A clinical comparison of extraoral panoramic and intraoral radiographic modalities for detecting proximal caries and visualizing open posterior interproximal contacts.

OBJECTIVES: The purpose of this study was to compare extraoral panoramic bitewings (BWs) to intraoral photostimulable phosphor (PSP) plate BWs for the detection of proximal surface caries and to establish if there was any difference between extraoral BWs, intraoral BWs and panoramic radiographs in visualizing open posterior interproximal contacts. METHODS: Extraoral panoramic and intraoral BW images were acquired on each of 20 patients, resulting in 489 total non-restored, readable surfaces that were evaluated by 4 observers. The ANOVA analysis to determine diagnostic variability between and within each subject was utilized. The surfaces included in the study extended from the distal of each canine to the last posterior contact in each arch with non-readable proximal surfaces excluded (i.e.surfaces where over half the enamel layer was overlapped or where those surfaces were not visible in one or both modalities). RESULTS: The statistical analysis indicated that the overall mean area under the receiver operating characteristic curves across all observers for the intraoral BWs and extraoral panoramic BWs were 0.832 and 0.827, respectively, and the difference of 0.005 was not significant at p = 0.7781. The percentage of non-readable proximal surfaces across the three modalities was 4.1% for intraoral BWs, 18.3% for extraoral panoramic BWs and 51.5% for the standard panoramic images. CONCLUSIONS: The investigators concluded there was no significant difference in posterior proximal surface caries detection between the modalities. Extraoral panoramic BWs were much better than panoramic radiographs in visualizing open posterior interproximal contacts, 81.7% vs 48.5%, but below the 95.9% value for intraoral BWs.

Trigeminal neuralgia: a retrospective study of 188 Thai cases.

OBJECTIVE: To describe the clinical characteristics and treatment of trigeminal neuralgia (TN) in a group of Thai patients. MATERIALS AND METHODS: Records of 188 patients with TN were reviewed retrospectively for patient demographics, the characteristics of the pain and treatment modalities. RESULTS: Of the 188 patients, 37.2% were men and 62.8% were women. The peak incidence (46.8%) was in the age range of 50-69 years. Pain occurred on the right side of the face more often than on the left (1.8:1). The mandibular division of the trigeminal nerve was the most frequently affected (30.3%), followed by the combined maxillary and mandibular divisions (29.3%) and the maxillary division alone (25%). The majority described their attack as a sharp pain (77.6%), and the most common primary locations were at previous extraction sites (40.5%). The most common triggers were chewing (61.2%) and speaking (47.3%). Carbamazepine was the most common prescribed drug (76.1%) for the initial treatment. Combination drug therapy was introduced when the monotherapy failed to control the pain. Surgical intervention was the alternative choice of treatment in refractory cases. CONCLUSION: TN affected women more than men, and this disorder occurred most frequently in patients aged 50 years and older. The mandibular division of the trigeminal nerve was most commonly involved.

Oral mucosal lesions in denture wearers.

OBJECTIVE: To determine the prevalence of oral mucosal lesions (OMLs) and denture-related mucosal lesions (DMLs) in denture wearers and to co-relate the prevalence with age, gender, type of denture and any systemic conditions. MATERIALS AND METHODS: Dental records of 380 denture wearers were retrospectively reviewed for OMLs and DMLs. RESULTS: We found 45% of the denture wearers had DMLs and 60.8% had OMLs not related to denture wearing. Although the prevalence of DMLs was higher in complete denture wearers than in partial denture wearers (49% vs. 42.2%), this difference was not significant. The most common DMLs were traumatic ulcer (19.5%) and denture-induced stomatitis (18.1%). When analysed by type, traumatic ulcer, denture hyperplasia, frictional keratosis and candidiasis were more common in complete denture wearers, whereas denture-induced stomatitis was more common in partial denture wearers. Frictional keratosis was more common in men than in women. The prevalence of OMLs not related to denture wearing was higher in complete denture wearers than in partial denture wearers, and the most common OML was fissured tongue (27.6%). No association between DMLs and systemic conditions or xerostomic drugs was noted. CONCLUSION: No differences in the prevalence of DMLs in association with denture type were found. The prevalence of OMLs not related to denture wearing was higher in complete denture wearers than in partial denture wearers. This difference was affected by age, and the data were similar to the findings observed in the elderly.

Imaging modalities to access bony tumors and hyperplasic reactions of the temporomandibular joint.

