Variability in the quantification of abrasion on the Bruxcore device.

The rate of abrasion of dental surfaces during short periods of time is difficult to measure clinically, but one quantifiable method is the use of the Bruxcore bruxism monitoring device. The aim of this study was to estimate the interobserver and intraobserver variation in the Bruxcore system using different reading methods. Fifteen volunteers used individually fabricated Bruxcore devices during 4 consecutive nights, and this procedure was repeated after 6 weeks. The abraded areas of the 30 Bruxcore devices were measured by two observers on two occasions and with three methods: microscope without a reference scale; microscope with a reference scale; and a computer-aided system. Intraobserver variation was small (5%), but interobserver variation was statistically significant for all three methods. The computer-aided system was superior to the other two methods. The interaction between Bruxcore values and observers was statistically significant for the microscope methods but not for the computer method. This was a desired property, indicating stability of the computer-aided method over the range of Bruxcore values observed. Small measurement errors, independent of the size of the measurements, can be expected using a trained observer and a computer-aided method for reading the Bruxcore bruxism monitoring device.

Cysts of the nasopalatine duct.

Nasopalatine duct cysts in 70 patients were reexamined clinically and radiographically. 50 of them were also reexamined histopathologically. 20 specimens of normal duct tissue were likewise examined. More than half of the cysts showed clinical symptoms. The form on the radiograph was usually spherical or oval. Only 1 of 5 cysts was heart-shaped; 1 of 10 was unilateral. The mesiodistal width of the cysts ranged from 4-40 mm, with 75% from 6-12 mm. 3 of 4 showed pronounced radiolucency. Every 2nd cyst was completely surrounded by a thin radiopaque border. The histopathological investigation showed small cysts to be present in 1 of 4 clinically and radiographically normal nasopalatine ducts. More than 1 of 4 clinically and radiographically diagnosed cysts lacked histopathological characteristics of a cystic cavity. The type of epithelium in the cysts was independent of the vertical position in the duct.

Lateral periodontal cysts. Clinical, radiographical and histopathological findings.

21 lesions, clinically and radiographically diagnosed as lateral periodontal cysts (LPC), were retrospectively studied. The majority of the lesions were symptomless and were located in the premolar-canine-incisor region and predominantly in the mandible. 15 cases had the typical lining consistent with the diagnosis LPC. Three lesions were odontogenic keratocysts and 3 were inflammatory cysts. It was concluded that cysts in a lateral periodontal position are usually LPC but the diagnoses of keratocyst and inflammatory cyst must be considered.

Diagnosis and treatment of the unicystic ameloblastoma.

Two cases of unicystic ameloblastoma are presented. The lesions were pain-free and expanded the mandible. They were removed by curettage. Recurrent lesions had similar clinical appearances and histological pictures compared to the original lesions. The unicystic ameloblastoma manifested itself as a cystic cavity without solid neoplastic features, which differs from the solid ameloblastoma with regard to the age of the patients and the rate of recurrence. The behavior of the unicystic ameloblastoma was similar to that of the primordial cyst. Despite the obvious risk of recurrence, conservative treatment with enucleation and curettage seemed to be justified in preference to mutilating radical surgery.

A quantitative microradiographic study of mineral content of supragingival and subgingival dental calculus.

This study was undertaken to determine the distribution and concentration of mineral in supragingival and subgingival dental calculus. Extracted incisors and premolars with attached dental calculus were used. After fixation the specimens were dehydrated and embedded in methylmethacrylate and 100-micrometers-thick ground sections were made. Microradiographs were produced and the mineral content in the sections was determined photometrically, using an aluminum step-wedge as a reference system. The distribution of the mineral varied considerably within the specimens and between different specimens. Supragingival calculus appeared heterogeneous and often stratified, containing areas that seemed to be non-calcified. The average mineral content was 37% by volume. By contrast subgingival calculus appeared homogeneously calcified, with an average mineral content of 58%. No differences in mineral content between surface areas and portions close to the tooth were seen. This indicates that once the calculus is formed no changes occur in the mineral content, i.e. no maturation occurs with age. Local variations in mineral content within the calculus might be explained by periodic differences in the fluid environment of the microbial plaque.

Effect of nystatin in the treatment of denture stomatitis.

