The position of the mental foramen of the local Malays and Indians in Singapore was determined from a series of orthopantomograms. The most frequent location does not conform to the position cited in many anatomy, surgery, and dental anesthesia texts as being below and between the apices of the lower premolars. This data has implications in the teaching and practice of dental anesthesia. In both these races, the median location is just below the second premolar.
Knowledge of the position of the mental foramen is important both when administering regional anesthesia and performing periapical surgery in the mental region of the mandible. This study determines the position of the mental foramen in a selected Malay population. One hundred and sixty nine panoramic radiographs of Malay patients retrieved from a minor oral surgery waiting list were selected to identify the normal range for the position of the mental foramen. The foramen was not included in the study if there was any mandibular tooth missing between the lower left and right first molars (36-46). The findings indicated the most common position for the mental foramen was in line with the longitudinal axis of the second premolar (69.2%) followed by a location between the first and second premolar (19.6%). The right and left foramina were bilaterally symmetrical in three of six recorded positions in 67.7% patients. The mental foramen was most often in line with the second premolar.
The radiographs of fifteen Malaysian patients with presenting ameloblastoma aged between 20-55 years (average 35 years) were studied for any peculiar local features. The most common features were cortical plate expansion (80%), corticated scalloped margin (67%), multiloculation (87%), and resorption of tooth roots (47%). The latter two features are constantly found in advanced tumour stage. As pain was not a frequent complaint, many Malaysian patients seek treatment only at a very late stage after the tumours have reached large dimensions. Although ameloblastomas may be diagnosed often through radiographs, it should not be relied upon solely.
This study evaluated the validity of panoramic radiography and cone beam computed tomography (CBCT) in the assessment of mandibular canal and impacted third molar. In this descriptive-analytical study, 58 mandibular third molars from 42 patients who showed a close relationship between impacted third molar and canal on panoramic radiographs were selected. They were then classified into seven radiographic markers in panoramic radiographs (superimposition, darkening of the root, interruption of the white lines, root narrowing, canal diversion, canal narrowing, and also closed distance in OPG <1mm). The groups of markers were further assessed with CBCT to see presence or absence of contact. The three most common markers seen in panoramic images are superimposition, interruption of white line and root darkening. In CBCT, superimposition marker always presented higher frequency of contact with canal compared to non-contact group. There are 31% of teeth presented with interruption of white lines and there are 29.3% of teeth presented with superimposition. About 55.6% and 35.3% of the impacted mandibular third molars which indicated interruption of white lines and superimposition also indicated contact in the CBCT respectively. Presence or absence of radiological sign in panoramic radiography was not properly predict a close relationship with third molar and it is suggested that in case of tooth-canal overlapping, the patient should be referred for CBCT assessment.
The mandibular incisive nerve can be subjected to iatrogenic injury during bone graft harvesting. Using cone beam computed tomography (CBCT), this study aims to determine a safe zone for bone graft harvesting that avoids injuring this nerve.
The anterior loop is defined as where the mental neurovascular bundle crosses anterior to the mental foramen then doubles back to exit the mental foramen. It cannot be seen clinically but can be detected in 11-60% of panoramic radiographs. As this anatomical structure is important in determining the placement position of endosseous implants in the mandibular premolar region, a pilot study was undertaken to determine its visibility on dental panoramic radiographs in dentate subjects of various age groups. One or more anterior loops were visible in 39 (40.2%) radiographs encompassing 66 sites (34.4%). Interestingly, anterior loops were most commonly observed bilaterally, followed by on the right side of the mandible only. An anterior loop on the left side only was observed in just 1 radiograph. Visibility of anterior loops reduced as the age of subjects increased. More than half (58.1%) of subjects aged 20-29 years exhibited at least one anterior loop; this gradually reduced to only 15 percent of subjects aged 50 and older. There was no association between visualization of the anterior loop and subject gender.
BACKGROUND: Numerous methods of age estimation have been proposed. The Demirjian method is the most frequently used, which was first applied in a French Canadian population in 1973. The Willems method is a modification of the above and was applied in a Belgian population in 2002.
OBJECTIVES: The objectives of this study were to test the applicability of the two methods, namely Demirjian and Willems, for age estimation in a Malay population, and to find the correlation between body mass index and the difference between the dental age and the chronological age.
MATERIALS AND METHODS: A cross-sectional study involving 214 boys and 214 girls, selected by a simple stratified random sampling method was carried out. The orthopantomograph was used to score the seven left mandibular teeth, and the calculated maturity score was used to obtain the Demirjian dental age. Willems dental age was estimated using the tables proposed in the Willems method. Results. The Demirjian method overestimated the age by 0.75 and 0.61 years, while the Willems method overestimated the age by 0.55 and 0.41 years among boys and girls, respectively. In boys, the body mass index was significantly correlated to the difference in age using the Willems method.
CONCLUSION: Further modification of either method is indicated for dental age estimation among the Malay population.
A case of unicystic ameloblastoma which recurred after 15 years showing unusual histological features is reported. The prominent pseudo-glandular features present are described. This case highlights the importance of extensive histological examination for more characteristic features of ameloblastoma to reach a correct diagnosis.
Intermaxillary (IMF) screws feature several advantages over other devices used for intermaxillary fixation, but using cone beam computed tomography (CBCT) scans to determine the safe and danger zones to place these devices for all patients can be expensive. This study aimed to determine the optimal interradicular and buccopalatal/buccolingual spaces for IMF screw placement in the maxilla and mandible. The CBCT volumetric data of 193 patients was used to generate transaxial slices between the second molar on the right to the second molar on the left in both arches. The mean interradicular and buccopalatal/buccolingual distances and standard deviation values were obtained at heights of 2, 5, 8 and 11 mm from the alveolar bone crest. An IMF screw with a diameter of 1.0 mm and length of 7 mm can be placed distal to the canines (2 - 11 mm from the alveolar crest) and less than 8 mm between the molars in the maxilla. In the mandible, the safest position is distal to the first premolar (more than 5 mm) and distal to the second premolar (more than 2 mm). There was a significant difference (p<0.05) between the right and left quadrants. The colour coding 3D template showed the safe and danger zones based on the mesiodistal, buccopalatal and buccolingual distances in the maxilla and mandible.The safest sites for IMF screw insertion in the maxilla were between the canines and first premolars and between the first and second molars. In the mandible, the safest sites were between the first and second premolars and between the second premolar and first molar. However, the IMF screw should not exceed 1.0 mm in diameter and 7 mm in length.
The purpose of this study was to compare bone healing and coronal bone remodeling following both immediate and delayed placement of titanium dental implants in extraction sockets.
A case report of sequestra formation in the oral cavity most probably as a sequelae of periodontal abscess in a diabetic patient is presented. The sequestra probably formed as a complication of uncontrolled diabetes mellitus rather than erythroleukemia. The lesion was located at the bifurcation area of the lower left second molar. Removal of the sequestra, scaling and a course of antibiotics managed to control the lesion.
The objective of this study was to determine whether dental calcification can be used as a first-level diagnostic tool for assessment of skeletal maturity.