Soft tissue response to mandibular advancement using 3D CBCT scanning

This prospective longitudinal study assessed the 3D soft tissue changes following mandibular advancement surgery. Cranial base registration was performed for superimposition of virtual models built from cone beam computed tomography (CBCT) volumes. Displacements at the soft and hard tissue chin (n = 20), lower incisors and lower lip (n = 21) were computed for presurgery to splint removal (4-6-week surgical outcome), presurgery to 1 year postsurgery (1-year surgical outcome), and splint removal to 1 year postsurgery (postsurgical adaptation). Qualitative evaluations of color maps illustrated the surgical changes and postsurgical adaptations, but only the lower lip showed statistically significant postsurgical adaptations. Soft and hard tissue chin changes were significantly correlated for each of the intervals evaluated: presurgery to splint removal (r = 0.92), presurgery to 1 year postsurgery (r = 0.86), and splint removal to 1 year postsurgery (r = 0.77). A statistically significant correlation between lower incisor and lower lip was found only between presurgery and 1 year postsurgery (r = 0.55). At 1 year after surgery, 31% of the lower lip changes were explained by changes in the lower incisor position while 73% of the soft tissue chin changes were explained by the hard chin. This study suggests that 3D soft tissue response to mandibular advancement surgery is markedly variable.     

Leiomyomatous hamartoma of the midline maxillary gingival presenting as a congenital epulis: a case report with an immunohistochemical study

An otherwise-healthy 2-year-old Japanese female presented with a polyp-like lesion on the palatal surface at the incisive papilla. The appearance of the lesion was similar to that of a congenital epulis. The histological findings showed proliferating mesenchymal components that contained mainly smooth muscle admixed with collagen fibres, nerve fibres, small vessels and mucous salivary glands. The immunohistochemical staining findings for α-smooth-muscle actin, desmin and S-100 protein were all positive. The histological diagnosis was therefore leiomyomatous hamartoma, based on clinical microscopic observations.     

Reconstruction of facial nerve injuries in children

Facial nerve trauma is uncommon in children, and many spontaneously recover some function; nonetheless, loss of facial nerve activity leads to functional impairment of ocular and oral sphincters and nasal orifice. In many cases, the impediment posed by facial asymmetry and reduced mimetic function more significantly affects the child's psychosocial interactions. As such, reconstruction of the facial nerve affords great benefits in quality of life. The therapeutic strategy is dependent on numerous factors, including the cause of facial nerve injury, the deficit, the prognosis for recovery, and the time elapsed since the injury. The options for treatment include a diverse range of surgical techniques including static lifts and slings, nerve repairs, nerve grafts and nerve transfers, regional, and microvascular free muscle transfer. We review our strategies for addressing facial nerve injuries in children.     

Histologic evaluation of the buccal and lingual bone plates in anterior dog teeth: possible influence on implant dentistry

Background: Recent studies in animals have shown pronounced resorption of buccal bone plate after immediate implantation. The sectioning of experimental material for histologic evaluation of the bone plates could provide valuable information about the possible effect of bone exposure in periodontal and implant surgeries. Methods: Twenty‐four incisors were collected from dogs. After decalcification, the blocks were immersed in paraffin and bucco‐lingual histologic sections were examined under light microscope. Some sections were reserved for immunohistochemical analysis. Results: The bone density, the width of the bone plates, and the percentage of vessels presented in the periodontal ligament and periosteum were analyzed in the buccal and lingual bone plates, which were divided corono‐apically into thirds. The buccal bone plates showed statistically higher bone density compared to the lingual bone plates in the coronal thirds. The width of both bone plates increased from the coronal to the apical third, but all the buccal thirds were significantly thinner compared to the lingual thirds. No statistically significant differences were found between the bone plates for the percentage of area occupied by the blood vessels in the periodontal ligament or periosteum. Conclusion: It is reasonable to conclude that the higher bone density, represented by the lower number of marrow spaces, in association with the thinner aspect of the buccal bone plates made them more fragile to absorb compared to the lingual bone plates, especially during mucoperiosteal procedures.     

Fine needle aspiration biopsy in the oral cavity and head and neck region

The objective of the current study was to evaluate the sensitivity, specificity and accuracy of fine needle aspiration biopsy (FNAB) of submucous nodules from the oral cavity and head and neck region as an auxiliary diagnostic tool. Fifty patients with nodule lesions in the oral cavity and the head and neck region were selected. All of them were submitted to FNAB and to either incisional or excisional biopsy. The diagnoses from the FNABs were compared with the biopsy diagnosis as the gold standard. All the cases of FNAB were analyzed by a single oral pathologist prior to the biopsy diagnosis. The results showed that the sensitivity of FNAB was 75%, its specificity was 96% and its accuracy was 58.8%. The false positive and false negative rates were 6.7% and 13.3%, respectively. The positive predictive value was 86% and the negative predictive value was 93%. The inconclusive rate was 16/50. FNAB displayed a high success rate for identifying both malignant and benign lesions, but a low accuracy for making a final diagnosis.     

