Surface Properties and Wear Resistance of Injectable and Computer-Aided Design/Computer Aided Manufacturing-Milled Resin Composite Thin Occlusal Veneers

OBJECTIVES

 This study was conducted to investigate the microhardness, surface roughness (Ra), and wear behavior of thin occlusal veneers (TOV) fabricated from different injectable composite materials and compare them to a Computer-Aided Design (CAD)/Computer-Aided Manufacturing (CAM) resin-based material.

MATERIALS AND METHODS

 A 1-mm occusal veneer preparation was done in a mandibular right second molar typodont tooth. The prepared model was duplicated to fabricate 32 replicas and divided into four groups (n = 8). Standard TOV were fabricated either indirectly from Cerasmart blocks, Cerasmart, GC (CS), or directly from Beautifil Injectable X, Shofu (BF), G-ænial Universal injectable, GC (GU), or SonicFill 2, Kerr (SF) using the injection molding technique. All the specimens were subjected to both thermomechanical cyclic loading (TMC) in a chewing simulator. Wear measurement was conducted by three-dimensional (3D) scanning of the veneered models before and after TMC, and the difference in the volume of the sample was recorded as the volumetric material loss due to wear. Ra before and after TMC and Vickers microhardness (VHN) of the tested materials were measured using standardized samples (n = 8). Representative samples from each group were investigated under a stereomicroscope and a scanning electron microscope.

STATISTICAL ANALYSIS

 One-way analysis of variance (ANOVA) was applied to detect the effect of material on VHN and wear. Two-way ANOVA was utilized to examine the impact of material and TMC on Ra. Multiple comparisons between the groups were conducted using Tukey's post hoc test (α = 0.05). The Pearson's correlation coefficient was used to determine the relationship between hardness and wear and between roughness and wear (α = 0.05).

RESULTS

 CS exhibited the highest mean VHN (p ≤ 0.001), followed by GU and SF which were statistically similar (p = 0.883) but significantly higher than BF (p < 0.001). After TMC, GU revealed the lowest Ra and volumetric wear (VW), followed by CS, BF, and SF (p < 0.5). A highly significant correlation existed between Ra and VW (p = 0.001, R 2 = 0.9803).

CONCLUSION

 The effect of TMC on the surface properties and wear resistance of the investigated TOV is material-dependent. GU injectable TOV are less influenced by TMC than CS milled TOV. In contrast, BF and SF demonstrated significant VW and Ra which might limit their clinical use as TOV.

Interdisciplinary management of an adult patient with significant tooth wear

Adult patients may present with compromised dentitions which require extensive oral rehabilitation. This case report shows the fulfilment of both functional and aesthetic treatment objectives for a patient with significant tooth wear through carefully planned interdisciplinary management. © 2022 Australian Dental Association.

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.

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.

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.

Vertical Bite Rehabilitation of Severely Worn Dentitions with Direct Composite Restorations: Clinical Performance up to 11 Years

Our aim was to evaluate the clinical performance of direct composite restorations placed in patients with severely worn dentitions at an increased vertical dimension of occlusion, after up to 11 years. One hundred and sixty-four teeth in 13 patients with severely worn dentitions had been reconstructed with either microhybrid (first cohort; n = 59) or nanofilled (second cohort; n = 105) composite restorations at increased vertical dimension of occlusion using a wax-up-based template-aided placement technique. From the dental records, information about repair and replacement of restorations was obtained. Patients were clinically examined after a mean follow-up time of 10.7 years (first cohort) or 5.2 years (second cohort) using United States Public Health Service (USPHS) criteria. Subjective patient satisfaction was also recorded using visual analogue scales (VAS). The overall quality of the restorations was good with predominantly 'Alpha' and 'Bravo' scores, respectively. Nanofilled composite showed less surface degradation and better margin qualities than microhybrid composite. Of the 59 restored teeth in the first cohort, 13 restorations showed unfavorable events after 10.7 years, of which ten could be repaired. In the second cohort, 23 of 105 restorations showed unfavorable events, which could all be repaired. VAS scores revealed high patient satisfaction with the treatment approach. In conclusion, direct composite restorations placed at an increased vertical dimension of occlusion show good clinical long-term performance in patients with severe tooth wear.

The effect of varying head tilt on the perceived color from composite resin and porcelain restorations: Simulating the effect of altering torque

INTRODUCTION

This study aimed to assess the effect of changes in tooth torque on the perceived color of composite and porcelain restorations.

