Minimal Tooth Preparation Research Articles

Rehabilitation of Anterior Esthetics Using CAD-CAM Fabricated Zirconia Maryland Bridge: A Case Report.

Introduction: Missing anterior teeth have a great impact on the psychological status of an individual due to the unesthetic appearance. These can be restored using removable prostheses, conventional bridges, resin-bonded prostheses, or implants. A resin-bonded fixed prosthesis is a minimally invasive treatment option in such cases to restore function and esthetics. Case Presentation: This case report describes the CAD-CAM zirconia Maryland bridge as a treatment modality for effective restoration of the missing maxillary central incisor in a 32-year-old female patient who reported the chief complaint of unesthetic appearance. The patient had a history of extraction due to trauma 6 months ago with normal overjet and overbite. Discussion: One of the types of resin-bonded prosthesis is a Maryland bridge which involves minimal tooth preparation with supragingival margins, thus maintaining periodontal health. Maryland bridges enhance dental esthetics with minimal loss of tooth structure. Conclusion: CAD-CAM fabricated all-ceramic resin-bonded prosthesis is an efficacious way of replacing missing anterior teeth, restoring function, providing excellent esthetics, and thus boosting patient’s confidence. Keywords: CAD-CAM zirconia, Maryland bridge, missing anterior tooth, resin-bonded fixed prosthesis, resin-bonded restoration.

Transitioning from injectable resin composite restorations to resin composite CAD/CAM veneers: A clinical report.

To describe a shift from injectable resin composite technique to composite resin computer-aided design and computer-aided manufacturing (CAD/CAM) veneers in addressing esthetic concerns associated with diastemas between anterior lower teeth in a clinical case. Among several techniques proposed for direct resin composite restoration, the "Injectable resin composite technique" has gained popularity for its time-efficiency, reduced technique sensitivity, and diminished reliance on clinician skills. However, challenges such as staining and the need for frequent polishing follow-ups may prompt the consideration of more stable alternatives such as indirect veneer restorations. While ceramic veneers offer superior mechanical and optical properties, resin ceramic veneers, especially those milled from CAD/CAM resin ceramic blocks, offer advantages such as rapid, cost-effective production, simplified intra-oral repairs, less susceptibility to fracture, superior stress absorption, and requires minimal tooth preparation, making them an appealing option for many patients. Moreover, a fully-digital approach not only streamlines the process but also saves time and labor while ensuring the delivery of high-quality restorations to patients. In addressing a patient's dissatisfaction with constant polishing of direct resin composite restorations, a shift to resin composite CAD/CAM veneers was implemented. Utilizing a fully-digital approach with CAD/CAM resin ceramic restorations successfully restored both esthetics and function. While the injectable resin composite technique achieves immediate esthetic results, its low color stability necessitates frequent polishing sessions. The replacement of direct resin composite restorations with CAD/CAM resin composite veneers becomes a viable option for patients seeking more stable restorations that require fewer follow-ups. This transition addresses both esthetic concerns and the need for enduring solutions in restorative dentistry.

Exploring the Variability in Antibacterial Testing of Resin Dental Composites among Investigators: A Narrative Review

Caries is a common dental problem brought on by factors like excessive sugar consumption, poor oral hygiene, and the presence of microorganisms in the mouth. This dental pathology is treated with a variety of filling materials, including tooth-colored direct resin dental composite (RDC), glass ionomer cement (GIC), and dental amalgam (also known as silver filling). RDC is the most preferred filling material in dental clinics due to its excellent esthetics and minimal tooth preparation, making it the need of the modern era. However, antimicrobial agents were added to this material in order to enhance its ability to prevent secondary caries. The antibacterial activity of RDC has been tested using a variety of methods, but testing protocols have been found to vary. Thusly, the point of this article is to examine the disparity in the strategy involved by specialists for testing the antibacterial properties of RDCs.

Ultrathin Partial Ceramic Veneers in the Esthetic Zone with Tooth Whitening: A 5-year Case Report.

