Rehabilitation of severely worn teeth: A systematic review

Minimally invasive prosthodontics using the concept of prosthetically guided orthodontics

OBJECTIVE

This case report aims to present how digital technology can be employed to plan the orthodontic movement of teeth into their final positions for prosthodontic rehabilitation. An interdisciplinary approach to treatment planning and the result of prosthodontic treatment involves the cooperation of an orthodontist and a prosthodontist. When planned to achieve optimal results for a minimally invasive and functional prosthodontic treatment, orthodontic pretreatment provides superior esthetic results and favorable long-term success.

CLINICAL CONSIDERATIONS

The orthodontic movements of the teeth were planned so that the prosthodontist could reconstruct an optimally functional and esthetic occlusion while preserving the hard dental tissues. The orthodontic pretreatment minimized the need to prepare the teeth, avoiding any mucogingival surgery to improve the gingival architecture.

CONCLUSIONS

In complex clinical cases, it is essential to evaluate the advantages of an orthodontic pretreatment before starting a prosthodontic treatment. This pretreatment can help preserve dental tissues, reduce or eliminate the need for surgical intervention, and achieve long-term stability and esthetic results.

CLINICAL SIGNIFICANCE

This case clearly shows the benefits of orthodontic pretreatment for prosthodontic outcomes. With modern digital tools, such an orthodontic pretreatment should become standard clinical practice when planning a complex clinical case.

Tooth Wear Evaluation System 2.0-Evaluation of diagnostic reliability in the assessment of signs and symptoms for tooth wear by non-experts

BACKGROUND

Tooth wear is a multifactorial condition that manifests through various signs and symptoms. These individual signs and symptoms were described in multiple studies, leading to the inclusion in TWES 2.0 (Tooth Wear Evaluation System 2.0) and the forthcoming DC-TW (Diagnostic Criteria for Tooth Wear). However, a study evaluating their reliability has yet to be conducted.

OBJECTIVE

The aim of the study was to examine the reliability in the assessment of 6 signs of pathological tooth wear and 18 clinical signs and symptoms determining aetiology, all of which are included in the TWES 2.0/DC-TW.

METHODS

48 dental students (operators) evaluated patient cases from a patient pool of 14 patients on dental casts and high-resolution intraoral photographs. The agreement between all operators for each sign and symptom was calculated based on ICC (Intraclass Correlation Coefficients). Additionally, the agreement of each operator's evaluation with a predefined sample solution was calculated based on Cohen's kappa.

RESULTS

Inter-user agreement ranged from near perfect (0.91) to poor (0.02) for the various pathology signs or aetiology symptoms of tooth wear (mean 0.32). The agreements of the operator's ratings compared to the sample solution resulted in Cohen's kappa from 0.18 to 1 (mean 0.59) for the pathology signs and ranged from 0.02 to 0.51 for the aetiology signs (mean 0.38).

CONCLUSIONS

The reliability of the signs and symptoms examined and the ability of individual investigators to correctly identify and assign signs and symptoms varied widely. The current assessment tools for the qualification of tooth wear need further refinement, and examiners need intensive training in tooth wear assessment.

Digital superimposition of scans for recording and transferring vertical relation from provisional restorations when rehabilitating worn-out dentition: A dental technique

Excessive wear of the natural dentition results in the loss of tooth anatomy and the vertical dimension of occlusion (VDO) which may necessitate full mouth rehabilitation. Successful full-mouth rehabilitation with increased VDO requires accurate recording and transfer of the newly raised VDO with provisional restorations. Conventional bite registration can incur errors during the recording and transfer of vertical dimensions. This article introduces a digital approach-the superimposition of scans using an intraoral scanner (IOS) to transfer VDO, occlusion, and aesthetic data from provisional restorations for designing and fabricating indirect restorations in the management of worn-out dentition.

Clinical longevity of direct and indirect posterior resin composite restorations: An updated systematic review and meta-analysis

OBJECTIVES

To answer the PICO(S) question: Is there a difference in clinical longevity between direct and indirect resin composite restorations placed on permanent posterior teeth?

DATA

Randomized controlled clinical trials (RCTs) investigating direct and indirect resin composite restorations in posterior permanent teeth were considered.

SOURCES

Several electronic databases were searched, with no language or date restrictions. The revised Cochrane Collaboration's tool for assessing risk of bias (RoB-2) was used to analyze the studies; meta-analyses were run and the certainty of evidence was assessed by the GRADE tool. A subgroup meta-analysis was performed for resin composite restorations placed on posterior worn dentition.

STUDY SELECTION

Twenty-three articles were included in qualitative synthesis, while 8 studies were used for meta-analyses. According to the RoB-2 tool, 5 studies were ranked as "low risk", 7 had "some concerns", while 11 papers were rated as "high risk" of bias. There were no statistically significant differences in short-term (p = 0.27; RR=1.54, 95% CI [0.72, 3.33]), medium-term (p = 0.27; RR=1.87, 95% CI [0.61, 5.72]) and long-term longevity (p = 0.86; RR=0.95, 95% CI [0.57, 1.59]). The choice of restorative technique had no influence on short-term survival of resin composite restorations placed on worn dentition (p = 0.13; RR=0.46, 95% CI [0.17, 1.25]). The certainty of evidence was rated as "very low".

CONCLUSIONS

Direct and indirect resin composite restorations may show similar clinical longevity in posterior region, regardless of the observation period or substrate (wear-affected and non-affected dentition). The very low quality of evidence suggests that more long-term RCTs are needed to confirm our results.

SURVIVAL AND COMPLICATION RATES OF RESIN COMPOSITE LAMINATE VENEERS: A SYSTEMATIC REVIEW AND META-ANALYSIS

OBJECTIVES

The aim of this systematic review was to evaluate the survival and complication rates of resin composite laminate veneers.

METHODS

Randomized controlled trials and cohort studies with a minimum 2-year follow-up assessing survival and complication rates of resin composite laminate veneers on permanent dentition from 1998 to May 2022. Literature searches were conducted in MEDLINE (PubMed), Scopus, and the Cochrane Central Register of Controlled Trials electronic databases. References cited in the related reviews and included full-text articles were also hand-searched to further identify potentially relevant studies.

RESULTS

A total of 827 articles were identified. Twenty-two studies were considered for full-text review after the title and abstract screening stage. After exclusion, 7 studies (3 randomized controlled trials and 4 cohort studies) were included in the systematic review. Three published scales were adopted for the quality and risk of bias assessment. At the survival rate threshold, the overall heterogeneity (I2) for randomized controlled trials was 50.5% (P = .108). The overall pooled survival rate of the randomized controlled trials was 88% (95% CI: 81%-94%), with the mean follow-up time ranging from 24 to 97 months. Surface roughness, color mismatch, and marginal discoloration were the most reported complications.

CONCLUSION

Resin composite laminate veneers demonstrated moderately high survival rates for the entire sample and the direct laminate veneer group demonstrated higher survival rates than the indirect approach. Most of the complications were regarded as clinically acceptable with or without reintervention.