METHODS

A total of 30 patients with previous composite restorations and 30 patients with porcelain restorations on lateral and central incisors were selected. To simulate the effect of dental torque change, we asked the patients to tilt their heads upwards and downwards to represent buccal and palatal crown torque, respectively. Photographs were taken in 3 different positions (natural head position, 15° upward tilt, and 15° downward tilt). A laser alignment tool was used to help with head positioning. Color was measured on the 3 principal axes of the Commission Internationale de L'Eclairage, L∗, a∗, and b∗ color space using Photoshop software (Adobe, San Jose, Calif), and color differences were calculated. The midpoint of the clinical crown, both mesiodistally and incisogingival, was selected as the point of measurement. A general linear model was used to analyze the significance of changes in each value of different tooth torques. A t test was used to compare color changes of 2 different incisors (central and lateral) and overall color differences in the 2 types of restoration.

RESULTS

Significant changes of the L∗ and a∗ values were found as a result of the change in head inclination, whereas b∗ values remained unchanged. It was found that buccal crown torque resulted in lighter and greener porcelain restorations. Composite restorations behaved similarly with the only difference being that the central incisors appeared bluer. Palatal crown torque resulted in a darker and redder porcelain restoration and a darker, redder, and yellower composite restoration. No significant differences were found between color changes in the central and lateral incisors. Furthermore, porcelain and composite restorations had similar color changes with alteration of head inclination.

CONCLUSIONS

Orthodontic changes of tooth torque alter the color perceived from composite and porcelain restorations.

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.

Advances in materials and concepts in fixed prosthodontics: a selection of possible treatment modalities

The introduction of adhesive techniques in combination with translucent restorative materials has greatly influenced treatment concepts in fixed prosthodontics. Modern production technologies offer access to new polymer materials that provide innovative pre-treatment options for complex prosthetic rehabilitations. Additionally, computer-aided design and manufacturing (CAD/CAM) provides access to new ceramic types and thus extends the range of indications for metal-free restorative options. With these developments, important changes of treatment concepts in fixed prosthodontics have occurred which affect the professional life of dental practitioners with a focus on prosthetic dentistry. This article gives an overview of the advances in selected fields of fixed prosthodontics and provides support in material selection for different kinds of indications, from single-tooth restorations to fixed dental prostheses.

Clinical performance of occlusal onlays made of lithium disilicate ceramic in patients with severe tooth wear up to 11 years

OBJECTIVES

Evaluation of survival and complication rate of monolithic occlusal onlays made of lithium disilicate ceramic used in patients with severe tooth wear up to 11years of clinical service.

METHODS

In a prospective non-randomized clinical study 7 patients (4 male, 3 female; median age: 44.3±6.56years old) were restored full mouth with a total of 103 adhesively bonded occlusal onlays made of lithium disilicate ceramic (IPS e.max Press, Ivoclar Vivadent, Schaan, Liechtenstein). All restorations were examined during annual recall visits using periodontal parameters according to the modified United States Public Health Service (USPHS) criteria: (a) marginal discoloration, (b) secondary caries, (c) marginal integrity, (d) surface texture, (e) restoration fracture, and (f) occlusal wear, rating with Alpha, Bravo and Charlie over an observation period up to 11years (68-139 months; median: 94.9±26.1 months). Data was statistically analyzed using the Kaplan-Meier estimation.

RESULTS

Monolithic lithium disilicate occlusal onlays presented a 100% survival rate. Four restorations within one patient (3.9%) presented marginal discoloration, one after 60 and three after 108 months (all rated Bravo). One restoration (1%) showed a marginal crack formation (technical complication) after 120 months, rated Bravo. No biological complication, debonding or secondary caries could be found and tested periodontal parameters showed excellent results.

SIGNIFICANCE

Based on the analyzed data up to 11years, monolithic occlusal onlays made of lithium disilicate ceramic can be considered as a reliable treatment option for full-mouth rehabilitations in patients with severe tooth wear.

[Tooth Erosions Associated with Gastroesophageal Reflux: Cause, Prevention and Restorative Therapy]

Tooth Erosions Associated with Gastroesophageal Reflux: Cause, Prevention and Restorative Therapy Abstract. Dental erosions are caused by the recurring contact of solutions which are unsaturated in tooth minerals,ith hard tooth substances. This initially leads to softening and later to an irreversible loss of hard tooth substance. Erosion is observed particularly with excessive consumption of acidic foods (e.g. soft drinks or citrus fruits) but also in connection with gastrointestinal (gastroesophageal reflux disease) or psychosomatic diseases (anorexia nervosa or bulimia nervosa). The aim of this article is to define dental erosions, their causes, prevalence and consequences as well as possible preventive measures. Based on a clinical example of a patient with reflux-related erosions, a therapy option with direct composite tooth build-up is presented.

