Tooth Wear Research Articles

Resistance of CAD/CAM composite resin and ceramic occlusal veneers to fatigue and fracture in worn posterior teeth: A systematic review.

Severe tooth wear is related to substantial loss of tooth structure, with dentin exposure and significant loss (≥1/3) of the clinical crown. The objective of this systematic review was to summarize and analyze the scientific evidence regarding the mechanical performance of computer-aided design/computer-aided manufacturing (CAD/CAM) composite resin and CAD/CAM lithium disilicate ceramic occlusal veneers, in terms of fatigue and fracture resistance, on severely worn posterior teeth. Currently, occlusal veneers are an alternative for treating worn posterior teeth. Although scientific evidence demonstrates the good performance of lithium disilicate occlusal veneers, there are less brittle materials with a modulus of elasticity more similar to dentin than ceramics, such as resin CAD/CAM blocks. Therefore, it is important to identify which type of material is best for restoring teeth with occlusal wear defects and which material can provide better clinical performance. This review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A comprehensive search of the PubMed, Embase, Web of Science, Scopus, Cochrane, OpenGrey, Redalyc, DSpace, and Grey Literature Report databases was conducted and supplemented by a manual search, with no time or language limitations, until January 2022. We aimed to identify studies evaluating the fatigue and fracture resistance of CAD/CAM composite resin and ceramic occlusal veneers. The quality of the full-text articles was evaluated according to the modified Consolidated Standards of Reporting Trials (CONSORT) criteria for in vitro studies, and 400 articles were initially identified. After removing duplicates and applying the selection criteria, 6 studies were included in the review. The results demonstrated that the mechanical performance of CAD/CAM composite resin occlusal veneers is comparable to that of CAD/CAM lithium disilicate occlusal veneers in terms of fatigue and fracture resistance.

Domain adaptation neural network based prediction of real-time drill bit tooth wear

Drill bit wear reduces drilling efficiency and escalates operational risks. The drill bit tooth wear grading is a measure of lost tooth height. Accurate monitoring of drill bit tooth wear grade is crucial to adjust drilling parameters and plan timely bit replacement, significantly enhancing drilling efficiency and safety. Current real-time monitoring methods for drill bit wear exhibit limitations, particularly in accounting for variations in the geological formation and drilling parameters, resulting in poor model stability. This paper proposes an intelligent modeling approach that utilizes a Domain Adaptation Neural Network (DANN) to establish an ideal drilling rate of penetration (ROP) prediction model. By incorporating measured ROP, wear coefficients are calculated, and a relationship between wear coefficient and tooth wear grade is established, facilitating real-time monitoring of drill bit tooth wear grade. Test results on ten drill bits demonstrate that the DANN ideal ROP prediction model, leveraging data from new drill bits, enhances the model's adaptability to varying working conditions for new drill bits, thereby improving the accuracy of ideal ROP predictions. We establish relationship between calculated wear coefficients and tooth wear grades. The results indicate that the average error in inner wear grade is 0.6 (7.5%) and the average error in outer wear grade is 1.3 (16%) on an 8-point scale which demonstrates the model's effectiveness in monitoring drill bit tooth wear.

Fluoride concentration and pH in bottled waters commercialized in Chile: Implications for oral health

An increased consumption of bottled water is overshadowing the traditional intake of tap water. Community water fluoridation is described an effective public measure for delivering fluoride (F) for dental caries prevention. Although community water fluoridation implementation varies regionally, it is desirable that our daily water contains optimal fluoride levels and a safe pH for dental health protection. Here, we determined F concentration and pH of commercially available bottled waters in Chile. Varieties (mineral, purified, and flavored) were obtained in duplicate from different batches. F and pH were measured using a calibrated F-specific ion electrode and pH meter, respectively. From 76 different brands, 100 % have F concentrations below the recommended range (0.6–1.0 ppm F), mineral water showing significantly higher levels (0.15±0.009; p<0.05) than purified (0.09±0.080), and flavored (0.07±0.063). Most brands exhibited levels below the critical pH for both enamel (71.05 %, n=54) and dentine (80.26 %, n=61). A 46.1 % (n=35) had values below pH 4. Flavored waters had significantly lower pH (3.19±0.12; p<0.05), than purified (6.16±2.81) and mineral (pH 6.21±2.59). The analyzed bottled water, regardless of type, lack sufficient F for caries prevention. Their low pH, particularly in flavored options, might be related to an increased risk of erosive tooth wear. Implementing fluoride and pH labeling is desirable to empower consumers to make informed decisions.

