The Effect of Application of Combined Bovine-Derived Anorganic Bone Graft and Hemostatic Plant Extract on Bone Regeneration.

PURPOSE: To evaluate the effect of bovine-derived anorganic bone graft (ABB) in combination with hemostatic plant extract (ABS) on bone regeneration. MATERIALS AND METHODS: Three bone defects were created via an extraoral approach on the mandibles of nine domestic pigs. The first defects were filled with ABS solution (0.3 mL/defect) in a transporting agent of ABB (0.3 cc/defect), whereas the second defects were filled with ABS (0.3 mL/defect) in microcapsules for controlled drug release, combined with ABB (0.3 cc/defect) again. The third defects were left empty. After a 10-week healing period and the sacrification, undecalcified sections were prepared for histomorphometric analysis. RESULTS: The mean total area of hard tissue was 29.54% ± 3.2% in the control group, 59.78% ± 5.4% in the conventional group, and 63.67% ± 4.2% in the microsphere group (P < .001). The mean area of newly formed bone was 29.54% ± 3.2% in the control group, 34.79% ± 3.9% in the conventional group, and 37.95% ± 5.3% in the microsphere group (P = .003). The mean residual graft area was 24.99% ± 2.4% in the conventional group and 25.71% ± 4.4% in the microsphere group (P = .730). CONCLUSION: The combined usage of ABS and ABB in both ways increased bone regeneration statistically. However, there was no significant difference between the two methods for ABS delivery systems in terms of new bone regeneration.

Effects of Orthognathic Surgery on Voice Characteristics.

PURPOSE: Orthognathic surgery not only corrects dentofacial deformities but also affects some vital structures involving voice production. The primary aim of this study was to analyze the effects of bimaxillary orthognathic surgery on voice characteristics of patients with class II and III skeletal deformities; the second aim was to evaluate possible associations among acoustic parameters, pharyngeal airway, and skeletal changes after surgery. MATERIALS AND METHODS: Using a prospective cohort study design, we enrolled a sample of patients who underwent bimaxillary orthognathic surgery in the university hospital between January 2018 and January 2019. Voice records and cone-beam computed tomography (CBCT) scans of the patients were acquired before surgery and 6 months after surgery. Pharyngeal airway volume, minimum cross-sectional area, hyoid bone position, and skeletal movements of the maxilla and mandible were assessed with Dolphin Imaging software using CBCT data as predictor variables. Acoustic analysis of voice samples (vowel/a/) were performed with Praat software as outcome variables. The within-group and between-group differences in data were analyzed using paired-sample and independent-sample t tests. The degree of relationship between voice and CBCT parameters was assessed using Pearson correlation and multiple regression analysis. RESULTS: The study sample comprised 33 patients; 14 patients had class II skeletal deformity and 19 patients had class III skeletal deformity. Orthognathic surgery in both patients with class II and III skeletal deformities resulted in significant changes in all the voice parameters (All P < .05). Only patients with class II skeletal deformity showed significant changes in airway parameters (increase; all P < .001) and hyoid bone positions (anterosuperior movement; P = .001 and P = .008, respectively). Multiple regression analysis showed that some specific structural changes significantly affected some specific acoustic parameters. CONCLUSIONS: Bimaxillary orthognathic surgery significantly changed the acoustic parameters of voice in patients with class II and III skeletal deformities. Some of the structural changes were significantly associated with some of the acoustic parameters.

Effect of Botulinum Toxin Type A on Mandibular Fracture Healing: An Experimental Study in Rabbits.