Case Report: A Predictable Technique to Establish Occlusal Contact in Extensive Direct Composite Resin Restorations: The DSO-Technique

This paper describes the application technique of direct shaping by occlusion (DSO) for large composite restorations including the entire occlusal surface. For this technique, matrix bands and wedges are inserted without interference with antagonists in the desired occlusion. The final increment of soft-composite resin is shaped by letting the patient occlude on the uncured composite. Due to the nature of the technique, special care has to be taken for moisture control and handling of contamination. The procedure, advantages, and limitations of the technique are discussed.

Impact of lateral occlusion schemes: A systematic review

STATEMENT OF PROBLEM

Although several lateral occlusion philosophies have been proposed in the literature, there is a lack of compelling evidence supporting any scheme.

PURPOSE

The purpose of this systematic review was to investigate the clinical implications of different lateral occlusion schemes.

MATERIAL AND METHODS

A literature search was completed through PubMed (MEDLINE), Google Scholar, and Cochrane Library, up to January 2014. The literature search aimed to retrieve 2 study categories: group 1: comparative studies; group 2: clinical outcome studies. The inclusion criteria were peer-reviewed human clinical studies published in English. The search was further supplemented by manual searching through the reference lists of the selected studies.

RESULTS

The initial search revealed a total of 680 studies; however, after applying the inclusion criteria, 26 studies were found suitable for the analysis (13 for group 1 and 13 for group 2). The most commonly evaluated lateral occlusion schemes were canine-guided occlusion (CGO) and group function occlusion (GFO). Group 1 studies evaluated the impact of lateral occlusion schemes on muscular electromyographic (EMG) activity, condylar displacement, mastication, and mandibular movement. Group 2 studies evaluated the impact of restored occlusion on longevity, patient comfort, and pathologic consequences. CGO was associated with narrower mastication and less EMG activity of the masticatory muscles during clenching. GFO was associated with wider mandibular movement and quicker mastication. During mastication, there was no difference in EMG activity between the 2 lateral occlusion schemes. Furthermore, the long-term studies indicated that there is no difference between the 2 schemes in patient comfort and restoration longevity.

CONCLUSION

Although there are immediate differences between the different lateral occlusion schemes, patients have the capability to successfully adapt to CGO or GFO.

A Single Visit Direct Technique to Provisionally Restore Occlusion for a Full-Mouth Rehabilitation: A Clinical Report

Attrition of the dentition can negatively affect esthetics and function. When reconstructing patients with attrition who require restoration at increased occlusal vertical dimension (OVD), it is necessary to first evaluate the OVD using a removable interim prosthesis to ensure that the patient will tolerate the new position. The transition to fixed interim prostheses has to be carefully planned to achieve the desired OVD. One approach is to prepare all teeth in a single day and place full-arch interim prostheses; however, this can be tiring for the patient and prosthodontist. An alternative approach is to prepare one arch and place interim prostheses, while using composite resin in the opposing arch to maintain the newly established OVD. A diagnostic wax-up at the proposed OVD is completed and duplicated in stone. A vacuform matrix is loaded with composite resin and applied to the unprepared etched teeth of the opposing arch to restore form and occlusion until full contour interim prostheses are placed at a later visit.

Conservative Restoration of Worn Mandibular Anterior Teeth Combining Gingival Repositioning and a Template Matricing Technique

Conservative resin composite restoration of worn mandibular anterior teeth may offer an alternative option to full-coverage restorations for the patient. Assessment of the occlusal condition is critical because alterations in occlusal vertical dimension may not always be possible. By exposing additional coronal tooth structure, periodontal crown-lengthening procedures can serve to increase clinical crown height when adequate attached gingival tissue is present and supra-eruption has likely occurred. Fabrication of a custom template made from a diagnostic mock-up with proximal stainless steel matrices helps contribute to a predictable restorative result and improves chairside efficiency for the dental practice. By combining gingival crown lengthening, bonding of resin composite material, and selective occlusal adjustment; a short to medium-term, conservative option can be made available for the patient.

Impact of erosive conditions on tooth-colored restorative materials

OBJECTIVES

To give an overview of the impact of erosive conditions on the behavior of tooth-colored restoratives and performance of dental adhesives.