Advances in Preventive and Therapeutic Approaches for Dental Erosion: A Systematic Review

This review discusses both preventive measures and clinically implemented therapy procedures that have been developed recently for the prevention and treatment of tooth erosion.

METHODS

The databases PubMed, Scopus, and Web of Science were used for a thorough search. Studies on the prevention and treatment of dental erosion that were conducted in English and used in vitro were among the inclusion criteria.

RESULTS

The search turned up 391 papers in total, with 34 of those publications matching the requirements for inclusion. Varnishes, toothpastes, and solutions containing fluoride and other substances were used as preventive measures.

CONCLUSIONS

Dental erosion is a significant issue, and taking preventative steps is crucial to lessening the disease's spread and its effects. Interventions based on fluoride seem to be successful at halting erosion and encouraging remineralization. To effectively address severe tooth erosion, therapeutic methods, including composite restorations, prosthetic crowns, and veneers, are available. Dental erosion causes aesthetic and functional issues that are best addressed with less invasive treatments like direct composite restorations. To improve and broaden the range of available treatments for this common dental issue, additional research and development are required.

Longevity of Anterior Composite Restorations for Localized Tooth Wear: A Scoping Review

(1) Objective: This scoping review evaluates composite restorations as a treatment modality for anterior tooth surface loss and investigates the longevity of the direct and indirect composites used herein. (2) Method: The search encompassed Medline, Embase, Web of Science, the Cochrane Library, and hand search utilizing the PICO framework. (3) Results: Eight studies were included in this review, comprising one randomized controlled trial, one retrospective, and six prospective studies. Some studies reported favorable outcomes for composite restorations in anterior teeth. Although not statistically significant, evidence supported the anterior composite as a viable short- to medium-term solution for managing tooth wear. Direct resin composites were deemed clinically and cost-effective when managing localized anterior tooth wear. However, limitations and inconsistencies in this scoping review limited definitive clinical recommendations. (4) Conclusions: Further research, including well-managed randomized controlled trials using standardized protocols and longer follow-up periods, is essential to reconfirm the long-term efficacies of anterior composite restorations when managing tooth wear. A robust research design and exacting protocols could facilitate more meaningful clinical conclusions.

Risk factors of tooth wear in permanent dentition: A scoping review

BACKGROUND

Tooth wear (TW) prevalence is high and increasing and has important consequences on the patient's quality of life. Knowledge of risk factors is crucial to promote diagnosis, prevention strategies and timely interceptive treatment. Many studies have identified TW risk factors.

OBJECTIVE

This scoping review aims to map and describe suspected available factors associated with TW in permanent dentition based on quantitative measurement.

METHODS

The scoping review was conducted using the PRISMA extension of the Scoping Reviews checklist. The search was conducted in October 2022 from the Medline® (PubMed® interface) and Scopus® databases. Two independent reviewers selected and characterised the studies.

RESULTS

2702 articles were identified for assessment of titles and abstracts, and 273 articles were included in the review. The results show a need to standardise TW measurement indices and the study design. The included studies highlighted various factors, classified into nine domains: sociodemographic factors, medical history, drinking habits, eating habits, oral hygiene habits, dental factors, bruxism and temporomandibular disorders, behavioural factors, and stress. Results related to chemical TW (erosion) risk factors underline the importance of eating disorders, gastroesophageal reflux and lifestyle, particularly drinking and eating behaviours, which supports developing public health information campaigns and interventions. Besides chemical, this review identifies evidence of several mechanical TW risk factors, such as toothbrushing and bruxism; the influence of this last factor needs to be further explored.

CONCLUSIONS

TW management and prevention require a multidisciplinary approach. Dentists are in the first line to detect associated diseases such as reflux or eating disorders. Consequently, practitioners' information and guideline diffusion should be promoted, and a TW risk factors checklist (the ToWeR checklist) is proposed to help diagnostic approaches.

Conservative and cost-effective rehabilitation of a deep bite patient with worn dentition: A case report of the Dahl technique approach

The reformation of teeth with severe wear is a real challenge for clinicians. Through a clinical case study, this case illustrates a minimally invasive approach using the Dahl technique and bonded restorations for the treatment of a worn dentition with a loss of vertical dimension of occlusion and restoring ideal aesthetics.

The longevity of tooth-coloUred materials used for restoration of tooth wear: an evidence-based approach

Patients with tooth wear are commonly encountered in general dental practice. When indicated, restorative rehabilitation is often accompanied by a request from the patient for an aesthetic, tooth-coloured outcome. This article seeks to provide an evidence-based approach, focussing on the longevity of the materials which can be used for the restorative treatment of tooth wear, as well as their modes of failure and observed performance.

Total Rehabilitation Using Adhesive Dental Restorations in Patients with Severe Tooth Wear: A 5-Year Retrospective Case Series Study

INTRODUCTION

Currently, there is little clinical evidence to support the medium- and long-term survival and clinical performance of ultraconservative approaches using adhesive restorations in full-mouth restorations. The aim of this case series study was to evaluate the medium-term clinical performance of anterior and posterior adhesive restorations applied with direct and indirect techniques using resin composites and glass-ceramic-based materials.

MATERIALS AND METHODS

The inclusion criteria were an esthetic problem as the main reason for consultation and severe generalized wear of grade 2 to 4 according to the Tooth Wear Evaluation System (TWES 2.0). In addition, at each follow-up appointment, patients were required to submit a clinical-parameter-monitoring record according to the modified United States Public Health Service (USPHS) criteria.

RESULTS

Eight patients with severe tooth wear were treated through full rehabilitation in a private dental clinic in Spain by a single operator (AFC). A total of 212 restorations were performed, which were distributed as follows: 66 occlusal veneers, 26 palatal veneers and 120 vestibular veneers. No signs of marginal microleakage or postoperative sensitivity were observed in any occlusal, vestibular and/or palatal restoration after the follow-up period. The estimated survival rate of the 212 restorations was 90.1% over 60 months of observation, with a survival time of 57.6 months. Only 21 restorations had complications, which were mostly resolved with a direct composite resin. The dichotomous variables of the restoration type (posterior veneer, anterior veneer) and the type of restored tooth (anterior, posterior) were the risk predictors with statistically significant influences (p < 0.005) on the survival of the restorations.

CONCLUSION

According to the results of this study, there is a significantly higher risk of restorative complications in posterior teeth compared to anterior teeth. Also, it can be concluded that the indication of adhesive anterior and posterior restorations is justified in the total oral rehabilitation of patients with severe multifactorial tooth wear, as they are associated with a low risk of failure.

Bruxism as a new Risk Factor of Musculo-Skeletal Disorders?

OBJECTIVES

Musculoskeletal disorders (MSDs), particularly neck and low back pain, constitute a major public health issue worldwide with a heavy morbidity and economic impact. However, the relationships between the stomatognathic system and MSDs are subjected to debate, data sorely lacking. The study objective was to investigate the association between bruxism (BR) and MSDs. Secondary objective includes the study of the association between tooth wear (TW) and MSDs.