Dental Erosive Wear Assessment amongst Different Age Groups Utilising Basic Erosive Wear Examination: An Epidemiological Study

Introduction: The study aims to assess the prevalence of erosive tooth wear and risk levels amongst different age groups utilising Basic Erosive Wear Examination (BEWE) amongst the population of South West Coastal India. Materials and Methods: One hundred and sixty healthy people participated in the research (n = 32 per group). Using sextants and the BEWE, index (0–18) allowed for the evaluation of erosive tooth wear. Questionnaires supplemented clinical data. Each participant was assigned to groups based on the severity of their erosive wear: high (BEWE sum ≥ 14), moderate (BEWE sum 9–13), low (3–8) and none (0–2). Results: There is no significant difference in the degree of erosive tooth wear across different age groups (χ2– 20.11, P – 0.067 [not-significant]). There is a significant difference in response to questions across different age groups (χ2 – 487.21, P – 0.01 [significant]). Conclusion: The prevalence of erosive tooth wear grows as individuals age. Older age groups, patients who are at a higher risk level require a more comprehensive form of treatment. The aetiology of dental erosion remained unknown to the patients, indicating a deficiency in their understanding of erosive tooth wear.

Increasing Vertical Dimension of a Case with Full Mouth Rehabilitation: Case Report.

Introduction: Bruxism is one of the most frequent causes for occlusal tooth wear, with the loss of tooth structure caused by mechanical wear between maxillary and mandibular tooth surfaces, case report was conducted to improve the patient oral health, and to maintain the new vertical dimension since it was lost by teeth clenching. Case description: this paper presents a 50 years old male suffering from severe bruxism, which implicated the appearance and function of the patient, he was transferred to TIU dental hospital for full mouth rehabilitation treatment. Discussion: The rehabilitation of patients with extensive occlusal wear is complex and difficult to solve, becoming thus one of the biggest challenges of dentistry, a proper planning of a prosthetic rehabilitation should not attribute the re-establishing of occlusal vertical dimension (OVD) to new prostheses at the risk of the patient doesn’t adapt to a new condition of vertical dimension. Conclusion: Tooth wear causes dimensional changes in facial morphology and OVD decrease. The correct determination of occlusal vertical dimension represents a factor of success in the rehabilitation treatment. Keywords: Vertical Dimension, Rehabilitation, Full Mouth, Bruxism.

Protecting primary teeth from dental erosion through bioactive glass

ObjectivesThe present study aimed to evaluate the effectiveness of bioactive glass (BAG) in preventing dental erosion in primary teeth. MethodsEnamel and dentin specimens (2 × 2 × 2 mm) were obtained from extracted primary teeth, which were randomly divided into the following groups based on the pretreatments (n = 12): DW (deionized water), NaF (2 % sodium fluoride), 2BAG (2 % BAG), 4BAG (4 % BAG), 6BAG (6 % BAG), and 8BAG (8 % BAG). The specimens were immersed in the respective solutions for 2 min and subjected to in vitro erosive challenges (4 × 5 min/d) for 5 d. The erosive enamel loss (EEL), erosive dentin loss (EDL), and the thickness of the demineralized organic matrix (DOM) were measured using a contact profilometer. The surface microhardness (SMH) was measured, and the percentage of SMH loss (%SMHL) was calculated. The surface morphology and mineral composition were evaluated by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS), respectively. ResultsAfter the erosive challenges, the EEL, EDL, and%SMHL of the 2BAG, 4BAG, 6BAG, and 8BAG groups significantly reduced, with the greatest reduction was observed in the 6BAG (EEL: 6.5 ± 0.2 μm;%SMHL in enamel: 12.8 ± 2.6; EDL: 7.9 ± 0.3 μm; %SMHL in dentin: 22.1 ± 2.7) and 8BAG groups (EEL: 6.4 ± 0.4 μm;%SMHL in enamel: 11.0 ± 1.9; EDL: 7.8 ± 0.5 μm; %SMHL in dentin: 22.0 ± 2.5) (P < 0.05). With increasing BAG concentrations, the number of surface deposits containing Ca, P, and Si increased. Conclusions6BAG was the most effective for preventing dental erosion in primary teeth and showed a particularly strong potential for dentin erosion prevention. Clinical SignificanceBioactive glass, especially at a 6 % concentration, has proven effective in reducing erosive tooth wear and surface microhardness loss while also protecting demineralized organic matrix in primary dentin.

