diff --git a/code/modules/research/designs/medical_designs.dm b/code/modules/research/designs/medical_designs.dm
index 05f9ee6d07..457169c67f 100644
--- a/code/modules/research/designs/medical_designs.dm
+++ b/code/modules/research/designs/medical_designs.dm
@@ -708,7 +708,7 @@
 	id = "cybernetic_ears"
 	build_type = PROTOLATHE | MECHFAB
 	construction_time = 30
-	materials = list(/datum/material/iron = 250, /datum/material/glass = 400)
+	materials = list(MAT_METAL = 250, MAT_GLASS = 400)
 	build_path = /obj/item/organ/ears/cybernetic
 	category = list("Misc", "Medical Designs")
 	departmental_flags = DEPARTMENTAL_FLAG_MEDICAL
@@ -719,7 +719,7 @@
 	id = "cybernetic_ears_u"
 	build_type = PROTOLATHE | MECHFAB
 	construction_time = 40
-	materials = list(/datum/material/iron = 500, /datum/material/glass = 500, /datum/material/silver = 500)
+	materials = list(MAT_METAL = 500, MAT_GLASS = 500, MAT_SILVER = 500)
 	build_path = /obj/item/organ/ears/cybernetic/upgraded
 	category = list("Misc", "Medical Designs")
 	departmental_flags = DEPARTMENTAL_FLAG_MEDICAL
diff --git a/code/modules/surgery/organs/ears.dm b/code/modules/surgery/organs/ears.dm
index bc71a5cc95..0d3002915e 100644
--- a/code/modules/surgery/organs/ears.dm
+++ b/code/modules/surgery/organs/ears.dm
@@ -130,7 +130,6 @@
 	icon_state = "ears-c-u"
 	desc = "an advanced cybernetic ear, surpassing the performance of organic ears"
 	damage_multiplier = 0.5
-This conversation was marked as resolved by ExcessiveUseOfCobblestone
 
 /obj/item/organ/ears/cybernetic/emp_act(severity)
 	. = ..()
diff --git a/code/modules/surgery/organs/lungs.dm b/code/modules/surgery/organs/lungs.dm
index 94243b1eda..f3eaba1a1b 100644
--- a/code/modules/surgery/organs/lungs.dm
+++ b/code/modules/surgery/organs/lungs.dm
@@ -73,7 +73,7 @@
 
 //TODO: lung health affects lung function
 /obj/item/organ/lungs/onDamage(damage_mod) //damage might be too low atm.
-	cached_damage = damage
+	var/cached_damage = damage
 	if (maxHealth == INFINITY)
 		return
 	if(cached_damage+damage_mod < 0)
diff --git a/code/modules/surgery/organs/tongue.dm b/code/modules/surgery/organs/tongue.dm
index 91a29db813..e53723425d 100644
--- a/code/modules/surgery/organs/tongue.dm
+++ b/code/modules/surgery/organs/tongue.dm
@@ -30,13 +30,13 @@
 
 /obj/item/organ/tongue/proc/handle_speech(datum/source, list/speech_args)
 
-/obj/item/organ/tongue/proc/onDamage(damage_mod)
+/obj/item/organ/tongue/onDamage(damage_mod)
 	if (maxHealth == "alien")
 		return
 	if (maxHealth == "bone")
-		var/target = M.get_bodypart(BODY_ZONE_HEAD)
-		M.apply_damage(damage_mod, BURN, target)
-		to_chat(M, "<span class='userdanger'>The drink burns your skull! Oof, your bones!</span>")
+		var/target = owner.get_bodypart(BODY_ZONE_HEAD)
+		owner.apply_damage(damage_mod, BURN, target)
+		to_chat(owner, "<span class='userdanger'>The drink burns your skull! Oof, your bones!</span>")
 		return
 	if(damage+damage_mod < 0)
 		damage = 0
@@ -44,13 +44,13 @@
 
 	damage += damage_mod
 	if ((damage / maxHealth) > 1)
-		to_chat(M, "<span class='userdanger'>Your tongue is singed beyond recognition, and disintegrates!</span>")
+		to_chat(owner, "<span class='userdanger'>Your tongue is singed beyond recognition, and disintegrates!</span>")
 		SSblackbox.record_feedback("tally", "fermi_chem", 1, "Tongues lost to Fermi")
 		qdel(src)
 	else if ((damage / maxHealth) > 0.85)
-		to_chat(M, "<span class='warning'>Your tongue feels like it's about to fall out!.</span>")
+		to_chat(owner, "<span class='warning'>Your tongue feels like it's about to fall out!.</span>")
 	else if ((damage / maxHealth) > 0.5)
-		to_chat(M, "<span class='notice'>Your tongue is really starting to hurt.</span>")
+		to_chat(owner, "<span class='notice'>Your tongue is really starting to hurt.</span>")
 
 
 /obj/item/organ/tongue/Insert(mob/living/carbon/M, special = 0)