METHODS

This is a cross-sectional study on 425 participants frequenting a university dental clinic. The presence of MSDs was evaluated with the standardized Nordic questionnaire. The sleep and awake BR assessments were based on clinical examination and self-report. TW was measured with the BEWE index. Socio-demographic factors, medical history, life habits and stress were analyzed as potential confounding variables.

RESULTS

91% of patients reported at least one MSD during the preceding 12 months and 78.8% were diagnosed as bruxers. In multivariate analyses, BR was associated with a 5-fold increased risk of prevalent MSD (OR=5.88 (2.7-12.5), p<0.0001). Regarding TW, for a one-point increase in anterior BEWE score, the risk to present an MSD was increased by 53% (OR=1.53 (1.12-2.08), p=0.0076). Moreover, BR was independently associated with neck, shoulder, upper back, low back, hip & thigh and knee MSDs. Anterior TW was independently associated with neck, low back and hip & thigh MSDs, and global TW with knee MSDs.

CONCLUSIONS

BR and TW were shown to be associated with MSDs. The cause-and-effect relationships between those factors needs to be analyzed to optimize prevention and therapeutic care.

CLINICAL SIGNIFICANCE

Results suggest that the body is a whole, a balanced muscular system, where every part constitutes a link of the chain. MSDs management and prevention may require a multidisciplinary team approach and future perspectives include defining the dentist's role in this context, particularly with respect to BR diagnostic and treatment.

Indications for the use of direct composite restorations in the management of tooth wear

The increasing prevalence of tooth surface loss has been widely reported. Patients present with varying degrees of tooth wear and consideration is given to whether a prevention and monitoring approach, or a treatment and restoration approach, is appropriate. A missed diagnosis or excessively prolonged monitoring risks progression to the detriment of a successful outcome, with the potential compromise on the quality and quantity of tooth structure available for predictable adhesive dentistry. Direct composite resin (DCR) restorations can be considered as a viable treatment option for all extents of tooth wear, including cases that have progressed to a severe degree. This paper aims to review the indications for DCR restorations in the management of tooth wear, using clinical cases to demonstrate their effectiveness.

Managing tooth wear with respect to quality of life: an evidence-based decision on when to intervene

Patients with more severe forms of tooth wear may require restorative rehabilitation. The decision to commence treatment must be taken carefully and there are a multitude of factors to consider. Alongside the clinical signs and symptoms typically associated with tooth wear, there is also the need to assess the impact of the condition on the patient's oral health-related quality of life. As part of the discussions relating to the attainment of informed consent for the restoration of the worn dentition, not only is it relevant to appropriately appraise the risks, benefits, costs, reasonable alternatives and likely prognosis of the proposed treatments, but to also elaborate on the expected impact of the intervention on the patient's oral health-related quality of life. The aim of this article is to review the evidence relating to the impact of the quality of life with the management of tooth wear, with the introduction of the concept of an evidence-based approach to decision-making when planning care.

Wear behaviour of direct composite restorations in tooth wear patients: a 5-year clinical study

OBJECTIVE

This study aimed to investigate the wear behaviour of direct composite restorations after 5 years and associated patient factors.

METHODS

38 patients (6 females, 32 males; 35.2 ± 7.6y) from the Radboud Tooth Wear Project with generalized moderate to severe tooth wear were treated with direct composite restorations on all teeth. Ethical approval was sought and granted before the study was undertaken. Intraoral 3D scans were recorded at 1 month (baseline) and 5 years (recall) after treatment. The amount of height loss was measured at six index teeth (first molars and upper central incisors). Patient factors (age, vertical dimension of occlusion increase, bite force, aetiology score, jaw position and bearing/ non-bearing cusps) were included in the analysis. Multilevel multiple regression with bootstrapping was used to analyse the influence of these factors on wear behaviour of restorations. Observer reliability was tested by paired t-tests and Band-Altman plots (p<0.05) RESULTS: After 5 years, the mean height loss was 0.23± 0.19 mm for incisors and 0.43± 0.24 mm for molars (p≤0.001). Patient factors did not show any significant influence on height loss of the composite restorations, while bearing cusps showed significant more wear compared to non-bearing cusps (p≤0.001). The observer reliability tests confirmed the repeatability (correlation of 0.809, DME 0.103).

CONCLUSIONS

Wear of composite restorations is a significant and relevant factor over time in patients treated with severe tooth wear. Within the limitations of this clinical study, patient factors were found not to have a significant effect on wear behaviour of direct composite restorations.

Tooth Wear Epidemiology and Its Associated Periodontal Health and Sociodemographic Factors in a Cluster of Senior Citizens in Northern Greece

Tooth wear (TW) is an irreversible and cumulative phenomenon causing aesthetic and functional compromise. Increasing wear has been associated with age, and various other factors have been reported to influence its type and/or severity both in individuals and groups. Increased TW may constitute a major future problem for the elderly. The present cross-sectional study aims at determining the prevalence of TW in senior citizens from Northern Greece and evaluating the patient-level associations between TW, periodontal condition, and sociodemographic factors. A sample of 363 dentate individuals, aged between 65 and 74 years, was considered according to the WHO guidelines for national pathfinder surveys and three different dentists examined the representative population groups from different urban and rural areas in Northern Greece. The examiners were calibrated prior to the survey, with an interexaminer agreement of over 85%. The simplified TWI, community periodontal index (CPI), attachment loss (AL), plaque index (DI), calculus index (CI), and sociodemographic factors were detected and measured. TW is very prevalent among senior citizens in Northern Greece, with males having been found to experience more wear. Age and oral health status, when measured by the periodontal indices AL, DI, and CI, are significantly combined with TW in both urban and rural areas.

Three-Dimensional Finite Element Analysis of Worn Molars With Prosthetic Crowns and Onlays Made of Various Materials

Background/Purpose

Restoration of worn teeth represents a challenge for practitioners in terms of preserving dental tissues, achieving restoration requirements, and choosing the most appropriate material. This study aimed to evaluate the effect of both preparation and restoration type on stress distribution in modeled first mandibular molars when functional and parafunctional occlusal forces were applied.

Materials and methods

The study sample consisted of 40 three-dimensional computer models of restored lower first molars with full crowns (gold, nickel-chrome, lithium disilicate, BruxZir® zirconia, and porcelain fused to metal) and onlays (gold, nickel, chrome, lithium disilicate, and direct and indirect composites). Forces of different intensities and directions were applied, and then finite element analysis was carried out based on the von Mises equivalent stress theory to predict the failure that could occur in the restoring materials and luting cement or bonding agent.

Results

In functional forces groups, zirconia crowns showed the lowest value of the failure risk, while the highest value was in veneering porcelain with values close to the rest of the models. For onlays, gold onlays represented the best stress distribution with the lowest value of the failure risk, in contrast to the composite onlays that had the highest failure risk. In parafunctional forces groups, the preference remained for zirconia and gold crowns, as well as for metal onlays, with greater differences in the values of the failure risk.

