Quintessence International, 10/2007

This clinical report illustrates with clinical cases the indications and limits of microabrasion in patients with discolored anterior teeth. The proposed techniques are based on the elimination of the dysplastic external enamel layer through microabrasion, completed by home bleaching and the use of modern adhesive restorative techniques, if necessary. In specific cases, the proposed technique may eliminate dysplastic enamel lesions without being invasive. The use of minimally invasive techniques based on microabrasion allows for treatment of slight enamel defects. In more severe cases, megabrasion combined with a minimally invasive adhesive resin composite restoration may present a valuable alternative to microabrasion. Parole chiave: enamel dysplasia, home bleaching, megabrasion, microabrasion, minimally invasive treatment, white spot lesion

The intraoral occurrence of granulocytic sarcoma is extremely rare. This article describes 2 cases of granulocytic sarcoma of the gingiva in different clinical situations: one as a precursor to acute myeloid leukemia in a 50-year-old man and the other as a sign of blast crisis in a 59-year-old man with chronic myelomonocytic leukemia. Clinicians and oral surgeons should consider the possibility of tumorous lesion and systemic disease when an intractable ulcer is encountered in an oral cavity. Early diagnosis may improve prognosis and increase expectancy of survival. Parole chiave: acute myeloid leukemia, chloroma, chronic myelomonocytic leukemia, extramedullary myeloid tumor, gingiva, granulocytic sarcoma, ulcer

Unilateral transmigration of mandibular canines is a rare phenomenon. Occurrence of bilateral transmigration of mandibular canines is even more rare. There are diagnostic, therapeutic, and prognostic implications in the occurrence of these transmigratory patterns. Proper understanding of the mechanisms involved in the impaction and intra-osseous movement of these teeth within the bone will help clinicians to intervene and formulate better treatment options. A review of previously reported cases of bilaterally transmigrating mandibular canines from the literature was undertaken. Five new cases are reported in this article. Classification of the bilaterally transmigrating mandibular canines is proposed for better understanding, ease of communication, and appropriate management of this aberrant migratory pattern. Parole chiave: bilateral transmigration, classification, impacted, intraosseous, mandibular canine

Objective: To evaluate the marginal microleakage in enamel and dentin/cementum walls in preparations with a high C-factor, using 3 resin composite insertion techniques. The null hypothesis was that there is no difference among the 3 resin composite insertion techniques. Method and Materials: Standardized Class 5 cavities were prepared in the lingual and buccal aspects of 30 caries-free, extracted third molars. The prepared teeth were randomly assigned to 3 groups: (1) oblique incremental placement technique, (2) horizontal incremental placement technique, and (3) bulk insertion (single increment). The preparations were restored with a 1-bottle adhesive (Single Bond, 3M ESPE) and microhybrid resin composite (Z100, 3M ESPE). Specimens were isolated with nail varnish except for a 2-mm-wide rim around the restoration and thermocycled (1,000 thermal cycles, 5°C/55°C; 30-second dwell time). The specimens were immersed in an aqueous solution of 50 wt% silver nitrate for 24 hours, followed by 8 hours in a photo-developing solution and evaluated for microleakage using an ordinal scale of 0 to 4. The microleakage scores obtained from occlusal and gingival walls were analyzed with Wilcoxon and Kruskal-Wallis nonparametric tests. Results: The null hypothesis was accepted. The horizontal incremental placement technique, the oblique incremental technique, and bulk insertion resulted in statistically similar enamel and dentin microleakage scores. Conclusion: Neither the incremental techniques nor the bulk placement technique were capable of eliminating the marginal microleakage in preparations with a high C-factor. Parole chiave: adhesion, adhesive, C-factor, dentin, enamel, resin composite