This case report describes a minimally invasive approach with tooth whitening and partial ceramic veneers in the esthetic zone with a 5-year follow-up. The patient was initially concerned about the tooth color and previous direct resin composite restorations that chipped on the incisal edges of both maxillary central incisors. Tooth whitening and partial veneers for both central incisors were recommended after clinical evaluation. Two sessions of in-office tooth whitening, first with 35% hydrogen peroxide and later with 10% carbamide peroxide from first premolar to first premolar, were provided. Minimal tooth preparation that only removed the fractured composite restorations was performed followed by placement of feldspathic porcelain ultrathin partial ceramic veneers for both central incisors. We emphasize the benefits of minimal tooth preparation paired with partial ceramic veneers and the importance of masking discolored tooth structure with such thin veneers, including potential tooth whitening. Overall, we demonstrate a well-planned and executed restorative procedure combining tooth whitening and ultrathin partial ceramic veneers to achieve desired results in the esthetic zone that remained successful for five years.

Research Progress and Clinical Application of All-Ceramic Micro-Veneer.

Anterior teeth problems affect the patient's daily eating, communication, social activities, self-confidence, and mental health. The trend in dentistry is to address anterior tooth problems with minimally invasive and aesthetic treatments. With the development of adhesive materials and ceramics, micro-veneers have been proposed as an alternative treatment for enhancing the aesthetic appearance and avoiding unnecessary tooth reduction. A micro-veneer is a veneer that can be cemented to the surface without or with minimal tooth preparation. These benefits include no need for anesthesia, postoperative insensitivity, good adhesion to enamel, reversibility of treatment, and higher patient acceptance. However, the micro-veneer repair is suitable only for specific cases and must be strictly controlled regarding indication. Treatment planning is a crucial step to achieving functional and aesthetic rehabilitation, and following the clinical protocol is helpful for the longevity and success of micro-veneer restorations. However, more precise and predictable tooth preparation methods, such as minimally invasive microscopic tooth preparation and digitally guided veneer preparation, are recommended rather than the traditional free-hand method. Therefore, this paper clarifies micro-veneers and compares them with other restorations to gain a deeper and more comprehensive understanding. The authors also review indications, materials, cementation, and effect evaluation of micro-veneers to provide clinicians with valuable information. In conclusion, micro-veneers are minimally invasive treatments that provide good restoration results when used appropriately and are worthy of promotion for the aesthetic restoration of anterior teeth.

Esthetic rehabilitation with direct composite veneering: Two case reports

Introduction: One of the most common treatment modalities in routine dental practice is restoring patients aesthetic appearance. Discolorations of the anterior teeth are common and have a variety of causes. Composite veneering has grown in popularity in recent years, thanks to the concept of minimal tooth preparation and improved aesthetic properties of composite resins. Composite resin has been envisioned as an alternative treatment to ceramic laminates due to its low cost, reduced treatment time, and improved aesthetics. Direct veneers are created by directly applying a composite material to the prepared tooth surface.Case Report: This article presents two case reports of direct composite veneering of anterior teeth using direct composite veneering with a six-month follow-up that resulted in a satisfactory outcome.Conclusion: Both the aesthetic and functional outcomes were satisfactory. As a result, direct composite veneers can be considered as a cost-effective and time-saving alternative to ceramic veneers.

Lithium disilicate (IPS” e.Max computer-aided design) veneers for the esthetic rehabilitation in a young adolescent

Dental fluorosis is a developmental disturbance of enamel wherein the patients often present with esthetic concerns. Previously available approaches for the management of dental fluorosis included composite restoration, microabrasion, bleaching, resin infiltration and/or use of full crowns. For young permanent teeth, it is desirable to follow a treatment plan that efficiently addresses both anatomic and esthetic concerns. Keeping in mind, a minimally invasive approach, lithium disilicate in its modern formulations (IPSTM e.Max CAD) fabricates thin veneers with 0.1–0.7 mm thickness with greater fracture toughness and biaxial strength. Lithium disilicate has high esthetic properties, and the material requires minimal tooth preparation. The advent of newer technology has led to a period of evolution with esthetic dentistry leading the forefront. The present report elucidates a novel approach depicting the use of maximal esthetics (E-Max) lithium disilicate veneers in a young adolescent with moderate fluorosis to provide a minimally invasive esthetic outcome with 6 months' follow-up.

