Comparative evaluation of masticatory efficiency, clinical performance, and patient satisfaction of single implant-retained mandibular overdenture versus conventional complete denture: A prospective in vivo study.

AIM: The aim of this within-subject prospective clinical study was to investigate the scope of single implant mandibular overdenture by assessing its masticatory efficiency, clinical performance, and patient satisfaction compared to conventional complete dentures. SETTINGS AND DESIGN: Prospective In Vivo Study. MATERIAL AND METHODS: This prospective in vivo study was conducted in the Department of Prosthodontics and Crown and Bridge, Christian Dental College, Ludhiana. A total of 12 completely edentulous patients received a single implant in the mandibular anterior midline region. After the healing period, the conventional maxillary and mandibular dentures were fabricated. 15 days post insertion of the conventional dentures, patients were evaluated for masticatory efficiency, clinical performance including retention and stability, and patient satisfaction. To evaluate the masticatory efficiency blue raspberry and original pink "Hubba Bubba tape gum" were used as a test food. Colorimetric analysis was done to assess variance of hue. To assess clinical performance, retention, and stability of the mandibular denture was recorded using a digital force gauge and was tabulated as per CU-modified Kapur's criteria. OHIP-14 index was used to assess patient satisfaction. After evaluation of the parameters of conventional dentures, the denture was converted into an implant-retained mandibular denture by chairside conversion with locator attachments. 15 days post-implant loading, parameters of the implant retained mandibular overdenture were assessed again followed by statistical analysis. STATISTICAL ANALYSIS USED: The masticatory efficiency was assessed using a paired t-test. The patient satisfaction was sequentially assessed with Wilcoxon signed rank test and thereafter paired t-test was used to compare between conventional complete denture and overdenture. Clinical performance was assessed using the Wilcoxon signed rank test. RESULTS: The masticatory efficiency of single implant mandibular overdenture was higher than that of conventional complete dentures. The clinical performance of the overdenture was higher than that of the conventional denture. Stability being a time-dependent parameter might need longer follow-ups for further conclusions. Patient satisfaction with single implant retained overdenture was significantly higher than conventional complete dentures. CONCLUSION: Single implant mandibular overdenture has improved masticatory efficiency, clinical performance, and patient satisfaction compared to conventional complete dentures.

A comparative analysis of mechanical and optical behavioral patterns of translucent zirconia ceramics.

AIM: This research aimed to assess and compare the translucency and mechanical properties of partially stabilized zirconia in contrast to lithium disilicate, particularly within the context of translucent zirconia. SETTINGS AND DESIGN: The experimental design entails examining fifty samples, with ten drawn from each of the five distinct categories of ceramic materials, as part of this in vitro study. Translucency is measured using the Konica Minolta CM-3600D spectrophotometer, assessing Delta E through Lab values against white and black backgrounds. Flexural strength is analyzed via a 3-point bend test on a universal testing machine, with a controlled crosshead speed set at 1 mm/min. MATERIALS AND METHODS: The study included the five categories of ceramic materials, each consisting of ten samples: High-strength zirconia (Katana HT), translucent zirconia (e.max Zircad MT and Cercon ht ML), and lithium disilicate (Press MT and LT). The Konica Minolta CM-3600D spectrophotometer is utilized to measure the translucency parameter. This involves determining the color difference (Delta E) by comparing the L*a*b values against both white and black backgrounds. The flexural strength (FS) of zirconia and lithium disilicate materials was analyzed through a 3-point bend test, aiming to compare their respective strengths. The testing procedure was carried out on a universal testing machine with a controlled crosshead speed set at 1 mm/min. The FS was calculated using the formula σ = FL/πR3 for circular disks, where σ represents the FS, F is the fracture load, L is the span length in millimeters, and R is the radius of the disk. STATISTICAL ANALYSIS USED: The Student's t-test was employed for statistical analysis. RESULTS: The mean translucency parameter for e.max Press MT (6.33 ± 1.05) was significantly greater than all the specimens investigated. The Cercon ht ML exhibited a slightly higher translucency (2.18 ± 0.52) compared to e.max Zircad MT (1.49 ± 0.69), with a statistically significant difference (P = 0.022). Conversely, the FS of e.max Zircad MT (26.97 ± 2.06) was significantly greater (P < 0.001) than that of Cercon ht ML (23.25 ± 2.36). Notably, the Katana HT material demonstrated the highest load strength (32.92 ± 3.10), a statistically significant difference compared to its counterparts (P < 0.001). CONCLUSIONS: Among the materials tested, lithium disilicate ceramics exhibited the highest translucency, with its MT variant demonstrating the lowest strength. Katana HT displayed significantly greater biaxial FS compared to translucent zirconia, surpassing even lithium disilicate. Translucent zirconia proved to be notably more translucent than high-strength zirconia. Within the category of translucent zirconia, e.max Zircad MT exhibited substantially higher FS than Cercon.