PURPOSE: The effect of botulinum toxin type A (BTX-A) on fracture healing of the long bones is controversial, and no controlled clinical or experimental study has investigated the effect of BTX-A on mandibular fractures. The purpose of this study was to investigate whether BTX-A injection into the masseter muscles affects bone healing by reducing the displacing forces in an unfavorable mandibular fracture model. MATERIALS AND METHODS: Forty-eight male New Zealand white rabbits were used. Ten units of BTX-A was injected into each masseter muscle in the animals in the BTX-A group, whereas saline solution was injected in the animals in the control group. A unilateral osteotomy and fixation with a microplate were performed. Bone healing was evaluated by radiodensitometric, biomechanical, histologic, and histomorphometric methods after 21 days. RESULTS: The mean bone mineral density in the fracture area was significantly higher in the BTX-A group (P = .038). The mean failure load and bending modulus values were significantly higher in the BTX-A group than in the control group (P = .032 and P = .005, respectively). The mean histologic bone healing scores, bone volume-total volume values, and trabecular diameter values were significantly higher in the BTX-A group than in the control group (P = .001, P = .001, and P = .026, respectively). CONCLUSIONS: BTX-A application into the masseter muscles improves bone healing of a unilateral mandibular fracture in rabbits.

The Effects of Maxillary Expansion on Late Alveolar Bone Grafting in Patients With Unilateral Cleft Lip and Palate.

PURPOSE: The purpose of this study was to answer the research question of whether maxillary expansion provides enough postgraft stimulation to decrease the volume loss of alveolar bone grafts in patients with cleft lip and palate (CLP) who missed the appropriate treatment time. MATERIALS AND METHODS: This study was designed as a prospective controlled clinical trial. Thirty patients in the permanent-dentition stage with unilateral CLP were divided into 2 groups: In group I (mean age, 19.33 ± 5.16 years), slow maxillary expansion was performed before secondary alveolar bone grafting (SABG); in group II (mean age, 19.93 ± 3.99 years), slow maxillary expansion was performed 6 weeks after SABG. The iliac crest was preferred as a donor site for autogenous bone graft harvesting. Cone beam computed tomography images were taken 1 week, 6 months, and 12 months postoperatively. The volume and density of the alveolar bone graft were calculated using Mimics software (version 13.1; Materialise, Ann Arbor, MI), and SPSS software (version 19.0; IBM, Armonk, NY) was used for statistical analysis. RESULTS: The bone graft volume loss was significantly higher in group I than in group II after 6 months of healing (P = .003). The increase in bone density was significantly higher in group II than in group I after 6 months of healing (P = .017). Although the mean loss of volume was lower and the mean density of the bone graft was higher in group II, there was no significant difference between the 2 groups in terms of mean graft volume and mean bone density 12 months after the operation. For groups I and II, the mean bone graft volume loss was 46.3% and 34.6%, respectively, and the mean increase in bone density was 16% and 49%, respectively, after 12 months of healing. CONCLUSIONS: Maxillary expansion after late SABG may be taken into consideration as a treatment choice in selected unilateral CLP patients to provide bone graft stimulation.

Effects of hyperbaric oxygen treatment on implant osseointegration in experimental diabetes mellitus.

OBJECTIVE: To evaluate whether hyperbaric oxygen (HBO) treatment has a favorable effect on implant osseointegration in diabetic rabbits. MATERIAL AND METHODS: An experimental diabetes model was induced in 32 New Zealand rabbits through IV injection of alloxan. After the state of diabetes had been confirmed, one dental implant was placed in the metaphysical region of each animal's tibia. After the implants' placements, the animals were divided into two groups. Half of the animals underwent HBO treatment, while the other group did not receive HBO treatment and served as the control group. The animals were euthanized at the 4th and 8th weeks. The osseointegration of the implants were compared by histomorphometry and resonance frequency analysis (RFA). RESULTS: The Bone Implant Contact (BIC) values were significantly higher in the HBO group than in the control group at the 4th week. There was no difference in the BIC values between the groups at the 8th week. There was no significant difference in the RFA scores between the groups both at the 4th and 8th weeks after the operation. CONCLUSION: Histomorphometry findings suggest that HBO has positive effect on implant osseointegration in the early healing period in diabetic rabbits. However, implant stability is not affected by HBO treatment.

Reusing dental implants?: an experimental study for detecting the success rates of re-osseointegration.

