According to pictures released on the Social Network Telegram on December 6, 2022, the Russian Ministry of Defense took delivery of a new improved version of the T-72B3M to replace the tanks that were destroyed or damaged during the fighting in Ukraine. Citing a Russian military source, this version of the T-72B3M was upgraded based on the combat experience gained in Ukraine.
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New upgraded T-72B3M tanks are carried on trains ready to be delivered to the Russian army. (Picture source Social Network Telegram)

The T-72B3M is an upgraded version of the T-72B3 which is the latest modernized version of the T-72. It was unveiled to the public during the Final of the International Russian army Tank Biathlon competition in October 2014. Citing a Russian source, the T-72B3M offers the same level of protection and firepower as the T-90 but at a much lower cost.
The new version of the T-72B3M has several new improvements in terms of firepower and protection. 

The new T-72B3 keeps the same armament as the previous version including a 2A46M5 125-mm smoothbore gun able to fire a wide range of 125mm ammunition including APDS (Armor-Piercing Discarding Sabot), HEF (High-Explosive Fragmentation), HEAT (High-Explosive Anti-Tank), and GM. The cannon can also fire the 9M119 Refleks (NATO designation AT-11 Sniper) anti-tank guided missile system with a range from 100 to 4,000 m.

In terms of protection, the new T-72B3M is fitted with dynamic protection around the hull. The turret seems to be fitted with a new ERA (Explosive Reactive Armor) all-around the turret. The lower part of the turret is now fitted with an RPG metal net offering more protection against Rocket-Propelled Grenades charges. The system is also mounted on the T-90M tank.

On the right of the turret is mounted a bank of eight smoke grenade dischargers which is now protected by a Kontakt-1 ERA armor.

Citing open source information, the Russian army will have lost a total of 193 T-72B3M tanks in Ukraine. Before the war, the Russian army had about 580 T-72B3M. So, the Russian army would have lost about 1/3 of these tanks. Despite international economic sanctions against Russia, tank production continues to fill the losses of combat vehicles in Ukraine.

Russian army T-72B3M main battle tank that was unveiled in 2016. (Picture source Vitaly Kuzmin)