The effect of nystatin treatment on denture stomatitis subclassified as generalized simple inflammation and inflammatory papillary hyperplasia has been studied. Twenty-four patients were carefully instructed to apply a thin layer of nystatin dusting powder on the fitting surface of the maxillary denture three times a day for 14 d. Different parameters were studied on three occasions; at the beginning of experiment and after 14 and 28 d. An untreated group of 24 patients with the same types of denture stomatitis served as control. The effect of treatment was evaluated by changes in the clinical erythema, the yeast colonization obtained by mycologic sampling on the palatal mucosa and on the denture base, and changes in the histologic picture of the mucosa obtained by biopsy. Subepithelial inflammation, leukocyte penetration, edema and thickness of the epithelium were histologic parameters. After 14 d of treatment the experimental group compared with the control group showed a statistically significant decrease in palatal erythema and in the amount of yeast colonies. No significant changes were found microscopically. Twenty-eight days after start, i.e. 14 d after withdrawal of the nystatin, there still was a statistically significant improvement of the palatal erythema in the experimental group compared with the controls. However, no patient was totally cured. There were no significant changes in the number of yeast colonies and the histologic parameters.

Content and distribution of glycogen in oral epithelial dysplasia.

Forty-four oral lesions with epithelial dysplasia and 25 other benign and malignant lesions of the oral mucosa were examined after staining with hematoxylin-eosin and diastase controlled PAS. The intensity of the PAS-positivity for glycogen, the grade of dysplasia, the type of keratinization and the degree of subepithelial inflammation were recorded. Histologically normal epithelium at the margins of the lesions were used as controls. The presence and amount of glycogen in normal epithelium at the margins of the lesions were used as controls. The presence and amount of glycogen in normal epithelium at the margin of the lesions were used as controls. The presence and amount of glycogen in normal epithelium varied with the form of keratinization in that non- or parakeratinized epithelium was rich in glycogen whereas there was a negative glycogen-reaction in orthokeratinized epithelium. The most striking feature was an abrupt limitation of the glycogen at the junction between nondysplastic and dysplastic epithelium. The difference in the amount of glycogen in normal and dysplastic epithelium as assessed semiquantitatively, was statistically significant. There was no statistically significant difference in glycogen content with different degrees of dysplasia. The diastase controlled PAS-staining may therefore be a useful method of distinguishing dysplastic from nondysplastic epithelium in doubtful cases. Pseudoepitheliomatous hyperplastic epithelium covering granular cell myoblastoma did not contain any glycogen. Five of six squamous cell carcinomas and four verrucous carcinomas contained no demonstrable glycogen. Glycogen was present in the epithelium of the cases of lichen planus and "denture hyperplasia" investigated.

Benign osteoblastoma associated with an aneurysmal bone cyst of the mandibular ramus and condyle.

This article reviews the clinical behavior, the histologic conditions, and the treatment of a benign osteoblastoma associated with an aneurysmal bone cyst of the mandibular condyle and ramus. A 14-year-old boy, otherwise healthy, was referred for pain and enlargement in his right temporomandibular joint-cheek region. The swelling was firm and tender, a slight facial asymmetry was present, and the mouth-opening capacity was reduced. During a 6-weeks period from the primary examination to surgery the lesion expanded extensively, anesthesia appeared in the right inferior alveolar nerve and a lateral open bite developed on the affected side. Computed tomography displayed a total destruction of the right mandibular condyle and ramus to the level of the mandibular foramen. The lesion was radiolucent without distinct borders to adjacent bone. Surgery revealed a bluish, well-vascularized predominantly cystic tumor. The lesion included the temporomandibular joint disk but without overgrowth to the temporal component. After resection of the lesion, the condyle and the mandibular ramus was reconstructed with the use of an autogenous costochondral graft. The postoperative healing was uncomplicated. At follow-up 2 years after surgery the boy was free of recurrence with normal motor and sensory nerve function.

Radiographic signs of temporomandibular disorders to predict outcome of treatment.

In 32 consecutive patients with temporomandibular disorders radiographic changes were correlated with the patients' assessment of treatment outcome. The patients had been referred for tomographic examination because the clinical signs and anamnestic data were inadequate for definite clinical diagnosis. Initially all patients were treated conservatively with a flat occlusal splint. Surgery was advised in appropriate cases. The subjective effect of treatment was assessed using a questionnaire, and the material was divided into responder and nonresponder groups. Seventy-eight percent (25) of the patients experienced a positive subjective response to the treatment. No radiographic sign was found to be statistically correlated to the outcome of treatment.

A combined clinical, mycological and histological study of denture stomatitis.