Benign and malignant tumors in the temporomandibular joint (TMJ) are rare. However, when a patient presents with clinical findings such as altered occlusion or facial asymmetry, a morphologic alteration in the condyle should be ruled out. The differential diagnosis for benign hyperplastic bony lesions in the TMJ should include condylar hyperplasia, osteochondroma, osteoma, chondroma, and osteoblastoma. If malignant features are present, chondrosarcoma and osteosarcoma should be considered. For the differential diagnosis, imaging is the most noninvasive method to evaluate the integrity of the TMJ. Imaging can be classified as morphologic or functional according to the information provided. The current scientific data have shown that panoramic images have 97% sensitivity and 45% specificity for identifying hyperplastic conditions in the TMJ. The sensitivity and specificity of medical computed tomography (CT) and cone-beam CT is 70% and 100%, and 80% and 100%, respectively, for the detection of bony abnormalities. To differentiate benign and malignant bony tumors, magnetic resonance imaging has a sensitivity and specificity of 44% and 95%, respectively. The corresponding percentages for single positron emission CT are 91% and 94%, for single positron emission CT/CT are 100% and 100%, for positron emission tomography are 88% and 72%, and for positron emission tomography/CT are 100% and 97%. The combination of morphologic and functional (single positron emission CT and positron emission tomography) modalities appears to improve the sensitivity and specificity to assess a hyperplastic condyle, facilitating treatment planning and providing a better prognosis for the patient.

Oral squamous cell carcinoma: a clinicopathological study of 342 Thai cases.

AIM: To conduct a clinicopathological review of oral squamous cell carcinoma (SCC) and to analyze it with respect to gender, age at diagnosis, clinical presentation, lesion location, and histological grading. METHODS AND MATERIALS: Information on the clinicopathological characteristics of SCC was obtained from pathology reports of 342 cases. RESULTS: The male to female ratio was 1:1 and the incidence increased with age. Among the patients 4.7% were younger than 40 years and males were predominant in this subgroup. The alveolar ridge and gingiva were the most commonly affected sites (50%). The majority of the SCC cases presented as ulcers or masses. Swelling and/or pain were the first signs and/or symptoms in most patients (52.6%). The age at diagnosis in relation to the site of occurrence varied. Conventional SCC was the most common subtype (88%). Well-differentiated SCC was the most common histological grading (78.6%). CONCLUSION: In the present study, the incidence of SCC was age-related and showed equal gender distribution. CLINICAL SIGNIFICANCE: Routine examination of the oral cavity by dental practitioners and other health care providers aids in the early detection of premalignant and malignant oral disease. Dentists can play a significant role in disseminating information regarding oral cancer.

Antifungal activity of Morinda citrifolia fruit extract against Candida albicans.

OBJECTIVE: The objective of the study was to investigate the antifungal activity of Morinda citrifolia fruit extract on Candida albicans. MATERIALS AND METHODS: Juice extract from M. citrifolia fruit was lyophilized and used in antifungal testing. Antifungal activity of M. citrifolia fruit extract against C. albicans was tested in vitro at various concentrations and for different contact times. The inhibitory effect of M. citrifolia extract on C. albicans was determined by cultures and an applied broth dilution test. RESULTS: Using cultures, growth of C. albicans was not detected with 50 mg/mL of extract at 30-minute contact time or with 60 mg/mL of extract at 15-minute contact time. By the broth dilution test, the minimum fungicidal concentration of extract against C. albicans was 40 mg/mL at 90-minute contact time or with 50 mg/mL at 15-minute contact time. CONCLUSION: M. citrifolia fruit extract had an antifungal effect on C. albicans and the inhibitory effect varied with concentration and contact time.

Relationship between density variability and imaging volume size in cone-beam computerized tomographic scanning of the maxillofacial region: an in vitro study.

OBJECTIVE: In limited-volume cone-beam computerized tomography (CBCT) imaging, projection data discontinuity caused by maxillofacial hard tissue structures outside the reconstructed volume are reported to affect the density value of the hard and soft tissue structures within the volume. The intensity of this effect is purported to be related to the size of the imaging volume. The aim of this study was to characterize the effect of the size of the scanned volume on density values in vitro. STUDY DESIGN: Test objects were positioned in a custom phantom in the following 4 patterns: bimandible and vertebrae, bimandible, left mandible and vertebrae, and left mandible. We used a newly developed flat panel detector CBCT system (Alphard Vega; Asahi Roentgen, Kyoto, Japan) to acquire scans of the left molar region using cylindrical volumes of approximately 5, 10, 15, and 20 cm in diameter and height. The density values of the mandible and the adjacent soft tissue regions were analyzed. RESULTS: Highest density variability was observed in the smallest-volume (5 cm) scans. Density variability increased when more objects were included outside the area being imaged. Fewer effects were noted in CBCT scans of larger (10, 15, and 20 cm) volumes. CONCLUSION: Larger-volume CBCT scans may yield more consistent density values. Smaller CBCT volumes have the advantages of better image resolution and lower radiation doses. The optimization of the image characteristics is maximized by careful consideration of the purpose of the CBCT examination.

