Short dental implants in reduced alveolar bone height.

Reduced alveolar bone height is very common in the posterior jaws. The current treatment modality to replace the missing teeth with an implant-retained fixed partial denture includes sinus bone grafting in the maxilla and onlay bone graft in the mandible. These procedures are invasive and require more time and cost. Short dental implants are used as an alternative treatment modality to bone grafting procedures. To enhance success rate, certain principles should apply. Short implants could provide comparable results to those of longer implants. This article reviews the current literature on the use of short implants, discusses the biomechanical considerations when utilizing short implants, and presents a case.

The development of emphysema in cigarette smoke-exposed mice is strain dependent.

Only 20% of smokers develop chronic obstructive pulmonary disease. An important determinant of susceptibility is genomic variation. We undertook this study to define strains of mice with different susceptibilities for the development of smoking-induced emphysema because they could help identify genetic factors of susceptibility. NZWLac/J, C57BL6/J, A/J, SJ/L, and AKR/J strains were exposed to cigarette smoke for 6 months. Elastance (Htis), the extent of emphysema (mean linear intercept [Lm]), and the inflammatory cell and cytokine response were measured. NZWLac/J had no change in Lm or Htis (resistant). C57BL6/J, A/J, and SJ/L increased Lm, but not Htis (mildly susceptible). AKR/J increased Lm and Htis (super-susceptible). Only AKR/J had significant inflammation comprising macrophages, neutrophils, and T cells. The AKR/J showed an upregulation of Th1 cytokines whereas in the C57BL/6/J and NZWlac/J, cytokines did not change or were downregulated. We conclude that Lm, elastance, and inflammation are features that are needed to phenotype emphysema in mice. The inflammatory cell and cytokine profile may be an important determinant of the phenotype in response to cigarette smoke exposure. The identification of resistant and susceptible strains for the development of emphysema could be useful for genomic studies of emphysema susceptibility in mice and eventually in humans.