Polymerization shrinkage of bonded resin composite restorations will result in the development of curing contraction stresses during setting and can cause debonding of the restoration or failure of the surrounding tooth structure. However, the hygroscopic expansion that occurs after exposure of the restorative to the wet oral environment can compensate for this shrinkage.
OBJECTIVE: The purpose of this study was to determine the hygroscopic expansion of six commercial resin composites and relate it to their composition, mechanical properties, shrinkage, and contraction stress development.
METHODS: Short-term volumetric shrinkage and contraction stress of the different composites were measured by mercury dilatometry and a universal testing machine. The long-term contraction stress was measured by the deflection of a bilayer strip of metal and a resin composite, which were stored dry as well as wet to determine the effect of hygroscopic expansion. The curvature of the strip was measured by profilometry over a period of 3 months.
RESULTS: The curvature of the strip correlated well (r2 =0.74) with the initial contraction stress, showing that the contraction stress is an important factor in initial deformation. The water sorption in all specimens showed that the initial deformation, within 2-4 weeks after curing, was completely counteracted. A high correlation (r2 =0.90) between deflection and relative water sorption was found, where the relative water sorption is defined as the absolute water sorption corrected for the inorganic filler volume of the composite.
CONCLUSIONS: Within a period of 2-4 weeks after curing most of the curing contraction stresses of resin composite restoratives will be released by hygroscopic expansion.

The purpose of this study was to evaluate the effect of the atmospheric pressure plasma treatment as a surface treatment method on the contact angle and shear bond strength (SBS) of zirconia ceramics and the failure mode between the self-adhesive resin luting agent and zirconia. The zirconia specimens were divided into eight groups based on the surface treatment method: alumina blasting, air plasma, argon plasma (AP), Katana cleaner, ozonated water, ozonated water+AP, Katana cleaner+AP, and tap water+AP. The contact angles, SBS, and fracture modes were tested. AP treatment significantly reduced the contact angle (p<0.0001). The combination of AP and other cleaning methods showed a higher bond strength and more mixed fractures. Our findings indicate that using atmospheric pressure plasma with argon gas, combined with other cleaning methods, results in a stronger bond than when using alumina blasting alone.

Focal microdontia is a dental anomaly characterized by the presence of a single abnormally small anterior or posterior tooth. The objective of this article is to provide an updated review of the literature on the advanced restorative management of focal microdontia, and to document a clinical case where the reviewed advanced restorative approaches were applied to treat a young adult presenting with a non-syndromic asymmetrical focal microdontia.We conducted a preliminary examination of the existing literature on the advanced restorative management of focal microdontia. Additionally, we presented a minimally invasive approach to the treatment of an 18-year-old female patient with non-syndromic asymmetrical focal microdontia. The primary advantage of adhesive dentistry is that it can better preserve the structure of smaller teeth. A review of literature reveals a paucity of reports on localized microdontia in the maxillary anterior region of the mouth. However, novel minimally invasive restorative procedures satisfy patients\' aesthetic and functional preferences. Well-executed additive diagnostic wax-ups and intraoral mock-ups can serve as a permanent restoration blueprint, providing predictable results for focal dental anomalies in the aesthetic zone. In conclusion, the use of minimally invasive dental approaches in young patients with focal microdontia can result in long-term satisfactory aesthetic outcomes.

