Periapical foreign body findings - histological and radiological comparison.

OBJECTIVE: This study aimed to clarify the perceptibility of periapical foreign materials in imaging compared with histopathology. We hypothesized that dentoalveolar imaging is sufficient to detect periapical foreign bodies. MATERIAL AND METHODS: Radiological and histopathological records of patients diagnosed with periapical granuloma or radicular cyst from 2000 to 2013 were evaluated retrospectively. Patients with histologically verified foreign bodies were included in the study and their pathological samples and radiological images were reviewed. The outcome variable was radiologically detectable foreign material. The predictor variables were histopathological diagnosis, type of inflammation, type and number of foreign bodies, imaging modality, and site of foreign material. RESULTS: Compared to the histopathological diagnosis of foreign bodies as the gold standard, the level of radiologic detectability was mild. Histologically verified foreign material could be detected by imaging in 32/59 (53.5%) patients. Histological diagnosis, type of inflammation, type or number of foreign bodies, imaging modality or site of foreign material had no association with radiological detectability (p > 0.05). CONCLUSIONS: According to our results, histopathology is a more accurate diagnostic tool than radiology in periapical foreign bodies or foreign body reactions. Clinicians should keep in mind the limitations of imaging when setting the diagnosis and planning treatment.

MRI correlates to histopathological data in oral tongue squamous cell carcinoma diagnostics.

OBJECTIVES: The purpose of this study was to compare magnetic resonance imaging (MRI) maximum tumor diameter and depth of invasion with histopathology in oral tongue squamous cell carcinoma (OTSCC) patients in our Institute. Another objective was to compare recorded nodal status between MRI and histology. MATERIAL AND METHODS: MRI and pathological records of 45 patients diagnosed with T1-T3 OTSCC were reviewed retrospectively. Maximum tumor diameter and depth of invasion were measured and rechecked by oral radiologist and pathologist. Nodal status was recorded from both MRI and histopathology. Correlation analyses were performed using Pearson's correlation. RESULTS: Both maximum tumor diameter and depth of invasion correlated significantly between MRI and histology (ρ = 0.874, p < .001; ρ = 0.898, p < .001). Significant correlation was found between MRI and pathological dimensions in the MRI-based T-staged subgroups of T2 and T3 but not in T1. MRI sensitivity for detecting pathologically positive nodes was 60%. MRI specificity for detecting pathologically negative nodes was 83%. Moderate correlation was found between MRI and histological nodal status (ρ = 0.44, p = .003). CONCLUSIONS: MRI tumor dimensions correlate with histopathological data in OTSCC. Based on our Finnish patient material and results, MRI serves as an accurate tool in supporting OTSCC patient treatment in our Institute.

Ameloblastoma: a retrospective single institute study of 34 subjects.

Objective: This study aims to clarify demographic and clinical aspects of patients with ameloblastoma treated at a single Finnish institute during 1985-2016. Associations between predictor variables (gender and age) and outcome variables (location, tumour type, growth patterns and average tumour size) were sought.Materials and methods: A retrospective cohort study was designed and implemented including 34 patients diagnosed with primary ameloblastoma and treated at the Helsinki University Central Hospital. Patient records were investigated, and tissue samples re-evaluated. The chi-square test was used on all categorized variables and t-test for continuous ones. A p value equal to or under .05 was considered significant.Results: Males were slightly more predominant among the Finnish patients with ameloblastoma. Maxillary tumours were seen exclusively in male patients (p = .034). Additionally, these patients were older than patients with mandibular tumours (p = .007). A mixture in histological growth patterns was more common than originally anticipated. The study revealed a wide range of clinical signs and subjective symptoms, of which pain or other sensations were experienced most often.Conclusions: This study of 34 subjects shows that southern Finnish patients with ameloblastoma do not substantially differ from patients in similar study designs.

Associated Injuries Are Frequent and Severe Among Geriatric Patients With Zygomatico-Orbital Fractures.