Surface trueness and precision of interim restorations fabricated by digital light processing and CAD-CAM milling systems.

STATEMENT OF PROBLEM: The development of digital dental technologies has enabled clinicians to use additive and subtractive manufacturing techniques to fabricate interim restorations. However, knowledge of the trueness and precision of such restorations fabricated using digital light processing (DLP) and computer-aided design and computer-aided manufacturing (CAD-CAM) methods is limited. PURPOSE: The purpose of this in vitro study was to assess and compare the accuracy of interim crowns fabricated using DLP and CAD-CAM methods. MATERIAL AND METHODS: A typodont mandibular first molar was prepared for a ceramic crown, and a digital scan (Medit T500) was obtained to design interim crowns by using the CAD software program. The CAD data were designated as the reference data. A total of 20 crowns were fabricated by DLP and CAD-CAM technology. The fabricated interim crowns were further scanned using a laboratory scanner and were superimposed with the CAD data by using a 3-dimensional (3D) point cloud assessing software program (CloudCompare) for the evaluation of trueness and precision. Root mean square values (RMS) were obtained for the evaluation of discrepancies. The Student t test was used to compare data as the Shapiro-Wilk test confirmed the normal distribution. RESULTS: RMS values for the trueness values of the external and intaglio surfaces of the 3D printed and milled interim crown displayed no statistically significant differences (P>.05). Precision for the external surface reported significance (P<.05), whereas that for the intaglio surface reported no significance (P>.05). CONCLUSIONS: The accuracy of interim crowns fabricated by using DLP was comparable with that of milled crowns. Both manufacturing systems produced a true reproduction of the CAD. As for precision, the external surface of the DLP interim crown was statistically different from that of the milled group as it relates to the CAD.

Three-dimensional finite element analysis of zygomatic implants for rehabilitation of patients with a severely atrophic maxilla.

STATEMENT OF PROBLEM: Stresses applied to zygomatic implants have been determined to be transferred mainly to the zygomatic bone; however, consensus regarding the stress distribution pattern in the bone surrounding zygomatic implants has not yet been reached. PURPOSE: The purpose of this 3-dimensional (3D) finite element analysis (FEA) study was to visually compare the stress distribution pattern in 2 different zygomatic implant treatment modalities and evaluate the effect of masseter musculature involvement. MATERIAL AND METHODS: A 3D FEA craniofacial model was constructed from the computed tomography (CT) data of a selected patient with a severely atrophic edentulous maxilla. Modeled zygomatic and conventional implants were inserted into the craniofacial model supporting a prosthesis superstructure. Two types of treatment were considered in the study: 2 zygomatic implants placed bilaterally or 2 zygomatic implants placed in conjunction with at least 2 conventional implants at the anterior maxilla. The models were loaded with a vertical force of 150 N, a lateral force of 50 N, and a distributed occlusal force of 300 N applied to the insertion area of the masseter muscle. The stresses on and deformations of the bones and implants were then observed and compared with and without the involvement of the musculature component. RESULTS: The stresses were distributed efficiently along the vertical and horizontal facial buttresses, as in the dentate skull; however, a difference in distribution pattern was observed when the models were loaded without applying the muscle component. The maximum deformation of bones surrounding the implants occurred in the abutment connection of the conventional anterior implant in the model with an additional conventional anterior implant. CONCLUSIONS: The FEA revealed the stresses were distributed efficiently along the vertical and horizontal facial buttresses, as in the dentate skull. However, the stresses in both models were concentrated in the zygomatic bone when incorporating the muscle component. Therefore, incorporating muscular force into FEA studies could affect the analysis result.

Rehabilitation of the severely resorbed maxilla by using quad zygomatic implant-supported prostheses: a systematic review and meta-analysis.

