In the present study, the authors summarize and review data from 449 minimally invasive surgeries performed using a dental microscope between 2008 and 2012 on patients with moderate or severe periodontal disease.

Post-operative tooth preservation rate, including wisdom teeth, was high at approx. 97.05%. Average bleeding on probing (BOP) and pus discharge decreased from approx. 16.16 teeth before surgery to approx. 2.51 teeth after surgery.

Moreover, while the results varied according to site, it is possible that the surgeries enabled a relatively high improvement in periodontal pockets from ≥6 mm to ≤3 mm. A survey of pain medication use after surgery showed that approx. 16% of patients took multiple doses. The study findings suggest that using a dental microscope in surgery of moderate or severe periodontitis is very clinically effective because it enables a high degree of precision while minimizing both the surgical field and pain after surgery.

This case report emphasizes the clinical significance of the presence of a third canal in the mesiobuccal (MB) root of the maxillary first molar. We describe three cases in which non-surgical root canal treatment failed even though MB1 and MB2 were properly treated by an endodontist. Surgical intervention was attempted, in which the third MB canal was found and treated, resulting in good prognosis. Clinicians should be aware of the possibility of a third MB canal, and be proficient in surgical intervention as well as orthograde treatment in such cases.

Although various root canal configurations occur in upper second molar, C-shaped canal appears with the low frequency. This case report presents the retreatment of anomaly tooth that a fusion of the distobuccal and palatal canals produces C-shaped space. Teeth with C-shaped canals have an impact on treatment. Then, the dental microscope together with various instruments becomes powerful assistance for this case. ProRoot MTA was used for root canal obturation. Crack line in palatal canal was blocked using Super-Bond.

Six months after obturation, a follow-up X-ray was taken. The periapical healing was obvious. A combination of instruments and microscopes is useful and indispensable to treat and preserve the tooth having a root anomaly such as this case.

It is extremely worthwhile to be acquainted with the properties of sodium hypochlorite (NaClO), a substance that is useful for dental treatment. Notably, NaClO is essential for use in root canal cleaning. In this review, we explore the chemistry of NaClO, including the relationship between chemical equilibrium of free available chlorine and pH; bactericidal effects of NaClO; effects on biofilm of NaClO; effects of NaClO on resin bonding when used as a root canal irrigant; pH changes of NaClO, NaClO, and free radicals; NMR analysis of the pattern of collagen breakdown by NaClO during dissolution of organic material; cautions for root canal irrigation using NaClO and appropriate use of NaClO in root canal therapy; and NaClO stimulation of human tissue as assessed by histopathology.