PURPOSE: Associated injuries (AIs) are hypothesized to be frequent in geriatric zygomatico-orbital (ZMO) fractures. The study aim was to determine the relation between ZMO fractures and AIs in geriatric patients compared with younger adult patients. PATIENTS AND METHODS: A retrospective case-and-control study was carried out on geriatric patients at least 65 years of age (n = 93) and younger adult patients 20 to 30 years of age (n = 68) diagnosed with pure unilateral ZMO fractures. The main exposure was age, the primary outcome was AI outside the face, and the secondary outcomes were type and severity of AI, ocular injuries, restriction of mandibular movement, and ZMO buttress asymmetry. The confounding variables were gender, trauma mechanism, type of ZMO fracture, and dislocation. Statistical analyses included χ2 tests, risk evaluation with 2 × 2 tables, and logistic regression analysis. RESULTS: AIs outside the face, and particularly brain injuries, were significantly more frequent in the geriatric group than in the control group (P < .001). The significant predictors of AIs outside the face were fall from a height (66.7%), motor vehicle accidents (66.7%), and absence of ZMO dislocation (59.5%; P < .001). The adjusted risk of brain injury was 2.5-fold in the absence of dislocation. The geriatric group had a more than 5-fold higher risk of brain injuries compared with the younger control group (P = .003). CONCLUSIONS: AIs in general, and particularly brain injuries, are frequent in geriatric ZMO fractures. Intracranial injuries should be ruled out, particularly in geriatric patients diagnosed with a non-dislocated ZMO fracture.

Isolated Orbital Fractures Are Severe Among Geriatric Patients.

PURPOSE: The purpose of the present study was to clarify the reasons for, types of, and degree of involvement of the orbital wall and the severity of orbital fractures in geriatric patients and to compare the differences between geriatric and younger adult patients. MATERIALS AND METHODS: A retrospective case-control study of geriatric patients aged at least 65 years (n = 72) and younger controls aged 20 to 50 years (n = 58) with a diagnosis of a unilateral isolated orbital fracture was designed and implemented. The main exposure was age, the primary outcome was the isolated orbital fracture type, and the secondary outcomes were the associated orbital zones, fracture area (cm2), degree of dislocation (mm), involvement of anatomic landmarks, diplopia, altered ocular position, restricted eye movement, and ocular injuries. The confounding variables were gender, trauma mechanism, and alcohol abuse. The statistical methods included χ2 tests and logistic regression analyses. RESULTS: Among the geriatric patients, the great majority of isolated orbital fractures had been caused by falls (66.7%; P < .001). Geriatric orbital fractures were significantly more often extensive (2 cm2 or larger; P = .045) and associated with the middle-posterior orbital third (P = .032). In the logistic regression analyses, the elderly had a 2.2-fold greater risk of fractures of the middle-posterior orbital third and a 2.3-fold greater risk of extensive fractures compared with the younger controls. Ocular injuries were only diagnosed in the geriatric patients (5.6%). CONCLUSIONS: Falling is the most common mechanism of elderly orbital fractures. Isolated orbital fractures are extensive and mainly affect the globe supporting the middle and posterior parts of the orbital floor among geriatric patients.

Osteotomy Site Grafting in Bilateral Sagittal Split Surgery With Bioactive Glass S53P4 for Skeletal Stability.

In orthognathic surgery, the aim of the treatment is to achieve a good occlusion and a satisfying aesthetic outcome. In large mandibular advancements insufficient healing at the mandibular inferior border may lead to loss of support for the overlaying tissue at the osteotomy site. Augmentation can be performed to improve stability, bone regeneration, and the aesthetic outcome. The purpose of this prospective clinical study was to evaluate the use of a novel material for this indication; granules of the antibacterial, osteoconductive, and slowly resorbing bioactive glass S53P4 as filling material in large mandibular advancement in bilateral sagittal split osteotomies. The authors treated 25 patients who underwent bilateral sagittal split osteotomies due to class II dentoskeletal deformities. The mandibular osteotomy site defects (8-15 mm) were augmented with bioactive glass S53P4. The average clinical follow-up was 33 months and the average radiological follow-up with cone beam computerized tomography was 24 months. The clinical and radiological results were good with regard to healing, bone regeneration, and stability of the osteotomy sites. The recontouring of the inferior mandibular border provided a good soft tissue support followed by an excellent aesthetic outcome in 96% of the osteotomy sites. The occlusion was stable in 88% of the patients. The authors' results show that bioactive glass S53P4 is a safe grafting material for osteotomy site defects in significant mandibular advancements with reliable bone regeneration, providing long-term stability at the osteotomy site and at the inferior mandibular border.