STATEMENT OF PROBLEM: Quad zygomatic implants have been used as a treatment option for patients with a severely resorbed maxilla. However, data on the average rate of success of the prosthesis, survival of the zygomatic implants, and associated complications are sparse. PURPOSE: The purpose of this systematic review and meta-analysis was to assess prosthetic and zygomatic implant success of treating severe maxillary resorption with prostheses supported by 4 zygomatic implants, with an additional review on potential complications. MATERIAL AND METHODS: A comprehensive search of studies published in English between January 2001 and December 2020 was performed in the PubMed, OVID, EBSCO, and EMBASE databases according to the Preferred Reporting Items for Systematic reviews and Meta-analyses (PRISMA) guidelines. The study was registered in the International Prospective Register of Systematic Reviews (PROSPERO ID: CRD42021219468). The population, intervention, comparison, and outcome (PICO) question was "What is the effectiveness of oral rehabilitations using only 4 zygomatic implants placed in severely resorbed maxillae?" The search results were subjected to a systematic review for articles reporting prosthetic success and zygomatic implant survival. Prosthetic success was analyzed by using a fixed-effects inverse-variance model. The random-effects model was adopted for meta-analysis as moderate heterogeneity was identified among studies that reported implant survival in quad zygoma treatments. The quality of publications was appraised by using the Critical Appraisal Skills Program (CASP) checklists. RESULTS: Of the 82 titles, 7 studies that met the inclusion criteria without an overlap of patient cohorts were quantitatively analyzed for the average rate of prosthetic success and implant survival. All prostheses in the aggregated studies were immediately loaded with acrylic resin interim prostheses replaced by a definitive prosthesis, which consisted of overdentures retained by bar splinting (n=2), metal bar-reinforced prostheses (n=2), fixed screw-retained acrylic resin prostheses (n=34), and screw-retained titanium prostheses with ceramic or acrylic resin teeth (n=75). Technical complications of zygomatic implants included mobility associated with a machined surface and fracture of the abutment screw. The most common prosthetic complications reported were fracture of the definitive prosthesis and loss of the interim prosthesis subsequent to the failure of at least 1 zygomatic implant. The results showed that prostheses supported by quad zygoma implants displayed an overall success of 100% (CI=95%, I2=0.00%, P=.850), whereas zygomatic implants showed a survival rate of 98% (CI=95%, I2=60.48%, P=.040) with minimal implant failures and few complications. CONCLUSIONS: Although the data analysis showed favorable results for rehabilitating severely resorbed maxillae by using quad zygoma with high prosthetic success and high implant survival rate, further long-term clinical studies are required to strengthen the evidence. However, potential implant and prosthetic complications should be considered while planning this treatment approach.

A 10-year (2010 to 2019) scientometric analysis of prosthodontic journals based on SCImago Journal and Country Rank indicators.

STATEMENT OF PROBLEM: Scientometrics is the study of measuring and analyzing scholarly literature. Scientometric analysis to determine the impact of prosthodontic journals on scientific contributions is lacking. PURPOSE: The purpose of this analysis was to compare the quality of prosthodontic journals based on performance indicators over 10 years (2010 to 2019). MATERIAL AND METHODS: The SCImago Journal and Country Rank portal was used to identify various prosthodontic journals under the subject of dentistry. Seven journals publishing in the English language with "Prosthetics" and "Prosthodontics" in the title were identified and analyzed. The statistical analyses of the scientometric indicators for the 7 highest-ranked journals were performed with 1-way analysis of variance (ANOVA) and the Tukey post hoc tests (α=.05). RESULTS: The absolute SCImago journal rank (SJR) was highest at various time periods for the Journal of Prosthetic Dentistry (JPD), International Journal of Prosthodontics (IJP), and Journal of Prosthodontic Research (JPR). The JPD and IJP scored higher SJR than other journals during this period (P<.05). The mean cites per document and the h-index were highest for JPD (P<.05). CONCLUSIONS: Scientometric tools enable the evaluation of journal performance to aid researchers when choosing a journal to which to submit their work. Analysis of the 7 prosthodontic journals revealed the performance of various journals and gives an insight into the journal characteristics for future researchers who wish to submit their scholarly work.

Zygomatic implant-supported prosthetic rehabilitation of a patient with Brown et al. Class II c maxillary defect: A clinical report.

The genesis of acquired maxillary defects poses a significant challenge when it comes to rehabilitating a patient prosthetically. These defects lead to functional and esthetic impairment, affecting the quality of life of an individual. This clinical report describes a satisfactory zygomatic implant-supported overdenture rehabilitation of a patient who underwent subtotal bilateral maxillectomy after an industrial accident. The result shows zygomatic implant-supported overdenture as a viable, predictable, and economical treatment option for a patient with an extensive maxillary defect.

Prosthodontic rehabilitation of a sub-total maxillectomy defect with a definitive hollow obturator prosthesis using the modified lost-wax concept: A novel technique.