Conclusion

Gold alloy exhibited better behavior in the stress distribution. All restorations showed similar behavior when applying functional forces; however, when applying parafunctional forces, both gold and zirconia crowns have shown the best results.

Treatment of Tooth Wear Using Direct or Indirect Restorations: A Systematic Review of Clinical Studies

Tooth wear is considered a well-developed issue in daily clinical practice; however, there is no standard protocol for treatment. The aim of this manuscript was to systematically review the literature to evaluate the clinical outcomes of direct or indirect restorations for treating tooth wear. A literature search was conducted through the PubMed MedLine, Scopus, ISI Web of Science, Scielo, and EMBASE databases up to 29 April 2022. Clinical studies evaluating the clinical performance of direct or indirect restorations for treating tooth wear for a minimum follow-up of 6 months were included in the review. A total of 2776 records were obtained from the search databases. After full-text reading, 16 studies were included in the qualitative analysis. Considering the high heterogenicity of the studies included, a meta-analysis could not be performed. All studies included the rehabilitation of anterior and posterior teeth with extensive wear, using both indirect and direct restorations for a maximum follow-up of 10 years. Restoration materials included ceramo-metal crowns, full gold crowns, lithium disilicate ceramic, zirconia, polymer infiltrated ceramic networks, and resin composites. Most of the reports assessed the survival rate of the restorations and the clinical features using the United States Public Health Service (USPHS) Evaluation System criteria. Contradictory discoveries were perceived concerning the type of restoration with better clinical performance. Considering the current literature available, there is no evidence in the superiority of any restoration technique to ensure the highest clinical performance for treating tooth wear.

Acid Resistance of CAD/CAM Resin Composites

Acid resistance of CAD/CAM resin composites. Erosion-related tooth surface loss is closely related to acid exposure, such as contact with acidic beverages or disease-related reflux. As a result, dental restorations in affected patients are also exposed to acids, which indicates that the performance and longevity of a dental restoration is impacted by the acid resistance of the individually employed restorative materials. However, unlike for ceramic materials, the acid resistance of CAD/CAM resin composites is not commonly evaluated by the manufacturers, and no standardised test methods have yet been established. Against this background, the present in vitro study aimed to examine the long-term resistance of CAD/CAM resin composites (Brilliant Crios, Cerasmart, Grandio blocs, Lava Ultimate, Shofu Block HC) against three acidic media (tonic water, acetic acid, hydrochloric acid) as well as demineralized water and to investigate potential damage mechanisms. Changes in surface roughness (Sa) were detected by confocal laser scanning microscopy (CLSM), and changes in surface hardness were measured using Vickers hardness (HV). The damage mechanisms were analysed by scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS) and micro X-ray computer tomography (µXCT). For each material, few changes in either Sa or HV were identified for at least one of the different media; for Cerasmart, the sharpest deterioration in surface properties was observed. SEM–EDS revealed leaching of barium, aluminium, and titanium from fillers in a 2 µm zone on the rough but not on the polished surface of the specimen. Within the limitations of the current study, it can be concluded that polished CAD/CAM resin composites can be recommended for clinical use in patients with erosive conditions.

Crown Reconstruction of Erosive Wear Using High-viscosity Glass Ionomer Cement: A Case Report

The aim of this clinical report is to present a possible alternative treatment, with 24-month follow-up, for restoring tooth loss due to extensive erosive tooth wear. A 21-year-old male patient, complaining of intense sensitivity in the maxillary posterior teeth, and presenting severe wear on maxillary premolar and molar teeth due to gastroesophageal reflux, sought care in the university clinics. The planned treatment was to refer for medical treatment and perform restorations with the high-viscosity glass ionomer cement Equia Forte (GC Corporation, Tokyo, Japan), aiming to restore the dental anatomy and to consequently decrease the pain symptomatology. A silicone guide, obtained from a diagnostic waxing, was used during the restorative approach considering the patient's occlusion. After all the clinical steps of the restorative technique, an occlusal adjustment of restorations was performed. During monthly recalls up to 24 months, the treatment was stable and in service. In addition, the patient reported no pain and improved chewing, leading to a better quality of life.

Rehabilitation of Worn Dentition with Direct Resin Composite Restorations: A Case Report

The incidence of tooth wear has steadily increased in all Western populations during the past decades. A through-care strategy, extendable for a lifetime, has become crucial to prevent the extensive loss of sound dental structure and to make an eventual retreatment affordable in the long term. An interceptive treatment using resin composite materials and no-preparation approaches meets these requirements. Moreover, continual developments in digital dentistry makes possible to predict the treatment plan for the restorative rehabilitation of the mouth. The availability of digital resources allows clinicians to increase predictability for excellent esthetics and good functional results. This article provides a step-by-step description of a full-mouth additive rehabilitation achieved by employing digital workflows and direct resin composite restorations. A comprehensive functional and esthetic evaluation of the treatment is proposed and discussed.

Canine Rise Method: A Conservative Approach for Worn Teeth Rehabilitation with Different Adhesive Restorative Materials

Background

In this article, two cases with generalized dental wear and four cases with localized dental wear are reported. In some of the cases, the worn teeth were restored with direct composite techniques with no mock-up and articulator mounting according to the canine rise method. This method is used without any change in the intercuspation of posterior teeth without a muscle relaxation appliance. It introduces a stable occlusal condition that can alter neuromuscular reflex activity, leading to improvements in certain muscle pain disorders. It is also used to protect the teeth and supporting structures from abnormal forces that might create a further breakdown and/or tooth wear.

Methods

The first step of treatment in all the cases was a composite build-up for maxillary and mandibular canines to restrict and guide the horizontal and vertical jaw movements and create adequate space for restorations. The second step was the placement of direct or indirect restorations on upper and lower anterior teeth efficiently and accurately.

Results

This method enhanced the esthetic outcomes in a conservative approach with no reduction in tooth material or time-consuming treatments.

Conclusions

This technique can be suggested for the treatment of worn teeth in patients with Angle's Cl I and Cl II classifications of malocclusion based on the follow-up results. It is not applicable for the treatment of worn teeth in patients with Angle's class III because occlusion is reversed, and canine teeth do not have guidance role. Practical Implications. This method significantly reduces the overall treatment time, and additional steps are required to restore the worn-out teeth and/or occlusion using the canine rise method.

