Maxillary palatal expansion has several relevant uses, including correction of transverse discrepancies and maxillary constriction, improving masticatory function, and improving the airway volume of the nasopharynx. Mid-palatal expansion can be completed by splitting the median suture with either a bone-borne or a tooth-borne expander. If the bone filled in is adequate, a permanent change in the transverse dimension of the maxilla can benefit the patient.

It has been noted that retention time plays a major role in the amount of relapse that takes place. A period of 90 days, or roughly 3 months, has been recommended for retention to allow for bone to adequately fill in. However, bony filling time can vary from individual to individual; for example, males and females have different rates of bone growth and bone densities.

To study the effects of different retention times, 28 Sprague-Dawley rats were divided into 10 groups (control n=2 male, control n=2 female, 1 week expansion male n=3, 1 week expansion female n=3, 1 week retention male n=3, 1 week retention female n=3, 2 week retention female n=3, 2 week retention male n=3, 4 week retention female n=3, 4 week retention male n=3). Rats were given a helical spring expander, placed to expand the maxillary incisors. After 7 days of expansion, 6 rats were sacrificed (3 male, 3 female) and the remaining rats had their expanders converted into retention devices. 6 rats (3 male, 3 female) were sacrificed at 1 week retention, 2 week retention, and 4 week retention each to observe bony changes. The bone volume was quantified by microCT analysis and histological analyses were completed to quantify mineralized area.

The relapse ratio was not significant, as the retentive device held the expansion adequately. It is noted that while bone mineral density (BMD) did not have any significant differences among groups, bone volume over total volume (BV/TV) and mineralized area over total area (MA/TA) were significantly different between the first and second weeks of retention. By week 4 retention, BV/TV and MA/TA values were at their highest.

The purpose of this study is to evaluate the levels of various cytokines in patients with idiopathic condylar resorption (ICR) of the temporomandibular joint (TMJ). Previous research has assessed the roles of cytokines in serum and synovial fluid of patients with autoimmune diseases resulting in joint degeneration. However, limited studies have assessed saliva as an alternative medium for detection of cytokine levels in ICR. Whole saliva was collected and compared between 10 ICR subjects and 10 control subjects. Using membrane-based protein assay, we found an increase in intensity in the following 12 proinflammatory cytokines: IL-18, IFN-γ, IL-1α, IL-1β, IL-6, TNF-α, IL-17A, IL-17E, GM-CSF, CXCL10, CCL5, and CCL2. A decrease in intensity was seen in the anti-inflammmatory cytokine IL-10. IL-18, IFN-γ, IL-6, TNF-α, IL-17A, IL-17E, and GM-CSF demonstrated statistical significance in our analysis (p < 0.05).

Oral premalignancy serves as an ideal model for study of chemopreventive agents. Although 13-cis-retinoic acid showed reversal of oral premalignancy, toxicity, and reversal of clinical response after cessation of therapy obviated its widespread use. A search for nontoxic agents with cancer preventive activity led us to evaluate Bowman Birk Inhibitor (BBI) formulated as BBI Concentrate (BBIC). We previously reported encouraging results in a phase IIa trial of BBIC in patients with oral leukoplakia with measurable clinical responses and favorable biomarker changes. On the basis of these results, we undertook a randomized, placebo controlled phase IIb trial with patients receiving BBIC or placebo for 6 months, with assessment of clinical response and change in lesion area as primary end point and an intent-to-treat analysis. One hundred and thirty two subjects were randomized; and 89 subjects completed six months on study drug or placebo. Both placebo and BBIC showed a statistically significant decrease in mean lesion area of 17.1% and 20.6%, respectively, and partial or greater clinical responses of 30% and 28% respectively. No significant difference between placebo and study drug arms was observed. Histologic review, review of photographs of lesions, and comparison of serum neu protein and oral mucosal cell protease activity also did not show significant differences between study arms. Probable reasons for these negative results were considered, are discussed, and include a placebo with non-BBIC clinical activity and reduced pharmacokinetic availability of the second batch of BBIC. This experience should be a strong cautionary note to those considering "Green" chemoprevention.