Does Dexamethasone Facilitate Neurosensory Function Regeneration After Zygomatic Fracture? A Randomized Controlled Trial.

PURPOSE: This study sought to clarify the rate of neurosensory disturbance (NSD) after zygomatic complex fractures in general, as well as the effect of perioperatively administered dexamethasone on neurosensory recovery. PATIENTS AND METHODS: This was a single-blinded randomized study aiming to clarify the benefits of perioperative dexamethasone after surgery. The patients were randomly assigned either to receive dexamethasone (up to a total dose of 10 or 30 mg) or to act as control patients (no glucocorticoid treatment). The outcome variable was NSD, the presence of which was established when patients had any sensory disturbance of the infraorbital nerve. Other predictor variables included in the analysis were age, gender, time span from accident to surgery, surgical approach to the fracture line, and relation of the fracture to the infraorbital foramen. The statistical significance of associations was evaluated with χ2 tests. RESULTS: We included 64 patients in the analyses. Of the patients in the dexamethasone group (either 10 or 30 mg), 58.3% had NSD at 6 months postoperatively, whereas in the control group, 66.7% of the patients had NSD. This finding was not statistically significant (P = .565). At the 1-month interval, the patients without a fracture through the infraorbital foramen had less NSD (P = .009); this finding was not significant at 3 and 6 months postoperatively. Age, gender, injury mechanism, surgical approach, and time span from accident to surgery were not significant predictors of NSD. In total, 64.4% of the patients still had NSD at 6 months postoperatively. CONCLUSIONS: This study showed no benefits of short-term, high-dose dexamethasone administration in the neurosensory recovery of patients with zygomatic complex fractures. The type of primary trauma is the main cause of NSD, but the precise predictors remain unknown.

Early stage minor salivary gland adenoid cystic carcinoma has favourable prognosis.

The purpose of the study was to evaluate the long-term outcome of minor salivary and mucous gland (MiSG) adenoid cystic carcinoma (ACC) of the head and neck and to compare the results with earlier reports including our recently published series on major salivary gland (MaSG) ACC. The study comprised 68 MiSG ACCs operated during 1974-2012 at the Helsinki University Hospital, Helsinki, Finland. Medical records and histological samples were reviewed. Our previously published cohort comprising 54 MaSG ACCs during the years from 1974 to 2009 was used for comparison. The most common locations were the oral cavity and sinonasal cavities. Most patients presented stages IV (33.8%) and I (23.5%) disease. Primary treatment with curative intent, mainly surgery, was offered for 64 patients. Thirty-three (51.6%) of these patients developed a disease recurrence and 22 (66.7%) patients in less than 5 years. The difference in the length of recurrence-free time (<5 vs. >5 years) had an impact on OS and DSS (p < 0.001) showing worse prognosis for the earlier recurring group. T classes 2-4 (p = 0.005, p < 0.001, and p = 0.001, respectively) and stages II-IV (p = 0.019, p < 0.001, and p = 0.002, respectively) were associated with worse OS, DSS, and DFS. MiSG ACC had a similar long-term survival compared to MaSG ACC. Patients with stage I MiSG ACC seem to carry a favourable prognosis compared with those with stages II, III, and IV tumours. It is thus noteworthy that stage II tumours represent a truly advanced disease entity warranting a more aggressive treatment approach.