Adhesive Management of Anterior Tooth Wear in Combination with the Dahl Concept-A 27-Month Observational Case Series

Localized anterior maxillary tooth wear caused by erosion and attrition with loss of interocclusal space is difficult to manage. This observational case-series study reports six cases with worn anterior dentition treated with labial ceramic and palatal direct resin composite veneers at an increased vertical dimension of occlusion without restoration of unaffected posterior teeth. Thirty-six palatal direct veneers were made in six patients from a nanohybrid resin composite with the help of a wax-up-based template at an increased vertical dimension. After the complete re-establishment of posterior occlusion, 40 labial lithium-disilicate ceramic veneers were fabricated with a mock-up-guided method. The sandwich veneers were evaluated according to the United States Public Health Service (USPHS) criteria after a mean service time of 22.7 months. Re-establishment of posterior contacts as well as subjective patient satisfaction and function were evaluated. The overall success of the labial ceramic veneers was excellent. The quality of the palatal resin composite restorations was found to be good with predominantly "Alpha" scores. The marginal quality (11.1% and 33.3% of integrity and discoloration, respectively) and surface roughness (16.7%) showed small deteriorations indicated by "Beta" scores. The resin composite showed, in general, signs of wear facets which resulted in "Beta" scores in 44.4% of the cases. Posterior contacts re-established firmly within 4 weeks in all cases. Patient satisfaction with esthetics and function was high. The short-term outcome of this non-invasive treatment option is favorable and promising.

The Dahl Concept: Best Evidence Consensus Statement

PURPOSE

In a series of publications, Dahl and Krogstad promoted an orthodontic technique for the treatment of severe wear of the anterior teeth that reportedly could induce intrusion of the anteriors and extrusion of the posterior teeth to allow space to restore the worn anterior teeth. The purpose of this Best Evidence Consensus Statement was to evaluate the existing dental literature related to the Dahl Concept.

METHODS

A PubMed search limited to clinical studies, clinical trials, randomized controlled trials, systematic reviews, meta analyses, and journal articles, using the key words Orthodontics, Dahl appliance, Dahl concept and adult, revealed 11 citations, 9 of which were related. An additional 9 citations were culled from the reference lists in the aforementioned articles.

RESULTS

The 20 articles that met the initial search criteria were evaluated and rated. The literature largely focused on the restorative materials that are commonly used to apply the Dahl technique.

CONCLUSIONS

While there is low-level evidence from a few case series that demonstrated the ability to achieve enough space in the anterior region for the restoration of lost anterior tooth structure, there is no compelling evidence to support any theories as to how that space was achieved. In addition, there is no evidence to support the long-term stability of that position and the restorations. Negative position and restorative outcomes have been reported.

The PGO concept: Prosthetically guided orthodontics concept

OBJECTIVE

The aim of this case report is to present a novel digital approach of guiding orthodontics and periodontal surgery by creating interim restorations that represent the final shape of the teeth before starting the treatment.

CLINICAL CONSIDERATIONS

The patient presented with worn dentition, super-erupted maxillary and mandibular anterior teeth, and altered passive eruption, all this creating a gummy smile. Following a digital wax-up design, a digital orthodontic set-up, and the digital bracket bonding, temporary restorations, and bracket indirect bonding trays were fabricated. Restorations' cementation, bracket bonding, and periodontal surgery were performed the same day. After 14 months of orthodontic treatment, teeth were restored with final ceramic restorations. One year and 6 months was the total treatment duration.

CONCLUSION

Prosthetically guided orthodontic concept allows the use of digital technology to simulate the final outcome of the patient treatment before starting dental therapy. This technique not only improves the communication between specialists, it also reduces treatment time and increases precision and predictability.

CLINICAL SIGNIFICANCE

The prosthetically guided orthodontics (PGO) concept has the goal to start interdisciplinary therapy with a simulation of the final outcome. Giving the worn teeth their proper size through interim restorations prior to orthodontic therapy will guide the orthodontist from the beginning of the treatment and will improve communications between all the specialists. Through a digital approach, a digital wax-up and an orthodontic digital set-up the objectives of treatment can be established early on.

Adhesion to eroded enamel and dentin: systematic review and meta-analysis

OBJECTIVE

The aim of this systematic review and meta-analysis was to compare the bond strength between eroded and sound permanent enamel and dentin and to assess whether bonding performance (immediate and after aging) differs between etch&rinse and self-etch adhesives and can be improved by surface pretreatment prior to bonding.

METHODS

Electronic databases (PubMed, Scopus, Embase, Web of Science, CENTRAL, LILACS, BBO) were searched by two reviewers. Random-effect meta-analyses were performed to compare bond strength to sound and eroded dental hard tissues without and with surface pretreatment prior to bonding, respectively. The effect of adhesive mode (etch&rinse vs. self-etch) and aging (immediate vs. aged) was compared using subgroup analyses. Statistical heterogeneity was assessed using Cochran's Q and I²-statistic. Funnel plots and Egger's regression intercept tests were used to evaluate publication bias. Quality and risk of bias of included studies were also assessed.

RESULTS

Fourty-seven studies (45 in vitro, 2 in situ) were included in the systematic review and meta-analyses. Erosion impairs bond strength to dentin (p < 0.001; mean difference: -10.2 MPa [95%CI: -11.9 to -8.6 MPa]), but not to enamel (p = 0.260). Surface pretreatment measures removing or stabilizing the collagenous matrix can improve dentin bond strength (maximum mean difference: +12.4 MPa). Etch&rinse and self-etch adhesives did not perform significantly different on eroded enamel (p = 0.208) and dentin (p = 0.353). The majority of studies (32 of 47) presented a medium risk of bias.

SIGNIFICANCE

Data from in vitro and in situ studies showed that erosion impairs dentin bonding of etch&rinse and self-etch adhesives and makes surface pretreatment prior to bonding of composite restorations necessary.

Wear behavior of a microhybrid composite vs. a nanocomposite in the treatment of severe tooth wear patients: A 5-year clinical study

OBJECTIVE

This study aimed to compare the wear behavior of a microhybrid composite vs. a nanocomposite in patients suffering from severe tooth wear.

METHODS

A convenience sample of 16 severe tooth wear patients from the Radboud Tooth Wear Project was included. Eight of them were treated with a microhybrid composite (Clearfil APX, Kuraray) and the other eight with a nanocomposite (Filtek Supreme XTE, 3M). The Direct Shaping by Occlusion (DSO) technique was used for all patients. Clinical records were collected after 1 month (baseline) as well as 1, 3 and 5 years post-treatment. The maximum height loss at specific areas per tooth was measured with Geomagic Qualify software. Intra-observer reliability was tested with paired t-tests, while multilevel logistic regression analyses were used to compare odds ratios (OR) of "large amount of wear".

RESULTS

Intra-observer reliability tests confirmed that two repeated measurements agreed well (p > 0.136). For anterior mandibular teeth, Filtek Supreme showed significantly less wear than Clearfil APX; in maxillary anterior teeth, Clearfil APX showed significantly less wear (OR _material = 0.28, OR _{jaw position} = 0.079, p < 0.001). For premolar and molar teeth, Filtek Supreme showed less wear in bearing cusps, whereas Clearfil APX showed less wear in non-bearing cusps (premolar: OR _material = 0.42, OR _{bearing condition} = 0.18, p = 0.001; molar: OR _material = 0.50, OR _{bearing condition} = 0.14, p < 0.001).

SIGNIFICANCE

Nanocomposite restorations showed significantly less wear at bearing cusps, whereas microhybrid composite restorations showed less wear at non-bearing cusps and anterior maxillary teeth.

