Quintessence International, 04/2018

Objective: The goal was to investigate the clinical value of two-dimensional radiographs and different radiographic measurement techniques before instrument removal with a microsonic technique. The aim was to find an easy-to-use technique for predicting the success of removal and case evaluation. Additionally the quality of root canal filling after instrument removal was assessed. Method and Materials: This retrospective study analyzed patients' records and preoperative and postoperative periapical radiographs made using the paralleling technique. On preoperative radiographs, canal access angle and Schneider and Weine angle of root canal curvature were measured and compared. The Schäfer method was used for measuring the radius of curvature. In cases of successful removal taper, homogeneity and length of obturation were evaluated on postoperative radiographs. Results: A total of 123 cases of instrument removal were investigated. In total, 97 fragments (78.9%) were removed successfully. Statistical analysis was performed with Pearson's chi-square and Fisher's exact test (α .05). The site of fragment relative to canal curvature, canal access angle, and Schneider angle significantly influenced the success of removal. The highest chance of removal failure was associated with > 20 degrees of canal access angle and > 40 degrees of Schneider angle. Only 26.3% of obturations met all technical standards. Altered taper could be identified in 64.2% and was always associated with ledge formation. Conclusion: Microsonic removal is a successful method to retrieve separated instruments. The use of only one radiographic measurement technique is not sufficient to precisely evaluate root canal anatomy, case difficulty, and chance of successful removal before instrument removal on a periapical radiograph. Postoperative root canal fillings are mainly substandard. Schlagwörter: angle of curvature, canal curvature, instrument removal, microsonic technique, radius of curvature

Objective: The aim of the present prospective clinical study was to assess the survival rate and the radiologic crestal bone level alteration around four interforaminal immediately loaded narrow-diameter implants (NDIs) in the edentulous mandible. Method and Materials: A total of 20 participants received each 4 NDIs (MDI, 3M Espe; diameter 1.8 mm, length 13 or 15 mm) in the edentulous mandible. Immediate loading was performed if insertion torque was 35 Ncm or higher. The implants were loaded the same day by converting the existing full denture into an implant overdenture. Follow-up visits were performed five times (baseline to 52 weeks). Standardized radiographs were taken at baseline and 12, 26, and 52 weeks post-loading. Clinical parameters (Plaque Index, probing depth, bleeding on probing) were assessed. The nonparametric ANOVA test was used to assess crestal bone level changes. Results: In all 20 patients the healing of the total 80 implants was uneventful and no implant was lost. Sixty-eight (85%) implants were loaded immediately. All clinical parameters showed healthy, stable, and well-maintained peri-implant soft tissue conditions. The mean (± standard deviation) radiographic bone loss after 1 year was 0.78 (± 0.64) mm. Conclusion: According to the 1-year results of this prospective clinical study, NDIs seem to be a reliable alternative to support prostheses in edentulous patients with a reduced horizontal mandibular bone volume. Schlagwörter: bone loss, edentulism, immediate loading, mandibular overdenture, narrow-diameter implants

Objective: Fracture of osseointegrated dental implants is the most severe mechanical complication. The aim of the present study was to analyze possible causative factors for implant body fracture. Method and Materials: One hundred and one patients with 218 fitted implants and a follow-up period of 3 to 10 years were studied. Factors associated with biomechanical and physiologic overloading such as parafunctional activity (eg, bruxism), occlusion, and cantilevers, and factors related to the planning of the dental prosthesis, available bone volume, implant area, implant diameter, number of implants, and their inclination were tracked. The impact of their effect was analyzed using the Bonferroni-corrected post-hoc Mann-Whitney test for each group. Results: The incidence of dental implant fracture was 2.3% in the investigated cases. Improper treatment planning, bruxism, and time of the complication setting in were the main factors leading to this complication. Typical size effect was established only for available bruxism, occlusal errors, and their activity duration. These complications were observed most often with single crown prostheses, and in combination with parafunctional activities such as bruxism and lack of implant-protected occlusion. Conclusion: Occlusal overload due to bruxism or inappropriate or inadequate occlusion as a single factor or a combination of these factors during the first years after the functional load can cause implant fracture. Fracture of the implant body more frequently occurred with single crowns than with other implant-supported fixed dental prostheses. Schlagwörter: bone resorption, bruxism, implant complications, implant fracture, occlusal load

Traumatic dental injuries are reported to have a high prevalence regardless of the region or the age group. Concussion injuries are considered as moderate, but very frequent injuries. They are associated with a wide spectrum of pulpal reactions. Pulp canal obliteration in spite of negative sensitivity proves ongoing pulp vitality. This case report presents multiple traumatic dental injuries in both maxillary central incisors with two different pulpal reactions during a follow-up period of 4 years in a healthy 7-year-old girl. The initial trauma with a concussion required no invasive treatment. Three days later, the child presented again with a new dental trauma. At the follow-up appointments after 3, 4, 6, 12, and 18 months, the traumatized teeth were functional and asymptomatic, but the radiograph after 1 year showed partial obliteration in the coronal part of the maxillary right central incisor. After 4 years, the periapical radiograph showed complete apical closure, and increase in root length and dentin thickness for both maxillary central incisors, with almost complete root canal obliteration in the right central incisor, whereas the left central incisor showed no signs of obliteration. Thus, this case showed different pulpal reactions to traumatic dental injury and that the loss of clinical sensitivity of the obliterated tooth does not automatically mean the loss of vitality and the need for endodontics. Regular follow-ups are essential in concussion cases to observe the pulp vitality and root formation. Schlagwörter: concussion, obliteration, pulp, root canal, trauma

