amalgamators, and dry cutting of old amalgam restorations using high-speed instrumentation. The purpose of this study was to evaluate the extent of mercury exposure in Turkish dental staff by cold-vapor atomic absorption spectrometry. Method and Materials: A total of 211 clinicians, dental students, and dental nurses answered a questionnaire concerning sex, age, occupation, number of amalgam restorations performed per week, number of amalgam restorations removed per week, methods of trituration, number of amalgam restorations present in their own mouths, frequency of fish consumption, smoking, vitamin intake, and bruxism. For each subject, a 5-mL sample of whole blood was drawn and frozen until the time of analysis. Blood mercury levels were measured by means of cold-vapor atomic absorption spectrometry. Blood mercury levels were also analyzed in a control group of 58 non-dental-staff blood donors. Results: Normal blood mercury values are considered to be in the range of 0 to 5 ng Hg/mL. Of the dental staff evaluated, 51.7% had a blood concentration of mercury less than 5 ng Hg/mL, and 33.6% had a blood concentration above 5 ng Hg/mL. The difference between the test and control groups was statistically significant (P .01). Conclusion: Mercury is being absorbed as a result of dental practice but that although there is, in general, a low level of mercury contamination in the dental operatory because of amalgam work, sufficient care is being taken to prevent higher levels of contamination with an increased use of mercury. Keywords: amalgam, blood concentration, mercury, toxication