ESTHETIC MARYLAND BRIDGE: A SHORT REPORT

Missing teeth in the anterior region negatively impacts the patient’s appearance and adversely affects the patient’s selfconfidence. Various treatment options such as removable partial dentures, fixed partial dentures and implants are available to rehabilitate such loss. In this case report, a zirconia based esthetic resin bonded bridge was fabricated to replace the missing right anterior tooth temporarily for a young patient till he achieves the age when he can get permanent replacement. The procedure was done with minimal tooth preparation and the outcome was esthetic with superior bonding with resin cement. KEYWORDS: Maryland Bridge, Zirconia, aesthetics, anterior fixed partial dentures, Resin bonded partial dentures

English

An unpleasant smile can have a psychosocial effect leading to lack of self-esteem and a challenge in social relations. A perfect smile is a balance among 3 parameters: the white (teeth), the pink (gum) and the lips. A predictable smile correction warrants a multidisciplinary approach and good treatment planning. We planned for a minimally invasive interdisciplinary treatment approach for the restoration of a gummy smile with dental fluorosis in a young female patient. An interdisciplinary management of smile correction is crucial for successful results. Lasers for soft tissue management and minimal tooth preparation for direct composite veneer restorations being minimally invasive periodontal and restorative approaches were the key to success with exceptional patient satisfaction. Minimally invasive procedures in interdisciplinary dentistry should be embraced in the management of procedures requiring correction of both hard and soft tissues, for successful outcomes. Pre-treatment mock-up can build patients' confidence in dentistry and are useful tools for planning treatments with a predictable outcome. A beautiful smile is the fruit of a coordinated and balanced interplay between teeth, gingiva and lips. A compromise in any of these cornerstones can impair the beauty of a smile. Thorough knowledge and understanding about the various elements involved and their harmonious synchronisation makes smile makeovers a challenging task. One such challenge is the treatment of gummy smile. A gummy smile is a clinical condition that has gained tremendous focus and attention recently. Gummy smile is the excessive gingival display when a person smiles. It has been defined as a nonpathological condition causing aesthetic disharmony in which more than 3 mm of gingival tissue is exposed while smiling.1 Aetiology of a gummy smile can be multifactorial and the main factors being altered passive eruption (APE), vertical maxillary excess and upper lip hypermobility. The diagnosis must be accurate to deliver the appropriate line of treatment. Based on the complexity of the underlying aetiological factors involved, the treatment modalities also change from conservative approaches like aesthetic restorations and orthodontic tooth movements to periodontal and maxillofacial surgical procedures.2 Altered passive eruption (APE) also knows as “impaired passive eruption” is a clinical condition characterised by the coronally positioned marginal gingiva in relation to the cementoenamel junction (CEJ). Passive eruption is a physiological phase involved in the process of tooth eruption. As the teeth meet the occlusal plane, the soft tissue covering the teeth migrates apically till the CEJ is reached. Retardation in this process causes failure of the gingiva to migrate apically, resulting in short clinical crowns and excessive soft tissue exposure while smiling. This is visualised as a gummy smile.

Minimal tooth preparation for posterior monolithic ceramic crowns: Effect on the mechanical behavior, reliability and translucency

ObjectiveDespite the increased use of monolithic crowns, their performance has yet to be determined when the minimal tooth preparation (MTP) principle is considered. The goal of this study was to evaluate the effect of MTP on the mechanical behavior, reliability and translucency of posterior monolithic ceramic crowns. MethodsDentin analogues were machined using two preparation designs (0.5 or 1 mm reduction) to receive first molar crowns in order to evaluate the monolithic crown performance. Next, 126 crowns were divided (21/g) according to the material (High translucent zirconia – YZHT, Zirconia reinforced lithium silicate – ZLS and Hybrid ceramic – HC) and thickness (0.5 or 1 mm). Tensile stress concentration was calculated using the finite element method. The crowns were adhesivelly cemented and step stress fatigued to calculate reliability for missions at 600 and 1000 N. Translucency was analyzed in 10 discs of each material and thickness. ResultsHigher stress concentration was found in thinner crowns and those with higher elastic modulus. YZHT crowns were suspended when fatigue reached 1500 N load, thus 1-parameter Weibull was used to analyze the data. Reliability was only affected by thickness at 1000 N. ZLS.5 showed lower survival than HC.5, which was similar to the groups that presented 100% survival. YZHT showed the highest strength and data scattering. ZLS1 (22.3 ± 1.4) presented higher translucency than HC1 (19.2 ± 0.6) and YZHT1 (12.0 ± 2.9), whereas ZLS.5 and HC.5 were similar to each other (26.5 ± 2.3, 26.7 ± 2.2) and superior to YZHT.5 (12.7 ± 1.2). SignificanceHC.5 combined high reliability and translucency with low stress concentration, yielding better crown performance and tooth preservation.

