Early loading of surface modified implants in the posterior mandible - 5 year results of an open prospective non-controlled study.

AIM: The aim of the present study was to evaluate an early loading protocol for surface modified implants placed in the posterior mandible. MATERIAL AND METHODS: A total of 134 implants with a TiO(2) blasted, fluoride modified surface were inserted into the posterior mandibles of 44 patients. The implants were functionally loaded after 7 weeks of healing. Implant stability quotient (ISQ) values (during the first year), bleeding on probing (BOP), plaque accumulation and marginal bone level (MBL) were assessed until the end of the observation period of 5 years. A total of 41 patients with 123 implants completed the study. RESULTS: No implants were lost. ISQ values decreased significantly from the time of insertion to 2 weeks and increased significantly until the 1-year follow up. BOP varied until the end of the observation period between 7.9% and 13.0%. Plaque accumulation decreased from the time of early loading to the end of the study. MBL changed from 0.59 mm at the time of implant placement to 0.80 mm at the time of early loading. Thereafter, only slight variations in MBL occurred until the end of the observation period. CONCLUSIONS: The results confirm that early loading is a promising option also in posterior edentulism of the mandible.

Distribution of anthocyanins delivered from a bioadhesive black raspberry gel following topical intraoral application in normal healthy volunteers.

PURPOSE: Results from our oral cavity chemoprevention trial demonstrated appreciable interpatient variations regarding chemopreventive efficacy of a freeze dried black raspberry (FBR) gel. We speculated these data reflected individual patient-related differences in absorption, target tissue uptake and local compound metabolism of key FBR compounds (anthocyanins). Accordingly, this study assessed the distribution of anthocyanins from the 10% (w/w) FBR gel in saliva, oral tissues and plasma. METHODS: Human subject participation entailed collection of: (1) saliva, tissue and plasma (5 min following gel application, keratinized tissues), (2) saliva and plasma (5 min after sublingual gel application), (3) saliva and plasma at 1, 2, and 4 h post gel application (keratinized tissues), and (4) saliva (cyanidin 3-rutinoside incubations). Levels of FBR anthocyanins in the respective samples were analyzed by LC/MS/MS. RESULTS: Our data show: significantly higher anthocyanin levels in saliva and oral tissues relative to matched plasma samples, marked donor-specific variations in anthocyanin uptake, sustainability of anthocyanins at the target site, pH affects anthocyanin penetration and intraoral anthocyanin decomposition and/or metabolism. CONCLUSIONS: No previous oral cavity chemoprevention trials evaluated compound distribution at the treatment site. Our data, which demonstrate a local delivery-derived pharmacologic advantage, provide insights which could advance oral cavity chemoprevention strategies.

Case report: autotransplantation for a missing permanent maxillary incisor.

Patients with nonrestorable or missing anterior teeth are typically seen by their general or pediatric dentist who directs the course of consultation, referral, and treatment. In the mixed dentition stage, loss of permanent maxillary incisors is usually treated by various forms of removable/fixed prosthetic appliances. Because premolars are developing during this time period, transplantation of an available premolar to an incisor position is a viable alternative, that may provide a better biological substitute for a missing incisor than other choices. The purpose of this case report was to describe the treatment of the loss of a permanent maxillary central incisor by transplantation of a maxillary first premolar to the incisor position. Autotransplantation allowed normal alveolar bone development and a future option of permanent restoration without implants or partial dentures. Autotransplantation should be given consideration as a reasonable option for the treatment of missing incisors in mixed dentition.

Genetic disorders and bone affecting the craniofacial skeleton.

Genetic disorders of bone constitute a large number of alterations approaching almost 300 types. This article focuses on the most common disorders in this group, which at the same time are the most clinically significant because of their incidence and degree of involvement of the craniofacial skeleton.

Effect of alendronate on endosseous implant integration: an in vivo study in rabbits.