Randomized controlled trial on the performance of direct and indirect composite restorations in patients with severe tooth wear

OBJECTIVE

The study aimed to evaluate survival and failure behavior of Direct Composite Restorations (DRC) and Indirect Composite Restorations (ICR) on molars and anterior teeth, in a Randomized Controlled Trial (RCT).

METHODS

Patients with generalized severe tooth wear were included, and randomly assigned to one of 2 protocols: (1) DCR: All teeth were restored with directly applied micro-hybrid composite restorations (Clearfil AP-X, Kuraray) for load bearing areas and nano-hybrid composite restorations (IPS Empress Direct, Ivoclar Vivadent) for buccal veneers; (2) ICR: First molars were restored with indirect composite 'tabletop' restorations and maxillary anterior teeth were restored with indirect palatal veneer restorations (Clearfil Estenia C&B, cemented with Panavia F, Kuraray). Remaining teeth were restored directly. Restorations were evaluated after 3 years, focusing on clinical acceptability. Statistical analysis was performed using Kaplan Meier curves, Annual Failure Rates (AFRs), and univariate Cox regression analyses (p < 0.05).

RESULTS

41 patients (age: 36.6 ± 6.6y) were evaluated after 3 years (40.0 ± 2.2 m). 408 restorations on first molars and palatal veneers on maxillary anterior teeth were part of this RCT, with 220 DCRs and 188 ICRs. No differences in survival between treatment modality for palatal veneers for any failure criteria were found. Tabletop restorations on first molars showed a considerable higher failure rate for ICR compared to DCR (p = 0.026, HR: 3.37, 95%CI = 1.16-9.81).

SIGNIFICANCE

In this RCT, directly applied composite restorations showed superior behavior compared to the indirect composite restorations, when used in the molar region.

Clinical performance of direct composite resin restorations in a full mouth rehabilitation for patients with severe tooth wear: 5.5-year results

OBJECTIVES

To evaluate the 5.5-year performance of direct resin composite restorations, prescribed for patients with severe tooth wear, requiring full-mouth rehabilitation.

METHODS

A convenience sample of 34 patients were recruited to a prospective trial between December 2010 and June 2013. The participants were provided 1269 full-mouth direct resin composite restorations (Clearfil AP-X) by 5 experienced operators, using the DSO-technique. Treatment resulted in an increase in the vertical dimension of occlusion (VDO). Failure was assessed at three levels. Frequencies of failure were analysed using Kaplan Meier survival curves and the effects of the relevant variables calculated with a multifactorial Cox regression (p < 0.05).

RESULTS

Annual failure rates (for all levels of failure, 'Level 3- ') of ≤ 2.2% and ≤ 2.9% were respectively reported for the anterior and posterior restorations with a mean observation time of 62.4 months. The completion of an anterior restoration with the need for further appointments resulted in significantly more Level 2- & 3- failures. An evaluation of the performance of the premolar and posterior maxillary restorations showed significantly lowered risks of certain types of failures, compared to the molar and posterior mandibular restorations.

CONCLUSIONS

At 5.5 years, 2.3% of the overall restorations displayed catastrophic, (Level 1) failures. Molar restorations, posterior mandibular restorations and the anterior restorations requiring two further sessions for completion, were associated with significantly higher risks for failure.

CLINICAL SIGNIFICANCE

Direct resin composite can offer an acceptable medium-term option for the treatment of severe, generalized tooth wear; molar restorations may require higher maintenance.

The effect of pre-treatment levels of tooth wear and the applied increase in the vertical dimension of occlusion (VDO) on the survival of direct resin composite restorations

OBJECTIVES

To investigate the effects of the level of pre-treatment tooth wear and increasing the VDO on the performance of direct resin composite restorations for the rehabilitation of pathological tooth wear.

METHODS

Full-mouth (pre-treatment) grading was performed on digital greyscale scan records for 34 participants (35.3 ± 8.4 years) with signs of moderate-to-severe generalised tooth wear, using the Tooth Wear Evaluation System and the Basic Erosive Wear Examination. Each participant received full-mouth direct resin composite restorations, with increased VDO. The post-treatment increase in the VDO was determined. Recalls were planned after 1 month, and after 1, 3, and 5 years. Three 'levels' of restoration failure were described. The effects of the variables on the frequencies of restoration failure were calculated with a multivariable Cox regression, (p < 0.05).

RESULTS

1269 restorations were placed with a mean observation period of 62.4 months. Increasing the VDO by 1 mm significantly reduced the risks of all levels of anterior restoration failure (HR ≤ 0.62, p ≤ 0.025). A higher anterior BEWE surface score was associated with increased risks of Level 2- & 3- failures, (HR ≥ 1.29, p ≤ 0.019). Premolar restorations showed lower risks of Level 2- & 3- failure, compared to the molar restorations, (HR ≤ 0.5, p ≤ 0.005).

CONCLUSION

Levels of pre-treatment wear and the applied change in the VDO significantly affected failure risk.

CLINICAL RELEVANCE

Direct resin composite restorations for the rehabilitation of wear should be made as voluminous as possible, respecting the presenting biological, functional, and esthetic constraints.

Aesthetic Management of Erosive Tooth Wear in a Young Egyptian Swimmer: A Case Report

Background

Tooth wear can have a multifactorial aetiology which requires thorough patient assessment and aesthetic management.

Purpose

This case report discusses the management of a young, Egyptian swimmer complaining of tooth sensitivity associated with erosive tooth wear. Anterior teeth were restored using the injection molding technique, also known as the injectable composite resin technique, to overcome the patient’s complaint and enhance the aesthetics of compromised anterior teeth.

Patients and Methods

Thorough patient assessment was followed by impression taking, a diagnostic wax-up and intraoral mock-up fabrication for aesthetic, functional and biological verification. Upon the patient’s agreement on the proposed treatment, an injection molding technique was carried out.

Conclusion

The tooth loss pattern associated with erosive tooth wear in competitive swimmers showed a very characteristic presentation. Detailed patient history is imperative for successful assessment of the risk factors contributing to the condition and treatment planning in such cases. The use of injection molding technique for restoration of anterior teeth is a simple, straightforward and aesthetically pleasing alternative for patients with erosive tooth wear requiring direct composite veneers.

Treatment of Tooth Wear Associated with Reduced Occlusal Vertical Dimension Using Direct Composite Restorations and a Removable Prosthesis

Tooth wear is increasing in prevalence within the United Kingdom. Treatment of tooth surface loss can be daunting for both the clinician and patient. However, use of additive resin composite restorations is a minimally invasive treatment modality. This case illustrates the treatment of tooth surface loss in both the maxillary and mandibular arches with direct composites restorations using putty indices generated from a diagnostic wax-up recorded in centric relation. The tooth surface loss had resulted in reduced restorative space on the right hand side. The restorative treatment involved increasing the anterior vertical dimension, enabling the provision of a cobalt-chrome partial denture. This case shows the restoration of form, function and aesthetics using a reorganised occlusal approach.

