Quintessence International, 09/2016

Objectives: Due to the high chipping rates observed in veneered zirconia ceramic restorations, the use of monolithic zirconia restorations has been recommended. This study tried to compare veneered and monolithic zirconia fixed dental prostheses (FDPs) with respect to the amount of damage induced by endodontic access preparation. Method and Materials: Monolithic and ceramic veneered (n = 10) three-unit restorations (retainers: first premolar and first molar; pontic: second premolar) were subject to endodontic access cavity preparation in both retainers using a diamond rotary instrument under continuous water cooling. The number of chipping fractures and microfractures detected using the fluorescent penetrant method were recorded. Statistical analysis was based on Wilcoxon rank sum tests with Bonferroni correction (level of significance ? = .05). Results: Only one microfracture could be identified in the group of monolithic FDPs while a maximum of seven microfractures and three chipping fractures per retainer crown were recorded in the group of veneered restorations. At the premolar site, the veneered restorations showed significantly more microfractures (P = .0055) and chipping fractures (P = .0008). At the molar site, no significant difference with respect to microfractures could be detected (P = .0767), while significantly more chipping fractures occurred in the veneered samples (P = .0293). Conclusion: Monolithic zirconia restorations seem to be less susceptible to damage when endodontic access cavities have to be prepared as compared to veneered zirconia reconstructions. However, no conclusions can be drawn on the long-term performance of a specific restoration based on this study. Keywords: endodontic access, fluorescent penetrant method, monolithic, zirconia

Objective: Langerhans cell histiocytosis (LCH) is a rare disorder characterized by clonal proliferation of Langerhans cells that affects various organs. Oral involvement may simulate periodontal disease and cause significant diagnostic and management difficulties. Here, we present an interesting LCH case with severe periodontal destruction in a young woman in order to facilitate early recognition of this aggressive disease and successful participation of the general practitioner in the management of such patients. Case Presentation: A 21-year-old woman was referred for evaluation of recurrent episodes of dull pain in the gingiva for the last 9 months, which had not been successfully managed by her general practitioner. Clinical and radiographic examination showed extensive alveolar bone loss. Histopathologic examination revealed diffuse aggregates of Langerhans cells, while a complete work-up did not demonstrate evidence of systemic involvement. A diagnosis of LCH limited to the oral cavity was established. The patient received systemic chemotherapy in combination with appropriate dental care including gingival debridement and tooth immobilization. Following chemotherapy completion, comparative clinical, radiographic, and microscopic evaluation showed complete remission. During an 18-month follow-up period, frequent oral examinations and appropriate dental interventions confirmed the lack of LCH recurrence and guaranteed the stabilization of periodontal tissues. Conclusions: Oral soft and hard tissue involvement may be the only manifestation of LCH. The present case exemplifies the importance of close collaboration between general dentistry and its disciplines (periodontology, restorative dentistry, oral medicine, oral and maxillofacial pathology, and oral radiology), and hematology-oncology for diagnosis, management, treatment monitoring, and decision-making. Keywords: aggressive periodontitis, general practitioner, jaws, Langerhans cell histiocytosis, multidisciplinary approach, osteolytic lesions

Objective: To evaluate the clinical efficacy of a new porcine acellular dermal matrix (PADM) for the treatment of Miller Class I, II, and III multiple gingival recessions using the modified coronally advanced tunnel technique (MCAT). Method and Materials: Twelve nonsmoking, systemically healthy patients presenting at least two adjacent Miller Class I, II, or III gingival recessions (GR), with a minimal depth of 2 mm, were treated consecutively with MCAT in conjunction with PADM. At baseline and 12 months postoperatively, complete root coverage (CRC, eg 100% root coverage), mean root coverage (RC), recession depth, recession width, attached gingiva (AG), keratinized tissue (KT), periodontal pocket depths (PD), and clinical attachment level (CAL) were evaluated. The main outcome variable was CRC. Results: Postoperative healing was uneventful in all cases, without any matrix loss or exposure or infection. Statistically significant improvements (P .0001) were observed 12 months postoperatively in 53 of the included 54 GR (98.15%). Twenty two recessions (40.74%) showed CRC while the mean RC measured 73.20 ± 27.71%. Mean GR reduction was 2.06 ± 1.18 mm while the gain of AG amounted to 0.84 ± 0.73 mm and of KT to 0.69 ± 0.51 mm, respectively. There were no statistically significant changes for PD at 12 months; CAL showed a significant decrease (P .05) at 12 months from 3.77 ± 1.28 mm to 2.30 ± 1.02 mm. Conclusion: PADM in conjunction with MCAT may be successfully utilized for the treatment of Miller Class I, II, and III multiple adjacent GR. Keywords: clinical study, coronally advanced tunnel, gingival recession, porcine acellular dermal matrix, root coverage