PURPOSE: Alendronate sodium (Fosamax; Merck, Whitehouse Station, NJ) is a second-generation bisphosphonate used widely in osteopenic individuals for decreasing bone resorption and increasing bone density. The ability of alendronate to affect systemic bone remodeling raises natural questions about the drug's influence on dental implant osseointegration. Current knowledge regarding the effect of systemic bisphosphonates, specifically alendronate, on all 3 phrases of osseointegration is incomplete and only a few studies have started to investigate peri-implant bone responses to alendronate-coated implants. The purpose of this study was to determine the effect of systemic alendronate therapy on osseointegration of dental implants based on torque-removal values in rabbits. MATERIALS AND METHODS: Identical titanium dental implants were placed using a standardized surgical protocol in the bilateral distal femur and proximal tibia of 20 New Zealand white rabbits (79 implants total). One week before implant placement, 10 rabbits were given doses of alendronate and continued on weekly dosing for 5 weeks until euthanized. The other 10 rabbits were untreated controls. Torque-removal values were determined using a Tohinichi 15-BTG torque wrench (Tohinichi Mfg Co, Ltd, Tokyo, Japan) for all implants. RESULTS: Analysis of torque data showed no statistical differences between the alendronate and control groups in both femur and tibia sites. A statistically significant difference, however, was noted in torque removal values between femur and tibia sites regardless of drug or non-drug groups. CONCLUSIONS: In summary, orally dosed alendronate administration in rabbits had no significant effect on dental implant torque-removal values 6 weeks after endosseous placement in femur and tibia.

Heat production by 3 implant drill systems after repeated drilling and sterilization.

PURPOSE: The goal was to measure heat generated in bone by 3 implant drill systems after repeated drilling and sterilization. MATERIALS AND METHODS: Temperature was measured with thermocouple technology in vitro using the bovine femoral cortical bone model. Intermittent drilling was accomplished at a constant 2.4-kg load and drill speed of 2,500 rpm. External irrigation at 40 mL/min with normal saline was used. Three implant drill systems-system A (triple twist drills with a relief angle), system B (triple twist drills without a relief angle), and system C (double twist drills with a relief angle)-were evaluated and heat was measured at the final drill in the drilling sequence (4.0 mm or 4.2 mm) at a depth of 15 mm. Thermocouples were placed 0.5 mm from the osteotomy at a depth of 15 mm. Heat measurements were recorded out to 25 uses. RESULTS: Results showed temperature increased with multiple uses. System A and C drills had temperature measurements that were below 47 degrees C, even after 25 uses. System B drills had temperatures that exceeded 47 degrees C from the initial use. Light microscopy showed little drill wear even after 25 uses. CONCLUSIONS: Drill geometry plays a major role in heat production and may explain the increased temperature readings seen in system B. These drills lack relief angles and have the smallest clearance angles of the 3 systems. It also has fewer drills in its drilling sequence compared with systems A and C. This study shows that temperatures increase when drills are used multiple times. Systems A and C had acceptable temperature measurements out to 25 uses. System B drills showed significantly higher heat production with little visual signs of wear.

Perioperative management of the patient with hematologic disorders.

Bleeding at the time of surgery has the potential to become a serious complication. Careful patient assessment and review of history are of the utmost importance if this situation is to be avoided on the operating table. Unfortunately, many patients, particularly younger individuals with little to no previous exposure to surgery, are unaware of underlying bleeding disorders that they may have. Understanding the basic pathophysiology and management of these conditions becomes critical for the treating surgeon. For patients who have known conditions, close interconsultation with the treating hematologists and careful observation of preoperative, intraoperative, and postoperative established protocols reduces the risk of complications for patients and makes the possibility of success a reality for these individuals.

Comparison of strains produced by titanium and poly D, L-lactide Acid plating systems to in vitro forces.