Restoration of severe localized tooth wear with zirconia-reinforced lithium silicate: A case report

Tooth wear is becoming an increasingly common cause for referral to restorative dentistry departments in the UK. Often, these cases are treated with resin-bonded composite direct restorations in the first instance. This article presents a case of 23-year-old patient who was treated using zirconia-reinforced lithium disilicate restorations.

CPD/Clinical Relevance: In certain cases, indirect restorations can be considered a first-line treatment, based on the presentation and patient factors. Each case should be evaluated on its own merits and careful consideration should be given to the evidence base and its relevance.

Direct Composite Resin for the Management of Tooth Wear: A Systematic Review

BACKGROUND

This study systematically reviewed survival of direct composite to restore worn teeth.

MATERIALS AND METHODS

A comprehensive electronic search of databases sourced from Medline-PubMed, Embase, Cochrane Central, Scopus, Google scholar was performed on literature published between January 1990 and December 2018. Grey literature was also reviewed. Data extraction included sample size, number of composite restorations, operators, composite type, mean or total follow-up time and success rate expressed as either percent of successful restorations or median survival time (MST). Methodological quality was rated using the Joanna Briggs Institute appraisal checklist for case series. Studies on children, non-carious cervical lesions, cast and all-ceramic restorations, case reports and case series with <5 participants were excluded.

RESULTS

A total of 1563 studies were identified and 1472 were screened. Sixty-two full-text papers were assessed for eligibility which resulted in 10 studies that met inclusion criteria. These were mainly case series and assessed 3844 direct composite restorations placed in 373 patients mostly in hospital settings. Survival ranged from 50% to 99.3%. Methodological quality improved from the earlier studies and was rated low to moderate in 7 studies and good in 3. The funnel plot showed a low risk of publication bias but there was considerable heterogeneity (I²=97.7%). There was a non-significant weak negative association between age and survival (Spearman's rho=-0.12).

CONCLUSION

Qualitative evaluation of the studies proved difficult because of the nature of case series but reporting improved in the later studies. Despite the generally short duration of studies, small sample sizes in terms of patient numbers and composite restorations, the survival rates of direct hybrid composite resin in the short to medium term are acceptable and support their application for the restoration of worn teeth.

Biomechanical planning for minimally invasive indirect restorations

This paper explores the planning and execution of indirect partial-coverage restorations and will outline practical recommendations for maximising the outcomes for minimally invasive (MI) approaches to indirect restorations, with a special focus on vital teeth, endodontically-treated teeth and worn dentitions. Throughout the paper, the supporting evidence for each rationale for partial-coverage restorations will be considered, as well as the risks and benefits of adopting an MI approach to indirect restorations.

Orthodontic-assisted one step- no prep technique: A straightforward and minimally-invasive approach for localized tooth wear treatment using polymer-infiltrated ceramic network CAD-CAM prostheses

OBJECTIVES

To introduce a minimally invasive and simple ortho-pros approach for localized tooth wear treatment.

CLINICAL CONSIDERATIONS

Four patients with localized anterior and/or posterior tooth wear were treated. Occlusal analyses were performed, and localized wax-up or digital setup were designed based on estimated tissue loss. No-prep anterior and posterior partial-coverage polymer-infiltrated ceramic network (PICN, Vita Enamic) restorations (eg, palatal and occlusal veneers) were computer-aided designed and manufactured (CAD-CAM), tried in, and bonded in supraocclusion, creating a posterior open bite. Then, brief partial (three patients) or global (one patient, for anterior teeth alignment request) orthodontic treatment was performed to extrude the posterior teeth and re-establish posterior occlusal contacts. The orthodontic treatment duration was ~2 months for extrusion. Direct composites were performed to mask the labial finish line of palatal veneers. Clinical results were successful after a follow-up of 15, 21, 23, and 47 months, with 100% success rate of PICN anterior restorations and some minor chippings of borders of thin (0.2 mm) posterior occlusal veneers. Patient-reported outcomes were positive.

CONCLUSION

Orthodontic-assisted one step-no prep technique is an advantageous and straightforward evolution of the Dahl concept. PICNs exhibit several advantages in this interdisciplinary approach.

CLINICAL SIGNIFICANCE

New hybrid-ceramic CAD-CAM materials and a collaborative interdisciplinary approach support the evolution of the Dahl concept for conservative treatment of worn dentitions. The orthodontic-assisted one step-no prep technique is predictable, efficient, and well tolerated by patients and conserves tooth structure.

The one-step no-prep approach for full-mouth rehabilitation of worn dentition using PICN CAD-CAM restorations: 2-yr results of a prospective clinical study

OBJECTIVES

To prospectively evaluate the One-step No-prep treatment of full mouth-worn dentition, a minimally invasive and multidisciplinary approach using PICN CAD-CAM composite restorations without provisional phase.

METHODS

Seven patients (n = 192 restorations) with severe tooth wear were included. Patient data were recorded, and an occlusal analysis and a tissue-guided wax-up were realized. After replacement of old fillings, no-prep Vita Enamic restorations (posterior restorations and palatal veneers) were bonded within 24 h. Direct composites were performed to mask the buccal joint on anterior teeth. Maxillo-facial physiotherapy was performed. Restorations were evaluated following World Dental Federation criteria. Treatment influence on Oral-Health-Impact-Profile-49 (OHIP-49) score was assessed.

RESULTS

Tooth wear etiology was related to soft drink consumption and bruxism. Mean VDO increase was 5.09 ± 0.85 mm on the incisal pin. The mean restoration thickness on molars was 0.55 ± 0.21 mm, and the lowest was 0.11 mm. 2-year survival rate of restorations was 100 % and success rate was 93.5 %, with 11 minor chippings and one debonding. A significant improvement of the global OHIP-49 score was observed.

CONCLUSIONS

In this clinical study on high risk patients, PICN restorations, applied in a minimally invasive way, showed high survival and success rates after two years, while minor chipping of very thin occlusal borders constituted the most frequent complication. Moreover, the patient acceptance was good according to OHIP-49 in this multidisciplinary approach.

CLINICAL SIGNIFICANCE

The use of PICNs allows the development of no prep and simple treatment protocols of worn dentition. The absence of provisionals did not engender any problem, on the basis of the realization of an occlusal analysis, the support of a maxillo-facial physiotherapist, and the use of an easy-to-adjust restorative material.

