PubMed-ID: 31994534Seiten: 16-42, Sprache: Englisch
Noncarious cervical lesions (NCCLs) involve the loss of hard tissue from the cervical areas of teeth through processes unrelated to caries. NCCLs are nowadays a common pathology caused by changes in lifestyle and diet. The prevalence and severity of cervical wear increase with age. It is generally accepted that the lesions are not generated by a single factor but result from a combination of factors. Among the factors proposed to be related to the formation and progression of NCCLs are biocorrosion (erosion), friction (abrasion), and possibly occlusal stress (abfraction). The clinical appearance of NCCLs can vary depending on the type and severity of the etiologic factors involved. Practitioners should follow a checklist to achieve an accurate diagnosis of the etiology of multifactorial NCCLs.
The successful prevention and management of NCCLs require an understanding of the etiology and risk factors, including how these change over time in individual patients. The decision to monitor NCCLs rather than intervene should be based on the progression of the lesions and how they compromise tooth vitality, function, and esthetics. Treatment options include techniques to alleviate dentin hypersensitivity and the placement of an adhesive restoration, eventually in combination with a root coverage surgical procedure. An adhesive restoration is considered the last treatment option for NCCLs.
Based on their excellent esthetic properties and good clinical performance, there is a general indication to place composite restorations for NCCLs. The clinical performance of these restorations is highly product-dependent, particularly regarding the adhesive system used. The type of composite material seems to have no significant influence on the clinical performance of NCCL restorations in clinical trials. It is much more important that the operator carries out the clinical procedure correctly.
Marginal degradation is frequently seen during aging. Yearly maintenance with the eventual repolishing of the restoration margins will lengthen the lifespan of the restorations.
PubMed-ID: 31994535Seiten: 44-54, Sprache: Englisch
Objective: The present study was undertaken to determine the tooth whitening effectiveness of trays with no reservoirs (Invisalign aligners or Vivera retainers used as bleaching trays), initially with a finite element analysis (FEA) and subsequently with a clinical study using spectrophotometry.
Materials and methods: The FEA technique was used to determine the ideal distribution of bleaching gel between teeth and aligners in vitro. Three sample areas of gel application on the maxillary central incisors (the incisal edge, the middle part, and the gingival edge) were analyzed. Spectrophotometry was used to ascertain the clinical effectiveness of the bleaching gel as it related to the results of the FEA. More specifically, the chromatic variation obtained by the bleaching gel on teeth 41 and 32 (control teeth, with reservoirs) was compared with that on teeth 31 and 42 (study teeth, without reservoirs).
Results: The FEA results showed that the optimal gel distribution is reached when 2 mm3 of gel is applied to the center of the vestibular face of the tooth in the tray. As regards the clinical study, there were no relevant differences of whitening effectiveness between the teeth with reservoirs and those without. In both cases, the whitening was effective and the patients were completely satisfied with the results.
Conclusions: The advantages for patients to receive dental bleaching during orthodontic treatment with aligners are evident. The procedure is not time consuming and requires less financial expense. Further clinical studies are required to assess the effectiveness of the procedure.
PubMed-ID: 31994536Seiten: 56-67, Sprache: Englisch
Harvesting good-quality connective tissue grafts (CTGs) is important in periodontal surgery. Compared with CTGs, free gingival grafts (FGGs) have a slower healing process and higher donor site morbidity. As far as graft quality and anatomic limitations are concerned, deepithelialized free gingival grafts (DE-FGGs) are superior to CTGs. In the current study, a modified combined approach is proposed that aims to address the disadvantages of conventional FGG harvesting methods. This approach entails harvesting a thin and narrow DE-FGG, repositioning the epithelial layer, and applying a plastic stent. The outcomes of this improved method indicate fast healing at the donor sites, fewer postoperative complications, and better esthetic results at the recipient sites.
PubMed-ID: 31994537Seiten: 68-91, Sprache: Englisch
Periimplantitis in a malpositioned maxillary anterior implant is one of the most challenging situations in implant dentistry. Since the regenerative treatment can often be unpredictable and have esthetic consequences such as soft tissue recession due to flap raising, extraction is sometimes recommended. In order to place a new implant after extraction, a bone regeneration procedure must be carried out. This implies raising a flap and therefore the risk of further interproximal gingival recession. In the case presented in this article, a hopeless implant at position 11 presented severe periimplantitis and soft tissue recession, which also affected the mesial part of tooth 12. Tooth 21 had a root canal treatment and a crown. After the implant extraction, a minimally invasive simultaneous bone regeneration and soft tissue graft procedure was performed to reconstruct the remaining ridge using xenograft, a collagen membrane, and a connective tissue graft (CTG). Ten months later, in order to improve the ridge profile, an augmentation procedure was carried out using a CTG. Three months later, an implant was placed and immediately loaded. Three months after loading, the right lateral incisor that still presented a mesial gingival recession was slowly extruded by orthodontic treatment until the papilla was symmetrical to the contralateral one. At the end of the orthodontic extrusion, an implant-supported crown was placed at position 11 and a tooth-supported crown delivered in place of tooth 21. A composite restoration was performed on tooth 12. One year later, the soft tissue level was almost symmetrical at incisor level and the periimplant bone level at implant 11 was stable.
PubMed-ID: 31994538Seiten: 92-106, Sprache: Englisch
Objective: The aim of this study was to create mathematical modeling to generate statistical models that reliably and quickly identify facial type while smiling. This analysis enables the creation of a digital design for the prosthetic restoration of the anterior teeth.
Materials and methods: The study involved the computer analysis of 91 facial images. Through mathematical modeling, digital facial maps were generated consisting of 27 landmark points and 12 basic lines determining the facial type. Four main facial types were defined for the purposes of this study: strong, dynamic, delicate, and calm. Selected data were recorded in a database and analyzed using IBM SPSS Modeler software.
Results: A varying number of combinations characterize the face; 61.5% of people have the features of two facial types, and 38.5% of three facial types. The overall analysis of the data for both genders shows the most accurate model for predicting facial type by digital facial map is the created algorithm C5.1 (classification tree), with a general prediction accuracy of 84.3%.
Conclusion: Dental Anatomical Combinations with Rebel Simplicity systems is a constructive way to ensure harmonious unity between the teeth and the facial type. Digital facial maps provide reliable and fast identification of the facial type while smiling. This analysis enables the creation of a digital design for the prosthetic restoration of the anterior teeth.
PubMed-ID: 31994539Seiten: 108-117, Sprache: Englisch
Post and core fabrication is important in the restoration of endodontically treated teeth. Significant coronal and radicular dentin destruction commonly occurs in endodontically treated teeth. As a result, preserving all the remaining tooth structure is imperative in order to improve the prognosis of the restorative treatment. Core height and width need to be carefully designed and built in order to receive the final restoration. Direct free-hand composite resin core buildup in increments may be a challenging and time-consuming procedure in the dental chair. The case report presented in this article describes a clinical technique using a clear matrix to receive composite resin injections in order to achieve an ideal shape and core size.