Objective: This prospective pilot study investigated differences in changes in oral-health-related quality of life (OHRQoL) depending on the prosthetic treatment type (rigidity). Method and Materials: Sixty participants seeking prosthetic treatment were included. The following data were collected before (T1) and 4 weeks after completion of prosthetic treatment (T2): OHRQoL (OHIP-G14) and dental status, categorized in terms of rigidity of the denture as fixed dental prosthesis (FDP, maximal rigidity), removable partial denture prosthesis (RPD, medium rigidity), or complete dentures (CDs, minimal rigidity). After prosthetic treatment, there were three groups of 20 participants: group 1, change in dental status to less rigid; group 2, equally rigid; group 3, more rigid restorations. Data were evaluated using nonparametric statistical test methods and power analysis. The minimally important difference (MID) of two OHIP-G14 units was determined to be clinically relevant. Results: At T1, 20 participants had FDP, 18 RPD, and 22 CD; at T2, 10 had FDP, 37 RPD, and 13 CD. Overall, average OHIP-G14 values improved clinically relevantly and statistically significantly (P .001) with treatment. OHRQoL improved more in group 3, with a median of 8 (IQR 14.75; P = .002), than in group 2, with 2.5 (IQR 9.5; P = .033), or group 1, with 4.5 (IQR 16.5; P = .116). Applying MID, all groups improved clinically significantly. Compared to groups 1 and 2, group 3 improved clinically more significantly. Conclusion: OHRQoL improved with prosthetic treatment. A patient-customized treatment regime seems as important as prosthesis type (rigidity). Keywords: OHIP-G14, oral-health-related quality of life, prosthetic restoration, treatment effect

Objective: The aim of this retrospective study was to evaluate medium-term marginal peri-implant bone loss following placement of root-form implants featuring a micro-threaded rough-surfaced neck and a platform-switched implant-abutment connection. Method and Materials: Records were identified of patients treated with such implants over a 3-year period at three Italian dental centers. Patient radiographs were digitized and subjected to computerized analysis of peri-implant bone resorption. Results: Records of 112 patients who received 257 implants were analyzed. Although implant diameters and lengths varied, all had a 0.3-mm platform-switching width and a 2.5-mm high micro-threaded neck. All patients healed uneventfully, and no peri-implant infection, implant mobility, or radiolucency around the implant were detected at any follow-up control. At the 72-month control (average 71 ± 5 months) all implants were successful according to Albrektsson and Zarb's criteria. At implant level, average peri-implant bone resorption was 0.18 ± 0.12 mm at 6 months, 0.22 ± 0.15 mm at 12 months, 0.23 ± 0.16 mm at 24 months, 0.25 ± 0.17 mm at 36 months, 0.26 ± 0.15 mm at 48 months, and stable at subsequent controls, regardless of the implant diameter and length. At patient level, a similar trend was observed, with crestal bone loss stabilizing from 48 months onward. Conclusion: The surface, geometry, and platform-switching features of the implant under investigation allowed effective bone preservation on a medium-term basis. Keywords: implant, marginal crest bone, micro-thread, platform switching, rough surface

Objective: To evaluate the effect of a new chlorhexidine-fluoride varnish on mutans streptococci (MS) counts and laser fluorescence (LF) readings in fissures of permanent molars. Method and Materials: The study group consisted of 57 healthy schoolchildren (7 to 14 yrs) that volunteered after informed consent. A double-blind split-mouth design was employed and 87 pairs of non-cavitated permanent molars were randomly assigned to treatments with either chlorhexidine-fluoride varnish (CHX-F) or chlorhexidine-thymol varnish (CHX-T, Cervitec Plus) as active control. The varnishes were topically applied at baseline and every sixth week throughout the 24-week study period. Endpoints were MS counts (CRT test) and occlusal LF readings (DIAGNOdent pen) registered regularly during follow-up. Results: At baseline, > 50% of the occlusal fissures harbored high MS counts (? 105 CFU), but a significant decrease (P .05) was found after treatment with both varnishes. After 24 weeks, less than 5% exhibited high counts. There were no significant differences between the varnishes at any time point. The mean LF values were similar in both treatment groups at baseline, but a significant reduction (P .05) was scored in the CHX-F group after 12 and 24 weeks. A similar reduction was found also in the CHX-T group after 24 weeks. No adverse events were reported. Conclusion: There were no significant differences between the CHX-F and CHX-T varnishes in terms of MS suppression after four applications over 24 weeks. Both varnishes also reduced the LF readings significantly compared with baseline, but further long-term studies are needed to confirm a caries-preventive effect. Keywords: caries, chlorhexidine, dental varnish, fluoride, laser fluorescence, mutans streptococci