PURPOSE: To determine if a specific resorbable plating system provides similar fixation, in terms of strain distribution under load, to a titanium system when the Champy technique is applied for the treatment of a mandibular angle fracture. MATERIALS AND METHODS: A formalin-fixed cadaver mandible was harvested just before the study. A bicortical osteotomy was then made using a diamond disc extending in an oblique direction in the area of the angle. It was then passively fixated with a 4-hole 2.0-mm miniplate. Two stacked rosette strain gauges were bonded to the mandible on either side of the fracture. Each rosette had 3 strain gauges arranged in specific degrees relative to each other. The mandible was then placed on a dynanometer and 30 lb loads were delivered on the ipsilateral molar. Static resistance was placed in the condylar neck region to simulate the glenoid fossa. Loading was repeated 10 times with a period of 3 minutes between loads. Measurements were recorded for each strain gauge after loads were in place for 30 seconds. The same process was repeated using a 4-hole 2.1-mm resorbable miniplate. The strains were then used to calculate the maximum and minimum strains for each rosette. Hooke's law was used to calculate the principal stresses. RESULTS: Differences were observed between the strain gauges for each individual plating system. There was variability within the resorbable plate measurements as shown by the standard deviation. Using the REML ANOVA test, a significant difference was found between the 2 materials. CONCLUSION: In this in vitro study, there were significant biomechanical differences observed between a 2.0-mm titanium miniplate and a 2.1-mm resorbable miniplate when used to treat a mandibular angle fracture following Champy's principles. Based on our finding, both systems cannot be used interchangeably for the treatment of mandibular angle fractures under the same clinical conditions.

Palatal perforation associated with intranasal prescription narcotic abuse.

BACKGROUND: Palatal perforation resulting from insufflation of cocaine has been well documented. In comparison, reports of destructive orofacial lesions resulting from intranasal abuse of prescription narcotics are rare. We present the clinical and histologic findings in a case of palatal perforation arising in a patient abusing a prescription opioid drug. The patient denied any history of cocaine use but admitted to habitually crushing and snorting a hydrocodone/acetaminophen preparation. Study design The patient presented to our clinic seeking resolution of speech difficulties associated with an oroantral fistula. Surgical repair of the defect had been attempted unsuccessfully in the past. In addition to blood and chemistry panels, endoscopic examination was conducted, with removal of several biopsy specimens for histologic evaluation and flow cytometry. Biopsy specimens included both lesional and perilesional tissue from within the oral and nasopharyngeal cavities. Culture and cytology for fungal organisms were also performed. RESULTS: Histopathologic examination revealed normal mucosa with diffuse and focal inflammatory changes and no evidence of malignancy. Polarizable foreign material was noted in the specimens. The absence of lymphoid neoplasia was confirmed by flow cytometric analysis. The toxicology panel was positive for the presence of opiates in the blood. Culture and cytology were positive for candidal organisms. A palatal obturator was fabricated for the patient, producing significant improvement in the quality of speech. CONCLUSIONS: This may represent a case of palatal perforation resulting from abuse of a drug other than cocaine. The potential for drugs other than cocaine to produce destructive orofacial lesions should be considered.

Immunohistochemical assessment of Viadent-associated leukoplakia.

Studies show an association between sanguinarine, the active ingredient in Viadent oral health care products, and oral premalignant lesions. The study was undertaken to quantitatively compare the staining profiles of sanguinarine-associated leukoplakia to normal and dysplastic specimens. Archived oral mucosal specimens were stained for tumor markers p16, p53, cyclin D1, Ki-67, and Bcl-x and analyzed through Simple PCI image analysis software. Quantitative analyses showed trends towards intermediate staining in Viadent-related specimens (Ki-67: normal: 18.12+/-2.15, Viadent: 16.12+/-2.16, dysplasia: 14.53+/-2.04, p>0.05; cyclin D1: normal: 15.65+/-3.68, Viadent: 12.52+/-3.57, dysplasia: 1.94+/-3.93, p<0.05; p16: normal: 55.04+/-4.16, Viadent: 49.74+/-4.16, dysplasia: 45.03+/-4.45; p>0.05; p53:normal: 2.65+/-1.37, Viadent: 4.64+/-1.52, dysplasia: 8.71+/-1.37; p<0.05 Kruskal Wallace, Tukey/Kramer). Our Viadent profiles, intermediate between normal and dysplasia, support a preneoplastic nature of this process.