Digital technologies to facilitate minimally invasive rehabilitation of a severely worn dentition: A dental technique

This technique report describes digital technologies to facilitate minimally invasive rehabilitation with computer-aided design and computer-aided manufacturing (CAD-CAM) veneers for a severely worn dentition. The lingual veneers without tooth preparation and occlusal veneers with minimal tooth preparation were designed from the digital scan of the interim restorations. To facilitate the cementation of multiunit lingual veneers on unprepared teeth, a custom 3D-printed guide was designed from the digital cast of the natural dentition with the lingual veneers. The guide reduced the technique sensitivity of freehand practice and allowed the verification of the complete seating of multiunit lingual veneers on unprepared teeth. The digital technique provided a valid and reliable approach to making and cementing multiple CAD-CAM veneers for the minimally invasive restoration of worn teeth.

Longevity of immediate rehabilitation with direct fiber reinforced composite fixed partial dentures after up to 9 years

ObjectivesThis retrospective, single-center, practice-based cohort study aimed to analyze the longevity of direct fiber reinforced composite fixed partial dentures (DFRC-FPD) and to analyze factors influencing their survival and success. MethodsWithin one private practice 100 DFRC-FPD were directly applied. The preparation of a proximal cavity was limited to abutment teeth with an existing filling (minimal-invasive approach). All intact enamel surfaces were preserved (micro-invasive approach). DFRC-FPD were reinforced by fiber-splints with semi polymer network matrices (Everstick C + B©). At the last follow-up DFRC-FPD were considered successful if they were still in function without any need of therapy. DFRC-FPD were considered as survived if they were repaired or replaced. Multi-level Cox proportional hazard models were used to evaluate the association between clinical factors and time. ResultsWithin a mean follow-up period (range) of 53 (2-109) months 7 bridges did not survive (cumulative survival rate: 93%) and further 24 bridges had received a restorative follow-up treatment (cumulative success rate: 69%). The annual failure rate was 1.6% for survival and 8.3% for success. The main failure type was fracture of the composite material (n = 30). In multivariate analysis no significant predictor could be found for success and survival. ConclusionsFor directly prepared fiber reinforced composite bridges high survival and moderate success times were observed after up to nine years. Based on the present results DFRC-FPD might be an immediate, short- to medium-term solution for replacing 1 to 2 missing teeth with no or minimal tooth preparation. Clinical significanceWithin the limitations of the present study DFRC-FPD offered an immediate, micro-/minimal-invasive, inexpensive short- and medium-term solution to replace missing teeth, even if no box-shaped proximal cavity was prepared.

An In Vitro Comparative Study to Assess Minimal Thickness Required for Monolithic Zirconia Crowns to Resist Fracture under Load on Rapid Prototyped Models

To evaluate and validate minimal thickness required for computer-aided designed (CAD) and computer-aided manufactured (CAM) monolithic zirconia crowns to withstand occlusal load. The study compares two systems. Forty-eight rapid prototype die models with varying occlusal reductions were fabricated. Group I samples had an axial wall height of 7.0 mm with occlusal reduction of 0.5 mm, group II had axial wall height 6.5 mm with occlusal reduction 1.0 mm, group III had axial wall height 6.0 mm with occlusal reduction of 1.5 mm. Control group IV had axial wall height 5.5 mm with occlusal reduction of 2.0 mm. Laboratories A (Czar) and B (3M) were provided with 24 samples each, 6 samples in each group for fabricating CAD/CAM monolithic zirconia crowns of 0.5, 1.0, 1.5, and 2 mm occlusal thickness, respectively, and cemented using resin-modified glass ionomer cement over the die models. Samples were loaded on a universal testing machine for fracture testing. Surface topography analysis of fractured specimens was done under the scanning electron microscope (SEM). The results were subjected to one-way analysis of variance (ANOVA) and honestly significant difference (HSD) Tukey test to analyze statistical significance at 0.05 levels. Samples of laboratory A performed superior to laboratory B. The t test showed fracture resistance of group AI (0.5 mm) > group BII (1.0 mm) and also group AIII (1.5 mm) > control of Lab B (2 mm). Monolithic zirconia crowns showed a favorable mechanical property to withstand occlusal load with minimal tooth preparation. The occlusal thickness of Czar with 0.5 mm is found to resist fracture under physiological masticatory load. Scanning electron microscope revealed increased voids in the microstructure of 3M, which lead to decreased fracture resistance. Preservation of tooth structure can be considered using monolithic crowns with minimal thickness of 1 mm.

