Assessment of Adaptability and Linear Dimensional Changes of Two Heat Cure Denture Base Resin with Different Cooling Techniques: An In Vitro Study

AIM

The current study was designed to assess the linear dimensional changes and adaptability of two heat-cured denture base resins using various cooling methods.

MATERIALS AND METHODS

To prepare a total of 90 acrylic resin samples (45 acrylic resin samples for each material), four rectangular stainless-steel plates measuring 25 × 25 × 10 mm were fabricated. For both groups, the material was put into the mold at the dough stage. Group I - SR Triplex Hot Heat Cure acrylic; group II - DPI Heat Cure acrylic. Both groups used the same curing procedure. One of the following three techniques was used to cool the material (15 samples from each material) once the curing cycle was finished: (A) water bath, (b) quenching, and (C) air. A traveling microscope was used to measure the distance between the markings on the acrylic samples. The data was recorded and statistically analyzed.

RESULTS

In SR Triplex Hot heat cure acrylic material, the maximum linear dimensional changes were found in the quenching technique (0.242 ± 0.05), followed by the air technique (0.168 ± 0.11) and the least was found in the water bath technique (0.146 ± 0.01). In DPI Heat Cure acrylic material, the maximum linear dimensional changes were found in the quenching technique (0.284 ± 0.09), followed by the air technique (0.172 ± 0.18) and the least was found in the water bath technique (0.158 ± 0.10). There was a statistically significant difference found between these three cooling techniques. On comparison of adaptability, the water bath technique, the marginal gap SR Triplex Hot was 0.012 ± 0.02 and DPI Heat Cure was 0.013 ± 0.02. In the quenching technique, the marginal gap SR Triplex Hot was 0.019 ± 0.04 and DPI Heat Cure was 0.016 ± 0.04. In the air technique, the marginal gap SR Triplex Hot was 0.017 ± 0.01 and DPI Heat Cure was 0.019 ± 0.01.

CONCLUSION

The present study concluded that among the different cooling methods, the water bath technique had the least linear dimensional change, followed by the air and quenching techniques. When comparing the materials, DPI Heat Cure acrylic resin showed a greater linear dimensional change than SR Triplex Hot heat cure acrylic resin.

CLINICAL SIGNIFICANCE

During polymerization, heat-cured acrylic resins experience dimensional changes. Shrinkage and expansion are dimensional changes that occur in heat-cured acrylic resins and have an impact on the occlusal relationship and denture fit. However, the denture base's material qualities and the different temperature variations it experiences during production may have an impact on this. How to cite this article: Kannaiyan K, Rathod A, Bhushan P, et al. Assessment of Adaptability and Linear Dimensional Changes of Two Heat Cure Denture Base Resin with Different Cooling Techniques: An In Vitro Study. J Contemp Dent Pract 2024;25(3):241-244.

Assessment of the Impact of Commonly used Beverages on Durability of Suture Materials: An In Vitro Study

Aim

The current study was conducted to evaluate the influence of frequently ingested beverages on the stability of suture materials.

Materials and Methods

This research comprised of two kinds of chromic catgut, polyglactin 910 (4-0) absorbable suture materials. Every specimen was subjected to tying using a square surgeon's knot. Subsequent to pretensioning, 80 suture samples (40 of every material) were employed in this research. Every specimen was subjected to immersion in artificial saliva to replicate the oral atmosphere. Specimens were sunken in the acidic drink (Coca Cola) and tea for 10 min every day. Tensile strengths of the suture specimens were subjected to test at particular time periods: before immersion and 1, 7, and 14 days after immersion. Tensile strength evaluation of the suture specimens was performed employing the microtensile tester at a cross-head speed of 2.0 mm/60 s.

Results

When subjected to exposure to acidic beverages, the tensile strength of chromic catgut suture before immersing was 25.14 ± 0.16, 25.02 ± 0.08 on the first day, 16.34 ± 0.23 on the seventh day, and 9.18 ± 0.28 on the fourteenth day. When the suture substance made contact with tea, the tensile strength before immersing was 24.48 ± 0.02, 24.14 ± 0.16 on the first day, 18.26 ± 0.11 on the seventh day, and 12.39 ± 0.14 on the fourteenth day. When subjected to exposure to acidic beverages, the tensile strength of polyglactin 910 sutures before immersing was 25.21 ± 0.02, 25.08 ± 0.01 on the first day, 18.12 ± 0.06 on the seventh day, and 10.06 ± 0.32 on the fourteenth day. When the suture substance made contact with tea, the tensile strength before immersing was 25.02 ± 0.14, 24.96 ± 0.04 on the first day, 20.48 ± 0.18 on the seventh day, and 14.10 ± 0.08 on the fourteenth day. The differences between the groups were statistically significant.

Conclusion

In conclusion, polyglactin 910 exhibited a maintained strength superior than chromic catgut sutures subsequent to 14 days.

A Study on Speech Analysis in Acquired Maxillary Defect Patients Treated with Maxillary Obturator

Aim

The aim of the present study was to assess the speech analysis in acquired maxillary defect patients treated with maxillary obturator.

