Case report: coronectomy of an impacted and submerged second deciduous molar.

Coronectomy is a widely-accepted technique available for the treatment of impacted wisdom teeth. The fundamental principle is to prevent trauma to the inferior dental nerve (IDN). Many publications have demonstrated its positive outcomes but there is no literature available regarding coronectomy of deciduous teeth. This case report highlights the complex approach to managing a severely infraoccluded 85 in the mixed dentition of a 10-year-old female. The report demonstrates and discusses the combined orthodontic and oral surgical approach to prevent damage to the IDN and to allow space for orthodontic movement. This case demonstrates how nerve sparing techniques in the mixed dentition are achievable.Clinical relevance statement When managing severely infraoccluded and impacted deciduous second molars, clinicians must be aware that the option of a coronectomy should be considered and may be the difference between sparing the nerve or causing permanent injury.Objective The reader should understand that coronectomy is a suitable treatment option in managing impacted deciduous teeth.

Triploidy induction in Nile tilapia, Oreochromis niloticus L. using pressure, heat and cold shocks.

The results of a study aimed at the identification of treatment optima for triploidy induction in recently fertilised Oreochromis niloticus L. eggs by altering the intensity, duration and timing of application of pressure, heat and cold shocks are reported. Preliminary, but not directly comparable, trials suggested the following treatments to be close to the individual agent optima. Pressure: 8,000 psi 2-min duration applied 9 min after fertilisation (a.f.); heat: 41 °C, 3.5-min duration applied 5 min a.f., cold: 9°C, 30-min duration applied 7 min a.f. In a directly comparable trial in which the eggs of eight different females were separately exposed to the optimum shocks listed above, individual triploid yields were more variable following cold shocks and mean triploid yields were, therefore, higher following pressure and heat shock. These and other results obtained are presented and the light they shed on the timing of the second meiotic division in this species is discussed.