Ecology of large ungulates in the northeastern Iberian Peninsula during the Upper Palaeolithic through stable isotopes and tooth wear analysis

The northeastern Iberian Peninsula acted as a refuge zone during the Late Pleistocene where the persistence of terrestrial ecosystems could provide hunter-gatherers with large prey, mainly horse (Equus ferus) and red deer (Cervus elaphus). Isotopic (δ13C, δ18O, δ15N) and dental wear (mesowear and microwear) analyses have been applied on the remains of both species from the archaeological sites of Arbreda and Bora Gran at Serinyà (Girona), where evidence of human occupation from the Mousterian to the Magdalenian has been attested. The incremental enamel analysis on horse teeth revealed seasonal variation in carbonate δ18O but no detectable change in carbonate δ13C values, reflecting a rather stable diet and habitat over the year. Nevertheless, higher inter-individual than intra-individual contrast in carbonate δ13C indicate different environmental conditions from one individual to another for each stratigraphic unit. In red deer teeth, seasonal signals in enamel carbonate δ13C and δ18O demonstrated mirrored trends. Further, red deer show higher δ13C values than those of horses, both in enamel carbonate and bone collagen, as well as higher variability in mesowear and microwear scores, reflecting a mixed-feeding habit. Despite a strong grazing signal in mesowear and microwear, the lower δ13C values for horses suggest a higher dependence on relatively more humid habitats than red deer, which likely foraged in dryer environments with xeric plants during winter. These differences in ecological partitioning are particularly well illustrated in distinct collagen δ13C and δ15N values during the harsh climatic conditions of the Final Gravettian coeval to the GS-3 or Last Glacial Maximum. The capacity of red deer to adapt to fluctuating environmental conditions contrasts with the niche persistence of horse allowed by the availability of mosaic habitat.

Patient preventive advice to mitigate signs and symptoms of tooth wear

Tooth wear has profound consequences for a patient's oral health and quality of life. Education on preventive advice has been suggested as a method of reducing the burden of tooth wear in the population. This review provides an update on preventive advice regarding the mitigation of tooth wear, and presents evidence-based clinical recommendations that dental professionals can use chairside. CPD/Clinical Relevance: Preventive advice for tooth wear patients may help prevent tooth wear and its progression.

Restoring a smile: full-mouth rehabilitation of an elderly patient

Tooth wear is a significant problem in the ageing population and has increased in prevalence over the last century owing to the increase in life expectancy. Further, with the advances in dentistry, people tend to retain more of their natural dentition until the seventh or eighth decade of their lives and leading to an increased number of people with tooth wear. A certain degree of physiological tooth wear is inevitable over a lifetime as a result of the continuous function of the dentition. CPD/Clinical Relevance: A removable prosthesis, used in patients with severely worn teeth, is cost-effective compared to other prosthetic options and can be easily maintained hygienically.

Hard drugs use and tooth wear: a scoping review.

This study aims to map evidence on the relationship between hard drug use and dental wear. The scoping review is guided by the question: What is the relationship between hard drug consumption and dental wear? Adhering to PRISMA-ScR guidelines, searches were conducted across PubMed, Embase, and four databases in March 2024. Inclusion criteria included studies investigating the association between hard drug use and dental wear, regardless of publication date or language. Data were presented through narrative exposition, tables, and a conceptual framework. Twenty-eight studies (four case-control, three cross-sectional, five case reports, and sixteen literature reviews) were included. Among case-control studies, 75% observed an association between drug use and dental erosion; however, no cross-sectional studies demonstrated this association. Despite questionable quality, reviews established connections between drug use and dental erosion. Studies aimed to elucidate potential causes for dental erosion. Analysis suggests a potential link between hard drug use and dental wear, though indirect. Factors like bruxism and reduced salivary pH may contribute to dental wear among drug users. Further investigation through primary studies exploring this relationship is necessary. Dentists should focus not only on clinical characteristics of dental wear but also on mediating factors such as bruxism and decreased salivary pH associated with drug use. This holistic approach allows for a deeper understanding of dental wear mechanisms, enabling targeted preventive and therapeutic interventions.

