Ramizu Shaari

Multivariate analysis of factors affecting presence and/or agenesis of third molar tooth.

To investigate the presence and/or agenesis of third molar (M3) tooth germs in orthodontics patients in Malaysian Malay and Chinese population and evaluate the relationship between presence and/or agenesis of M3 with different skeletal malocclusion patterns and sagittal maxillomandibular jaw dimensions. Pretreatment records of 300 orthodontic patients (140 males and 160 females, 219 Malaysian Malay and 81 Chinese, average age was 16.27±4.59) were used. Third-molar agenesis was calculated with respect to race, genders, number of missing teeth, jaws, skeletal malocclusion patterns and sagittal maxillomandibular jaw dimensions. The Pearson chi-square test and ANOVA was performed to determine potential differences. Associations between various factors and M3 presence/agenesis groups were assessed using logistic regression analysis. The percentages of subjects with 1 or more M3 agenesis were 30%, 33% and 31% in the Malaysian Malay, Chinese and total population, respectively. Overall prevalence of M3 agenesis in male and female was equal (P>0.05). The frequency of the agenesis of M3s is greater in maxilla as well in the right side (P>0.05). The prevalence of M3 agenesis in those with a Class III and Class II malocclusion was relatively higher in Malaysian Malay and Malaysian Chinese population respectively. Using stepwise regression analyses, significant associations were found between Mx (P<0.05) and ANB (P<0.05) and M3 agenesis. This multivariate analysis suggested that Mx and ANB were significantly correlated with the M3 presence/agenesis.

White-eyed blowout fracture: Diagnostic pitfalls and review of literature

White-eyed blowout fracture was first termed by Jordan et al. in individuals sustaining a blow to the periocular area and presenting with ocular symptoms, although with minimal soft tissue signs of trauma. It is often found in pure orbital floor blowout fractures among paediatric patients, and it could manifest as a linear or hinge-like trapdoor deformity. Unlike the more common open orbital blowout fractures with distinct diagnostic clinical signs, white-eyed blowout fractures are rarer and their diagnoses can be easily missed, subsequently costing an optimal time window for surgical intervention. This is critical as better outcomes are found with earlier release of entrapments. This report describes a case of a white-eyed blowout fracture in a 10-year-old child faced with its diagnostic challenges. The current literature review discusses the types of fracture pattern, signs and symptoms, mechanism of action, as well as timing of surgery. In view of the common complication of persistent diplopia, clinical pitfalls in achieving this diagnosis are emphasized to prevent any delay of treatment. Current literature evidences are weighted towards urgent surgical intervention, as positive outcomes are found to correlate with earlier release of entrapments.

Morphometric analysis of prognathic and non-prognathic mandibles in relation to BSSO sites using CBCT

BACKGROUND Bilateral sagittal split osteotomy (BSSO) is the most versatile procedure and adopted by many surgeons to relocate the mandible in patients having mandibular prognathism (MP). Injury to the inferior alveolar nerve (IAN) and unfavorable splits are two surgical complications of BSSO which are associated with mandibular morphology. Uses of cone beam computed tomography (CBCT) in providing 3-D images has gained a wider acceptance in surgical field nowadays. Its advantages are including reduced cost, lesser radiation dose and smaller physical footprint comparing to the conventional computed tomography. PURPOSE This study aims to identify the differences in morphology of prognathic and non-prognathic mandible at BSSO sites using cone beam computed tomography images. METHODS This retrospective study involved 51 CBCT images of patients having mandibular prognathism and without mandibular prognathism. The latter group made up from patients with Class I skeletal pattern. Samples were taken using purposive sampling method from two clinical centers. RESULT Prognathic mandible has higher lingula level, superiorly and buccally placed inferior alveolar nerve canal at distal second molar, thinner mediolateral width of ramus at anterior and posterior part and thinner anteroposterior width of the ramus. CONCLUSION Morphology of mandible in patients with mandibular prognathism (MP) was significantly different from patients without mandibular prognathism (WMP) for most of the parameters. The high risk parameters may be highlighted to the patients using cone beam computed tomography images.