OBJECTIVE: To determine whether water sorption and solubility of a recently introduced self-adhesive cement is comparable to two clinically tested resin composite cements after thermal aging, and if this is affected by the curing mode. Whether water sorption is correlated with color difference and biaxial flexural strength was also investigated.
METHODS: Water sorption and solubility of three resin composite cements {RelyX Universal (RUV), (Panavia V5 (PV5), Panavia SA plus (PSA)} were measured after thermal aging. Disk-shaped specimens were either light-cured or autopolymerized (n = 15 per group). Color difference ΔE00 and biaxial flexural strength were also obtained.
RESULTS: Sorption was highest for RUV (auto: 54.9 ± 9.0 µg/mm3, light: 49.7 ± 4.9 µg/mm3), followed by PSA (auto: 37.7 ± 1.4 µg/mm3, light: 34.5 ± 1.1 µg/mm3) and PV5 (auto: 21.7 ± 0.7 µg/mm3, light: 22.1 ± 0.4 µg/mm3). Light-curing reduced solubility values, particularly for RUV (from 60.7 ± 20.8 µg/mm3 to 6.4 ± 0.8 µg/mm3). Color differences of ΔE00 > 1.8 (considered clinically not acceptable) were noted after aging for RUV and PSA. Sorption and ΔE00 values after aging were correlated linearly (R2 = 0.970). Biaxial flexural strength values were highest for PV5 (light: 153.4 ± 15.9 MPa; auto: 133.2 ± 18.0 MPa) and lowest for RUV (light: 99.3 ± 12.8 MPa; auto: 35.1 ± 8.3 MPa).
CONCLUSIONS: Light-curing has beneficial effects on sorption, color stability, and biaxial flexural strength of resin composite cements. Cements containing 2-hydroxymethacrylate such as RUV and PSA are more prone to water sorption and color changes.

OBJECTIVE: This study aimed to investigate the effects of the age and sex of tooth donors on dentin bond strength.
METHODS: A total of 38 extracted teeth (12 male and 26 female donors; age range: 17-82 years) were used in this study. In addition to donor age and sex, four other microtensile bond strength (μTBS) test specimen factors were evaluated: dentin position, bonding area, presence of voids at the interface, and computed tomography (CT) values of dentin. The μTBS was measured immediately (24 h) and 6 months after storage in water. After the μTBS testing, linear mixed and nonlinear regression models were used to analyze the effects of these factors on the μTBS data.
RESULTS: The results from the linear mixed model revealed that the bonding area (P = 0.02), presence of voids at the interface (P = 0.04), and storage time (P < 0.001) significantly affected bond strength. In contrast, no correlation was observed between the μ TBS and dentin position (P = 0.08) or sex (P = 0.07). The results of the nonlinear regression model with robust variance-covariance estimators revealed that age significantly affected bond strength (P < 0.001). In addition, a significant positive correlation was found between μTBS and age (P < 0.001), with nonlinearity (P = 0.002). However, no correlation was observed between the μTBS and CT values (P = 0.69) without nonlinearity (P = 0.39).
CONCLUSIONS: These findings suggest that bond strength increases with age until 60 years but not afterward.

In recent years, tooth wear has been a growing concern in dentistry as it has become increasingly prevalent among the population. At the same time, the development of adhesive techniques has enabled minimally invasive treatment protocols, with the goal of preserving and protecting teeth for as long as possible. This clinical report presents the case of a full-mouth rehabilitation patient with tooth wear who was treated using minimally invasive techniques. Esthetic and functional outcomes were designed and monitored using digital tools such as digital impressions, 3D facial scans, a digital tooth library, transcutaneous electrical nerve stimulation (TENS), MRI, and kinesiographic (KS) analysis throughout the treatment. To increase the vertical dimension of occlusion, instead of using traditional centric relation (CR) methods, a myocentric relation (MCR) technique was employed. This approach allowed the clinician to maintain the occlusal Class I situation, avoiding more invasive orthodontic treatment or maxillofacial surgery and resulting in reduced morbidity, treatment time, and cost for the patient. At the 1-year follow-up, good patient adaptation was shown, suggesting that the MCR concept is a viable alternative to conventional CR methods in appropriate cases.

The aim of the present retrospective study was to evaluate the long-term results, including technical and biologic outcomes, of maxillary extended porcelain veneers with an incisal edge thickness above 2 mm.
Patients treated with extended porcelain veneers performed by a single clinician at University of Geneva between 1990 and 2003 were identified and invited to an examination. Of the 37 identified patients, 10 patients with 50 veneers agreed to be examined and were included. A clinical examination was performed to assess survival rates as well as technical and biologic outcomes (modified United States Public Health Services criteria). Patient records were also reviewed to retrieve patient and reconstruction data and every complication event. Patient-reported outcome measures (PROMs) were evaluated using a visual analog scale to measure esthetic satisfaction, functional and phonetic comfort, masticatory improvement, tooth sensitivity, and acceptance of restoration replacement in case of failure. Data were descriptively analyzed, and Kaplan-Meier survival estimators were computed for survival rates and complication events.
The survival rate of the veneers was 96% after a mean follow-up of 20.7 ± 3.7 years in function. The technical complication rate amounted to 30%, including two failures, nine repairable fractures, three cracks, and one displacement due to trauma. No cavitated caries lesions or endodontic complications were registered. PROMs were very high for esthetic satisfaction and phonetic comfort.
Within the limitations of the present retrospective study, extended porcelain veneers appear to be a successful long-term treatment option in terms of clinical outcomes and patient satisfaction.