BACKGROUND: The aim of this study was to histomorphometrically compare the implant-host integration between retrieved implants and new implants. METHODS: Jaws in 10 male beagle dogs were divided into four groups, and 36 dental implants were inserted into the jaws. In groups 1 and 2, experimental peri-implantitis was induced within 2 months after implant insertion. In group 1, surface decontamination of implants was achieved using air-flow and citric acid. In group 2, implants were sterilized with autoclave after air-flow and citric acid surface decontamination. Subsequently, these implants were inserted in contralateral jaws of the same dogs and a 3-month period was allowed for osseointegration. In group 3, the implants were removed from human jaws due to peri-implantitis and were inserted into dog jaws following surface cleaning protocol and sterilization with autoclave and a 3-month period was allowed for osseointegration. Group 4 was set as the control group. After the osseointegration period, all the animals were sacrificed. The degree of osseointegration in all groups was evaluated by evaluating the ISQ values and by using histomorphometric measurements. RESULTS: Histological findings showed that bone-implant contact (BIC) percentage (mean ± SD) was 83.39% ± 6.37 in group 1, 79.93% ± 11.83 in group 2, 75.45% ± 9.09 in group 3, and 80.53 ± 5.22 in group 4. Moreover, the resonance frequency analysis (RFA) and ISQ values were similar in all four groups both before and after the implantation. CONCLUSIONS: The results of this experimental study indicated that there is no significant difference between new dental implants and re-used dental implants with regards to osseointegration around the implant.

Effects of hyperbaric oxygen treatment on implant osseointegration in experimental diabetes mellitus

Abstract Objective To evaluate whether hyperbaric oxygen (HBO) treatment has a favorable effect on implant osseointegration in diabetic rabbits. Material and Methods An experimental diabetes model was induced in 32 New Zealand rabbits through IV injection of alloxan. After the state of diabetes had been confirmed, one dental implant was placed in the metaphysical region of each animal's tibia. After the implants' placements, the animals were divided into two groups. Half of the animals underwent HBO treatment, while the other group did not receive HBO treatment and served as the control group. The animals were euthanized at the 4th and 8th weeks. The osseointegration of the implants were compared by histomorphometry and resonance frequency analysis (RFA). Results The Bone Implant Contact (BIC) values were significantly higher in the HBO group than in the control group at the 4th week. There was no difference in the BIC values between the groups at the 8th week. There was no significant difference in the RFA scores between the groups both at the 4th and 8th weeks after the operation. Conclusion Histomorphometry findings suggest that HBO has positive effect on implant osseointegration in the early healing period in diabetic rabbits. However, implant stability is not affected by HBO treatment.

Effects of different loading protocols on the secondary stability and peri-implant bone density of the single implants in the posterior maxilla.

BACKGROUND: Immediate or early loading of dental implants becomes a clinically feasible concept. PURPOSE: The aim was to evaluate the effects of different loading protocols (immediate, early, and delayed) on secondary stability and peri-implant bone density of single implants in the posterior maxilla. MATERIALS AND METHODS: Thirty-nine implants (Dentium, South-Korea) were placed in 39 patients. After placement, implant stability values (ISQ) and baseline peri-implant bone density values derived from cone-beam computed tomography were recorded. Thirteen implants were included randomly in each loading groups. The secondary ISQ values were recorded during follow-up visits. Peri-implant bone density values were measured 1 year after placement again. Data was statistically analyzed. RESULTS: Immediate-loaded group showed the lowest ISQ values, 1 month after placement. During the next follow-up visits, delayed-loaded group showed the lowest ISQ values while other groups showed comparable results. Early loading increased the peri-implant bone density greater than the other groups. CONCLUSIONS: The peri-implant bone of early-loaded implants was significantly denser than that of immediate- and delayed-loaded implants, 1 year after placement. Density increment can be judged as the radiological findings of loaded-bone, which may also reduce the need for histomorphometric analysis of human biopsy to evaluate the bone reaction around the implants.

Effects of NSAIDs and hydroxyapatite coating on osseointegration.