METHODS

Acid-induced erosive lesions of enamel and dentin often need restorative procedures for rehabilitation. Nowadays, mostly tooth-colored restoratives (ceramics or resin composites), which are adhesively fixed to the dental substrate are used for this purpose. In some cases it might be necessary to seal the exposed dentin before achieving this goal in order to combat hypersensitivities and to protect those teeth from further erosive and abrasive loss. Moreover, it is conceivable that patients will fall back into their old "erosive behavior" after the application of restoratives. The following overview describes in how far intra-oral erosive conditions might affect the integrity of restorative materials, such as composite resins and ceramics, or of dentin sealants. Additionally, the use of erosively altered enamel and dentin as substrate for adhesive technologies is elucidated.

RESULTS

In the literature, information of the behavior of tooth-colored restoratives under still persisting erosive conditions are limited and mostly based on in vitro-studies. There is information that the adhesion of dental adhesives to eroded dentin is compromised as compared to regular dentin. The impact of erosive conditions relevant for the oral cavity on ceramics and resin composites seems to be rather low, although only few clinical studies are available.

SIGNIFICANCE

The review showed that erosive conditions might have only little impact on behavior of tooth-colored restorative materials, such as composites and ceramics. Dentin sealants also seem to be rather resistant against erosive conditions and might therefore serve as an intermediary treatment option for exposed dentin surfaces. The adhesion of dentin adhesives to eroded dentin might be increased by mechanical pre-treatment of the substrate, but needs further investigation.

Marginal adaptation of direct class II composite restorations with different cavity liners

The aim of this study was to evaluate how cavity linings with different elastic modulus can influence the marginal adaptation (MA) of Class II composite restorations before and after thermo-mechanical loading.

MATERIALS AND METHODS

Forty Class II cavities with margins extending 1 mm below the cement-enamel junction were prepared in extracted human third molars. In each group except the control group, a lining material of 1-mm thickness was applied to the bottom of the cavity and polymerized before placing the resin composite Herculite XRV Ultra (group A: control; group B: Premise Flowable lining; group C: Herculite XRV Ultra lining; and group D: Optibond FL lining). MA was evaluated (with a scanning electron microscope) before and after loading (200,000 loading cycles). Statistical analysis was done using the Shapiro-Wilks test, the analysis of variance test, and Duncan post hoc test at p<0.05.

RESULTS

Before loading, the percentages of continuous margins in dentin were superior (p<0.05) for groups C and D (71.1% and 87.2%, respectively) compared to groups A and B (55.7% and 48.3%, respectively). After loading, group D (79.8%) was statistically superior in dentin compared to all of the other groups (43.6%, 35.9%, and 54.4%, respectively). In occlusal enamel, no significant difference was found between groups. The percentage of enamel fractures and the percentage of noncontinuous margins in proximal enamel were high, with no significant difference between liners. It can be concluded that for the materials used in this study, a 1-mm-thick lining with an extremely low elastic modulus (2-3 GPa) could redistribute shrinkage stress. The use of a flowable composite did not significantly improve MA.

Implementation and experience of a new method for posterior vertical bite reconstruction using direct resin composite restorations in the private practice--a survey

OBJECTIVE

The purpose of the present survey was to evaluate the implementation and experience of a new method for posterior vertical bite reconstruction using direct resin composite restorations by private practitioners who attended a hands-on continuing education course on this technique.

MATERIALS AND METHODS

In the years 2007 and 2008, 17 1-day continuing education courses on vertical bite reconstruction in the worn dentition by using direct resin composite restorations were attended by 310 participants. A 13-item questionnaire was posted to all course participants in April 2009 seeking information on the acceptance, implementation and experience of the presented technique in the private practice.

RESULTS

A total of 97 (31%) questionnaires were returned, whereas 67% of the respondents had used the presented technique. Analysis of the overall experience and satisfaction with the placed resin composite restorations using visual analog scale (VAS) revealed a mean VAS score of 7.2 ± 1.7 (0 = maximal unsatisfied, 10 = maximal satisfied). The direct resin composite restorations were predominantly rated 'good' within the assessed criteria surface texture, anatomical form, marginal integrity, marginal discoloration and color match. Ninety-eight percent of the private practitioners stated that they would continue to carry out vertical bite reconstructions according to this technique. The three most frequently observed clinical problems were related to marginal discolorations, bulk fractures and adhesive failures.