Despite the clear advances regarding the restoration of posterior teeth, especially with the minimally invasive approach, there are still several topics where the available scientific evidence does not provide clear answers in terms of clinical decisions. The indications, differences, and clinical protocols for partial adhesive restorations (onlays, overlays, and endocrowns) and resistance form restorations (full-contour resistive crowns) were presented in Parts I and II of the present article series based on Coverage of susceptible cusps, Adhesion advantages and limitations, Resistance forms to be implemented, Esthetic concerns, and Subgingival management - the CARES concept. Now, in Part III, the focus is on different approaches of managing subgingival areas, gaining \"ferrule\" design, and the role of posts on the restorability strategies of severely compromised teeth.

OBJECTIVE: The study evaluated the clinical performance of partial indirect resin composite (PIRC) restorations with \"proximal box elevation\" (PBE) placed in molars.
METHODS: Sixty-three patients received 80 posterior PIRC (SR Nexco, Ivoclar Vivadent) restorations. Large posterior defects with cuspal loss and deep cervical margins were included in the study. PBE was performed prior to preparation and impression making. Two independent observers evaluated the restorations using the FDI criteria (scores 1-5) for esthetic, functional, and biological properties. Patients were recalled at 6 months and 1, 2, and 3 years. Overall success rates were calculated (Kaplan-Meier analysis) and compared (log-rank tests) according to baseline variables. The impact of the baseline variables on the failure of the restorations was analyzed (multiple proportional Cox regression).
RESULTS: Seventy-nine (98.7%), 69 (88.4%), 66 (92.9%), 44 (86.2%) and 45 (91.8%) PIRCs completed their follow up at baseline, 6 months, and 1, 2 and 3 years, respectively. In total, 10 failures were observed: 5 with partial loss, 4 with material chipping, and one with secondary caries, yielding an overall success rate of 87.5% and a survival rate of 93.8%, with a mean observation time of 26.5 ± 13.6 months.
CONCLUSIONS: PIRCs with PBE demonstrated a high survival rate and satisfactory esthetic properties. Failure was less likely for PIRC restorations with partial cuspal coverage (onlay) compared to full cuspal coverage (overlay).

OBJECTIVE: This narrative review aimed to survey the clinical outcomes of laminate veneers (LVs), including their survival and success rates.
METHODS: An electronic search of MEDLINE/PubMed, Web of Science, Cochrane Library, and Google Scholar from 2000 to April 2023 was conducted using the keywords \"laminate\" OR \"veneer\" OR \"porcelain\" OR \"feldspathic\" OR \"lithium disilicate\" OR \"composite resin\" OR \"zirconia\" OR \"survival\" OR \"success.\" Case reports, case series, reviews, abstracts, in vitro studies, and observational studies were excluded. Five researchers independently evaluated the titles and abstracts of all identified studies.
RESULTS: A total of 55 studies were identified. None of the studies met the criteria for zirconia LVs. According to the studies in this review, LVs fabricated with feldspathic porcelain, leucite-reinforced glass ceramics (LRG), and lithium disilicate ceramics (LDS) exhibited satisfactory survival and success rates. Furthermore, hydrofluoric acid etching followed by silane priming of the surface of ceramic LVs is necessary for improved clinical outcomes. The extent of dentin exposure significantly decreases the success rate of ceramic LVs. An appropriate adhesive luting process is required to achieve the long-term success of ceramic LVs. Dentin exposure should be minimized or sealed during tooth preparation to achieve a reliable and durable bond between LVs and abutment teeth.
CONCLUSIONS: Based on this narrative review of the literature, the use of silica-based ceramic feldspathic porcelain, LRG, and LDS is recommended for LVs.