Using resorbable screws for fixation of cortical onlay bone grafts: an in vivo study in rabbits.

PURPOSE: The purpose of this study is to test bioresorbable screws as an alternative to titanium screw graft fixation. When cortical onlay grafts are used, it is necessary to rigidly immobilize them with titanium screws into the recipient site. The screws must be removed before placing implants into this site. Bioresorbable screws may be an alternative to titanium fixation, eliminating the additional morbidity associated with this. MATERIALS AND METHODS: Fifteen New Zealand White rabbits were divided into 3 groups. Bilateral tibial onlay bone grafts were placed in the mandible and secured using titanium fixation, bioresorbable fixation, or no fixation. After 6 weeks, all grafted sites were harvested. Hematoxylin-eosin and Giemsa staining were performed to evaluate inflammation, graft integration, and thickness. RESULTS: The treatment groups showed evidence of consolidation under light microscopy. Smooth integration of the graft borders with the recipient bone was identified. No integration was seen in the control group. The average thickness of the grafted sites was: 1) bioresorbable, 2.28 mm; 2) titanium, 1.87 mm; and 3) control, 1.06 mm. The differences were statistically significant (P = .0004) between the titanium group and the control group, as well as between the bioresorbable and the control group (P = .01). There was no statistically significant difference between the 2 treatment groups (P = .19). CONCLUSION: The overall thickness of the treatment specimens was greater than that of the control group. The bioresorbable group showed graft integration equal to that of the titanium group, making it an adequate alternative for graft fixation.

A comparative study of 2 imaging techniques for the diagnosis of condylar fractures in children.

PURPOSE: We sought to compare the sensitivity and specificity of panoramic radiographs with those of coronal computed tomography (CT) scans in the diagnosis of mandibular condylar fractures in the pediatric population. METHODS: Medical, dental, and radiographic records of patients who presented between 1995 and 2000 were evaluated for injuries involving the mandibular condyle. The sample included 22 males and 15 females with ages ranging from 2 to 15 years (mean, 8 years). Control subjects were added and matched by age and gender. The panoramic radiographs were blocked to allow separate evaluation of each condyle. Representative images from the CT scans were selected and individually photographed for projection. Both sets of images were evaluated by 4 groups of examiners: oral and maxillofacial (OMF) surgeons who regularly deal with pediatric trauma (n = 2), community OMF surgeons who had been out of training for at least 5 years (n = 6), OMF radiologists (n = 3), and OMF surgery residents (n = 6). Each image was shown for 20 seconds and the examiners were given 3 options to choose: 1) fracture, 2) no fracture, and 3) uncertain. RESULTS: The overall diagnostic accuracy of CT scanning was 90% (sensitivity, 92%; specificity, 87%), and that of panoramic radiographs was 73% (sensitivity, 70%; specificity, 77%). Of interest, the most experienced clinicians were also those most likely to respond that panoramic films were not diagnostic. Statistical analysis of the results was performed using chi(2) analysis. The differences for sensitivity measurements using the CT scan were not statistically significant (P >.1). However, the differences in sensitivity measurements using the panoramic radiographs and the specificity measurements using both the CT and panoramic radiographs were statistically significant (P <.05). CONCLUSIONS: CT scans provide consistently greater accuracy of diagnosis, sensitivity, and specificity than panoramic radiographs in the assessment of children suspected of having condylar fractures. In view of the high rate of false-negative and false-positive results associated with panoramic radiographs, coronal CT scans should be considered routine investigation in these patients.