This report describes the case of an 82-year-old woman who presented with the chief complaint of a mild pain and gingival swelling of 2-months' duration in the buccal aspect of her mandibular left premolar region. The condition was initially diagnosed as a periodontal abscess and was treated as such by the referring clinician. The initial periapical radiograph provided by the clinician demonstrated horizontal alveolar bone resorption associated with active periodontal disease, which appeared to be more severe between the 2 premolars adjacent to the swelling. After more detailed clinical evaluation of the area and examination of the adjacent teeth, including vitality testing, it was concluded that the condition was not related to dental or periodontal disease. Consequently, a biopsy specimen was taken, and the histopathologic examination of the lesion proved it to be an odontogenic keratocyst. The case is reported because of the unusual clinical and radiographic findings associated with this lesion. Early diagnosis and appropriate treatment of odontogenic keratocyst can reduce the possibility of recurrence. However, misinterpretation of such a condition as endodontic or periodontal disease may lead to incorrect treatment planning and possibly unnecessary complications. Parole chiave: differential diagnosis, odontogenic keratocyst, periodontal disease, radiology

Objective: To evaluate the response of human pulps capped with a calcium hydroxide [Ca(OH)2] cement after bleeding control with 2 hemostatic agents. Method and Materials: Pulps were exposed on the occlusal floor, and the bleeding was controlled either with saline solution (SS) or 2.5% sodium hypochlorite (NaOCl) (SH). After that, the pulp was capped with Ca(OH)2 cement and restored with resin composite. After 30 (groups SS30 and SH30) and 60 (groups SS60 and SH60) days, the teeth were extracted and processed with hematoxylin-eosin and categorized in a histologic score system. The data were subjected to Kruskal-Wallis and Mann-Whitney tests (a = .05). Results: Regarding dentin bridge formation, an inferior response of SH60 group was observed when compared to SS60 (P .05). The response of the SH30 group generally was similar to that of the groups treated with saline solution. However, after 60 days, 2.5% NaOCl showed a trend toward having an inferior response. Conclusion: Using saline solution as a hemostatic agent before pulp capping with Ca(OH)2 resulted in a significantly better histomorphologic response than using 2.5% NaOCl as a hemostatic agent before capping with Ca(OH)2. Parole chiave: biocompatibility, calcium hydroxide, hemostatic agents, human pulp, pulp therapy, saline solution, sodium hypochlorite

Ectodermal dysplasia is a rare congenital hereditary entity. The most commonly observed forms of ectodermal dysplasia are the hidrotic and hypohidrotic types; discrimination is based on the absence or presence of sweat glands. In this report, a child with hypohidrotic ectodermal dysplasia having true anodontia of the primary dentition is presented. Physical, mental, and intraoral examinations were performed. Photographs and occlusal and panoramic radiographs were taken. A medical consultation and biopsies were requested. Mentally, the patient was normal. His hair and eyebrows were light colored and sparse. He had frontal bossing, a saddle nose, reduced vertical facial dimension, and prominent supraorbital ridges and chin. Radiographs revealed absence of all primary and permanent teeth except the bilaterally unerupted maxillary permanent canines. An armpit biopsy specimen revealed the absence of eccrine and apocrine glands. A removable prosthesis was made to satisfy the patient's esthetic and functional needs. The absence of primary teeth (true anodontia) is a rare phenomenon. It is claimed that primary teeth must be present for the development of their permanent successors. In the present case, however, the permanent canines existed despite the absence of their predecessors. Dental clinicians can be the first to diagnose ectodermal dysplasia. The dental team should be aware of its signs and symptoms in order to provide the correct therapies for the functional and psychologic needs of these patients. Parole chiave: anodontia, hypohidrotic ectodermal dysplasia, primary dentition

Rehabilitation of the chewing function of a patient depends on the quality and volume of the existing jawbone. Vertical augmentation of the jawbone is often a challenge for the dental surgeon. Various transplantation methods, from transplantation of autogenous bone to use of bone substitute material, have been described and discussed and are often controversial. Vertical distraction presents an alternative to preimplantation augmentation of vertically reduced bone. The technique offers certain advantages over conventional augmentative methods. Parole chiave: alveolar process, distraction, implants, osteogenesis, vertical bone deficiency

