Effect of enamel matrix proteins on the treatment of intrabony defects: a split-mouth randomized controlled trial study

The objective of this split-mouth, double-blind, randomized controlled trial was to compare the clinical effect of treatment of 2- or 3-wall intrabony defects with open flap debridement (OFD) combined or not with enamel matrix proteins (EMP). Thirteen volunteers were selected with one pair of or more intrabony defects and probing pocket depth (PPD) > or = 5 mm. All individuals received instructions regarding oral hygiene and were submitted to scaling and root planing. Each participant received the two treatment modalities: test sites were treated with OFD and EMP, and control sites received only OFD. After 6 months, a significant reduction was observed in PPD for the EMP group (from 6.42 +/- 1.08 mm to 2.67 +/- 1.15 mm) and for the OFD group (from 6.08 +/- 1.00 mm to 2.00 +/- 0.95 mm) (p < 0.0001), but with no significant difference between groups (p = 0.13). A significant gain in relative attachment level (RAL) was observed in both groups (EMP: from 13.42 +/- 1.88 mm to 10.75 +/- 2.26 mm, p < 0.001; OFD: from 12.42 +/- 1.98 mm to 10.58 +/- 2.23 mm, p = 0.013), but with no significant difference between groups (p = 0.85). Gingival recession (GR) was higher in the EMP group (from 1.08 +/- 1.50 mm to 2.33 +/- 1.43 mm; p = 0.0009) than in the OFD group (from 0.66 +/- 1.15 mm to 1.16 +/- 1.33 mm; p = 0.16), but this difference was not significant (p = 0.06). In conclusion, the results showed that OFD combined with EMP was not able to improve treatment of intrabony defects compared to OFD alone.     

Effect of two routes of administration of dexamethasone on pain, edema, and trismus in impacted lower third molar surgery

Purpose

The aim of the present study was to compare pain, edema, and trismus in the postoperative period following third molar surgery using 8?mg of dexamethasone administered either orally or through local injection.

Methods

A prospective, controlled, randomized trial was carried out involving 60 lower third molar surgeries in 67 patients between October 2008 and June 2009. The sample was randomly divided into three groups: group A (local injection), group B (tablets), and group C (control). In all cases, either ostectomy or crown sectioning was employed. On the second and seventh day following surgery, linear edema was determined using facial landmarks, and maximal mouth opening measurements were performed. Postoperative pain was recorded using a visual analog scale.

Results

Patient age ranged from 14 to 37?years (mean, 21.0?years). With regard to pain, edema, and trismus, the two administration routes tested (local injection and tablets) demonstrated similar efficacy, and both methods achieved better results in comparison to the control group.

Conclusion

Both the oral administration and local injection of dexamethasone proved effective in reducing pain, edema, and trismus compared to control group following lower third molar surgeries, achieving similar results.     

TGF alpha has low protein expression in nonsyndromic clefts

Genetic studies have demonstrated that nonsyndromic cleft is composed of two separate entities: the cleft palate only and cleft of the lip, alveolus with or without cleft palate; both have a heterogeneous genetic background and environmental factors contribute to the onset of these malformations. The role of transforming growth factor alpha (TGF-A) was considered possible, but conflicting results have been reported. To detect if TGF-A is involved in the onset of cleft diseases, a series of patients with nonsyndromic clefts and control subjects were analyzed with regard to protein expression. Forty-three patients with nonsyndromic clefts and 21 unaffected subjects were enrolled in this study. Paraffin-embedded specimens were matched with TGF-A antibody and then scanned with a computerized image analyzer. TGF-A was scored as absent, moderately (from 10% to 30%), and highly expressed in epithelium, gland, and muscle. Data were statistically analyzed with a Kruskal-Wallis test. Comparison between control subjects and patients with clefts showed that only gland and epithelium reached a significant P value. A subsequent comparison between cleft of the lip, alveolus with or without cleft palate and cleft palate only groups demonstrated a statistically significant difference only for gland. TGF-A was decreasingly expressed in unaffected, cleft of the lip, alveolus with or without cleft palate, and patient with cleft palate only and thus further strength has been given to its role in the onset of the disease.     