Method for a Comprehensive Analytical Study of Contact Pressures, Wear, and Durability of Metal-Polymer Helical and Spur Gears with Steel Pinion and Polyamide Gear

An analytical complex study of metal-polymer (MP) helical and spur gears by a new author's analytical method was carried out. The influence of the helix angle on the contact pressures in the engagement, the teeth wear, and the durability of the MP gears of different polymers has been established. MP gears with a pinion made of carbon steel (0.45% C) and gear made of basic polyamides PA6, PA66, and their composites with the following fillers: fiberglass (PA6+30GF), carbon fiber (PA6+30CF), molybdenum disulfide (PA6+MoS2), and oil filled cast polyamide (PA6+Oil) are studied. According to the developed procedure for determination of the angles of engagement parity change, it is shown that there is two-one-two-pair or three-two-three-pair engagement depending on the helix angle. Quantitative and qualitative regularities of changes in the initial maximum contact pressures and their reduction due to tooth wear over the time from the moment of the entrance of teeth to engagement up to their exit from it are established. In particular, at a helix angle of β = 10°, the contact pressures reduce to 33% compared to spur gears. The linear wear of the gear polymer tooth profile at selected points of engagement and different helix angles has been investigated, and the influence of the pressure angle on it is shown. It is established that its regularities of change during the engagement phase are the same for all polymeric materials studied. The durability of transmissions is calculated, and its comparative evaluation is given. At the helix angle β = 5°, a slight increase in durability is achieved compared to spur gears, and at β = 10° the durability of MP gears increases by about 1.5 times for all polymeric materials studied.

Prey size reflected in tooth wear: a comparison of two wolf populations from Sweden and Alaska.

Ingesta leaves distinct patterns on mammalian teeth during mastication. However, an unresolved challenge is how to include intraspecific variability into dietary reconstruction and the biomechanical aspects of chewing. Two extant populations of the grey wolf (Canis lupus), one from Alaska and one from Sweden, were analysed with consideration to intraspecific dietary variability related to prey size depending on geographical origin, sex and individual age as well as tooth function. Occlusal enamel facets of the upper fourth premolars, first molars and the second lower molar were analysed via three-dimensional surface texture analysis. The Swedish wolves displayed facets characterized by higher peaks and deeper, more voluminous dales, featuring an overall rougher surface than the wolves from Alaska. Compared to females, the Swedish male wolves had a slightly larger dale area and hill volume on their facets. Upper fourth premolars are smoother and had higher values in texture direction compared to upper first molars. The upper first molars were rougher than the occluding lower second molars and were characterized by larger and deeper dales. We find evidence supporting intraspecific dietary segregation, and antagonistic asymmetry in occlusal wear signatures. The data offer new insights into the roles of apex predators like the grey wolf.

Gingival health, plaque accumulation, and restoration outcomes in deciduous anterior teeth: evaluating zirconia crowns versus composite resin strip crowns.

Zirconia crowns, resembling crystals and with enamel-like aesthetics, are recent entrants in pediatric restorative dentistry. Despite growing use, their empirical efficacy remains under-explored. The aim of this study is to compare resin composite strip crowns and premanufactured zirconia crowns on primary maxillary incisors. In the Pediatric Dental Clinics, 240 primary maxillary incisors (69 patients) were treated with either zirconia (120 teeth) or composite strip crowns (120 teeth). Evaluations of gingival health, plaque, secondary caries, restoration failure, and opposing teeth wear occurred at 3, 6, and 12-month intervals. At 3 months, zirconia crowns showed less gum bleeding (P=0.006) and plaque. Through 6 and 12 months, zirconia crowns exhibited fewer failures but higher opposing teeth wear. Strip crowns indicated greater tooth material loss. Zirconia crowns demonstrated superior gingival health and durability over composite resin strip crowns but caused increased wear on opposing teeth.

