Effect of low-level laser on bone defects treated with bovine or autogenous bone grafts: in vivo study in rat calvaria.

OBJECTIVE: The purpose of this study was to histologically evaluate the effect of low-level laser (LLL) on the healing of critical size defects (CSD) in rat calvaria, filled with autogenous or inorganic bovine bone grafts. METHODS: Sixty rats were divided into 6 groups (n = 10): C (control-filled with blood clot), LLL (low-level laser-GaAlAs, λ 780 nm, 100 mW, 210 J/cm(2), Φ 0.05 cm(2); 6 J/point), AB (autogenous bone), ABL (autogenous bone + low-level laser), OB (inorganic bovine bone), and OBL (inorganic bovine bone + LLL). MATERIAL AND METHODS: The animals were killed after 30 days. Histological and histometric analyses were performed by light microscopy. Results. The groups irradiated with laser, LLL (47.67% ± 8.66%), ABL (39.15% ± 16.72%), and OBL (48.57% ± 28.22%), presented greater area of new bone formation than groups C (9.96% ± 4.50%), AB (30.98% ± 16.59%), and OB (11.36% ± 7.89%), which were not irradiated. Moreover, they were significantly better than group C (Kruskal-Wallis test followed by Dunn test, P < 0.05). CONCLUSION: The laser accelerated the healing of bone defects and the resorption of particles of the graft material.

The effect of low-level laser on bone healing in critical size defects treated with or without autogenous bone graft: an experimental study in rat calvaria.

OBJECTIVE: The objective of this study was to evaluate the effect of low-level laser (LLL) on bone healing process in surgically created critical size defects in rat calvaria treated with or without autogenous bone graft (AB). MATERIAL AND METHODS: The study was conducted on 40 male rats (Rattusnorvegicus, albinus, Wistar), weighing 250-300 g. For accomplishment of the experimental procedures, the rats were anesthetized with an intramuscular injection of xylazine (0.02 ml/kg) and ketamine hydrochloride (0.4 ml/kg). Acritical size defect with 5-mm diameter was created. The animals were divided into four groups: Group C (Control- filled with blood clot), Group LLL, Group AB (autogenous bone graft), Group AB + LLL (autogenous bone graft and LLL). The animals treated with LLL received applications of LLL at the infrared spectrum wavelength (λ = 810 nm) and energy density of 6 J/cm(2) per point, 60 s per point, adding up to five points on the entire created defect. The animals were euthanized at 30 days postoperatively. After decalcification, each specimen was longitudinally divided into two blocks, exactly along the center of the original surgical defect, processed and embedded in paraffin. Longitudinal serial sections with 6-µm thickness were made, initiating from the center of the original surgical defect. The sections were stained with hematoxylin and eosin (HE) for light microscopy analysis for histomorphometric analysis. RESULTS: Group C presented smaller quantity of new bone formation than Groups LLL (P < 0.01), AB (P < 0.01), and AB + LLL (P < 0.01). CONCLUSIONS: Utilization of LLL favored the healing process in rat calvaria. The quantity of new bone formation with use of the LLL was similar to the autogenous bone graft.

Esthetic analysis of gingival components of smile and degree of satisfaction in individuals with cleft lip and palate.

OBJECTIVE: To evaluate soft tissue characteristics in individuals with cleft lip and palate and the degree of satisfaction of these individuals after rehabilitation. SETTING: Hospital for Rehabilitation of Craniofacial Anomalies, Brazil. PATIENTS: Forty-five individuals with repaired complete unilateral cleft lip and palate, aged 15 to 30 years. INTERVENTIONS: One hundred thirty-five frontal facial photographs were obtained at rest and in natural and forced smile. Specialists in periodontics evaluated the soft tissue characteristics. Both patients and specialists evaluated the smiles and scored them as esthetically unpleasant, acceptable, or pleasant. MAIN OUTCOME MEASURES: Comparison of the cleft area with the contralateral region was performed for evaluation of soft tissue. The results of the degree of satisfaction with smile were expressed as percentages and means. The findings between patients and periodontists experienced or inexperienced with cleft care were compared. RESULTS: Statistically significant differences were observed for alveolar process deficiency and absence of papilla in the esthetic area between groups (p < .05). Results show 84.4% of individuals considered their smile as esthetically pleasant. Specialists in periodontics of both groups scored the natural smile and forced smile as esthetically acceptable. There was a statistically significant difference in the mean of patients compared with both groups of specialists in periodontics (p < .05). CONCLUSIONS: Evaluation and knowledge of the soft tissue characteristics is extremely important for successful rehabilitation. The esthetic values and degree of patient satisfaction are essential for treatment success, since smile reconstruction should be esthetically pleasant to the patient.

Utilization of low-intensity laser during healing of free gingival grafts.

OBJECTIVES: This study evaluates the action of a low-intensity diode laser with gallium-aluminum-arsenide (GaAlAs) active medium on the healing process and analgesia in individuals undergoing free gingival grafts. MATERIAL AND METHOD: Ten individuals needing bilateral gingival graft in the mandibular arch were enrolled in a double-blind study. Each individual had a 30-d interval between the two surgeries. The side receiving application of laser was defined as test side and was established upon surgery; laser application was simulated on the control side. The laser was applied in the immediate postoperative period and after 48 h, and patients rated pain on a scale of 0 to 10, representing minimal and maximal pain, respectively. Photographs were obtained at 7, 15, 30, and 60 d postoperatively and evaluated by five periodontists. RESULTS: No statistically significant difference was found at any postoperative period between control and test sides, even though greater clinical improvement associated with treatment was observed at 15 d postoperative. At 30 and 60 d, some examiners observed the same or greater clinical improvement for the control. Only one individual reported mild to moderate pain on the first postoperative day. CONCLUSIONS: Low-intensity laser therapy did not improve the healing of gingival grafts and did not influence analgesia.

Evaluation of the effect of the GaAlAs laser on subgingival scaling and root planing.

OBJECTIVE: To evaluate the auxiliary effect of the low-intensity laser in subgingival scaling and root planing by analysis of its clinical aspects, as well as its analgesic potential during the procedure. BACKGROUND DATA: Despite the large number of studies conducted on low-intensity laser energy, few clinical studies are available on periodontics. MATERIALS AND METHODS: Ten patients were selected and submitted to measurement of six sites per tooth, four teeth per hemiarch (960 sites in all). All patients then received subgingival scaling and root planing. Besides periodontal treatment, the test side was also submitted to laser application. The analysis comprised measurement of probing depth, clinical attachment level, and gingival index. Laser energy was applied at a wavelength of 780 nm (35 J/cm(2), 70 mW, 20 sec per site) for preoperative analgesia, and scaling and root planing were performed with application of laser energy at a wavelength of 780 nm (35 J/cm(2), 70 mW, 20 sec) for analgesia, and at a wavelength of 630 nm (8.8 J/cm(2), 35 mW, 10 sec) for healing. The patients filled out a visual analogue scale to assess the pain they felt during the procedure. After 24 and 48 h, the laser was again applied at the wavelength of 630 nm, and the patients were re-evaluated after 3 d. RESULTS: There was a reduction in gingival inflammation, yet without a statistically significant difference between the study and control sides, both in clinical aspects and evaluation of pain during the procedure. CONCLUSION: Utilization of the diode laser as an auxiliary in subgingival scaling and root planing did not provide any apparent clinical benefit for teeth with shallow to moderate pockets.