Objective: To assess in vitro the bond strength of a machined surface of a Au-Ti alloy to a veneering ceramic. Method and Materials: Metal strips of the alloy Au 1.7-Ti 0.1-Ir were milled from a semiproduct fabricated by continuous casting and cold forming. For comparison, the same alloy as well as a traditional Au-Pt-Pd-In alloy were used in the as-cast state. Six samples of each group were fabricated for the crack initiation test, according to ISO 9693:1999, by preparing appropriate metal strips that were veneered with ceramic using a standard firing procedure. The crack initiation test was performed in a universal testing machine. Load at fracture was recorded. Means of bond strength were calculated for each group and the results compared by use of a 1-sided Student t test (P .05). Fracture sites were documented by means of SEM. Results: Bond strength in the 3 groups was in the same order of magnitude. Failure mode was different for both alloys. Failure of the bonding to the Au-Ti alloy predominantly occurred at the alloy-oxide interface, no matter which fabrication process was used. On the Au-Pt-Pd-In alloy, more ceramic residues were observed. Conclusion: The machined alloy Au 1.7-Ti 0.1-Ir provides sufficient bond strength to veneering ceramics, but this has to be proven by a clinical study. Parole chiave: CAD/CAM systems, crack initiation test, dental alloys, gold-titanium alloy, porcelain-fused-to-metal technique, 3-point flexure bond test

Ameloblastic carcinoma is a rare malignant lesion with characteristic histologic features and behavior that dictate a more radical surgical approach than does a simple ameloblastoma. Clinically, ameloblastic carcinoma is more aggressive than most typical ameloblastomas with extensive local destruction, perforation of the cortical plate, extension into surrounding soft tissues, numerous recurrent lesions, and metastasis, usually to cervical lymph nodes. The radiographic appearance of ameloblastic carcinoma is consistent with that of ameloblastoma except for occasional presence of some focal radiopacities, apparently reflecting dystrophic calcification. Histologically, the tumor cells resemble cells seen in ameloblastoma but show cytologic atypia, cellular pleomorphism, nuclear hyperchromatism, mitoses, and vascular and neural invasion. These identifying features of ameloblastic carcinoma must be known and recognized by dental practitioners. It is probable that ameloblastoma, like other tumors (such as carcinoid tumors and epithelial tumors of the ovary), shows a spectrum of histologic and biologic behavior ranging from benignity at one end to frank malignancy at the other. A case of ameloblastic carcinoma of the maxilla in a 70-year-old man is reported. Parole chiave: ameloblastic carcinoma, ameloblastomas, tumors

Objectives: To clinically evaluate the jet injection Injex (Rösch AG Medizintechnik) using 2 different anesthetic solutions, and to compare the jet injection and the standard needle injection techniques. Method and Materials: Of the 32 patients in the study, 10 received mepivacaine 3% anesthetic solution by means of the jet injection technique, while the remaining 22 patients received lidocaine 2% with epinephrine 1:80,000 by the same method. The 14 patients in whom pulp anesthesia was achieved were selected for an additional evaluation of the pulp reaction using standard needle injection anesthesia. The differences between the 2 compounds with Injex were statistically evaluated by means of independent-samples t test analysis. The differences between subgroups receiving both jet injection and needle injection anesthesia were evaluated by means of paired t test analysis. Results: The administration of mepivacaine 3% using Injex did not achieve pulp anesthesia in any of the 10 patients, although the soft tissue anesthesia was successful. The administration of lidocaine with epinephrine using Injex resulted in pulp anesthesia in only 14 patients; soft tissue anesthesia was observed in all patients of this group. There was no statistically significant difference between Injex and the needle injection technique in onset of anesthesia. However, the duration of anesthesia was significantly longer for the needle infiltration group than for the Injex injection group. Conclusion: The anesthetic solution should be combined with a vasoconstriction agent when the Injex technique is implemented. Parole chiave: epinephrine, jet injection, lidocaine, local anesthesia, mepivacaine, needle-less anesthesia