Regeneration of Cystic Bone Cavities and Bone Defects With Bioactive Glass S53P4 in the Upper and Lower Jaws.

Cysts and tumors are common lesions in the jaws. To be able to retain a good volume of the alveolar ridge during healing as well as strengthening the angle and body of the mandible and provide an instant improved support for adjacent teeth, reliable long-term bone regeneration is needed. The purpose of this prospective study was to promote bone regeneration by filling bony defects in the upper or lower jaw with granules of the bioactive glass S53P4 (BAG), which have osteostimulative and antimicrobial properties.The authors treated 20 patients (21 defects) surgically; benign tumors, cysts, or infection related to impacted teeth in the maxilla or mandible. The tumor or cyst was removed or enucleated and thorough cleaning of the infected area was performed. The bone cavity was filled with granules of the BAG S53P4 despite signs of chronic infection in the area at the time of surgery. The patients were followed up for an average of 34 months clinically and with cone beam computerized tomography for 28 months. In 20 defects the final outcome was successful. Despite infection at the time of surgery in 65% of the patients, no material associated infection was seen during the follow-up. The BAG S53P4 granules were radiologically remodeled into bone after 2 years follow-up. The use of granules of the BAG S53P4 in the treatment of large bone defects provides infection-free reliable bone regeneration despite chronic infection at the time of surgery, which improves the prognosis of adjacent teeth.

A Comparison of Bone Resorption Over Time: An Analysis of the Free Scapular, Iliac Crest, and Fibular Microvascular Flaps in Mandibular Reconstruction.

PURPOSE: The aim of the present study was to compare the resorption of the bone in the free scapular, free iliac crest, and free fibular microvascular flaps in mandibular reconstruction over time. PATIENTS AND METHODS: In the present retrospective study, we analyzed 186 consecutive patients with scapular, fibular, or deep circumflex iliac artery (DCIA) osseous free microvascular flaps in mandibular reconstruction. We followed up the patients clinically and using multislice computed tomography (MSCT) with volume analyses of the bone. The volume of the bone was analyzed against time. RESULTS: A total of 38 patients fulfilled the study criteria. Resorption of the osseous flaps was found to continue for several years. At 2 years, the volume loss was 14% for the scapula, 3% for the DCIA, and 1% for the fibula. Three-dimensional (3D) volume analysis of the MSCT scans showed more resorption than 2-dimensional analyses of the radiographs. Postoperative radiation therapy, patient age, and patient gender did not correlate with bone resorption. CONCLUSIONS: After microvascular mandibular reconstruction, the volume reduction over time is the least in the fibula and the greatest in scapula, with that of the DCIA in between. The volume reduction continues for several years in all of these. For assessment of the volume reduction of osseal reconstruction, a 3D volume analysis is more reliable than height by width measurements.

Malpractice claims related to tooth extractions.

OBJECTIVE: The aim of this study was to analyze malpractice claims related to tooth extractions in order to identify areas requiring emphasis and eventually to reduce the number of complications. MATERIAL AND METHODS: We compiled a file of all malpractice claims related to tooth extractions (EBA code) between 1997 and 2010 from the Finnish Patient Insurance Centre. We then examined the data with respect to date, tooth, surgery, injury diagnosis, and the authority's decision on the case. RESULTS: The material consisted of 852 completed patient cases. Most of the teeth were third molars (66 %), followed by first molars (8 %), and second molars (7 %). The majority of claims were related to operative extraction (71 %) followed by ordinary extraction (17 %) and apicoectomy of a single-rooted tooth (7 %) or multi-rooted tooth (2 %). The most common diagnosis was injury of the lingual or inferior alveolar nerve. According to the authority's decision, the patient received compensation more often in cases involving a third molar than other teeth (56 vs. 46 %, P < 0.05). CONCLUSION: The removal of a mandibular third molar was the basis for the majority of malpractice claims. CLINICAL RELEVANCE: To reduce the numbers of lingual and inferior alveolar nerve injuries, the removal of mandibular third molars necessitates recent and high-quality panoramic radiograph, preoperative assessment of the difficulty of removal, and consciousness of the variable anatomical course of the lingual nerve.