Intraoral scanner-based monitoring of tooth wear in young adults: 36-month results

ObjectivesThe study continues our longitudinal observation of wear aiming to further monitoring of progression and lesion morphology and to identify relationships with assumed aetiological factors.Materials and methodsMolars (FDI #36 or #46) of 74 participants (23.8 ± 2.2 years) were scanned (Trios 3, 3Shape) at the third follow-up (T3; observation period 1,111 ± 10 days). Data sets from T3, T2 (24-month follow-up) and T1 (12-month follow-up) were superimposed with baseline in a 3D analysis software (GOM Inspect). Wear was quantified as maximum vertical tissue loss (µm; median, 95% CI) in various occlusal areas (4/5 cusps and 2 ridges). Morphologies were classified into cupping (C), facet (F), and combined cupping-facet (CF). Aetiological factors were assessed with questionnaires.ResultsWear increased at T3 significantly at low rates in all areas of the occlusal surface (median between 7.0 (4.0;10.5) and 9.5 (6.0;15.0) µm). There was a clear trend for higher loss values in males, but no association with other factors such as nutrition. C and CF showed significantly higher loss values than F. Areas without initial wear developed F first, which either persisted or developed into C and CF.ConclusionsWear continued at low rates with C/CF morphology and sex as significant factors. Cupped lesions seem to develop from facets and thus may not be a valid diagnostic criterion for erosive tooth wear.Clinical relevanceWear is a cumulative process that apparently follows complex mechanisms that cannot be conceptualized in simplified terms; C and CF may be indicators for higher progression rates.

Evidence-based clinical management of localised tooth wear and a repeatedly dislodged posterior crown utilising the Dahl Concept.

This clinical case report demonstrates the use of the Dahl Concept in the management of the repeated dislodgement of a posterior full coverage crown associated with a reduced restorative space. The described technique harnesses the addition of resin composite and a temporarily cemented provisional full coverage crown to create sufficient restorative space for the cementation of a definitive posterior full coverage crown restoration at the six-month review.

Case of precise full-mouth occlusal reconstruction guided by digital occlusal function analysis.

The clinical demand for occlusal reconstruction increases rapidly with increasing number of patients who have lost their normal occlusion because of tooth wear and dentition defects. Occlusal reconstruction is a special type of restoration defined as a comprehensive restoration of the function of the stomatognathic system by reestablishing a uniform and stable occlusal relationship between the upper and lower dentitions. Occlusal function analysis is an important part of occlusal reconstruction to achieve accurate restoration design and adjustment. Digital occlusal function analysis was conducted to monitor the movement of the mandible and obtain related data for the parameter design of occlusal reconstruction. Preoperative design, intraoperative adjustment, and postoperative verification were achieved, thereby improving the efficiency and accuracy of occlusal reconstruction.

Risk analysis Erosive Tooth Wear (ETW): checklist for a quick assessment of the risk factors for ETW in the dental practice

Erosive Tooth Wear (ETW) is the loss of tooth structure without bacterial involvement. As the resulting loss of tooth structure is irreversible, an early evaluation of the multifactorial etiology, accurate diagnosis and regular follow-up are essential. The ETW is dynamic and its progression should be continuously monitored. A risk analysis table was developed to systematically record risk factors for ETW (Fig. 2). This allows ETW management to be integrated more efficiently into clinical practice and the progression to be documented over the years. If ETW is assumed, the risk analysis should be performed and updated at least every two years. In the assessment, risk-promoting and risk-inhibiting factors are marked, added together and compared. If the negative factors pre-dominate, measures should be taken to minimize the risk for ETW. The main purpose of the risk analysis is therefore to evaluate the individual etiology, coun-teract negative factors, promote positive factors and prevent progression.