The clinical and histological appearance of the different types of denture stomatitis are in many respects very similar and confluent. In order to study the correlation between clinical and histological appearance and amount of yeasts, 48 patients with denture stomatitis and 24 with a healthy palatal mucosa were examined. The terms atrophic and hyperplastic denture stomatitis were introduced. The intensity of the palatal erythema and the growth of yeasts were most prominent among patients with hyperplastic lesions. Dryness and soreness of the mouth, angular cheilitis, spontaneous hemorrhage, glossitis and leukoplakias were found to a varying extent. No statistical evidence of correlation between the intensity of clinical erythema, amount of yeasts and grade of subepithelial inflammation could be found. The disease has most certainly a background other than solely increased growth of yeasts.

Lipidhistochemical and microradiographic study of distribution of lipids in relation to mineral content in dentin caries.

Fifteen human molars were investigated using lipidhistochemical and microradiographic methods. A peripheral necrotic and totally decalcified part of the carious lesion revealed a markedly positive staining reaction for sphingomyelin, sulfatides, cholesterol- and/or triglyceride-esters. The reaction was probably conditioned by the presence of debris and plaque within this area. Pulpally and immediately below the necrotic zone, an area of demineralization was found which on the microradiographs appeared as a radiolucent zone. The zone showed a mineral gradient with an increasing mineral content towards the pulp. In the zone of demineralization a positive reaction occurred for sphingomyelin decreasing in a pulpal direction with increasing mineral content. A weakly positive reaction for cholesterol- and/or triglyceride-esters was also detected but only in the most pulpal part of the zone of demineralization; the intensity of the staining reaction was comparable to that found in normal dentin. In those areas which were represented by a sclerotized, radiopaque zone, only a very weak reaction for sphingomyelin, cholesterol-and/or triglyceride-esters could be observed of the same staining intensity as in normal dentin. The region between the lesion and the pulp showed the same staining intensity as normal dentin.

Clinical signs in patients with disk displacement versus patients with myogenic craniomandibular disorders.

Patients with disorders of the masticatory system were clinically examined with reference to tender TMJs and sore muscles of the head and neck, jaw movement range, occlusal interferences, and aberrations of the bite. The 158 patients were divided into three groups according to diagnosis: 46 with reducing disk displacement, 57 with nonreducing disk displacement, and 55 with myogenic CMD. Unilateral symptoms were found in 83% of the two TMJ groups and 47% of the myogenic CMD group. At intraoral palpation, significantly more patients with nonreducing disk displacement displayed tender sites on the symptomatic side. Tender TMJ, crepitation, and restricted condylar translation on the symptom side were significantly more common in the group with nonreducing disk displacement. Mean maximal mouth opening was 31 mm in the nonreducing disk displacement, 42 mm in the reducing disk displacement, and 47 mm in the myogenic CMD group. Total laterotrusion was significantly less in the nonreducing disk displacement group. Myogenic CMD patients had more interferences in retruded position on the symptomatic side and more tender neck and shoulder muscles. Patients with nonreducing disk displacement displayed more signs from the masticatory system than those with myogenic CMD.

Loss of directional orientation control of lower jaw movements in persons with internal derangement of the temporomandibular joint.

Lateral mandibular movements were performed on command by 50 patients with TMJ disk displacement associated with severe pain. In 22 patients the displacement was reversible, and in 28 patients it was permanent. An additional 50 patients with disorders of the masticatory system other than disk displacement were examined, as well as a group of 50 subjects without any signs or symptoms involving the masticatory system. The results showed that 22 patients (4 with reversible and 18 with permanent disk displacement) failed to move the mandible without tooth contact toward a predetermined direction and, instead, moved it in the opposite direction. The persons themselves were convinced that the direction of movement was correct. If finger pressure was applied to the joint area on the affected side, 25% of the patients with loss of directional control were able to move correctly. A normalization of the directional control was attained in 20% of the cases if lateral movements were performed with light tooth contact. All the patients with disorders of the masticatory system other than anterior disk displacement demonstrated a correct lateral mandibular movement pattern. In the control group, 2% demonstrated incapability of directional control of lateral jaw movements. The results indicate that loss of directional control of the lower jaw is associated with disk displacement.

Frequency of bilateral temporomandibular joint disc displacement in patients with unilateral symptoms: a 5-year follow-up of the asymptomatic joint. A clinical and arthrotomographic study.