Influence of perioperative dexamethasone on delayed union in mandibular fractures: A clinical and radiological study.

BACKGROUND: The aim was to clarify the occurrence of delayed union after surgical treatment of mandibular fracture and investigate whether an association exists between perioperative use of dexamethasone and delayed union. MATERIAL AND METHODS: Thirty-seven patients were included in a prospective randomized study. Of these patients, 19 (51.4%) were randomized to receive a total dose of 30 mg of dexamethasone and 18 (48.6%) served as controls. Patients underwent clinical and radiological investigation immediately, one month, three months and six months postoperatively. Radiographs were evaluated by an experienced, blinded senior oral radiologist. RESULTS: Delayed fracture union was found in 9 patients (24.3%). It was associated significantly with angle fractures (p=0.012). Delayed union occurred more frequently in patients who received dexamethasone (36.8%) than in those who did not (11.1%) (p=0.068). The association of infection with delayed union was significant (p=0.027). Moreover, dexamethasone was significantly (p=0.019) associated with delayed fracture union with concomitant infection. Gender, age group, smoking habit, treatment delay and duration of surgery were not associated with delayed union. CONCLUSIONS: Infection was associated with delayed union. Short-term high-dose dexamethasone predisposed to complicated fracture union, especially in patients with angle fractures. The relationship between dexamethasone and delayed bone healing without infection remains unresolved.

Imaging characteristics of ameloblastomas and diagnostic value of computed tomography and magnetic resonance imaging in a series of 26 patients.

OBJECTIVES: To evaluate the imaging characteristics of ameloblastomas and to analyze the diagnostic value of computed tomography (CT) and magnetic resonance imaging (MRI) compared with conventional dentoalveolar imaging. STUDY DESIGN: In this observational retrospective study, the panoramic radiographs (n = 25) and the CT (n = 26) and MRI (n = 5) images of histopathologically verified ameloblastomas in 26 patients were reviewed. RESULTS: Characteristic findings were multilocularity, marked expansion of the cortical plate, perforation at an earlier stage, and extensive root resorption. On contrast-enhanced CT or MRI, the majority (14 of 17) of the nonunicystic ameloblastomas contained a mixed cystic and solid pattern. Unicystic ameloblastomas (n = 6) and ameloblastomas derived from the cyst epithelium (n = 2) showed thick rim enhancement or a mural solid component in an otherwise cystic lesion. CONCLUSIONS: Contrast-enhanced CT and MRI greatly aid in distinguishing between ameloblastomas and other cystlike lesions because they allow for visualization of the mixed cystic and solid content characteristic of nonunicystic ameloblastomas. The differential diagnostic value of CT and MRI is significant with regard to unicystic ameloblastomas.

Availability of CBCT and iatrogenic alveolar nerve injuries.

OBJECTIVE: To examine whether the rapid increase in the availability of cone-beam computed tomography (CBCT) has changed the number of inferior alveolar nerve (IAN) injuries related to the removal of mandibular third molars in Finland. The hypothesis was that the number of nerve injuries should diminish due to better imaging methods. MATERIALS AND METHODS: The number of CBCT devices, the annual number of CBCT examinations and the number of permanent IAN injuries occurring between 1997 and 2007 were analyzed. The data was collected from three national registers: the Radiation and Nuclear Safety Authority, the Social Insurance Institution and the Patient Insurance Centre. A detailed analysis was made from the cases of permanent IAN injuries. RESULTS: The first CBCT device was registered in 2002 and the cumulative number of these devices in 2009 was 22. There was an increase from 555 to 3160 in the number of annual CBCT examinations during the period 2004-2009. The total number of permanent IAN injuries during the years 1997-2007 was 129 and remained stable throughout the period (regression analysis, p = 0.974, r (2) = 0.01). CONCLUSIONS: Contrary to this hypothesis, the availability of CBCT devices has had no significant influence on the number of IAN injuries related to mandibular third molar removals in Finland. More education should be given to optimize the use of CBCT to cover difficult cases that may give rise to complications.