PURPOSE: The aim of our study is to investigate the bone ongrowth of two different alternative surfaces and the effect of nonsteroidal anti-inflammatory drugs (NSAIDs) on osseointegration. METHODS: Hips of 40 New Zealand white rabbits were operated bilaterally. Hydroxyapatite (HA)-coated titanium rods were implanted into the right femur, and grit-blasted titanium rods were implanted into the left femur. They were divided into three groups. At the end of 8 weeks, both femora of the rabbits were removed and investigated biomechanically and histologically. RESULTS: HA-coated implants had a significantly better failure load and "percentage of bone-implant contact" than grit-blasted implants. There was no significant difference between the medication groups as a result of the biomechanical and histologic investigations. CONCLUSIONS: Our results indicate that NSAIDs did not have any negative effect on the osseointegration. HA-coated implants may provide more tensile strength and greater bone-implant contact rate in comparison with grit-blasted implants.

The effect of alendronate sodium on trabecular bone structure in an osteoporotic rat model.

OBJECTIVES: TObjectives: This study aims to investigate the effect of alendronate sodium on trabecular bone structure in an osteoporotic rat model. MATERIALS AND METHODS: Between May 2006 and July 2006, 60 female Wistar Albino rats aged three months were randomly allocated to three groups: sham operated receiving no treatment (Shm); ovariectomized-alendronate receiving 1 mg/kg/day alendronate sodium (Ovx-A), and ovariectomized-vehicle receiving 1 mL/kg/day physiological saline (Ovx-PS). Both Ovx groups received treatment through gastric gavage for 56 days. RESULTS: Densitometric measurements showed that bone mineral density decreased in the Ovx-PS and increased in Ovx-A groups (p<0.05). Biomechanical measurements showed a decrease in the breaking force in the Ovx-PS group and an increase in the Ovx-A group (p<0.05). Histomorphometric measurements showed that the Shm group had normal trabecular structure, while the Ovx-PS group had a less well- formed trabecular structure with a loss in the trabecular number and thickness and a corresponding increase in the trabecular spacing (p<0.05). In the Ovx-A group, there was an improvement in the trabecular structure with an increase in the trabecular number and thickness and a loss in the trabecular space (p<0.05). CONCLUSION: Our study results suggest that alendronate sodium is a valuable treatment agent for osteoporosis in postmenopausal women.

Histological Evaluation of the Effect of Concentrated Growth Factor on Bone Healing.

OBJECTIVES: The aim of this study was to evaluate the effects of concentrated growth factors (CGF) on the healing of peri-implant bone defects in an animal model. STUDY DESIGN: Twenty 4-month-old New Zealand White rabbits, each with an average weight of 3.5 kg, were used in this blinded, prospective, experimental study. Two implants were placed and 2 peri-impant defects were prepared in each rabbit tibia. Bone defects were created monocortically in the tibia of each rabbit using a trephine burr with a diameter of 8 mm. The implants were installed in each hole. The rabbits were divided into 4 groups: in group E, the defect was left empty; in group CGF, the defects were filled only with CGF; in group AB, the defects were filled with autogenous bone; and in group AB+CGF, the defects were filled with autogenous bone and CGF. The animals were euthanized at week 8 postimplantation. All implants from the 20 animals were fixed in 10% formalin and evaluated histomorphometrically. RESULTS: The mean defect area was highest in group E and lowest in group CGF+AB (P <0.05). The area of the defect differed significantly between groups AB and CGF+AB (P <0.05), but not between groups CGF and E. Implant-to-bone contact was lowest in group E. In the defect areas of groups CGF, AB and CGF+AB, a small amount of new bone formed around the implant. CONCLUSIONS: In this animal model of a peri-implant bone defect, restoration was achieved using a combination of autogenous bone and CGF. Further studies are needed to determine the behavior of CGF when used in the repair of bone defects in humans.

Histomorphometric Evaluation of Bone Formation in Peri-Implant Defects Treated With Different Regeneration Techniques: An Experimental Study in a Rabbit Model.

