Presence of mutans streptococci and Candida spp. in dental plaque/dentine of carious teeth and early childhood caries

This study determined the presence of mutans streptococci and Candida spp. in supragingival dental plaque and infected dentine of caries-free children, with early childhood caries and caries. Pooled samples of dental plaque and infected dentine were collected from 56 children aged 1-5 years, which were divided into 3 groups: early childhood caries (ECC); caries and caries-free. Infected dentine was collected in ECC and caries groups to compare the frequency of these microorganisms in the collected sites. The samples were inoculated in SB20 and SA medium, for mutans streptococci and Candida spp., respectively, and incubated at 37 degrees C for 48 h. Colony growth was verified and the identification was performed by biochemical tests and CHROMagar Candida. Fisher's test or chi-square (chi(2)) were applied (p=0.05). The more prevalent species were S. mutans and Candida albicans in ECC (85.4% and 60.4%, respectively), independently of the sample site. S. mutans only was significantly associated with carious teeth, whether in early childhood caries or not. However, the frequency of C. albicans in ECC was higher when compared to caries and caries-free groups. There is a significant association between the presence of C. albicans and early childhood caries.     

Coronally positioned flap with subepithelial connective tissue graft for root coverage: various indications and flap designs

Aesthetic concerns and functional abnormalities, such as dentin hypersensitivity, are often associated with gingival recession defects. Root coverage procedures aim to restore both gingival aesthetics and function in recession defects. The coronally positioned flap combined with the subepithelial connective tissue graft is one of the most widely used root coverage procedures. The present report illustrates four different indications where this procedure has been successfully employed. An isolated Miller class II recession defect associated with frenum pull, multiple adjacent Miller class I defects in the aesthetic zone, an isolated Miller class I defect associated with dentin hypersensitivity, and an isolated Miller class II defect on a retained deciduous tooth are the four diverse conditions treated by periodontal plastic surgery. Different approaches were used to create the coronally positioned flap. Treatment resulted in complete root coverage, resolution of hypersensitivity, and satisfaction of the patients' aesthetic concerns. An effective and predictable treatment modality, such as the coronally positioned flap combined with the subepithelial connective tissue graft, should be considered when treatment planning for gingival recession defects.     

Influence of various implant platform configurations on peri-implant tissue dimensions: an experimental study in dog

Aim: To evaluate the influence (i) of various implant platform configurations and (ii) of implant surface characteristics on peri‐implant tissue dimensions in a dog model. Material and methods: Mandibular premolars and first molars were extracted bilaterally in six Labrador dogs. After 3 months of healing, two implants, one with a turned and a second with a moderately rough surface, were installed on each side of the mandible in the premolar region. On the right side of the mandible, implants with a tapered and enlarged platform were used, while standard cylindrical implants were installed in the left side of the mandible. Abutments with the diameter of the cylindrical implants were used resulting in a mismatch of 0.25 mm at the tapered implant sites. The flaps were sutured to allow a non‐submerged healing. After 4 months, the animals were sacrificed and ground sections were obtained for histometric assessment. Results: All implants were completely osseointegrated. A minimal buccal bone resorption was observed for both implant configurations and surface topographies. Considering the animals as the statistical unit, no significant differences were found at the buccal aspect in relation to bone levels and soft tissue dimensions. The surface topographies did not influence the outcomes either. Conclusions: The present study failed to show differences in peri‐implant tissue dimensions when a mismatch of 0.25 mm from a tapered platform to an abutment was applied. The surface topographies influence a neither marginal bone resorption or peri‐implant soft tissue dimension. To cite this article:
Baffone GM, Botticelli D, Pantani F, Cardoso LC, Schweikert MT, Lang NP. Influence of various implant platform configurations on peri‐implant tissue dimensions: an experimental study in dog.
Clin. Oral Impl. Res. 22 , 2011; 438–444.     

