The Outcome of Smoking on Healing of Bone Around Dental Implants.

Objectives: To assess the outcome of cigarette smoking and non-smoking on the healing of bone around dental implants. Materials and Method: A retrospective analysis was made over 6 years of the clinical and radiographic findings corresponding to 60 consecutive patients (25 women and 35 men) who had received a total of 100 implants. Patients were divided into two groups: smokers, 32 patients (received 50 implants); and non-smokers (NSs), 28 patients (received 50 implants). Smokers were identified as people smoking >15 cigarettes per day. The success and failure cases were evaluated and studied. The data were analyzed using descriptive statistics. Result: Smokers and NSs received 50 implants in each group with 5 (10%) and 2 (4%) failures and 90% and 96% of success in smokers and NSs, respectively. Smokers had a higher failure rate than NSs. The difference was statistically significant. Conclusion: The results indicated a higher success of implants in NSs compared to smokers.

Comparative Evaluation of Fracture Toughness and Flexural Strength of Four Different Core Build-up Materials: An In Vitro Study.

AIM: To evaluate and compare the fracture toughness and flexural strength of four different core build-up materials. MATERIALS AND METHODS: A total of 60 samples were divided into four groups (n = 15) group I: dual cure composite resin reinforced with zirconia particles (Luxacore Z), group II: light cure composite resin (Lumiglass DeepCure), group III: zirconia reinforced glass ionomer cement (GIC) (Zirconomer Improved), and group IV: chemically cure composite resin (Self Comp) respectively. All the core build-up materials were manipulated according to the manufacturer's instructions and poured into the mold. A universal testing machine applied a central load to the specimen in a 3-point bending mode. Fracture of the specimen was identified and the reading was recorded by the universal testing machine. The data were analyzed statistically using one-way analysis of variance (ANOVA) and then compared. RESULTS: Group I showed the highest flexural strength (48.65 MPa) among all the groups while group IV showed the lowest flexural strength (17.90 MPa). Group I showed the highest fracture toughness (99.12 MPa) among all the groups while group IV showed the lowest fracture toughness (36.41 MPa.cm-0.5). When mean flexural strength and fracture toughness values of all four groups were compared by using one-way ANOVA, the compared data was highly significant. CONCLUSION: Based on the findings of this study, dual cure composite resin was the material of choice in terms of flexural strength and fracture toughness for core build-up material followed by light cure composite resin. CLINICAL SIGNIFICANCE: The core buildup material serves to strengthen the tooth structure, allowing it to withstand the forces of chewing and preventing the risk of tooth fractures. This material is essential in restoring damaged or decayed teeth, as it provides a stable foundation for further dental work. By reinforcing the tooth structure, the core buildup material ensures that the tooth can function properly and remain healthy for years to come. How to cite this article: Nakade P, Thaore S, Bangar B, et al. Comparative Evaluation of Fracture Toughness and Flexural Strength of Four Different Core Build-up Materials: An In Vitro Study. J Contemp Dent Pract 2024;25(2):191-195.

Evaluation of the Influence of Build Orientation on the Surface Roughness and Flexural Strength of 3D-Printed Denture Base Resin and Its Comparison with CAD-CAM Milled Denture Base Resin.

OBJECTIVES: The purpose of this study was to determine the surface roughness and flexural strength of a three-dimensional (3D)-printed denture base resin printed with two different build plate orientations and to compare them with a computer-aided design-computer-aided manufacture (CAD-CAM) milled denture base resin. MATERIALS AND METHODS: Sixty-six specimens (n = 22/group) were prepared by 3D printing and CAD-CAM technology. The group A and B specimens were 3D-printed bar-shaped denture base specimens printed at 120-degree and 135-degree build orientation, respectively, whereas group C specimens were milled using a CAD-CAM technology. The surface roughness was assessed using a noncontact profilometer with a 0.01 mm resolution and the flexural strength was determined using a three-point bend test. The maximum load in Newtons (N) at fracture, the flexural stress (MPa), and strain (mm/mm) was also measured. STATISTICAL ANALYSIS: Data were analyzed by a statistical software package. One-way analysis of variance test was applied to determine whether significant differences existed among the study groups, followed by Bonferroni post-hoc test to determine which resin group significantly differed from the others in terms of flexural strength and surface roughness (p ≤ 0.05). RESULTS: The flexural stress (MPa) of group C was 200% of group A and 166% of group B. The flexural modulus was 192% of group A and 161% of group B. In contrast, group A had the lowest mean value among the three groups for all the parameters. No significant difference was seen between group A and group B. The mean roughness values of the CAD-CAM denture base resin specimens (group C) were the least (127356 nm) among all the three groups. The mean surface roughness of the 3D-printed denture base specimens (group A) was 1,34,234 nm and that of group B was (1,45,931 nm); however, it was statistically nonsignificant (p > 0.05) CONCLUSIONS: The CAD-CAM resin displayed superior surface and mechanical properties compared to the 3D-printed resin. The two different build plate angles did not have any significant effect on the surface roughness of the 3D-printed denture base resin.

Comparative Evaluation of Two Implant Designs Based on Bone Loss and Stability with Early Loading Method.

The study evaluated the implant bone loss and stability of implant changes with diverse designs with early placement at eight weeks and eight months' time. The subjects for the current study had partial tooth loss in the posterior mandibular arch. A total of 30 samples were split into two groups of 15, one with a flared crest module and a buttress thread design, the other with a parallel crest module and a V-shaped thread design. Ostell assessed each subject's implant stability four times, at baseline, eight weeks, four months, and eight months. At intervals of eight weeks, four months, and eight months, intraoral periapical radiographs were examined using ImageJ software to measure crestal bone loss. When Group I and Group II's implant stability quotient (ISQ) values at baseline, eight weeks, four months, and eight months were compared; Group I's ISQ values at each of the four measured time periods were statistically significant. At eight weeks in Group I, the ISQ value was very considerable. At eight weeks, four months, and eight months, there was a statistically significant bone loss in Group II in comparison to Group I. At eight months, Group II's bone loss value was very considerable. In contrast to Group II implant designs, it was found that Group I implants demonstrated enhanced implant-less bone loss and stability.