Quintessence International, 07/2015

Objective: The number of available CAD/CAM systems has dramatically increased in recent years. Consequently, although clinical data for the newer systems are missing, in vitro studies are published frequently. The goal of this review was to provide an overview of in vitro studies conducted with the Procera system. Method and Materials: Repeated online searching in PubMed was done until June 2014 using the search terms Nobel, Procera, dental, implant. Papers reporting clinical studies, evaluating cementation procedures as well as investigations using norm-shaped test specimens were excluded from analysis. Data were then assigned to the following categories: material characterization, scanner technology, single crown and multi-unit restorations, passivity of fit of implant-supported restorations, and implant abutments. Results: Relative comparisons within specific studies based on the control specimens used indicate that all Procera restorations meet clinical requirements. Absolute comparisons between studies are not possible due to great variations in study design and outcome measures. Conclusion: While the relevance of in vitro data is frequently questioned, practicing clinicians have to rely on such information when judging the applicability of a novel CAD/CAM system. Given that the Procera CAD/CAM system has proven its reliability both in vitro and in clinical use, existing in vitro data for this CAD/CAM system may serve as a useful reference providing benchmark values for future developments. Schlagwörter: CAD/CAM, in vitro, Procera

Objective: The purpose of this article was to review the literature on the properties of chlorhexidine (CHX) and the adverse effects that may occur from its use in endodontics. In addition, adverse effects that may result from its use, such as dark staining of teeth, chemical interaction with sodium hypochlorite and formed flocculate, biologic hazards, and interactions with the filling material were evaluated. Data Sources: Relevant publications on the use CHX in endodontics were thoroughly reviewed from the literature published between the years 2007 and 2014. Method and Materials: The authors conducted an electronic search using the English language databases Medline and PubMed. Results: According to the reviewed studies, it was concluded that CHX has proven antimicrobial activity, excellent substantivity, low surface tension, and low cytotoxicity and genotoxicity that depend on the dose and exposed area. There is scientific evidence showing the possibility of tooth staining and formation of brown precipitate when its use is associated with sodium hypochlorite. On the other hand, it is not well established that its use interferes with the quality of endodontic fillings. With respect to the biologic risks, the degradation of CHX may generate para-chloroaniline and free radicals, which are harmful to the vital tissues. There is no established consensus on the potential risk of CHX. Conclusion: The final considerations of this review will encourage researchers to seek scientific evidence demonstrating the safety of the use and applicability of CHX in endodontic therapy. Schlagwörter: chlorhexidine, endodontics, properties, root canal therapy

Objective: The cementation of fixed dental prostheses (FDPs) on implants involves the risk of undetected excess cement. If a zinc oxide-eugenol cement (ZEC) is used as the luting material, this risk appears to be lower, as the excess cement will dissolve in the peri-implant sulcus. However, using a ZEC on a general basis conflicts with the manufacturers' classification of a ZEC as a temporary luting material. To evaluate the clinical safety of ZECs, the present study investigated whether more ZECretained reconstructions than screw-retained reconstructions loosen over time. Method and Materials: In a retrospective observational study, the frequency of FDP loosening was investigated. For this purpose, data from patients who had been fitted with FDPs on two or more than two posterior implants were investigated. The study compared screw-retained (n = 59) vs cement-retained (n = 40) FDPs on implants over an observation period of 3.5 years after reconstruction incorporation. All cement-retained FDPs had been cemented with a temporary ZEC. Results: The prevalence of reconstruction loosening was significantly lower for cement-retained FDPs when a ZEC (10%) was used than it was for screw-retained FDPs (29%); four screw-retained FDPs and one cementretained FDP developed major complications. The survival rate of the reconstructions within the observation period was 97% for screw-retained FDPs and 100% for cement-retained FDPs (not significant). Conclusion: The prevalence of cementretained FDP loosening was significantly lower than that of screw-retained FDPs. Cementing FDPs on implants using a temporary cement does not necessarily lead to a higher number of loosened reconstructions. Permanent cementation with ZEC appears to be justified. Schlagwörter: cement-retained, fixed dental prostheses, loosening, screw-retained, TempBond

Objective: The aim of this investigation was to evaluate the performance of Straumann Bone Level SLActive implants in various clinical situations in daily dental practice for up to 3 years. Method and Materials: This was a prospective, multicenter, non-interventional study in which implants were placed within approved indications in any situation deemed suitable by the treating clinician. No implant placement or loading protocol was specified, and implants were placed according to the routine treatment protocols at each participating center. Results: In this analysis, data were available from 342 implants in 233 patients in three countries (USA, Canada, and Switzerland). One or two implants were placed in the majority of patients (70.8% and 19.3%, respectively), mostly in the maxilla (71.3%); almost half (47.7%) were placed in the esthetic zone. Implant placement after 4 to > 16 weeks of healing was preferred in Switzerland (92.0%), while 42.0% of implants were placed immediately in the USA and Canada. A flapless procedure was performed in 25.2% of cases in the USA and Canada, compared to 0.5% in Switzerland. Cumulative implant survival and success rates after 3 years were 97.5% and 93.5%, respectively. Conclusion: Straumann Bone Level Implants can achieve favorable outcomes and high survival rates after 3 years in daily dental practice. The survival and success rates were comparable with those achieved in formal controlled clinical trials. Schlagwörter: bone level implant, daily dental practice, implant success, implant survival, non-interventional study, SLActive