A rationale method for evaluating unscrewing torque values of prosthetic screws in dental implants

Objectives

Previous studies that evaluated the torque needed for removing dental implant screws have not considered the manner of transfer of the occlusal loads in clinical settings. Instead, the torque used for removal was applied directly to the screw, and most of them omitted the possibility that the hexagon could limit the action of the occlusal load in the loosening of the screws. The present study proposes a method for evaluating the screw removal torque in an anti-rotational device independent way, creating an unscrewing load transfer to the entire assembly, not only to the screw.

Material and methods

Twenty hexagonal abutments without the hexagon in their bases were fixed with a screw to 20 dental implants. They were divided into two groups: Group 1 used titanium screws and Group 2 used titanium screws covered with a solid lubricant. A torque of 32 Ncm was applied to the screw and then a custom-made wrench was used for rotating the abutment counterclockwise, to loosen the screw. A digital torque meter recorded the torque required to loosen the abutment.

Results

There was a significant difference between the means of Group 1 (38.62±6.43 Ncm) and Group 2 (48.47±5.04 Ncm), with p=0.001.

Conclusion

This methodology was effective in comparing unscrewing torque values of the implant-abutment junction even with a limited sample size. It confirmed a previously shown significant difference between two types of screws.     

Patients' satisfaction after surgical facial reconstruction or after rehabilitation with maxillofacial prosthesis

The matching of the aesthetic, functional, and psychosocial results of a facial deformity may produce devastating effects in its carriers, especially if the lesion is extensive or the treatment is aggressive. Because of this, the objective of the present article was to evaluate patient's satisfaction rating after surgical facial reconstruction or rehabilitation with oral and maxillofacial prosthesis, by means of reviewing the literature.     

Ganglion cyst of the temporomandibular joint

Ganglion cysts of the temporomandibular joint are rare and arise from myxoid degeneration of die collagenous tissue of the capsule of the joint as a result of trauma.     

Evaluation of rat alveolar bone response to Angelus MTA or experimental light-cured mineral trioxide aggregate using fluorochromes

Introduction

The aim of this study was to evaluate the rat alveolar bone response after the implantation of experimental light-cured mineral trioxide aggregate (MTA) or Angelus MTA (Angelus, Londrina, Paraná, Brazil) by histological and fluorescence analysis.

Methods

Thirty Wistar Albino rats were divided into three groups. In the control group, empty polyethylene tubes were inserted into the rat alveolar sockets immediately after extraction. In the other groups, the tubes were filled with light-cured MTA or Angelus MTA. Five animals from each group were injected with calcein on day 7, alizarin on day 14, and oxytetracycline on day 21. On day 30, these animals were killed, and the right hemimaxillas were removed and histologically processed. Half of the maxillas were processed and stained with hematoxylin and eosin. The remaining maxillas were processed for fluorescence analysis and stained with Stevenel blue and alizarin red. New bone was histomorphometrically evaluated using a Merz grid.

Results

The light-cured MTA presented a similar response when compared with Angelus MTA; it was characterized by a mild inflammatory response and complete bone healing. In the light-cured MTA group, the fluorescence areas were more evident at 21 days, showing an increase in bone formation. However, dystrophic mineralization was observed only with Angelus MTA.

Conclusions

It was concluded that both materials present a similar inflammatory response and bone healing, but dystrophic mineralization was observed only with Angelus MTA.     

Sites of recurrence in oral and oropharyngeal cancers according to the treatment approach

