Evaluation and Comparison of the Effect of Different Border Molding Materials on Complete Denture Retention: An in vivo Study

AIM

Different border molding materials have different qualities which help in recording fine details of tissues. The present study was conducted to evaluate and compare the effect of different border molding materials on complete denture retention.

MATERIALS AND METHODS

The present study was conducted on 10 completely edentulous patients in the age group of 50 to 70 years. On each patient, three different border moldings were completed. In group I, border molding was done with green stick impression compound. In group II, border molding was done with putty consistency addition silicone. In group III, border molding and final impression were done by polyether impression material in a single step. Permanent denture bases were fabricated with wire loop at the center. Retention was assessed in all three groups using a digital force gauge.

RESULTS

Upon data compilation and preparation of spread sheets for concerned groups, it was subjected to statistical analysis using Statistical Package for the Social Sciences (SPSS) software version 21.0 for Windows. Mean age ± standard deviation (SD) was 57.40 ± 8.46 in group I, 57.40 ± 8.46 in group II, and 57.40 ± 8.46 in group III. The difference was nonsignificant (p > 0.05). The overall mean value for the group I was 4.59 ± 0.81. For group II, it was 4.7 ± 0.81. For group III, it was 6.72 ± 0.81. The difference was significant (p < 0.05).

CONCLUSION

Green stick compound with light body final wash showed the lowest mean values of complete denture retention. Dentures made using polyether final impression material showed the highest mean values of complete denture retention followed by putty rubber base border molding with light body final wash.

CLINICAL SIGNIFICANCE

In this study, polyether showed the highest mean retentive value compared with other tested materials; therefore, it could possibly provide some future innovative means in achieving optimal denture retention.

Evaluation of Predictability of Suitable Implant Lengths as related to Accurate Treatment Planning using Recent Roentgenographic Measures: A Key to Success

BACKGROUND AND AIM

Selection of suitable length of dental implants is very subjective and largely depends on clinical evidences and operator's expertise. The present study was aimed to assess the role of cone beam computed tomography (CBCT) and cephalograms as far as the selection of right implant length is concerned.

MATERIALS AND METHODS

The study includes 220 patients for whom radiographic and follow-up records were obtained. There were 105 males and 115 females in the age range of 22 to 58 years. A total of 98 implant sites in different edentulous areas were studied. Length of implant was predicted at treatment planning and compared with finally placed implant at surgical stages. It also includes the in-depth exploration of (1) number of implants placed per patient, (2) implant per edentulous areas, (3) implant location, and (4) implant region. For prediction of implant lengths, CBCT results were obtained and compared with cephalometric findings. Accuracies of implant lengths as planned by CBCT and cephalometric images were also studied at treatment planning and surgical stages. Statistical analysis and results: Upon statistical comparisons, we found that larger implant lengths chosen at treatment planning stage did not change in 65.5% of patients. In addition, the smaller length implants were just about the same as that with larger dimensions. The CBCT results were satisfactory (up to 98.5%). Cephalometry was performed well in this prediction, especially in posterior mandible (87.9%). However, its performance in anterior maxillary region was not satisfactory (69.6%). Intergroup comparisons of CBCT and cephalometric results at different regions were significant (p < 0.001).

CONCLUSION

Our study results show insignificant changes in the length of implants that was exactly planned using CBCT scans. Therefore, accurate prediction of implant lengths can be done using CBCT scans as they have superior and advanced tools that facilitate presurgical decision-making. Lateral cephalometric evaluation has been shown as an imperative radiographic tool for determining implant lengths as it confirmed the significance bone resorption on the selection of implant length at different sites.

CLINICAL SIGNIFICANCE

The CBCT and lateral cephalogram offer excellent anatomical details that can be judiciously applied for treatment planning and other clinical decision-making, including selection of correct implant length. Our study advocates thorough cephalometric evaluations of mandible wherein implants are to be placed for implant-supported overdentures.

Evaluation of the Efficacy of Different Mixing Techniques and Disinfection on Microbial Colonization of Polyether Impression Materials: A Comparative Study

AIM

This study aims to determine the role of mixing techniques of polyether impression materials and efficacy of disinfection on microbial colonization of these impression materials.

MATERIALS AND METHODS

Polyether impression material was mixed using two methods: First by hand mixing (group I) and second using an automixer (group II) with a total of 100 samples. Four microbial strains were studied, which included Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans. After incubation, the bacterial colonies were counted, and then, disinfectant solution was applied. The effect of disinfection solution was evaluated for each specimen.

RESULTS

The surface of polyether impression materials mixed with an automixer has less number of voids and overall a smoother surface as compared with the hand-mixed ones. On comparing the disinfection procedures, i.e., specimens without any disinfection and specimens after disinfection, statistically highly significant difference was seen between all the groups.

CONCLUSION

We can conclude that impression mixing procedures are important in determining the surface characteristics of the impression and ultimately the colonization of bacteria and also determine the importance of disinfection on microbial colonization.

CLINICAL SIGNIFICANCE

This study emphasises the deleterious role of nosocomial infections and specific measures that should be taken regarding the prevention of such diseases. Dental impressions are proved to be a source of such infections and may lead to transmission of such diseases. Thus, proper measures should be taken right from the first step of impression taking to minimizing and preventing such kind of contaminations in clinical practice.

Measurement of Crestal Cortical Bone Thickness at Implant Site: A Cone Beam Computed Tomography Study

AIM

Dental implants have emerged as a new treatment modality for the majority of patients complaining of missing teeth. Bone quantity and bone quality are among various factors which ensure the longevity of dental implant in the patient's mouth. The assessment of cortical bone thickness of the outer layer and the cancellous bone density by cone beam computed tomography (CBCT) has proved beneficial for the patient. This study aimed at presurgical measurement of crestal bone thickness at various implant sites using CBCT images.

MATERIALS AND METHODS

This study was conducted in the Department of Prosthodontics in the year 2015. It included 218 patients who wanted to replace missing teeth. Patients were subjected to CBCT scan using NewTom CBCT machine operating at 120 kVp and 5 mA with a resolution of 0.1 × 0.1 × 0.1 mm³. New Net Technologies (NNT) software with a slice thickness of 0.1 mm was used in this study. A total of 780 implant sites were identified on images of 218 patients. In all patients, the measurement of crestal bone thickness in the region of implant site was performed with NNT software. The buccolingual measurement of crestal bone was done in cross sections obtained after CBCT Results: Out of 218 patients, males were 110 and females were 108. The difference between gender was nonsignificant (p > 0.05). Out of 780 implant sites, 370 were in the maxilla and 410 were in mandible. The difference was nonsignificant (p > 0.05). Out of 780 implant sites, 210 were in anterior maxilla and 160 were in the posterior maxilla. Totally, 235 sites were in anterior mandible and 175 were in the posterior mandible. The distribution was nonsignificant (p = 0.15). The mean crestal bone thickness in anterior maxilla was 0.82 mm, in posterior maxilla was 0.76 mm, in anterior mandible was 1.08 mm, and in posterior mandible was 1.18 mm. The difference among regions was significant (p = 0.01).

CONCLUSION

The highest thickness of cortical bone was observed in posterior mandible followed by anterior mandible, anterior maxilla, and posterior maxilla. Thus, considering the less cortical thickness in the posterior maxillary region, the implant placement should be done with proper attention.

CLINICAL SIGNIFICANCE

Dental implant is the need of the hour. It is beneficial to patients in terms of longer survival rates. With CBCT, all measurements, such as bone quality and quantity have become easy because of three-dimensional nature. This has proved to be beneficial in the analysis of cortical bone thickness as well as measuring the distance from anatomical structures.