A variety of periodontal plastic surgical techniques have been proposed to obtain root coverage of gingival recession defects. All of the available root coverage procedures are able to provide significant root coverage for Miller Class I and II recession-type defects. However, only the subepithelial connective tissue graft in conjunction with a coronally advanced flap appears consistently effective across all clinical parameters, and is therefore currently considered the gold standard for gingival recession therapy. The major shortcomings of connective tissue graft procedures include patient morbidity associated with the second surgical site and limited availability of palatal donor tissue. More recently, 3D collagen matrices of human and porcine origin have been introduced as possible alternatives to autogenous connective tissue grafts in recession coverage procedures. This paper aims to give an overview on the possible use of collagen matrices as soft tissue substitutes and a possible alternative to connective tissue grafts in the surgical treatment of gingival recession defects. Keywords: 3D collagen matrices, acellular dermal matrix, collagen, connective tissue grafts, gingival recession coverage

Intraosseous metastatic tumors (IOM) in maxilla are less frequent than the soft tissue metastatic tumors. Lung and bronchogenic metastatic tumors are uncommon in the maxilla. We present a maxillary bronchogenic metastasis with a rare clinical appearance. IOM was misdiagnosed as a dentoalveolar abscess and treated with antibiotics for 3 weeks. After not responding to antibiotics, the patient's general dental practitioner forwarded the patient to the Department of Oral and Maxillofacial Surgery. The associated tooth was extracted and the patient was recalled 1 week later. No signs of improvement were observed, and cytology, biopsy, and radiology diagnostics were performed. Cytologic results and biopsy could not differentiate a metastatic tumor from a salivary duct carcinoma. Ultimately, negative androgen receptors immunohistochemistry supported the diagnosis of bronchogenic metastatic adenocarcinoma. This case report stresses the importance of taking a thorough medical history. To our knowledge, this is the third bronchogenic IOM to the maxilla reported, mimicking a dentoalveolar abscess. General dental practitioners are among the first in contact with oral metastatic tumors and it is therefore important to report unusual clinical cases, as they present a diagnostic challenge for both the clinician and the pathologist. Keywords: lung adenocarcinoma, maxilla, metastasis, misdiagnosis

Leukemia is a malignant neoplasm of hematologic origin occurring from disorganized proliferation or increased life span of white cells. The initial manifestations of leukemia are generally signs of bone marrow failure, such as pallor, fatigue, fever, bleeding, and infection related to peripheral blood cytopenias. Few reports have described osteonecrosis, especially in the femoral head, as an initial manifestation of acute lymphoblastic leukemia. To the best of our knowledge, osteonecrosis of the jaw has not been reported as a first sign of leukemia. Here, two cases of osteonecrosis of the jaw as an initial manifestation of acute leukemia are reported, as well as a review of the literature regarding the main oral manifestations of leukemia. Keywords: acute lymphoblastic leukemia, first symptom, oral cavity

Objective: To compare the pain experienced by patients during injections of local anesthesia in the palate using the traditional syringe and the controlled flow technique with the Calaject system. Method and Materials: A single-blind, split-mouth, randomized controlled trial was performed. Twenty-five volunteers were recruited in the Dental Hospital of the University of Barcelona, Spain. Each participant received two injections (0.3 mL of mepivacaine 3%), one with the traditional syringe (control side) and another with the Calaject system (experimental side), both during the same session. Pain intensity was evaluated after each injection with a 100-mm visual analog scale (VAS). A descriptive and bivariate statistical analysis was made. Results: The mean pain experienced was 44.8 mm (standard deviation [SD] 19.0, range 8-72) with the traditional injection and 28.8 mm (SD 19.7, range 8-72) with the Calaject system (P .001). Moderate/severe pain was more frequently referred in the control side (68%) in comparison with the experimental side (28%). Conclusion: Given the parameters of this study's design, the injection of local anesthetics in the palatal area with the Calaject controlled-flow system seems to reduce pain, in comparison to the use of a traditional syringe. Keywords: Calaject system, computer-delivery anesthesia, dental anesthesia, local anesthesia, pain