Accuracy of cone beam computed tomography in determining the location of the genial tubercle.

OBJECTIVE: To determine the accuracy of cone beam computed tomography (CT) to predict the location of the genial tubercle. STUDY DESIGN AND SETTING: Cadaver study for anatomic analysis of 17 adult human cadaver heads. Each skull/cadaver head underwent radiographic imaging with cone beam CT and cadaver dissection. Measurements, including mandibular height (MH), genial tubercle width (GTW), genial tubercle height (GTH), distance from inferior border of mandible to genial tubercle (IBM/GT), and mandibular thickness (MT) were recorded. RESULTS: Statistical analysis with paired t test showed no significant difference between cadaver dissections versus cone beam measurements. Ninety-five percent confidence intervals (CI) were as follows: GTW (-0.2 to 1.0), GTH (-0.1 to 0.9), distance IBM/GT (-0.8 to 5.0), MH (-1.3 to -2.6), and MT (-0.1 to 0.3). CONCLUSION: These results show the accuracy of the 3D cone beam CT in the anatomic location of the genial tubercle. SIGNIFICANCE: This radiographic technique may prove useful in pre-operative planning for the mandibular osteotomy in genioglossus advancement procedures.

Effects of image artifacts on gray-value density in limited-volume cone-beam computerized tomography.

OBJECTIVE: An in vitro study was designed to investigate the influence of projection data discontinuity-related artifacts in limited-volume cone-beam computerized tomography (CBCT) imaging of the jaws. STUDY DESIGN: Test objects were positioned in 4 patterns in a water-filled phantom as follows: bimandible and vertebrae, bimandible, left mandible and vertebrae, and left mandible. The CT imaging of the left molar region was performed using image intensifier (II)- and flat panel detector (FPD)-based CBCT scanners. The CT value of the mandible and the adjacent soft tissue region were analyzed for density by means of an 8-bit grayscale. RESULTS: The effects of artifacts were scored as the difference in relative density between the lingual and buccal soft tissue. The intensity of artifacts increased when more objects were presented outside the area being imaged. Fewer artifacts were noted in images produced by the particular FPD CBCT used in this investigation. CONCLUSION: The CBCT system using an FPD resulted in fewer artifacts than the CBCT system using an II in this particular study.

Image artifact in dental cone-beam CT.

PURPOSE: The purpose of this study was to investigate the appearance and possible cause of an artifact seen in limited-volume cone-beam CT imaging. METHODS: A water-filled plastic cylinder was used as a phantom of the head. A test object was constructed as a bone-equivalent phantom to be imaged. The test object was variously positioned at the center of the phantom and near its margins. CT images of the test object were acquired using a 3DX Accuitomo system. RESULTS: In slice images with the test object positioned near the margin of the phantom, arch-shaped defects or deformities were observed on the side of the object. There was a negative correlation between the artifact and the CT value of the object. The artifact was larger in images scanned with a higher voltage. CONCLUSION: The probability that this artifact is caused by halation from the image intensifier (II) system is suggested.

Condylar head remodeling following mandibular setback osteotomy for prognathism: a comparative study of different imaging modalities.

PURPOSE: Condylar remodeling, which develops after mandibular setback osteotomy, was evaluated and compared in CT, plain film radiographs, and MR images acquired postoperatively. METHODS: Thirty-nine patients treated with sagittal split ramus osteotomy (SSRO) and 46 patients treated with intraoral vertical ramus osteotomy (IVRO) were studied. Remodeling as seen in the images and the diagnostic agreement between imaging modalities was evaluated. RESULTS: A newly formed bone layer in the posterior part of the condylar head was identified as a sign suggestive of remodeling. This sign was seen predominantly at periods over 6 months postoperatively. IVRO subjects had a higher incidence of remodeling than did the SSRO group. The diagnostic agreement between the 3 imaging modalities was substantial. There was a positive correlation between postoperative condylar displacement and the incidence of remodeling. CONCLUSIONS: The incidence of postoperative condylar head remodeling may be predictable. High-dose postoperative imaging studies to assess the TMJ should be restricted to those cases having a clear need for such studies.

Geographic tongue: clinical characteristics of 188 cases.