Comparison of Microleakage of Pedo Jacket Crowns and Stainless Steel Crowns Cemented with Different Cements.

Objectives:This study aimed to assess the microleakage of Pedo Jacket crowns compared to stainless steel crowns (SSCs) cemented with different luting cements.Materials and Methods:In this in-vitro experimental study, 80 primary molars were randomly divided into four groups of 20 each. Groups 1 and 2 were subjected to standard tooth preparation for SSC. Crowns in group 1 were cemented with glass ionomer (GI), and crowns in group 2 were cemented with a resin-modified glass ionomer (RMGI) cement. In groups 3 and 4, minimal tooth preparation was performed for Pedo Jacket crowns, and the crowns were cemented with RMGI and Panavia resin cement, respectively. Microleakage was measured at mesial and distal surfaces in micrometers (μm), and the mean value for each tooth was calculated. Oneway analysis of variance (ANOVA) was applied to compare the microleakage of the four groups.Results:Group 3 (Pedo Jacket cemented with RMGI) showed the highest microleakage (1523.83±250.32 μm) with significant differences with the remaining three groups (P<0.001). Microleakage in group 4 (Pedo Jacket cemented with Panavia) was significantly lower than that in the other three groups (301.25±219.53 μm, P<0.001). Groups 1 (SSCs cemented with GI) and 2 (SSCs cemented with RMGI) were not significantly different in terms of microleakage (P=0.49) although group 1 showed slightly higher microleakage than group 2 (598.43±260.85 μm versus 500.25±124.74 μm).Conclusion:Pedo Jacket crowns can serve as an acceptable esthetic alternative to SSCs if cemented with resin cements.

Conservative anterior treatment with CAD-CAM technology and polymer-infiltrated ceramic for a child with amelogenesis imperfecta: A 2-year follow-up

Amelogenesis imperfecta is a genetic disorder that affects the structure of enamel and consequently the function, esthetics, and psychology of young patients. Restoring the dentition of a child with minimal tooth preparation is achievable with polymer-infiltrated ceramics. The treatment of a 12-year-old child presenting with amelogenesis imperfecta is described. An in-office computer-aided design and computer-aided manufacturing (CAD-CAM) system and polymer-infiltrated ceramic blocks were used in a noninvasive procedure. The definitive clinical outcome showed a major esthetic improvement and allowed for the normal eruption of the permanent dentition.

Three-Year Follow-Up of Diastema Closure Using Ceramic Veneers: A Case Report

The use of ceramic veneers has increased due to the minimal tooth preparation involved, the color and contour stability of the material, and the enhanced esthetics. They have proven to be an effective treatment option for managing esthetic and functional problems, especially in the anterior teeth. This paper aims to describe the esthetic management of anterior midline diastema and spacing in a 24-year-old female patient, using ceramic veneers.

Esthetic Rehabilitation of Retained Primary Teeth-A Conservative Approach.

With the advancement in ceramic restorations bonded to tooth structure, the treatment has become a feasible and conservative option to restore teeth with alteration in shape when owing to high demand in esthetics, with or without minimum tooth preparation. This article describes a report of a 32-year-old woman who was dissatisfied with her smile. The patient reported that she still had deciduous teeth, and that the maxillary lateral incisors had been restored with direct resin composite to correct the teeth shape. After discussing the restorative possibilities, a decision was made to place all-ceramic crowns (lithium disilicate glass-ceramic) with minimal tooth preparation, which figures as a conservative full-coverage approach. An esthetic outcome resembling a natural-looking smile resulted in the patient's satisfaction. Bonding of all-ceramic crowns onto minimally prepared deciduous teeth figures as a conservative treatment in case of partial anodontia, which decreases the chance of root resorption induced by trauma and benefits from good adhesion to enamel.