OBJECTIVE: The purpose of this study is to evaluate the rates and the sites of tumour recurrence in patients with oral and oropharyngeal carcinomas. DESIGN: This is a retrospective study of a series of cases treated in a single institution. PATIENTS AND METHODS: A series of 2067 patients with oral and oropharyngeal squamous carcinoma, treated from 1954 to 1998 were analysed. The treatment approach was: surgery, 624 cases (30.2%); radiotherapy alone, 729 cases (35.3%); radiotherapy and surgery, 552 cases (26.7%) and radiotherapy and chemotherapy, 162 cases (7.8%). MAIN OUTCOME MEASURES: Tumour recurrence was observed in 1079 patients (52.2%): 561 cases of local recurrences (27.1%); 168 neck recurrences (8.1%); 252 locoregional recurrences (12.2%); 59, distant metastasis (2.9%) and 39 (1.9%), combination of distant metastasis with local, neck or locoregional recurrence. RESULTS: The rates of recurrence varied significantly according to the treatment performed. Oral cavity cancer patients undergoing radiotherapy alone or in combination with chemotherapy presented the highest rates of neck recurrences (22.5 and 40.0%, respectively) for clinical stage (CS) I/II and of local (41.2 and 30.1%) and locoregional (21.7 and 31.1%) recurrences for CS III/IV; yet, for CS III/IV, surgery without neck dissection was associated with the highest rates of neck recurrences (20.7%), but no differences were observed in the rates of local or locoregional recurrences for CS I/II patients. For oropharynx cancer patients with CS I/II there was no difference in the rate of locoregional failures according to the treatment. However, patients with CS III/IV undergoing radiotherapy present a highest rate of local (42.3%) and locoregional (28.8%) failures. CONCLUSION: The results suggest that surgery should be the first option for initial clinical stage oral and oropharyngeal cancers. For advanced cases independently of the site of the tumour, surgery and postoperative radiotherapy should be the standard of care because it is associated with the lowest rates of locoregional recurrence.     

ANTIMICROBIAL ACTIVITY OF SODIUM HYPOCHLORITE ASSOCIATED WITH INTRACANAL MEDICATION FOR Candida albicans AND Enterococcus faecalis INOCULATED IN ROOT CANALS

Objective:

The purpose of this study was to evaluate the action of sodium hypochlorite (NaOCl) associated with an intracanal medication against Candida albicans and Enterococcus faecalis inoculated in root canals.

Material and Methods:

Thirty-six human single-rooted teeth with single root canals were used. The canals were contaminated with C. albicans and E. faecalis for 21 days and were then instrumented with 1% NaOCl. The roots were divided into 3 groups (n=12) according to the intracanal medication applied: calcium hydroxide paste, 2% chlorhexidine (CHX) gel, and 2% CHX gel associated with calcium hydroxide. The following collections were made from the root canals: a) initial sample (IS): 21 days after contamination (control), b) S1: after instrumentation, c) S2: 14 days after intracanal medication placement; S3: 7 days after intracanal medication removal. The results were analyzed statistically by the Kruskal-Wallis test at 5% significance level.

Results and Conclusions:

Both 1% NaOCl irrigation and the intracanal medications were effective in eliminating E. faecalis and C. albicans inoculated in root canals.     

Comparative analysis between hard- and soft-filament toothbrushes related to plaque removal and gingival abrasion

OBJECTIVE: The aim of this split-mouth, examiner-blind study was to compare the dental plaque removal and incidence of gingival abrasion associated with the use of hard- and soft-filament toothbrushes. METHODOLOGY: The test group consisted of 20 non-dental students, mean age 25 years. After a three-day period of plaque accumulation following the use of a disclosing solution, the Quigley-Hein Plaque Index was recorded, while the presence of gingival abrasion was measured from photographs. Pairs of quadrants 1-3 and 2-4 were allocated to supervised brushing with hard- or soft-filament toothbrushes for 30 seconds, limited to the buccal aspects of the teeth. Plaque levels and gingival abrasion were again assessed. Initial and final values of the plaque index and the mean number of abrasions were compared with the Friedman and Wilcoxon tests (p < or = 0.05). RESULTS: Plaque indices were reduced significantly from a baseline of 4.12 in both groups to 1.21 after the use of hard-filament toothbrushes, and to 1.67 after the use of soft-filament toothbrushes. The use of hard-filament toothbrushes resulted in a significantly higher mean number of lesions when compared to the soft-filament toothbrushes; 11.6 and 7.9, respectively (p = 0.018). CONCLUSION: Hard-filament toothbrushes remove more plaque than soft filament brushes, but also cause a higher number of gingival abrasions.