The purpose of this study was to investigate the clinical characteristics and assess other factors associated with geographic tongue in Thailand. One hundred and eighty-eight Thais with geographic tongue and 188 controls were interviewed regarding their medical history, symptoms, and the nature and migratory pattern of their lesions. Variations in the clinical appearance, lesion location, and any associated tongue fissures were recorded. The age range for the 188 subjects was 9 to 79 years. The highest incidence (39.4%) occurred in the 20-29 age group. Women were affected more than men (1.5:1). The leading group of medical conditions consisted of allergy-related disorders; however, the incidence of these problems among both subjects and controls was not significantly different (55.2% vs. 44.8%). Our results demonstrated a significant co-existence of geographic tongue and fissured tongue. Most of the geographic tongue lesions manifested a typical appearance consisting of a central atrophic area bounded by a raised white circinate line (69.1%) with multiple tongue sites affected (62.8%). The most common locations were at the lateral margins and tip of the tongue. The majority of our subjects (75.5%) were asymptomatic. The results of this study correspond with the findings of previous geographic tongue studies in other populations.

3D-CT evaluation of facial asymmetry.

OBJECTIVE: Recently, 3-dimensional-computed tomography (3D-CT) imaging has been used in the diagnosis and surgical treatment planning of patients with craniofacial deformities. The present authors have developed a 3D-CT imaging procedure for a 3-dimensional coordinate point evaluation system to assess and diagnose patients with facial asymmetry. STUDY DESIGN: The CT data of 16 subjects was selected retrospectively as the control group from patients who had undergone CT examinations to diagnose conditions other than maxillofacial deformities. Anatomical landmarks modified from orthodontic craniometric (cephalometric) points were defined on the 3D-CT images and the asymmetry index of each point was calculated in millimeters. A diagrammatic chart with a baseline indicating the mean asymmetry indices plus the standard deviation in the control group was designed. The resulting diagrammatic chart was used to evaluate the degree of deformity in facial asymmetry patients. RESULTS AND CONCLUSIONS: The topography of facial asymmetry was assessed. The 3D-CT imaging technique as described herein is a practical method of evaluating the morphology of facial asymmetry.

3D CT evaluation of masseter muscle morphology after setback osteotomy for mandibular prognathism.

OBJECTIVE: Following mandibular setback osteotomy, changes in the direction, length, and cross-sectional area of the masseter muscle were studied by means of computerized tomography (CT) images generated with a 3-dimensional (3D) reconstructive technique. STUDY DESIGN: Pre- and postoperative CT examinations were performed on 17 prognathic patients treated by sagittal split ramus osteotomy with rigid osteosynthesis and 13 patients treated by intraoral vertical ramus osteotomy without osteosynthesis. The pre- and postoperative masseter muscle direction and length were evaluated using 3D CT images observed from a lateral viewing angle. The cross-sectional area of the masseter muscle was first measured on an axial CT image of a selected slice level, following which the right-angle cross-sectional area of the muscle was revised using the measured area from the axial image. RESULTS: Postoperatively, anterior tilting of the masseter muscle was observed; however, masseter muscle length was unchanged. Three months postoperatively, a significant reduction in the cross-sectional area of the masseter muscle was seen. A tendency to revert back to the normal dimension was seen between 6 months and 1 year postoperatively. No significant difference was noted between the 2 surgical techniques. CONCLUSIONS: Three-dimensional computed tomography is an adequate imaging modality for masseter muscle evaluation. The results of this study suggest the masseter muscle may undergo reversible atrophy after mandibular setback osteotomy.

Medical health and medication use in elderly dental patients.

The objectives of this study were to obtain information on the medical conditions and medications used among elderly Thai dental patients and to investigate the relationship between the findings in relation to age and sex. The information regarding medical conditions and medication use was obtained from interviews of 510 dental patients aged 60 years and older. The incidence of medical conditions was 82.5%; women had a significantly higher incidence of medical conditions (86.5%) than men (76.5%). The incidence of medical conditions did not differ among the three age groups. Overall, cardiovascular disease was the leading problem (33.7%) with hypertension being the major component (26.1%). The prevalent problems were bone/joint disorders (32.4%), allergies (18.2%), diabetes mellitus (14.5%), and eye and ear problems (14.3%). In our sample, 65.5% reported taking medications, with an average of 1.5 drug groups per person. The average number of medications taken increased as age increased. Women took medications more frequently than men (70% vs. 58.5%). The four most prevalent drugs were cardiovascular agents (32%), endocrinologic drugs (14.5%), nutritional therapeutics (12.9%), and drugs acting on the musculoskeletal system (11.4%). The present study supports the findings of previous reports in that the presence of medical conditions is high in the elderly and the incidence of medication use increases with advancing age.