Streptococcal infections of oral tissues are mainly seen in young children who experience a variety of upper respiratory tract infections. The disease is characterized by fever, lymphadenopathy, and ulcers on the gingiva, lips, and tonsils. This case report presents an atypical streptococcal infection of the gingiva in an 18-year-old man. The patient was referred to the periodontology department complaining of a 2-month history of gingival enlargement. He had persistent fever (39.5°C) and general malaise for 2 weeks. Intraoral examination revealed extremely inflamed and enlarged gingiva with spontaneous bleeding and suppuration. Based on the otolaryngologic consultation and the hematologic, immunologic, and microbiologic tests, the final diagnosis was an atypical streptococcal gingivitis with chronic adenoid-related mouth breathing and oral hygiene neglect as contributing factors. Treatment consisted of a broad-spectrum antibiotic regimen, supragingival and subgingival debridement, adenoidectomy, and scaling and root planing. A good response to nonsurgical therapy was achieved despite poor patient compliance, and no recurrence of gingival enlargement was observed after 1 year. Streptococcal gingivitis should be included in the differential diagnosis of suppurative gingival enlargements. Furthermore, chronic mouth breathing may initiate and/or contribute to this disease. Parole chiave: adenoid, gingival inflammation, leukocytosis, mouth breathing, streptococcal gingivitis, suppuration

Objective: To evaluate the influence of firing procedures on the marginal distortion of electroformed metal-ceramic crown restorations. Method and Materials: Twenty-four standardized specimens were fabricated using a gold-electroforming system and were characterized by 3 finish line forms: shoulder (S-type), rounded shoulder (RS-type), and deep chamfer (DC-type) preparations. Marginal discrepancies were measured at 6 stages: before the firing procedures, after the gold-bonder application, after the opaque porcelain firing, after the dentin porcelain firing, after the enamel porcelain firing, and after the glazing firing. Marginal discrepancy values were recorded at 60 randomly chosen points along the circumferential margin using a laser microscope. Marginal distortion values were defined as the differences in the marginal discrepancies between the baseline (prefiring) levels and those after each firing procedure. All statistical analyses were performed using the Friedman and Kruskal-Wallis tests (a = .05). Results: For all of the finish line forms, the marginal distortion values were altered by the subsequent firing procedures. The largest marginal distortion values were observed after the first firing procedure. The total marginal distortion values were 34.2, 6.9, and 5.2 µm for the S-, RS-, and DC-type preparations, respectively. Conclusion: The porcelain-firing procedures influenced the marginal distortion of electroformed metal-ceramic crown restorations. The marginal distortion values of the S-type preparations were the highest among the 3 groups tested. Parole chiave: crown, dental porcelain, electroforming, firing procedure, marginal adaptation, metal-ceramic restoration

Objective: Anxiety before receiving dental treatment is widespread. The aim of this investigation was to evaluate the effect of a brief psychologic treatment on adherence to the dental treatment regimen in patients with dental phobia. Method and Materials: Dental phobic patients (n = 160) received 3 sessions of cognitive behavioral therapy that consisted of stress management training and exposure to phobic stimuli. The outcome was determined in terms of 3 subsequent dental visits. Results: Participating patients had not visited a dental clinician for an average of 6 years. Comparison of patients who completed the psychologic treatment with those who dropped out showed that 68% of the former but also 52% of the latter adhered to the subsequent dental treatment regimen. The number of psychologic treatment sessions correlated significantly and positively with anxiety level before treatment. Conclusion: Short-term psychologic therapy of 3 sessions results in a success rate of 70% to adherence to dental treatment among dental phobic patients. Duration of avoidance of anxiety before treatment was not related to success in completing the trial. Nevertheless, the more intense the patient's phobia, the more psychotherapeutic sessions were necessary. Parole chiave: avoidance, cognitive behavioral therapy, dental anxiety, dental phobia, exposure, stress management training