Materials and Methods

Total of 16 patients were considered in the study. The age group of these patients ranged from 40 to 75 years with a mean age of 59.5 years, irrespective of their gender. The surgical obturator was fabricated using self-cure acrylic. The surgical obturator was delivered immediately after surgery. After a healing period of about 2 weeks, the surgical obturator was replaced by an interim prosthesis. This was processed with the help of heat-cure polymethylmethacrylate. The total number of patients was divided into two groups, namely, (A) Definitive obturator group and (B) Interim obturator group. The speech intelligibility (SI), was analyzed.

Results

The mean scores for SI before prosthesis in definitive and interim groups were 19.13 ± 3.22 and 19.87 ± 1.72, respectively. This was increased after prosthesis insertion to 24.38 ± 1.30 and 22.37 ± 1.18, which further increased after adaptation period of 2 months to 28.75 ± 1.28 and 24.62 ± 1.59 in two groups.

Conclusion

The present study concluded that speech was severely affected by maxillary resection and that rehabilitation with maxillary obturator was successful in restoring these aspects of speech.

Influence of Occlusal Stress on Implant Abutment Junction and Implant Bone Interface: A Finite Element Analysis Study

AIM

The aim of the present study was to assess the occlusal stress on the implant-abutment junction and implant-bone interface of a long-span implant-supported prosthesis made of two different prosthetic materials.

MATERIALS AND METHODS

A computerized tomography of the mandible was used to get the finite element model of the bone. The comparative groups were made as follows: S1 and S2 - 3.7 × 11 mm (44 region) and 4.5 × 11 mm (47 region), S1A and S2A - screw-retained porcelain-fused-to-metal prosthesis, S1B and S2B - cement-retained porcelain-fused-to-metal prosthesis, S1C and S2C - screw-retained zirconia prosthesis, and S1D - cement-retained zirconia prosthesis. Maximum stress generated on the implant-abutment interface of all the prostheses under vertical and oblique load was assessed.

RESULTS

For all the comparative groups, maximum level of stress was generated at the cervical level of the implant-bone interface in comparison to the apical and middle-third level under both vertical and oblique load. No statistically significant difference between zirconia and porcelain-fused-to-metal prosthesis was seen at the implant-abutment interface and the cervical third of the implant-bone interface. A significant difference was found between all screw-retained and cement-retained groups.

CONCLUSION

The present study concluded that the short implants in combination with standard-length implants using either porcelain-fused-to-metal or zirconia as prosthetic material in the form of long-span implant-supported prosthesis can be a viable treatment option in the posterior mandible.

CLINICAL SIGNIFICANCE

The accuracy of the diagnosis, examination, and knowledge of the site where the implant must be inserted, and the choice of superstructure is important for the stability and lifespan of the implant prosthesis.

Implementation of Anthropometric Measurements in Anterior Teeth Selection in Two Ethnic Groups: An In Vivo Study

Aim:

The aim of this study was to evaluate whether there is any consistent relationship between interalar distance and six maxillary anterior teeth in two ethnic groups.

Materials and Methods:

Two hundred subjects (Assamese 100 and Nyishi 100) of different age and sex ranging from 18 to 33 years were identified for this study. The distance between two widest points marked on the alae of nose was measured by means of sliding digital caliper. Statistical analysis of variance was the testing method to determine whether the nasal width and intercanine distance were different in various racial groups.

Results:

The mean nasal width dimension in Assamese group was 36.38 mm (range 28.55–50.00 mm). The mean nasal width dimension in Nyishi group was 35.73 mm (range 31.34–41.90 mm). For the nasal width, no significant difference was observed between two races. For the canine cusp tip to cusp tip distance, the mean value of Assamese subjects was 43.63 mm (range 39.02–50.02 mm), whereas the Nyishi presented 41.77 mm (range 36.69–47.05 mm).

Conclusion:

For the two racial groups studied, the measurements of the interalar width showed a weak correlation with the canine to canine distance, not sufficiently high to be used as a predictive factor. It suggests to select wider artificial teeth. Practitioners can use ethnic norms as guides, not absolute values.

Evaluation of oral health-related quality of life in patient with removable prosthesis: A cross-sectional study

Aim:

This study aimed to evaluate the relationship between oral health and quality of life in removable prosthesis users.

Materials and Methods:

An investigative cross-sectional study was designed, and 200 participants were considered based on calculations from the studies in the past. The Oral Health Impact Profile (OHIP)-14 survey comprises two parts in the study. Questions related to sociodemographic factors that documented age, gender, and type of removable prosthesis were included in the initial part of survey. Questions related to impact of oral health on quality of life make up the latter part of the survey. The answers ranged from “Definitely no” to “Definitely yes” for every item on a scale having 5 points. The likely range of scores is from 14 to 70. Data were analyzed by using the Statistical Package for the Social Sciences (SPSS) software program, version 20.0 for Windows. A value of P < 0.05 was considered statistically significant.