Scanning electron microscope assessment of several resharpening techniques on the cutting edges of Gracey curettes

AIM: Treatment of periodontal diseases is based on efficient scaling and root planing (SRP) and adequate maintenance of the patient. The effectiveness of SRP is influenced by operator skill, access to the subgingival area, root anatomy, and the quality and type of instrument used for SRP. The aim of this study was to evaluate the cutting edges of Gracey curettes after manufacturing and after resharpening using several techniques. METHODS AND MATERIAL: The cutting edges of a total of 41 new #5-6 stainless steel Gracey curettes were evaluated blindly using scanning electron microscopy (SEM). The quality of the cutting edges was evaluated blindly by a calibrated examiner using micrographs. Data were analyzed using a Kruskal Wallis test and non-parametric two-way multiple comparisons. RESULTS AND CONCLUSIONS: Different sharpening techniques had significantly different effects on the sharpness of cutting edges (p<0.05). Sharpening by passing the lateral face of curettes over a sharpening stone and then a #299 Arkansas stone produced a high frequency of smooth, sharp edges or slightly irregular edges between the lateral and coronal faces of the curettes. Sharpening by passing a blunt stone over the curette's lateral face produced the poorest quality cutting edge (a bevel). Sharpening of the coronal curette face produced extremely irregular cutting edges and non-functional wire edges. Sharpening with rotary devices produced extremely irregular cutting edges.     

Histologic evaluation of 3 retrieved immediately loaded implants after a 4-month period

OBJECTIVE: To perform a histologic and histomorphometric analysis of the peri-implant tissue reactions and bone-titanium interface in 3 immediately loaded (provisional loaded) titanium implants retrieved from a man after a loading period of 4 months. MATERIALS & METHODS: A 35-year-old patient with a maxillary partial edentulism did not want to wear a provisional removable prosthesis during the healing period. It was decided to insert 3 definitive implants and use 3 provisional implants for the transitional period. The provisional implants were loaded the same day with a resin prosthesis in occlusal contact. During the second surgical phase, after 4 months, the provisional prosthesis was removed, and the provisional implants were retrieved with a trephine bur. Before retrieval, all implants appeared to be clinically osseointegrated. The specimens were processed for observation under light microscopy. RESULTS: At low magnification, it was possible to observe that bone trabeculae were present around the implant. Areas of bone remodeling and haversian systems were present near the implant surface. Under polarized-light microscopy, it was possible to observe that in the coronal aspect of the thread, the lamellar bone showed lamellae that tended to run parallel to the implant surface, while in the inferior aspect of the thread, the bone lamellae ran perpendicular to the implant surface. CONCLUSIONS: Histologic data pertaining to these 3 immediately loaded implants, and retrieved after a 4-month loading period, show that immediate loading did not produce untoward effects on peri-implant bone healing.     

Intermittent cigarette smoke inhalation may affect bone volume around titanium implants in rats

BACKGROUND: A negative influence of smoking on implant outcomes has been reported. This animal study investigated the influence of cigarette smoke on osseointegration and newly formed bone within implant threads. METHODS: Male Wistar rats were included in the study. After anesthesia, the tibiae surface was exposed and a screw-shaped titanium implant (4.0 mm in length; 2.2 mm in diameter) was placed bilaterally. The animals were randomly assigned to group 1, control, or group 2, intermittent cigarette smoke inhalation. The animals were sacrificed after 60 days and undecalcified sections obtained. The degree of bone-to-implant contact (BIC) and the bone area (BA) within the implant threads were measured in the cortical (zone A) and cancellous bone (zone B) areas. RESULTS: A slight difference in the BIC was noted between the groups, but this was not statistically significant either in zone A or in zone B (Mann-Whitney test, P > 0.05). In contrast, the BA close to the implant significantly decreased in both zones for group 2 (84.73% +/- 4.77 versus 79.85% +/- 6.17, zone A in groups 1 and 2, respectively, and 32.01% +/- 6.62 versus 20.71% +/- 8.57, zone B in groups 1 and 2, respectively, P < 0.05). CONCLUSION: Within the limits of the present study, intermittent cigarette smoke inhalation may result in a poor bone quality around titanium implants inserted in rats.     

Outcome of 50 consecutive sinus lift operations

We report 50 patients who had sinus lift operations between 1995 and 1999 using different grafting materials [autologous bone, heterologous bone, and hydroxyapatite]. The casenote were analysed clinically (intraoperative and postoperative results and complications), radiographically (amount of augmented bone 6 months postoperatively), and histologically (quality of the new bone 12 months postoperatively). Our aim was to find out if the various bone grafting materials used resulted in different outcomes after adjustment for significant predictors. We found that hydroxyapatite was associated with the lowest rate of loss of grafted material (median, 2.4 mm) followed by the autologous bone from iliac crest (2.8 mm). Bovine bone shown the highest loss (3.3 mm).