PURPOSE: The aim of this study was to investigate the healing of artificially created peri-implant circumferential bone defects using three bone-regeneration techniques. MATERIALS AND METHODS: Rabbit tibias (24 rabbits), in which bone defects (9-mm diameter, 4-mm depth) were created and implant beds (3-mm diameter, 6-mm depth) were prepared in the middle of the created defects, were used as the experimental model. Dental implants (3.0 × 10 mm) were inserted, and the peri-implant bone defects were grafted with demineralized freeze-dried bone allograft (DFDBA) plus saline solution, DFDBA plus platelet-rich fibrin (PRF), or DFDBA plus rifamycin. After 4 weeks, the animals were euthanized and the implants with surrounding bone were removed. Undecalcified histomorphometric examinations with toluidine blue staining were performed, and the bone-to-implant contact (BIC) and percentage of new bone formation were evaluated. RESULTS: The BIC was 50.94% ± 24.39% in the DFDBA-plus-saline solution group, 60.07% ± 4.91% in the DFDBA-plus-rifamycin group, and 73.43% ± 3.86% in the DFDBA-plus-PRF group. The percentage of new bone formation at the defect area was 37.61% ± 1.70% in the DFDBA-plus-saline solution group, 48.51% ± 2.80% in the DFDBA-plus-rifamycin group, and 63.09% ± 2.10% in the DFDBA-plus-PRF group. In terms of new bone formation and BIC, the DFDBA-plus-PRF and DFDBA-plus-rifamycin groups were significantly different from the DFDBA-plus-saline solution group. The difference between the DFDBA-plus-PRF and DFDBA-plus-rifamycin groups was also statistically significant. CONCLUSIONS: The addition of PRF or rifamycin to DFDBA had a significant positive effect on bone healing in peri-implant bone defects. The DFDBA-plus-PRF group showed the highest percentages of new bone formation and BIC.

Kinesio Taping for temporomandibular disorders: Single-blind, randomized, controlled trial of effectiveness.

BACKGROUND: Data regarding the effectiveness of Kinesio Taping in temporomandibular disorders (TMD) is scarce. OBJECTIVE: To determine the efficacy of Kinesio Taping (KT) in patients with TMD. METHODS: Patients with TMDs were randomized into experimental and control groups. The experimental group (n= 14) received KT in combination with counseling and jaw exercise, whilst controls (n= 14) were given the regimen of counseling and exercise alone. Jaw movements, Visual analogue scale (VAS) scores and self-reported measures (functional limitation and masticatory efficiency) were evaluated at baseline, first and sixth weeks of the treatment. Biobehavioral questionnaire was filled out at baseline and at sixth week. RESULTS: Active mouth opening improved more in the experimental group than controls (p= 0.003). In the experimental group, VAS for temporomandibular joint, masticatory efficiency and functional limitation improved significantly at the sixth week when compared to baseline (p= 0.011, p= 0.001 and p= 0.001, respectively), but not in controls. Subjective treatment efficacy was higher in the experimental group than that of controls (p= 0.000). Pain, depression and disability scores reduced significantly in the experimental group (p= 0.001, p= 0.006 and p= 0.01, respectively), but not in controls. CONCLUSION: In conclusion, KT in combination with counseling and exercise is more effective than counseling and exercise alone in TMDs.

Effects of bovine lactoferrin in surgically created bone defects on bone regeneration around implants.

The aim of this experimental study was to evaluate the effect of bovine lactoferrin (bLF)-loaded gelatin microspheres (GM) used in combination with anorganic bovine bone on bone regeneration in surgically created bone defects around tooth implants. Twenty-four uniform bone defects were created in the frontal bone via an extraoral approach in 12 domestic pigs. Twenty-four implants were placed at the center of the defects. In eight animals one of these defects was filled with 0.3 mL anorganic bovine bone while the other was left empty. In four animals, all defects were filled with 3 mg/defect bLF-loaded GM and anorganic bovine bone. All the defects were covered with collagen membranes. All animals were sacrificed after 10 weeks of healing, and the implants with the surrounding bone defects were removed en bloc. Undecalcified sections were prepared for histomorphometric analysis. The mean total area of hard tissue was 26.9 ± 6.0% in the empty defect group, 31.8 ± 8.4% in the graft group, and 47.6 ± 5.0% in the lactoferrin group (P < 0.001). The mean area of newly formed bone was 26.9 ± 6.0% in the empty defect group, 22.4 ± 8.2% in the graft group, and 46.1 ± 5.1% in the lactoferrin group (P < 0.001). The mean residual graft area was 9.4 ± 3.2% in the graft group and 1.5 ± 0.6% in the lactoferrin group (P < 0.001). The mean proportion of bone-implant contact in the defect region was 21.9 ± 8.4% in the empty defect group, 26.9 ± 10.1% in the graft group and 29.9 ± 10.3% in the lactoferrin group (P = 0.143). These data indicate that a combination of 3 mg bLF-loaded GM and bovine-derived HA promotes bone regeneration in defects around implants.