Association between oral health and cognitive impairment in older adults: Insights from a Six-year prospective cohort study

ObjectiveThis study aims to investigate the relationships between four baseline oral conditions (periodontal status, dental caries, tooth wear, and dentition) and repeated global cognition or domain-specific cognition (memory, executive function, attention, and verbal fluency) in non-demented older adults over time. MethodsThis prospective cohort study (2011–2019) enrolled 516 non-demented community-dwelling older adults (age ≥ 65) to explore the association between oral health and cognitive function. Global and domain-specific cognition were assessed biennially (four repeats) using a battery of neuropsychological tests. The baseline oral health conditions were examined, including periodontal status, dental caries, tooth wear, and dentition. The association of these oral conditions with cognition was evaluated by generalized linear mixed models. Stratified analyses were performed by important covariates. ResultsOver time, dental caries was associated with poor memory in two different logical memory tests (β^= -0.06 and β^= -0.04). Incomplete dentition with less than 28 teeth was associated with poor performance in attention (β^= -0.05) and verbal fluency (β^= -0.03). These associations became more evident in those with an elevated inflammatory marker (IL-6, β^= -0.11 to -0.08). In contrast, tooth wear was associated with better memory in two different logical memory tests (β^= 0.33 and β^= 0.36) and better executive function (β^= 0.06) over time, and this association became more evident in those with the lowest inflammatory marker (IL-6, β^= 0.10). ConclusionsDental caries and incomplete dentition were associated with poor memory, attention, and verbal fluency performance. Conversely, tooth wear was associated with better memory performance and executive function. Clinical SignificanceFor early prevention of dementia, an evaluation of multiple dental and periodontal status in older adults helps predict the risk of dementia in the preclinical phase. Maintaining intact tooth structure without caries progression and eventually tooth loss may help prevent the worsening of memory, attention, and verbal fluency over time.

Interaction of Statherin-Derived Peptide with the Surface of Hydroxyapatite: Perspectives Based on Molecular Dynamics Simulations

Introduction: Statherin-derived peptide (StatpSpS) has shown promise against erosive tooth wear. To elucidate its interaction with the hydroxyapatite (HAP) surface, the mechanism related to adsorption of this peptide with HAP was investigated through nanosecond-long all-atom molecular dynamics simulations. Methods: StatpSpS was positioned parallel to the HAP surface in 2 orientations: 1 – neutral and negative residues facing the surface and 2 – positive residues facing the surface. A system containing StatpSpS without HAP was also simulated as control. In the case of systems with HAP, both partially restrained surface and unrestrained surface were constructed. Structural analysis, interaction pattern, and binding-free energy were calculated. Results: In the peptide system without the HAP, there were some conformational changes during the simulation. In the presence of the surface, only moderate changes were observed. Many residues exhibited short and stable distances to the surface, indicating strong interaction. Specially, the residues ASP1 and SER2 have an important role to anchor the peptide to the surface, with positively charged residues, mainly arginine, playing a major role in the further stabilization of the peptide in an extended conformation, with close contacts to the HAP surface. Conclusion: The interaction between StatpSpS and HAP is strong, and the negative charged residues are important to the anchoring of the peptide in the surface, but after the initial placement the peptide rearranges itself to maximize the interactions between positive charged residues.

Intraoral wear of PICN CAD-CAM composite restorations used in severe tooth wear treatment: 5-year results of a prospective clinical study using 3D profilometry

ObjectivesTo evaluate, in a prospective clinical study over 5 years with ex vivo 3D profilometry analyses, the intraoral wear of Polymer-Infiltrated Ceramic Network (PICN) CAD-CAM composite restorations used in severe tooth wear treatment with the One-Step No-Prep technique. Methods192 PICN (Vita Enamic) restorations on molars and premolars were included in a prospective clinical study involving patients treated according to the One-step No-prep protocol (n = 7). All patients showed clinical signs of bruxism. Replicas of restorations on molars and premolars were realized at each evaluation time (baseline and then every year up to 5 years) and scanned to perform 3D profilometry. Baseline and recall scans were superimposed with Geomagic Control software. The mean material wear was calculated for the full occlusal area (FOA) and for the occlusal contact area (OCA), respectively. Clinical evaluation of restorations was performed at recall. ResultsAt 5 years, the estimated mean material wear for FOA was inferior to the accuracy threshold of the profilometry measurement chain. For OCA, the estimated mean wear of the material was – 27.97 µm. This material wear was shown to be significantly influenced by time (p < 0.0001) and patient (p = 0.026), while the type of tooth (molar or premolar) had no influence. At 5 years, the survival and the success rates of restorations were 99.48% and 90.62%, respectively. SignificanceThe PICN material exhibits a low wear process in the treatment of severe tooth wear despite the presence of clinical signs of bruxism, and it constitutes a suitable material for the One-step No-prep technique.