Three-Year Follow-Up of Diastema Closure Using Ceramic Veneers: A Case Report

The use of ceramic veneers has increased due to the minimal tooth preparation involved, the color and contour stability of the material, and the enhanced esthetics. They have proven to be an effective treatment option for managing esthetic and functional problems, especially in the anterior teeth. This paper aims to describe the esthetic management of anterior midline diastema and spacing in a 24-year-old female patient, using ceramic veneers.

3D quantification of clinical marginal and internal gap of porcelain laminate veneers with minimal and without tooth preparation and 2-year clinical evaluation.

The aims of this clinical study were to compare internal three-dimensional (3D) adaptation of porcelain laminate veneers (PLV) with minimal tooth preparation and without tooth preparation (prepless) and to evaluate the clinical outcomes at baseline and following 6, 12, and 24 months after luting. Thirty-one prepless PLV and 31 PLV with minimal tooth preparation were fabricated using lithium disilicate glass-ceramic material and placed in 12 patients (8 women, 4 men; 18 to 40 years old). All PLV were luted with an adhesive luting system (Variolink veneer). A silicone replica was obtained to measure internal adaptation of each PLV using a low viscosity polyvinyl siloxane impression material just before luting. Silicone replicas were scanned in x-ray micro computerized tomography (micro CT). Clinical evaluations took place at baseline (2 days after luting) and following 6, 12, and 24 months after luting. Marginal integrity, marginal discoloration, secondary caries, tooth sensitivity, and fracture were evaluated following FDI criteria. Replica scores were analyzed using Mann-Whitney U and Student's t test (α = .05). Kaplan-Meier statistical analysis was done for the survival rate of PLV. FDI criteria scores were analyzed using Pearson's chi-square test (α = .05). The median marginal gaps for PLV-without-tooth-preparation and PLV-with-minimal-tooth-preparation groups were 100 μm and 140 μm respectively. There was a statistically significant difference between the two groups with respect to marginal gap (P = .04). The mean internal adaptation for the PLV-without-tooth-preparation group was 217.17 ± 54.72 μm, and was 170.67 ± 46.54 μm for the PLV-with-minimaltooth- preparation group. There was a statistically significant difference between the two groups (P = .001). Based on FDI criteria, 100% of the PLV were rated satisfactory during the 2-year period. In this in-vivo study, mean and median values of marginal gap and internal adaptation for PLV with minimal tooth preparation and PLVs without tooth preparation were within a clinically acceptable range. A 100% success rate was recorded for all PLV during the 2-year period.

Survival characteristics of 771 resin-retained bridges provided at a UK dental teaching hospital.

To analyse the factors affecting the clinical performance and those influencing the survival of resin-retained bridgework provided at a UK dental teaching hospital between 1994 and 2001. A prospective analysis of restorations provided at a single centre using case notes with all patients invited for review to corroborate findings. Department of Restorative Dentistry, University of Bristol Dental Hospital and School, Bristol, United Kingdom. Between January 1994 and December 2001, data regarding 1,000 consecutive resin-retained bridges provided at Bristol Dental Hospital and School were recorded. Data was available for 805 patients at the time of the study. Following invitation, 621 patients attended for a review appointment. Life table and Kaplan-Meir survival analysis were carried out for all restorations provided. The five-year and ten-year survival rates estimated by the life-table method are 80.8% (95% confidence interval 78.0-83.6%) and 80.4% (95% confidence interval 77.6-83.2%) respectively. The median survival cannot be estimated for this study as the survival probability remains above 80% even at the longest follow-up. Analysis of clinical variables influencing survival revealed that design of the restoration and experience of the operator providing the restoration were significant factors. Resin-retained bridges made with minimal tooth preparation are shown to be superior in terms of longevity than those for which other types of tooth preparation is made. Patient satisfaction with their treatment was high.