Objective: To investigate five orthodontic procedures, namely separator placement, banding, initial arch wire ligation (0.016 NiTi), T-loop activation, and use of intermaxillary elastics with respect to intensity of peak pain, time of peak pain, need of medication for pain relief, and effect on routine life due to pain. Method and Materials: One hundred patients (52 males, 48 females) selected for comprehensive orthodontic therapy were included in the study. They were divided into five study groups, namely the separator group, banding group, initial NiTi group, T-loop activation group, and intermaxillary elastics group. Each patient was given a previously prepared questionnaire regarding the following: time of peak pain, intensity of peak pain, need for analgesic consumption, and effect on routine life. Results: Consumption of medication for pain relief was found to be highest in the separator and the initial NiTi groups. Routine life was affected most in the intermaxillary elastics and the initial NiTi groups, but it was not statistically significant. Statistically significant differences were found between the T-loop activation and the banding groups and also between the banding and the intermaxillary elastic groups with respect to perception of intensity of peak pain. In the separator group, the time of peak pain was experienced at the 24th hour and in the rest of the groups it was at the 6th hour with most patients, although the values were not statistically significant. Conclusion: Peak pain intensity varies from one procedure to another. It was significantly more due to T-loop activation and wear of intermaxillary elastics than banding. Schlagwörter: orthodontics, pain, T-loop, visual analog scale

Objective: The aim of this study was to evaluate the radiographic and histomorphometric results of two different xenografts in bilateral sinus augmentation in patients with posterior maxillary atrophy. Method and Materials: Eight patients with less than 5 mm residual alveolar bone height were included in this study. One side was augmented with bovine bone graft-1 and the other side with bovine bone graft-2. Radiographic analyses were performed before and after augmentation, and before the implant placement. After 8 months of healing period, bone biopsies were obtained during implant placement. Results: No statistically significant difference was found between the groups, based on post-augmentation and pre-implantation graft heights (P > .05). Histomorphometric evaluation demonstrated 24.63% and 29.13% newly formed bone in the graft-1 and graft-2 groups, respectively. Intergroup differences were not significant for the mean percentage of new bone formation (P > .05). Conclusion: Within the limitations of this study, it can be concluded that xenograft materials resulted in satisfactory bone height and trabecular new bone formation, and they could be used for the rehabilitation of atrophic maxillae. Schlagwörter: clinical study, deproteinized bovine bone, histology, sinus floor augmentation

Osteonecrosis of the jaw (ONJ) is associated with the use of bisphosphonates (BPs), denosumab, and antiangiogenic drugs; however, the pathophysiology of medication-related ONJ (MRONJ) remains unknown. Recent advances in therapies for diseases that affect bone remodeling have led to the development of agents that inhibit the receptor activator of nuclear factor-kappa B ligand (RANKL). One such inhibitor is denosumab, a highly specific, fully human immunoglobulin G2 monoclonal antibody against RANKL. We report a case of ONJ that developed following dental extraction in a patient treated for metastatic colorectal cancer with denosumab. At the first medical examination at our hospital, her clinical presentation was indistinguishable from stage 2 MRONJ, classified according to the 2014 American Academy of Oral Medicine position paper. Discontinuation of denosumab was directed by her oncologist, and we prescribed oral antibiotics and irrigated the exposed area of bone. Seven months after denosumab cessation, the sequestrum of the anterior part of the mandible was naturally shed and the site was healed. Denosumab and BPs have significantly different mechanisms of action. The effects of denosumab on bone turnover are more rapid and reversible than those of BPs. Discontinuation of denosumab may be effective in the management of denosumab-related ONJ, depending on the primary tumor control. Schlagwörter: denosumab, discontinuation of drug, osteonecrosis of the jaw (ONJ)

Objective: The purpose of the present case report is to document the removal of a radix in antro without a hemorrhagic complication in presence of a posterior superior alveolar artery (PSAA) with a 2.8 mm diameter following a radiographic 3D planning by cone beam computed tomography (CBCT) scan. Furthermore, a brief literature overview on studies describing the existence and the variance of the PSAA is provided. Method and Materials: A foreign body removal in the right maxillary sinus was performed on a 33-year-old healthy man by using the lateral window osteotomy. The preoperative CBCT scan showed three arteries in the lateral maxillary sinus wall at a distance of 24.6 mm, 19.5 mm, and 13.5 mm to the alveolar crest. Results: By removing a foreign body out of the maxillary sinus a vessel with a diameter of nearly 3 mm was exposed. Due to CBCT scan planning and the use of piezosurgery it was possible to avoid any damage to the vessel during the operation. The postoperative healing was uneventful and no complications occurred. Conclusion: Although laceration of vessels with a large diameter during lateral window osteotomy is not life-threatening it may compromise visualization and reduces the surgical outcome. Therefore, 3D imaging is recommended for the minimization of intra- and postoperative complications and for the localization of any foreign body in relation to other anatomical structures. This is of special interest in case of anatomical variances of blood vessels. Schlagwörter: complications, cone beam computed tomography, lateral window osteotomy, maxillary sinus, posterior superior alveolar artery, radix in antro, vascularization

Bad breath is a widespread but still largely taboo problem. The dentist is often the first point of contact for affected patients. Initially, the diagnosis and quantification of halitosis provides objective evidence and helps to find the underlying causes, but it is equally important for monitoring the treatment progress. Most often, halitosis is caused intraorally, thus the dentist will also be responsible for initiating an appropriate treatment. Apart from the simple organoleptic examination without the need for additional instruments, several devices for the measurement of halitosis are available which provide a differentiated analysis of the exhaled air by determining and quantifying the detected volatile sulfur compounds. Schlagwörter: bad breath, halitosis, halitosis measurement, respiratory gas analysis, tongue coating, volatile sulfur compounds