Histomorphometric evaluation of the effects of various diode lasers and force levels on orthodontic mini screw stability.

OBJECTIVE: The purpose of this study was to evaluate the effects of different laser dose and force levels on the stability of orthodontic mini screws used for anchorage, by histomorphometric analyses. BACKGROUND DATA: Low-level laser therapy speeds up blood flow, improves the mechanism of the revitalization processes, reduces the risk of infection, boosts metabolic activities, and accelerates the healing of the damaged tissue. Although there are many research studies about low-level laser therapy applications in a variety of areas, no investigations were found concerning mini screw stability using various laser dose levels with different force level applications. METHODS: Seventeen New Zealand white rabbits were used. A total of 68 cylindrical, self-drilling orthodontic mini screws were threaded at the fibula. Experimental subjects were divided into six groups; force application was not performed in the first three groups, whereas 150 g of force was applied via nickel-titanium closed-coil springs placed between two mini screws in the other three groups. Measurements of the initial torque values (10 Ncm) were manipulated by a digital portable torque gauge. Various low-level laser doses were applied to the groups during the postoperative 10 days. After 4 weeks, bone-to-implant contact and cortical bone thickness were histomorphometrically analyzed. RESULTS: In the 150 g force plus 20 J/cm(2) dosage group, the highest bone-to-implant contact values were observed. (p<0.05) There were no statistically significant correlations between cortical bone thickness and bone-to-implant contact values; on the other hand, no significant difference was found among the same groups in terms of cortical bone thickness values (p>0.05). CONCLUSIONS: Low-level laser therapy was noticed to induce the mini screw-bone contact area. Low-level laser therapy may be a supplementary treatment method to increase the stability of the orthodontic mini screw.

Osteointegration of a bisphenol-a-glycidyl-dimethacrylate composite and its use in anterior skull base defects: an experimental study in an experimental design model of cerebrospinal fluid leak.

OBJECT: Promising clinical results were reported in watertight closure of anterior skull base defects (ASBDs) with bisphenol-a-glycidyl-dimethacrylate (bis-GMA)-based materials to prevent the cerebrospinal fluid leaks. However, interrelation of these materials with surrounding bones in histologic level, referred to as the osteointegration, has not been reported in the anterior skull base. In addition, an illustrative case with an ASBD that was repaired using a bis-GMA composite has been presented. METHODS: Twenty New Zealand rabbits were divided into 4 groups: control and sham groups consisted of 2 and 6 rabbits, respectively. The "skull base defect" group (n = 6) underwent a unifrontal craniectomy and an iatrogenic ASBD followed by creating a dural defect to obtain a cerebrospinal fluid leak. Similar bony and dural defects were acquired in the "repair with bis-GMA based allograft" group (n = 6), but the bony defect was closed with bis-GMA-based allograft. RESULTS: All animals in the "skull base defect" group died in 3 weeks after surgery. There were no animal losses in the "repair with bis-GMA based allograft" group at the sixth month. Histologic evaluation revealed complete osteointegration of bis-GMA composite with surrounding bones. CONCLUSIONS: bis-GMA based allograft achieved a watertight repair of the ASBD. Histologic findings of this study showed that bis-GMA composite is a reliable material to be used in the closure of anterior skull base bony defects.

Does cone beam computed tomography-derived bone density give predictable data about stability changes of immediately loaded implants?: A 1-year resonance frequency follow-up study.

