: 378  Obesity may be more likely to present among those with severe OI, (especially after the age of 20,) and can, in some, cause further declines in mobility. : 371, 373 Tilt table whole body vibration may also be done to increase the mobility of long-term immobilized (bedridden) patients with OI; in at least two cases it helped bedridden children to be able to sit upright. Teeth
More than 1 in 2 people with OI also have dentinogenesis imperfecta (DI)—a congenital abnormality in the formation of dentin, one of the four major components of the human tooth. Dental treatment may pose as a challenge as a result of the various deformities, skeletal and dental, due to OI. Children with OI should go for a dental check-up as soon as their teeth erupt; this may minimize tooth structure loss as a result of abnormal dentine, and they should be monitored regularly to preserve their teeth and oral health.Many people with OI are treated with bisphosphonates, and there are several possible related complications with dental procedures, for example, medication-related osteonecrosis of the jaw (MRONJ). However, no report of bisphosphonate-related MRONJ in either a child or adult with OI was found in a 2016 Cochrane review of the safety and efficacy of bisphosphonates for OI. In development
Monoclonal antibodies
Monoclonal antibodies have long been considered for OI, but as of 2021, such therapy has not been approved for OI, neither in the European Union nor in the United States. Thus, it is unclear whether they are safe or effective.
Type IV OI is mostly defined in contrast to type III and type I, being the clinical classification for patients somewhere in the middle ground between the two. : 1511  As such, type IV OI is often termed "variable" OI,: 111  with the severity of even those in the same family (so, with the same genetic mutation) differing.Prepubertal bone fracture rates are another way of clinically assessing type IV OI—those with it tend to have fracture rates of ≈1 per year, compared to ≈3 per year for severe OI (type III).As in type I, some further split type IV into types IV–A and IV–B, defined again by the absence (IV–A) or presence (IV–B) of dentinogenesis imperfecta. : 217

Genetically defined types (types V–XXI)
As of 2020, fifteen types of OI are defined genetically:

Type V – Having the same clinical features as type IV, it can be clinically distinguished by observing a "mesh-like" appearance to a bone biopsy under a microscope. Type V can be further distinguished from other types of OI by the "V triad": an opaque band (visible on X-ray) adjacent to the growth plates; hypertrophic calluses (abnormally large masses of bony repair tissue) which form at fracture sites during the healing process; and calcification of the interosseous membrane of the forearm, which may make it difficult to turn the wrist. : 429   Other features of this condition may include pulled elbow, and, as in other types of OI, long bone bowing and hearing loss. Cases of this type are caused by mutations in the IFITM5 gene on chromosome 11p15.5.