Bilateral arthrotomography was performed in 50 consecutive patients with unilateral symptoms of disc displacement to evaluate the frequency of temporomandibular joint disc displacement in asymptomatic joints. Using well-defined clinical criteria, there were no false-positive findings of either reducing or non-reducing discs. On the other hand, a risk of false-negative diagnosis of non-reducing disc was apparent. Sixty per cent of the patients had a non-reducing displaced disc in the asymptomatic joint. Most of these patients could recall a previous spell of discomfort from this joint. Severe or moderate deformation had taken place in non-reducing discs, while reducing discs were normal in shape or had, at most, a thickening of the posterior band. The duration of symptoms was significantly correlated with the degree of deformation in the symptomatic joints (P less than 0.01). Perforation was statistically, significantly correlated with disc deformation and, in symptomatic joints, hard tissue changes. Fifty-seven per cent of the asymptomatic joints with displaced discs developed pain following the onset of symptoms from the contralateral side, most within 2 years. Less than half of them were free of pain at the end of the 5 year follow-up period. In view of this tendency for an asymptomatic joint with a displaced disc to subsequently develop pain refractory to treatment, such a joint must be considered a weakened link in the craniomandibular system, vulnerable to changes in mandibular function such as, for instance, displacement of the disc on the contralateral side.

The anesthetic onset and duration of a new lidocaine/prilocaine gel intra-pocket anesthetic (Oraqix) for periodontal scaling/root planing.

BACKGROUND: A new non-injection anesthetic, lidocaine/prilocaine gel (Oraqix, AstraZeneca) in a reversible thermosetting system, has been developed to provide local anesthesia for scaling/root planing (SRP). The aim of this study was to determine the anesthetic onset and duration of the gel for SRP in patients with periodontitis. METHODS: 30 patients were randomized to either 30 s, 2 min, or 5 min of treatment with the gel prior to SRP of a tooth. The gel was applied to periodontal pockets with a blunt applicator. On completion of the SRP of each tooth (2-3 teeth treated/patient), the patients rated their pain on a 100-mm visual analogue scale (VAS). RESULTS: The median VAS pain score was 7.5 mm in the 30-s group, 28.5 mm in the 2-min group, and 15.5 mm in the 5-min group, with a significant difference between the 30-s and 2-min groups (p=0.03). In 2 patients in the 5-min group, but none in the other groups, the SRP was interrupted due to pain. The mean duration of anesthesia measured as pain on probing were 18.1, 17.3, and 19.9 min in the 30-s, 2-min, and 5-min groups, respectively. There were no reports of numbness of the tongue, lip, or cheek, neither were there any adverse local reactions in the oral mucosa. The gel was easy to apply and did not interfere with the SRP procedure. CONCLUSION: Oraqix provides anesthesia after an application time of 30 s, with a mean duration of action of about 17 to 20 min.

Surgery in the treatment of denture-related inflammatory papillary hyperplasia of the plate.

Twenty patients with denture-related papillary hyperplasia of the palate were surgically treated after careful instruction in oral and denture hygiene, insertion of new dentures and nutritional information. A tissue conditioner was used to cause detumescence of the palatal mucosa presurgically and to act as a wound dressing postsurgically. A knife with a semicircular blade made it possible to cut and plane off the papillary hyperplasia in all regions of the palate and accurately to control and vary the thickness of the extirpated tissue. The advantages of this gentle planning surgery were a short healing time (mean 12 days), no bleeding and no pain that necessitated the use of analgetics. After surgery a persistent erythema of the palatal mucosa appeared in five patients. Such a low rate of postsurgical erythema has not previously been reported. A microscopic examination of the extirpated tissue was performed and the findings are discussed.

Recurrent central odontogenic fibroma.

This article presents a case of a central odontogenic fibroma which recurred 9 years after it was enucleated. Very few cases of this tumor have been recognized and reported. The clinical and histopathologic criteria and the differential diagnosis of the lesion are stressed.

The effect of calcium hydroxide and fluorides on human dentine.

With the aid of scanning electron microscopy and microradiography, 45 teeth including 20 contralateral tooth pairs were studied to assess the effect on human dentine of (1) a 1 minute treatment with 3% NaF, (2) a dressing of Ca(OH)2 and (3) a dressing of Ca(OH)2 and CaPO3F after follow-up periods of 2-8 weeks. After NaF treatment the SEM revealed no sign of obliteration of the dentinal tubules, and on microradiograms no indication of increased density could be registered compared to an untreated control area. Under the calcium dressing the SEM revealed in 13 cases out of 20 (5 cases of 11 intrapair comparisons) a varying degree of constriction of the dentinal tubules. Constrictions varied from one tubule to another and ceased approximately 0.1 mm in the dentine. On the microradiograms no significant difference could be registered between untreated dentine and dentine treated with the calcium dressings. Dressings of Ca(OH)2 a combination of Ca(OH)2 and CaPO3F for 2 months, or a 1 minute treatment with a cavity cleaner containing 3% NaF can thus not be considered to result in a reliable obliteration of the dentinal tubules.