The aim of this clinical study was to evaluate whether preoperative bone density value derived from cone-beam computed tomography (CBCT) gives predictable data about primary and secondary stability characteristics of immediately loaded dental implants under different clinical variables. A total of 77 immediately loaded implants placed in 23 patients were included the study. Bone density values of the implant recipient sites were recorded using CBCT. The maximum insertion torque values (ITVs) of the implants were recorded using a digital torque meter during surgery. Resonance frequency measurements were taken using the Osstell Mentor at 4 time points; immediately after surgery (implant stability quotient [ISQ]0) and after 1 (ISQ1), 3 months (ISQ3), and 12 months (ISQ12) of loading. Data were analyzed statistically. The mean bone density and ITVs of all implants were 565 ± 81 and 36.8 ± 3.8 N · cm, respectively. The mean ISQ values were 73.6 ± 5.8 at baseline, 71.1 ± 6.5 after 1 month, 74.8 ± 5.6 after 3 months, and 76.6 ± 5.1 after 12 months of loading. Statistically significant differences were observed between ISQ0 and ISQ1 (P < 0.001), and ISQ0 and ISQ12 (P < 0.001), but not between ISQ0 and ISQ3 (P > 0.05). In regard to stability changes over time, statistically significant correlations were found between bone density values from CBCT and ISQ follow-up measurements, and between ITV and ISQ follow-up measurements in all examination periods. Thus, it is possible to predict primary and secondary stability characteristics of immediately loaded implants by using preoperative CBCT scan and perioperative ITV.

Effects of zoledronic acid on physiologic bone remodeling of condylar part of TMJ: a radiologic and histomorphometric examination in rabbits.

OBJECTIVE: The purpose of the present study is to evaluate the effects of systemically administered zoledronic acid (ZA) on the physiological bone remodeling and the microarchitectural parameters of the condylar part of TMJ in a rabbit model. STUDY DESIGN: Thirty skeletally mature male New Zealand white rabbits were randomly divided into two groups. The experimental group was administered an intravenous, single dose of 0.1 mg/kg ZA diluted with 15 mL of saline in a 15-minute perfusion with an infusion pump. The control group was administered only saline infusion for 15 minutes. All rabbits were sacrificed on the 21st postoperative day. Radiodensitometric and histomorphometric examinations were performed on the harvested mandibular condyles. The data were analyzed statistically. RESULTS: Radiodensitometric findings showed that ZA treatment resulted in a significant increase in the mineralization of mandibular condyle. This result was supported by the histomorphometric findings. CONCLUSION: The present study has revealed that a temporary delay in the physiological bone remodeling using single dose of ZA increases bone mineral content and makes the microarchitecture of the mandibular condyle more compact. These effects may be regarded as base data and considered in numerous clinical situations including TMJ.

Evaluation of relationship between preoperative bone density values derived from cone beam computed tomography and implant stability parameters: a clinical study.

OBJECTIVES: The aim of this study was to explore the efficacy of bone density value derived from cone beam computed tomography (CBCT) by evaluating its correlation with implant stability parameters including insertion torque value (ITV) and radiofrequency analysis in relation to different clinical variables including location, gender, age, bone quality, and implant diameter. MATERIAL AND METHODS: A total of 65 implants were placed in 17 patients. The bone densities of implant recipient sites were preoperatively recorded using CBCT. Bone quality was subjectively assessed, which depends on the stiffness of the jawbone according to the Lekholm and Zarb index during drilling procedure. The maximum ITV of each implant was recorded using a digital torque meter during implant placement. Resonance frequency measurements were taken using an Osstell Mentor immediately after implant placement. Data were analyzed statistically. RESULTS: The mean bone density, insertion torque, and implant stability quotient values of all implants were 556 ± 80, 37.4 ± 3.3 Ncm, and 73.8 ± 7.2, respectively. Statistically significant correlations were found between bone density values from CBCT and implant stability parameters in relation to all variables. CONCLUSION: Bone density assessment using CBCT is an efficient method and significantly correlated with implant stability parameters and Lekholm and Zarb index. Thus, it is possible to predict initial implant stability and possibility of immediate or early loading using CBCT scans prior to implant placement.