A rare case of oral epithelioid sarcoma of the gingiva.

Epithelioid sarcoma (ES) is a rare malignant soft tissue tumor. ES can be classified into proximal, distal, and fibroma-like subtypes. These tumors show both mesenchymal and epithelial immunophenotypes. Microscopically, the proximal type ES is usually characterized by nodules of spindle and epithelioid cells growing in granuloma-like pattern often presenting with central necrosis. Immunohistochemically these tumors are vimentin, pancytokeratin, and usually EMA (80%) positive. CD34 (50%) and CD99 (25%) may be positive, and occasionally SMA and S-100 immunopositivity has been reported. No specific genetic alterations have been found in ES. As far as we know, this is the first case in the literature to present ES in gingival mucosa.

Computerized tomography findings and recurrence of keratocystic odontogenic tumor of the mandible and maxillofacial region in a series of 46 patients.

OBJECTIVES: The aim of this study was to evaluate the computerized tomography (CT) features of keratocystic odontogenic tumors (KCOTs). Another aim was to determine the recurrence rate of KCOTs during a mean follow-up of 4.7 years. STUDY DESIGN: The CT features of histopathologically verified KCOTs in 46 patients were reviewed. The features examined included the shape of the lesion, the lesion's influence on surrounding structures, such as cortical bone and teeth, and the behavior of contrast medium. The recurrence rate and the time to recurrence were determined in the series. RESULTS: In the body of the mandible, KCOTs demonstrated only minimal cortical expansion. The vast majority of the lesions caused border scalloping in both jaws. In the maxilla, this could be demonstrated only by CT. Increased attenuation within the tumor cavity that did not show enhancement was evident in 30% of cases. Recurrences occurred in 39% of the patients, with a mean time to a recurrence of 2.2 years. CONCLUSIONS: The CT features that should arouse suspicion of a KCOT include high attenuation areas in the inner part of the lesion, minimal expansion in the body of the mandible, and border scalloping. The high recurrence rate of KCOT makes periodic and long-term follow-up important. The importance of CT imaging in the follow-up is stressed, especially in the maxilla because of its complex 3-dimensional anatomy.

Cystic neck lesions: clinical, radiological and differential diagnostic considerations.

CONCLUSIONS: Metastatic disease should always be considered as a potential differential diagnosis in the adult patient with a cystic neck lesion. OBJECTIVES: The most common cause of a cystic neck lesion in young adults is a branchial cleft cyst (BCC). In older patients metastatic lymph nodes may be easily misdiagnosed as BCC. This study aimed to investigate the incidence of unsuspected carcinoma in routinely excised cervical cysts at a tertiary care teaching hospital and to determine the characteristics of benign BCC and cystic malignancy in preoperative imaging. PATIENTS AND METHODS: A total of 196 consecutive adult patients operated on with the initial diagnosis of benign lateral cervical cyst were identified and the hospital charts and imaging studies were reviewed. The mean age of the patients was 40 years (range 17-79 years). RESULTS: Metastatic squamous cell carcinoma was demonstrated histologically postoperatively in six (3.1%) patients and metastatic papillary thyroid carcinoma in one (0.5%) patient. Therefore, the incidence of unsuspected carcinoma in the cystic neck lesions initially diagnosed as BCC was 3.6%. The preoperative imaging appearances of these lesions had been considered identical to that of BCC.

Apical root resorption after orthodontic treatment -- a retrospective study.