Thickness of the anterior maxillary facial bone wall-a retrospective radiographic study using cone beam computed tomography

The purpose of this retrospective radiographic study was to analyze the thickness of the facial bone wall at teeth in the anterior maxilla based on cone beam computed tomography (CBCT) images, since this anatomical structure is important for the selection of an appropriate treatment approach in patients undergoing postextraction implant placement. A total of 125 CBCT scans met the inclusion criteria, resulting in a sample size of 498 teeth. The thickness of the facial bone wall in the respective sagittal scans was measured perpendicular to the long axis of the tooth at two locations: at the crest level (4 mm apical to the cementoenamel junction; MP1) and at the middle of the root (MP2). No existing bone wall was found in 25.7% of all teeth at MP1 and in 10.0% at MP2. The majority of the examined teeth exhibited a thin facial bone wall (< 1 mm; 62.9% at MP1, 80.1% at MP2). A thick bone wall (? 1 mm) was found in only 11.4% of all examined teeth at MP1 and 9.8% at MP2. There was a statistically significant decrease in facial bone wall thickness from the first premolars to the central incisors. The facial bone wall in the crestal area of teeth in the anterior maxilla was either missing or thin in roughly 90.0% of patients. Both a missing and thin facial wall require simultaneous contour augmentation at implant placement because of the well-documented bone resorption that occurs at a thin facial bone wall following tooth extraction. Consequently, radiographic analysis of the facial bone wall using CBCT prior to extraction is recommended for selection of the appropriate treatment approach.     

Global oral health inequalities: oral infections-challenges and approaches

Four oral mucosal infections were identified as Global Oral Health Priorities: (a) HIV and associated viral, bacterial, and fungal infections; (b) tuberculosis; (c) NOMA; and (d) sexually transmitted diseases. Huge global inequalities exist in all four. HIV-associated infections constitute the major challenge. Oral manifestations of AIDS can be specifically diagnostic, indicating a significant role for dentists within health teams. The World Workshops in Oral Health & Disease in AIDS have identified a research program, elements of which are being implemented. Data on oral mucosal involvement in tuberculosis, syphilis, and gonorrhea are incomplete in developed countries and virtually non-existent in low- and middle-income countries, indicating the need for further epidemiological studies. Oral manifestations of tuberculosis and sexually transmitted diseases are largely associated with general health, so action programs should be integrated with agencies treating the systemic diseases. NOMA is very much in the oral health domain. It is a preventable disease associated with malnutrition and unidentified bacterial factors. Prevalence is probably grossly overestimated at present; but nevertheless it constitutes a challenge to the profession, especially in the NOMA belt. Current treatment is surgical, but plans for its eradication should be achievable. The global oral health community, especially the IADR, has a major role to play.     

Surface electromyography of jaw muscles and kinesiographic recordings: diagnostic accuracy for myofascial pain

The present investigations attempted to assess the diagnostic accuracy of commercially available surface electromyography (sEMG) and kinesiography (KG) devices for myofascial pain of jaw muscles. Thirty-six (n = 36) consecutive patients with a research diagnostic criteria for temporomandibular disorders (RDC/TMD) axis I diagnosis of myofascial pain and an age- and sex-matched group of 36 TMD-free asymptomatic subjects underwent sEMG and KG assessments to compare EMG parameters of the masseter and temporalis muscles as well as the jaw range of motion and the interarch freeway space. EMG data at rest were not significantly different between myofascial pain patients and asymptomatic subjects, while the latter achieved significantly higher levels of EMG activity during clenching tasks. Symmetry of muscle activity at rest and during clenching tasks, KG parameters of jaw range of motion and the measurement of the interarch vertical freeway did not differ between groups. Receiver operating characteristics curve analysis showed that, except EMG parameters during clenching tasks, all the other outcome sEMG and KG measures did not reach acceptable levels of sensitivity and specificity, with a 30·6-88·9% percentage of false-positive results. Therefore, clinicians should not use sEMG and KG devices as diagnostic tools for individual patients who might have myofascial pain in the jaw muscles. Whether intended as a stand-alone measurement or as an adjunct to making clinical decisions, such instruments do not meet the standard of reliability and validity required for such usage.