Objective: To evaluate the clinical performance of impedance spectroscopy, laser fluorescence, and bitewing radiographs in detecting occlusal caries and compare them with visual scores. Method and Materials: In 62 adults, one occlusal surface per person was selected and independently examined by two examiners using the visual ICDAS scoring system, CarieScan PRO (ACIS), DIAGNOdent pen (LF-pen), and bitewing radiographs. The procedures were repeated within 1 to 4 weeks. The diagnostic performance was expressed as sensitivity, specificity, predictive values, accuracy, and diagnostic odds ratio (DOR) using ICDAS as gold standard. Intra- and inter-examiner reproducibility was assessed with intra-class correlation coefficients (ICC) for numerical results and kappa values for categorical data. Five patients dropped out due to no-shows or restorative care. Results: In total, 54% of the teeth had early or no lesions (ICDAS 0 to 2) while 46% exhibited moderate to extensive lesions (ICDAS 3 to 5). The Spearman correlation coefficients were 0.65, 0.60, and 0.71 for ICDAS vs ACIS, LF-pen, and bitewing radiographs, respectively. ACIS demonstrated high specificity and positive predictive values but low sensitivity, whereas LF-pen had moderate sensitivity and high specificity. Accuracy and DOR was highest for bitewing radiographs. The ICC values ranged between 0.65 and 0.88 for ACIS and 0.89 and 0.94 for LF-pen. The weighted kappa values were 0.81 to 0.91 for ICDAS and 0.90 to 0.92 for bitewing radiographs. Conclusion: All three methods were useful for detecting occlusal caries but bitewing radiography exhibited the best performance when compared with visual scoring. ACIS displayed the highest specificity and positive predictive value but the sensitivity was low and the clinical handling was less convenient. Further clinical studies are needed to evaluate the long-term effects of early caries detection on dental health. Schlagwörter: adults, caries detection, ICDAS, impedance spectroscopy, laser fluorescence, radiographs

For the past several thousand years, until development of the titanium dental implant, only a few missing teeth were replaced successfully in a very small number of individuals. Nowadays, placement of dental implants has become sufficiently commonplace that there is a need to interchange information between what we know about periodontal health and disease and what we know about health and disease involving dental implants. This review discusses the similarities and differences between teeth and dental implants with regards to anatomy, biology, physiology, and pathologic processes. The concept of biologic width is discussed in the context of interaction of periodontal and peri-implant tissues with microbial products produced by periodontal biofilms. The periodontal microbiome is discussed as networks of organisms interacting not only with periodontal and peri-implant tissues, but also with each other as networks of competing organisms. Overall, the transfer of biologic knowledge from what we know about peri-implantitis and what we know about periodontitis should help to develop new directions for biologic understanding about both health and disease of teeth and dental implants. Schlagwörter: bone, bone loss, gingival health, plaque

In dentistry, methods for determining age and the degree of dental and skeletal development play an important role, in particular in the assessment of developmental disorders of the dentition as well as in the planning of orthodontic interventions. Dentistry is also important in the field of forensics due to the possibility of age determination based on the dentition. In addition to anthropometric and morphologic methods, numerous biochemical, histologic, radiologic, and radiation-free imaging methods exist to determine the chronologic, but also dental and skeletal age of a person or a patient. This article aims to provide an overview of the currently available methods for age determination in dentistry, both for forensic and diagnostic-therapeutic purposes, and to critically assess their indication and value based on the available evidence. Schlagwörter: anthropometry, chronologic age, dental age, radiology, skeletal age

Objective: A trend towards increasingly new forms of dental practice has been observed in the FDI World Dental Federation. Elementary foundations such as the free dentist and therapy choice, and independent, free, self-responsible professional practice may be undermined. The current study is aimed at analyzing the general training framework, organization, and professional types of dental practice in the European Regional Organization (ERO) zone and at critically discussing selected aspects of changes in the dental profession. Method and Materials: A questionnaire was developed by the ERO Working-Group "Liberal Dental Practice." Information about dental schools, professional organizations, dental practice regulations, and ambulatory healthcare centers was analyzed. Results: Self-employed dental practice is the most common type of practice (51.7%). Dentists are allowed to work independently immediately after graduation (72.7%). Approximately one-third are organized as compulsory members in chambers/corporations. The density of dentists has a mean of 1,570 inhabitants per dentist. In most countries, there are no special rules for founding dental ambulatory healthcare centers. In a total of 353 universities of the ERO countries surveyed, 16,619 dentists per year were trained, with a trend toward a higher percentage of female students (63%). Conclusions: Despite modern forms of dental practice, the charter of the individual liberal dental profession (CED et al, 2013) should be respected and taken into account on the basis of ethical principles. The commercialization of the dental profession can be neutralized only by establishing and following well-defined ethical principles; oral healthcare quality can thus be ensured without the influence of third parties. Schlagwörter: Europe, liberal dental practice, modern forms of occupation, oral health policy, trends in dental occupation