Results:

A survey evaluating the relationship between oral health and quality of life was adequately completed by 200 participants. Of these, 18 (22%) were women and 154 (78%) were men. The parameters such as gender, age, and the relationship between oral health and quality of life did not show significant difference either within groups or between the groups. The enrolled participants were wearing different dental prostheses such as complete dentures (CDs) in both upper (U) jaw and lower (L) jaw (19%), U jaw (3%), L jaw (4%) and removable prostheses in both jaws (30%), U jaw (24%) and L jaw (20%). No statistically significant differences were seen between them. The scores for oral health-related quality of life (OHRQoL) were associated positively with removable prosthesis score (r = 0.122) and were statistically significant.

Conclusion:

This study concluded that the use of removable prosthesis may positively impact OHRQoL. The period of usage of removable dentures was the highly significant parameter affecting patient gratification, whereas the practice of using removable prostheses was the highly significant parameter affecting the relationship between oral health and quality of life.

Evaluation of Different Pretreatment Efficacy with Fluoride-releasing Material on Shear Bond Strength of Orthodontic Bracket: An In Vitro Study

AIM

The aim of this study was to assess the efficacy of different pretreatments with fluoride-releasing material on shear bond strength (SBS) of orthodontic bracket.

MATERIALS AND METHODS

A total of 60 human mandibular premolars were taken in this study. These samples were stored in periodically changed distilled water at room temperature so as to stop bacterial growth. All samples were randomized to three pretreatment groups: group I, acid etching; group II, fluoride varnish; group III, casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) paste. Later, Transbond XT was applied on brackets made of stainless steel and brackets were centered buccally and then light-cured. The INSTRON universal machine was used to measure SBS. Based on the values, the adhesive remnant index (ARI) was estimated.

RESULTS

The maximum SBS was seen in group III (18.84 μ 1.04), followed by group II (14.18 μ 0.23), and the minimum bond strength was found in group I (13.90 μ 1.22). The one-way analysis of variance (ANOVA) showed high statistically significant difference within the pretreatment groups. The pretreatment group comparisons showed statistically significant difference between group I vs group III and group II vs group III. Score 0 was more in group III [8 (40%)] followed by group II [4 (20%)] and group I [2 (10%)]. The lowest number of score 3 was found in CPP-ACP paste group. After comparing the ARI scores within the groups, the Chi-square test showed a probability of 0.001 which was statistically significant.

CONCLUSION

Our study established that the CPP-ACP paste pretreatment improves the SBS of orthodontic bracket significantly followed by fluoride varnish and acid etching.

CLINICAL SIGNIFICANCE

The bond strength of orthodontic brackets that were bonded should be adequate to resist orthodontic forces applied during treatment. The effect of the adhesive material to improve the adequate bond strength depends on the efficient pretreatment methods.

Non-diabetic renal disease in type 2 diabetes mellitus: Study of renal - retinal relationship

Diabetic nephropathy (DN) has become the leading cause of end-stage renal disease worldwide. Non-diabetic renal disease (NDRD), is known to occur in diabetic patients. The renal and retinal relationship in type 2 diabetes mellitus (T2DM) with nephropathy is not uniform. This study was carried to study the histological spectrum of nephropathy in type 2 diabetic patients with proteinuria and its relationship with diabetic retinopathy (DR). Total 31 (males - 26; females - 5) proteinuric type 2 diabetic patients were studied. Average age of patients was 50.7 years. Nephrotic syndrome was noted in 21 (67.7%) patients. Overall, isolated DN, NDRD and NDRD superimposed on DN (mixed lesion) were observed in 12 (38.7%), 13 (41.9%) and 6 (19.4%) cases, respectively. DR was absent in 21/31 (67.7%) cases. The spectrum of nephropathy in patients without DR included: DN in 6 (28.57%), NDRD in 12 (57.14%) and mixed lesion in 3 (14.29%). Kidney histology in patients with DR (n-10) revealed DN in 6 (60%), NDRD in 1 (10%) and mixed lesion in 3 (30%) patients. Thus, absence of DR favors NDRD but does not exclude DN because isolated DN was noted in 28.57% cases in absence of DR. Similarly biopsy proven NDRD (pure NDRD; 10% and mixed lesion; 30%) was noted in 40% of cases in presence of DR. In summary, patients with T2DM had higher incidence of NDRD. DR is less frequent (32.3%) in type 2 diabetes and is a poor predictor of type of nephropathy. Hence, renal biopsy is essential for precise diagnosis of nephropathy in patients with T2DM.

Classic Kaposi's sarcoma in a Nepalese woman from a purportedly nonendemic area

Kaposis sarcoma (KS) occurs as four types; classic, endemic, immunosuppression-associated, and AIDS-associated. The presence of KS-associated herpesvirus (human herpesvirus 8) DNA in the tissue samples of 95% of all variants of KS has confirmed its role in the aetiopathogenesis of KS. It is now believed that these clinical variants most likely represent different manifestations of the same pathological process. Our case represents the first case of classic KS from our region.