The purpose of the study was to compare the incidence and severity of apical root resorption in patients treated with different orthodontic appliances and to evaluate the effect of treatment duration on the degree of apical root resorption. A further aim was to analyse the degree of apical root resorption in different tooth groups in patients presenting with root resorption. The sample consisted of 625 patients (269 males, 356 females) aged 8-16 years at the beginning of treatment. Active removable plates and fixed appliances were used most frequently. Following exclusion of poor quality radiographs, the final sample included 601 patients (348 females, 253 males). Root resorption in all tooth groups, except third molars, was evaluated from pre- and post-treatment panoramic radiographs. The correlation of root resorption with treatment modality and duration was studied using multinomial logistic regression analysis. Of the tooth groups, maxillary incisors showed apical root resorption most frequently, followed by the mandibular incisors. Root resorption was significantly correlated with fixed appliance treatment (P < 0.001). In addition, the duration of fixed appliances treatment was found to contribute significantly (P < 0.01) to the degree of root resorption. The mean duration of treatment in patients without root resorption was 1.5 years, whereas in those with severe resorption was 2.3 years. The most severe resorption was seen in the maxillary incisors and premolars. It is concluded that with a long duration of fixed appliance treatment, the risk of severe resorption increases. In patients where treatment is prolonged, a 6-month radiographic follow-up is recommended.

Matrix metalloproteinase-1 and -8 in gingival crevicular fluid during orthodontic tooth movement: a pilot study during 1 month of follow-up after fixed appliance activation.

The role of matrix metalloproteinases (MMPs) in response to mechanical forces in orthodontic tooth movement has only been partially clarified. In the present in vivo pilot study, the presence, levels, and degree of activation of MMP-1 and -8 were measured daily for 1 month in gingival crevicular fluid (GCF) of patients treated with orthodontic fixed appliances. GCF samples were collected from five orthodontic patients and three controls from one upper or lower central incisor or from one upper canine before fixed appliance activation and every 24 hours for 1 month thereafter. The molecular forms and activation degrees of MMP-1 and -8 in GCF were analysed by Western blotting, and MMP-8 levels determined by immunofluorometric assay (IFMA).IFMA revealed, during the study period, on average 12-fold higher levels (56 +/- 50 versus 4.6 +/- 4 microg/l) of MMP-8 in orthodontic GCF than in control GCF. The MMP-8 levels in orthodontic GCF were lower than those detected in gingivitis and periodontitis GCF, but significantly higher than in control GCF. IFMA analysis was confirmed by Western blot analysis showing elevated MMP-8 levels from orthodontic GCF relative to control GCF. Forty-one per cent of total MMP-8 immunoreactivities were high-molecular weight complexes (>100 kDa), 32 per cent in the 75 kDa pro-polymorphonuclear (PMN)-MMP-8 form, 14 per cent in the 60 kDa active-PMN-MMP-8 form, and 13 per cent in the 55 kDa fibroblast-type pro-MMP-8 form. In the GCF of orthodontic patients no MMP-1 immunoreactivities were detected. MMP-8 and -1 levels in the control GCF were low and not detectable. These results demonstrate that in vivo in human GCF, elevation and partial activation of multiple species of PMN- and fibroblast-type MMP-8 reflect periodontal remodelling during orthodontic tooth movement.

Matrix metalloproteinase -2, -8, -9, and -13 in gingival crevicular fluid of short root anomaly patients.

The aim of the present observational study was to identify and characterize matrix metalloproteinase (MMP) -2, -8, -9, and -13 in gingival crevicular fluid (GCF) of patients with short root anomaly (SRA). GCF samples collected from affected maxillary central incisors and premolars of five SRA patients and five systemically and periodontally healthy controls were analysed using the zymographic technique for gelatinase A and B (MMP-2 and -9) and by Western blot for collagenase -2 and -3 (MMP-8 and -13). SRA GCF revealed MMP-9 (30 per cent of the total gelatinolytic activity), of which 18 per cent was in 90 kDa proform and 12 per cent in 71-82 kDa active form. Moreover, high-molecular weight complexes (37 per cent) and low-molecular size fragmented (33 per cent) gelatinolytic enzymes were detectable. No MMP-8 or -13 immunoreactivities existed. These results may suggest that activation and complex formation of MMP-9 is characteristic of SRA GCF. From the findings it may be assumed that the GCF of SRA teeth has low collagenolytic resorptive or pathological activity.