Squamous cell carcinoma (SCC) of the oral cavity is relatively common in the Indian subcontinent with surgical resection and adjuvant radiotherapy/chemotherapy being the treatment modality of choice. Prosthetic rehabilitation with an obturator following resection is more economical and yields satisfactory results. Better patient acceptance and comfort necessitates hollowing the prosthesis to a great extent. This novel method modifies the existing lost-wax technique in fabricating a definitive hollow maxillary obturator. An elderly man had reported to the Department of Prosthodontics with the chief complaint of a "big hole" in the mouth which affected his quality of life. He had undergone subtotal maxillectomy, following a histopathologic diagnosis of SCC, with adjuvant radiotherapy. Examination revealed an Aramany Class II defect with the healthy oral mucosa. A lightweight definitive obturator was designed and fabricated using a simple technique which utilizes easily available modeling wax. This article describes a relatively simple, single-step fabrication of a closed hollow-bulb obturator prosthesis with a uniform thickness of heat-cured resin encapsulating the hollow prosthesis.

Evaluation of Surface Microhardness Following Chemical and Microwave Disinfection of Commercially Available Acrylic Resin Denture Teeth.

INTRODUCTION: Denture disinfection is an indispensable procedure for preventing cross contamination and the maintenance of a healthy oral mucosa in patients rehabilitated with removable dental prosthesis. Nevertheless, they are known to cause changes in the physical and mechanical properties of denture base resins and acrylic resin denture teeth following immersion of a denture in a suitable chemical disinfectant solution or by undergoing microwave irradiation. One such mechanical property indicator for artificial tooth materials is hardness. AIM: To assess the surface hardness of acrylic resin teeth of three different commercial brands (Ivoclar, Newace, Acryrock) following chemical (2% glutaraldehyde, 1% sodium hypochlorite) and microwave disinfections. MATERIALS AND METHODS: Ten specimens of each of the three commercial brands were made for control and each simulated disinfection type and stored in distilled water at room temperature for 24 hours. After water storage, specimens were immersed in 2% glutaraldehyde and 1% sodium hypochlorite (one and three cycles) at room temperature for 10 minutes. Irradiation with microwave (one and three cycles) was done in domestic microwave for three minutes with the specimens immersed in 150 ml of distilled water. The specimens were stored in distilled water at room temperature for seven days after each disinfection cycle. Vickers hardness measurements were made using a hardness indenter under a load of 50 g force for 10 seconds. Data was subjected to repeated measure two-way ANOVA test and Tukey's test. RESULTS: There were statistically significant differences for the variables disinfection, tooth, and cycle (p<0.05 for teeth & disinfectant interaction, p<0.05 cycle and disinfectant interaction). The mean surface hardness following one microwave disinfection cycle was lower than control, glutaraldehyde and sodium hypochlorite. Comparison among cycles revealed that microhardness was significantly decreased for three cycles of microwave disinfection. CONCLUSION: It was concluded that there was no significant difference in microhardness when the teeth were subjected to chemical disinfection but three cycles of microwave disinfection produced decrease in the microhardness of different types of artificial teeth.

Fine needle aspiration cytology: a diagnostic aid for oral lesions.

PURPOSE: Oral lesions usually lead to a diagnostic dilemma. Fine needle aspiration cytology (FNAC) is an important diagnostic aid for making a preoperative diagnosis of oral lesions. It does not supplant histopathology but augments it. MATERIALS AND METHODS: FNAC of oral lesions was undertaken in 45 patients, and all the lesions were subjected to histopathologic examination. Aspiration was performed with 23- to 25-gauge needles held in a Cameco syringe holder (Amar Udyog, Chandigarh, India). RESULTS: We diagnosed benign lesions in 22 cases, malignant lesions in 15, and inflammatory lesions in 7 by FNAC, whereas in 1 case the specimen was insufficient for diagnosis. One result was false negative, but there was no false-positive result. Specificity and sensitivity of FNAC were 95.45% and 93.75%, respectively. FNAC gave a diagnostic accuracy of 90.0% for benign lesions, 94.0% for malignant lesions, and 100% for inflammatory lesions. CONCLUSION: The procedure does not have any side effects or complications. Hence FNAC can be used as a reliable diagnostic aid for oral lesions because it is safe, accurate, convenient, and cost-effective.

Displacement of endodontic instruments in inferior alveolar canal.

Endodontic instrument breakage is a common occurrence during root canal treatment but the displacement of the separated instrument into the inferior alveolar canal is rare and has never been reported. We hereby present an unusual case of displacement of a separated instrument in the inferior alveolar canal and its retrieval by a simple technique.