Aesthetic Rehabilitation of a Patient with Bruxism Using Ceramic Veneers and Overlays Combined with Four-Point Monolithic Zirconia Crowns for Occlusal Stabilization: A 4-Year Follow-Up

Management of severe worn dentition in patients with bruxism is challenging as a result of the loss of tooth structure and occlusal vertical dimension, temporomandibular implications, tooth hypersensitivity, and masticatory or aesthetic impairment. This case describes the 4-year follow-up clinical evaluation of a full mouth tooth-supported rehabilitation made on a 66-year-old man with bruxism and tooth wear, with aesthetic complaints and compromised masticatory function. The prosthetic treatment was planned with a digital smile design and a mock-up technique for an aesthetic and minimally invasive approach using lithium disilicate pressed and layered veneers on anterior teeth, posterior CAD/CAM lithium disilicate overlays with facial coverage, and CAD/CAM monolithic zirconia crowns with facial feldspathic ceramic on maxillary and mandibular canines and first molars in order to ensure the occlusal stability at the increased occlusal vertical dimension. After 4 years of function, no complications were registered. The choice of an appropriate material for the rehabilitation of these patients is essential to improve treatment prognosis and should be guided by mechanical and aesthetical properties. The use of four-point occlusal stabilization with CAD/CAM high strength monolithic zirconia crowns combined with ceramic veneers and overlays appears to be a reliable treatment option that enhances aesthetics and minimizes the occurrence of ceramic fractures, ensuring the treatment prognosis and predictability.

Effect of zirconia polycrystal and stainless steel on the wear of resin composites, dentin and enamel

This study evaluated the effect of two antagonist substrates (Y-TZP/zirconia or stainless steel) on the wear rate and surface alterations of different composite materials and bovine tooth substrates (enamel and dentin). The wear rate of different composite materials (n = 20; two direct composite resins: HelioMolar - HM; Clearfil AP-X - CAP, three indirect composite resins: Estenia C&B - EST; Adoro - ADO; Sinfony - SFY, and one composite resin for direct/indirect restorations: Filtek Z250 - Z250), bovine enamel and dentin against two different antagonist materials (zirconia or stainless steel) into two mediums (two-body and three-body wear) were collected. After wear tests on ACTA wear machine, Scanning Electron Microscopy (SEM) analysis was performed to access the surface alterations. The wear data were evaluated by three-way ANOVA and Tukey post-hoc test (α = 0.05). The factors 'antagonist', 'medium', 'restorative materials', and the interaction of all factors grouped by two and integrated showed statistical significance on the wear rates. A two-body test depicted no difference among all composites and enamel for wear rate, while a three-body test depicted differences among composites directly related to the filler content: EST < Z250 = CAP < ADO = HM < SFY. Dentin always showed the highest wear rates and enamel the lowest rates. The presence of food bolus (three-body test) led to higher wear rates in comparison to an only aqueous medium (two-body test). SEM analysis showed that different materials present specific wear patterns, regardless of the medium and the antagonist considered. Differently from enamel, dentin substrate was intensively prone to wear, regardless of the antagonist/medium. Resin composite substrates presented intermediate wear rates, depending directly on their filler content (% in weight).

Use of Digital-Conventional Method for Managing a Patient with Severely Worn Dentition: A Clinical Report

Severe forms of attrition are frequently found in patients with no or insufficient posterior occlusal support. Management of such patients using fixed or removable prostheses is a complex procedure and is still a challenge for clinicians. The present clinical report describes step by step full mouth rehabilitation of a patient with severely worn dentition using computer-aided design/computer-aided manufacturing- (CAD/CAM-) generated wax patterns, milled zirconia frameworks, and fabrication of removable partial denture (RPD) abutments using a digital-conventional method. The results were satisfactory during 18 months of follow-up.

The One step-No prep technique: A straightforward and minimally invasive approach for full-mouth rehabilitation of worn dentition using polymer-infiltrated ceramic network (PICN) CAD-CAM prostheses

OBJECTIVES

To introduce a novel approach for full-mouth rehabilitation of severely worn dentition using polymer-infiltrated ceramic network (PICN) computer-aided-design and manufacturing (CAD-CAM) restorations, without tooth tissue preparation and provisional phase.

CLINICAL CONSIDERATIONS

Three patients with generalized tooth wear, suffering from dental pain, masticatory dysfunction, bruxism and neck and back pain, were selected and treated in collaboration with physiotherapists. Occlusal analyses were performed and full-mouth diagnostic wax-ups were designed on the basis of estimated tissue loss. Deficient direct restorations were replaced and low-thickness PICN (Vita Enamic) restorations (up to 0.2 mm) were CAD-CAM designed from wax-ups, milled, tried-in and then bonded within two consecutive days. To mask palatal veneers, either buccal direct composites or glass-ceramic veneers were later performed. An occlusal splint was realized. Clinical results were shown to be successful after a follow-up of 22, 18, and 13 months, respectively. The absence of provisional phase did not engender any inconveniences. Patient reported outcomes were very positive, showing a reduction in neck and back pain and a well-being increase.

CONCLUSION

The proposed protocol is particularly minimally invasive and straightforward compared to classical techniques. PICNs exhibit several advantages compared to other materials. Preliminary results of this multidisciplinary approach are promising but deserve further clinical research.

CLINICAL SIGNIFICANCE

The development of CAD-CAM technologies offers the possibility of improving treatment of severe worn dentition, reducing chairtime and need of tooth tissue preparation, and introducing a new class of composite materials (hybrid ceramics), which exhibit interesting properties for this indication. The influence of the proposed multidisciplinary approach, particularly the collaboration with physiotherapists, needs to be further explored with respect to treatment of associated symptoms, such as masticatory muscles hypertrophy and neck pain.

Minimally Invasive Adhesive Rehabilitation for a Patient With Tooth Erosion: Seven-year Follow-up

Tooth wear is a multifactorial condition of growing concern. In clinical practice, it is often a challenge for prevention and treatment since many etiological factors may be involved. This case report describes an esthetic rehabilitation of a young patient presenting tooth wear due to erosion. The etiological factor of this case was the patient sucking on lemons, an acidic fruit. The main complaint of the patient was the appearance of short maxillary incisors. The treatment involved orthodontic and restorative dentistry techniques. First of all, an orthodontic device was used to increase the vertical dimension of occlusion and create an adequate space for the direct restorations. The posterior teeth were restored with two direct composite resin techniques; the anterior teeth were then restored using a balanced occlusion. The seven-year follow-up of the case is presented. Replicas of the restorations were made and visualized under scanning electron microscopy up to the 12-month evaluation. In the clinical follow-up at seven years, maintenance of the results and restorations can be clearly seen.

Recent advances in understanding the fatigue and wear behavior of dental composites and ceramics

Dental composite and ceramic restorative materials are designed to closely mimic the aesthetics and function of natural tooth tissue, and their longevity in the oral environment depends to a large degree on their fatigue and wear properties. The purpose of this review is to highlight some recent advances in our understanding of fatigue and wear mechanisms, and how they contribute to restoration failures in the complex oral environment. Overall, fatigue and wear processes are found to be closely related, with wear of dental ceramic occlusal surfaces providing initiation sites for fatigue failures, and subsurface fatigue crack propagation driving key wear mechanisms for composites, ceramics, and enamel. Furthermore, both fatigue and wear of composite restorations may be important in enabling secondary caries formation, which is the leading cause of composite restoration failures. Overall, developing a mechanistic description of fatigue, wear, and secondary caries formation, along with understanding the interconnectivity of all three processes, are together seen as essential keys to successfully using in vitro studies to predict in vivo outcomes and develop improved dental restorative materials.