CONCLUSION

The presented restoration method was well accepted by private practitioners who used this treatment approach at least once after course participation, even though some clinical problems were observed.

Current concepts on the management of tooth wear: part 2. Active restorative care 1: the management of localised tooth wear

This second of the four part series of articles on the current concepts of tooth wear management will focus on the provision of active restorative care, where the implementation of a preventative, passive approach may prove insufficient to meet the patient's expectations, or indeed prove to be sufficiently adequate to address the extent of the underlying pathology to the desired level of clinical satisfaction. The active restorative management of cases presenting with localised tooth wear (of either the anterior, posterior, maxillary or mandibular variety) will be considered in depth in this paper, including a description of the commonly applied techniques and treatment strategies, where possible illustrated by case examples.

Aesthetic resin onlay restorations: 'rationale and methods'

Resin composite restorations have gained increasing popularity over the past two decades. This has been largely driven by a patient-orientated demand for the use of aesthetic restorative materials. It has occurred concomitantly with an improvement in the mechanical properties of available materials, and advances in our knowledge of resin bonding. Onlay restorations are advocated for a plethora of clinical applications. This paper considers the role of adhesive onlay restorations fabricated in resin composite in contemporary restorative practice, including the presentation of two case reports.

CLINICAL RELEVANCE

This case report describes a minimally invasive, aesthetic solution to provide cuspal coverage by means of either a direct or indirect resin composite onlay restoration, respectively.

Composite vertical bite reconstructions in eroded dentitions after 5·5 years: a case series

In the following case series, we report on six cases of erosive worn dentitions (75 posterior teeth), which have been reconstructed using a template-based technique with direct composite resin restorations and already examined after 3 years in service. In all patients either one or both tooth arches were completely restored using direct resin composite restorations. A wax-up-based template was used to avoid freehand build-up techniques and to ensure optimal anatomy and function. All patients were re-assessed after a mean service time of 5·5 years (mean 67 ± 4 months) using United States Public Health Service criteria. The overall quality of the restorations was good with predominantly 'alpha' and 'bravo' scores, respectively. However, the restorations showed some deterioration with respect to marginal quality, marginal discoloration, surface texture and anatomy as compared to the 3-year investigation. The marginal impairments could be resolved by polishing. It is concluded that this non-invasive technique provides a possible treatment option at least for the displayed observation period of 5·5 years.

[Paradigm shift in conservative dentistry: from a mechanistic to a prevention-oriented perception]

The application of different preventive measures has resulted in a decline of clinically detectable carious lesions in children and adolescents. Not only have caries symptoms changed significantly, but the number of extracted teeth in adults has decreased. Due to these epidemiological facts, modern conservative dentistry is based on a careful risk analysis and caries diagnosis, which also takes into consideration biological and psychosocial components of caries etiology. Conservative dentistry will fail if the dentists are only interested in repairing defects. Simultaneous with the positive outcome of prevention, some unanswered problems have arisen, for which there are no adequate solutions. In young children, caries prevalence is still high and the restorative care of these primary teeth should be improved. For adolescents, early detection of carious lesions should be improved and polarization of caries prevalence should be eliminated. In older adults, evidence-based therapy options for treatment of erosions, abrasions, and root caries are lacking. For seniors needing general care, preventive and restorative concepts should be established.

Multiple bonded restorations in a patient with severe mental disability: a case report

Dental treatment for patients with special needs may require general anesthesia, if these patients are unable or unwilling to cooperate. To administer a restorative treatment in a limited timeframe requires an interdisciplinary approach adapted to the individual. This case report describes a comprehensive restorative procedure in a patient with severe mental disability who has serious dental caries. Direct resin composites were used to reconstruct most of the damaged dentition. In the 22-month follow-up conducted by the authors, they found one restoration failure, several primary caries lesions and one secondary-caries lesion. Every other restoration remained stable, despite limited postoperative care.

Dental Erosion

There is some evidence that dental erosion is steadily spreading. To diagnose erosion, dental professionals have to rely on clinical appearance, as there is no device available to detect it. Adequate preventive measures can only be initiated if the different risk factors and potential interactions between them are known. When substance loss, caused by erosive tooth wear, reaches a certain degree, oral rehabilitation becomes necessary. Prior to the most recent decade, the severely eroded dentition could only be rehabilitated by the provision of extensive crown and bridgework or removable dentures. As a result of the improvements in composite restorative materials and in adhesive techniques, it has become possible to rehabilitate eroded dentitions in a less invasive manner.